YOUR VOTE IS IMPORTANT

It is important that your shares be voted at the Special Scheme Meeting and the Extraordinary General Meeting. Please MARK, SIGN, DATE, and MAIL your proxy PROMPTLY in the return envelope provided or appoint a proxy to vote your shares by telephone or by using the Internet, as described in the proxy statement.

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IN THE GRAND COURT OF THE CAYMAN ISLANDS
FINANCIAL SERVICES DIVISION

CAUSE NO FSD [      ] OF 2010

IN THE MATTER OF SEAGATE TECHNOLOGY

AND IN THE MATTER OF SECTION 86 OF THE COMPANIES LAW (2009 REVISION)

        NOTICE IS HEREBY GIVEN that, by an order dated [            ], 2010 (the "Order") made in the above matter, the Grand Court of the Cayman Islands (the "Cayman Court") has directed a meeting (the "Special Scheme Meeting") to be convened of the holders of common shares of Seagate Technology, for the purpose of considering and, if thought fit, approving, with or without modification, a scheme of arrangement (the "Scheme") proposed to be made between Seagate Technology, Seagate Technology plc, and the Common Shareholders (as defined in the Scheme) and that the Special Scheme Meeting will be held on            , 2010 at [10:00 a.m.], pacific time, at [*] at which place and time all such common shareholders are requested to attend.

        Copies of the Scheme of Arrangement and a copy of an explanatory statement explaining the effect of the Schemes are incorporated in the proxy statement of which this Notice forms part. A copy of the said proxy statement can also be obtained by the common shareholders from Seagate Technology's proxy solicitor in the United States being Morrow & Co., LLC 470 West Avenue, Stamford, CT 06902.

        The above-mentioned common shareholders as at the record date set by the Cayman Court, being            , 2010, may vote in person at the Special Scheme Meeting or they may appoint one or more proxies, whether a member of Seagate Technology or not, to attend and vote in their stead. A form of proxy for use at the Special Scheme Meeting is enclosed with the proxy statement of which this Notice forms part.

        If such common shares are held in joint names, then either the holder whose name appears first in the Register of Members of Seagate Technology or each holder should sign. If signing as Attorney, Executor, Administrator, Trustee or Guardian, please give your title as such. If the signer is a corporation, please sign in the full corporate name by a duly authorized officer.

        It is requested that forms appointing proxies be lodged, by post, fax or email, with Seagate Technology, c/o [*] in accordance with the instructions set out in the form of proxy, which proxy forms must be received by no later than [48 hours prior to the time of the Special Scheme Meeting], but if forms are not so lodged they may be handed to the chairman of the Special Scheme Meeting at the meeting.

        By the Order, the Cayman Court has appointed [*], a director of Seagate Technology, or failing [him][her] [*], also a director of Seagate Technology, or failing [him][her] any other person who is a director of Seagate Technology as at the date of the Special Scheme Meeting to act as the chairman of the Special Scheme Meeting and has directed the chairman of the Special Scheme Meeting to report the results thereof to the Cayman Court.

        The Scheme of Arrangement will be subject to a subsequent application seeking the sanction of the Cayman Court which shall be heard at 10.00 a.m. on                        2010 or as soon thereafter as it may be heard.

Dated the        day of                2010.

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SEAGATE TECHNOLOGY
PO Box 309, Ugland House, South Church Street, Grand Cayman, Cayman Islands

NOTICE OF EXTRAORDINARY GENERAL MEETING OF SHAREHOLDERS

To Be Held On                        , 2010

To the Common Shareholders of Seagate Technology:

        An Extraordinary General Meeting of the holders of common shares of Seagate Technology, a Cayman Islands exempted company limited by shares ("Seagate-Cayman" or the "Company"), will be held on [*], 2010, at [    •    ], or as soon thereafter as the Special Scheme Meeting is concluded or adjourned, at [Address] at which place and time all such shareholders are requested to attend:

1.

to approve the Capital Reduction Proposal and to pass a special resolution in the following terms:

THAT for the purpose of giving effect to the Scheme of Arrangement, at the Transaction Time (as defined in the Scheme of Arrangement):

(a)

the issued share capital of the Company shall be reduced by canceling and extinguishing the common shares issued by the Company, par value US$0.00001 per share (the "Scheme Shares");



(b)

subject to and forthwith upon such reduction of capital taking effect, the share capital of the Company will be increased to its former amount by the issue of the same number of common shares of US$0.00001 each in the capital of the Company as is equal to the number of Scheme Shares cancelled and extinguished; and



(c)

the Company shall apply the credit arising in its books of account as a result of such capital reduction in paying up in full at par the new common shares of US$0.00001 each in the capital of the Company issued, and credited as fully paid, to Seagate Technology plc, an Irish public limited company.



2.

to approve the Distributable Reserves Proposal;



3.

to approve a motion to adjourn the meeting to a later date to solicit additional proxies if there are insufficient proxies or shareholders present to conduct the vote on the Capital Reduction Proposal or the Distributable Reserves Proposal or if there are insufficent proxies to approve the Distributable Reserves Proposal and/or the Capital Reduction Proposal at the time of the meeting.

        The Board of Directors has set [    •    ] pm [*] on                        , 2010 as the record date (the "Record Date") for the determination of holders of common shares entitled to notice of and to vote at the Extraordinary General Meeting or any adjournment thereof. Only holders of record of common shares of Seagate-Cayman as of [*] on the Record Date are entitled to notice of and to vote at the Extraordinary General Meeting.

        Your vote is important. All shareholders are cordially invited to attend the Extraordinary General Meeting. We urge you, whether or not you plan to attend the Extraordinary General Meeting, to submit your proxy by telephone or via the internet, or by completing, signing, dating and mailing the enclosed proxy or voting instruction card. If a shareholder who has submitted a proxy attends the Extraordinary General Meeting in person, such member may revoke the proxy by voting in person on all matters submitted at the Extraordinary General Meeting.

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        Capitalized terms in this notice have the same meaning as in the proxy statement to which this notice is attached, (the "Proxy Statement") and in the draft Scheme of Arrangement which is attached as Annex A thereto.

By Order of the Board of Directors
Kenneth M. Massaroni
Secretary
[*], 2010

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PROXY STATEMENT

For the Special Court Ordered Meeting and the Extraordinary General Meeting of Shareholders
to be held on [*]

        This proxy statement is furnished to the common shareholders of Seagate Technology, an exempted company incorporated with limited liability under the laws of the Cayman Islands ("Seagate-Cayman"), in connection with the solicitation of proxies on behalf of the board of directors of Seagate-Cayman to be voted at a special court ordered meeting of shareholders ("Special Scheme Meeting"), followed immediately by an Extraordinary General Meeting of shareholders ("Extraordinary General Meeting" or "EGM" and together with the Special Scheme Meeting, the "Meetings") to be held on [*], and any adjournments or postponements thereof, at the times and places and for the purposes set forth in the accompanying Notice of Special Scheme Meeting and Extraordinary General Meeting. This proxy statement and the accompanying proxy card are first being mailed to Seagate-Cayman common shareholders on or about [*]. Please mark, date, sign and return the enclosed proxy card to ensure that all of your shares are represented at the Meetings.

        Shares represented by valid proxies will be voted in accordance with instructions contained therein or, in the absence of such instructions, at the proxy's discretion. You may revoke your proxy at any time before it is exercised at either of the Meetings by voting in person at that Meeting. You may also submit another properly signed, later-dated proxy (including an Internet or telephone proxy) or notify our Secretary in writing before the Meetings that you are revoking your proxy, which proxy or notice must be received no later than [*] on [*]. If you hold your shares beneficially and are not a registered shareholder, please follow the procedures required by your broker, custodian or nominee to revoke a proxy. You should contact your broker, custodian or nominee directly for more information on these procedures.

        The Grand Court of the Cayman Islands (the "Cayman Court") (in the case of the Special Scheme Meeting) and the board of directors (in the case of the EGM) has fixed [*] on [*] (the "Record Date") as the record date for determination of common shareholders entitled to notice of, and to vote at, both the Special Scheme Meeting and the Extraordinary General Meeting and any adjournments or postponements thereof. As of the Record Date, there were [*] common shares of Seagate-Cayman issued and outstanding and we had [*] shareholders of record.

        All shareholders of Seagate-Cayman are invited to attend the Meetings. If you wish to attend the Meetings in person, a form of personal identification and proof of address, must be presented in order to be admitted to the Meetings.

        If your shares are held in the name of a bank, broker or other holder of record and you plan to attend the Meetings, you must present proof of your ownership of common shares, such as a bank or brokerage account statement, together with a form of personal identification and proof of address, to be admitted to the meeting.

        The enclosed proxy is solicited by and on behalf of our board of directors.

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CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

        Some of the statements included in this proxy statement and the documents incorporated by reference may include forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 or Section 21E of the Securities Exchange Act of 1934, each as amended, including, in particular, statements about our expectations regarding the change of our place of incorporation from the Cayman Islands to Ireland. These statements identify prospective information and include words such as "expects," "plans," "anticipates," "believes," "estimates," "predicts," "projects" and similar expressions. These forward-looking statements are based on information available to us as of the date of this proxy statement.

        Current expectations, forecasts and assumptions involve a number of risks, uncertainties and other factors that could cause actual results to differ materially from those anticipated by these forward-looking statements. Such risks, uncertainties and other factors that could cause actual results and experience to differ from those projected include, but are not limited to, the following:

•

the ineffectiveness of our business strategy due to changes in current or future market conditions;



•

the effects of our competing in a highly competitive industry, including industry consolidation, pricing competition and development of competing products;



•

decreased demand for our products;



•

our dependence on our ability to successfully qualify, manufacture and sell our disk drive products in increasing volumes on a cost-effective basis and with acceptable quality, particularly our new disk drive products with lower cost structures;



•

weakness in the global economy and decreased spending on information technology;



•

the risk that legislative and regulatory action by the U.S. government could materially and adversely affect our effective tax rate and cash tax position;



•

risks associated with the proposed scheme of arrangement and the creation of a new parent holding company in Ireland;



•

uncertainties relating to governmental and regulatory policies; and



•

tax liabilities such as dividend withholding tax and stamp duty.

        The foregoing review of important factors should not be construed as exhaustive and should be read in conjunction with the other cautionary statements that are set forth in this proxy statement, in particular in the section entitled "Risk Factors" and the documents that we file with the Securities and Exchange Commission (the "SEC") from time to time. You may obtain copies of these documents as described under the heading "Where You Can Find More Information."

        Except as required under U.S. federal securities laws and the rules and regulations of the SEC, we do not have any intention or obligation to update publicly any forward-looking statements after the distribution of this proxy statement, whether as a result of new information, future events, changes in assumptions or otherwise.

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STRUCTURE OF THE TRANSACTION

        We are seeking your approval of a scheme of arrangement under Cayman Islands law, substantially in the form attached as Annex A to this proxy statement (the "Scheme of Arrangement") which, upon effectiveness, will result in a newly formed Irish public limited company serving as the publicly traded parent of the Seagate group of companies (the "Seagate group"). In this proxy statement, we refer to the transactions to be effected pursuant to the Scheme of Arrangement and the related transactions as the "Transaction." The Transaction will effectively change the place of incorporation of the publicly traded parent company of the Seagate group from the Cayman Islands to Ireland and will result in you holding ordinary shares of an Irish company instead of common shares of a Cayman Islands company.

        The Transaction will involve several steps. We have formed a new Irish public limited company, Seagate Technology plc ("Seagate-Ireland"), as a direct subsidiary of Seagate Technology, the Cayman Islands company whose shares you currently own ("Seagate-Cayman"). A new Cayman Islands subsidiary of Seagate-Ireland named Seagate Cayman Holdings ("merger sub") has also been formed. Each of Seagate-Ireland and merger sub has only nominal assets and capitalization and has not engaged in any business or other activities other than in connection with its formation and the Transactions.

        Various steps of the Transactions will effectively occur simultaneously at the "Transaction Time", which we anticipate will be after the close of trading on NASDAQ on the day the Scheme of Arrangement becomes effective, which we expect to be [*], and before the opening of trading on NASDAQ on the next business day. If we receive the necessary shareholder approvals, we anticipate that the Scheme of Arrangement will become effective as soon as practicable following approval of the Cayman Court at the hearing on [*], upon our filing of the court order sanctioning the Scheme of Arrangement and the cancellation of the capital of Seagate-Cayman with the Cayman Islands registrar of companies.

        At the Transaction Time, the following steps of the Transaction will effectively occur simultaneously:

•

all issued and outstanding Seagate-Cayman common shares shall be cancelled and shall cease to exist;



•

Seagate-Ireland will issue ordinary shares on a one-for-one basis to the holders of Seagate-Cayman common shares for each Seagate-Cayman common share that has been cancelled;



•

in consideration for the issuance by Seagate-Ireland of its ordinary shares to the Seagate-Cayman common shareholders as set forth in the second bullet above, Seagate-Cayman will allot and issue a number of fully-paid Seagate-Cayman common shares to Seagate-Ireland that is equal to the number of Seagate-Ireland ordinary shares issued to the holders of Seagate-Cayman common shares that were cancelled as set forth in the first bullet above; and



•

pursuant to a separate, but related, scheme of arrangement (the "Merger Scheme"), Seagate-Cayman will merge with merger sub, Seagate-Cayman will survive the merger, merger sub will be dissolved and will cease to exist and Seagate-Cayman will become a direct, wholly-owned subsidiary of Seagate-Ireland, the resulting publicly traded parent of the Seagate group. Holders of common shares in Seagate-Cayman will not be required to vote in connection with the Merger Scheme.

        If, and only if, the Scheme of Arrangement and the Merger Scheme are effected, an election will be made to treat Seagate-Cayman as a disregarded entity for U.S. federal income tax purposes, effective shortly after the Transaction Time.

        All previously outstanding ordinary shares of Seagate-Ireland, which prior to the Transaction Time will be held by Seagate-Cayman and its nominees, will be acquired by Seagate-Ireland for no

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consideration and cancelled in accordance with a resolution passed by Seagate-Cayman and the other current shareholders of Seagate-Ireland.

        As a result of the Transaction, the common shareholders of Seagate-Cayman will become shareholders of Seagate-Ireland and such shareholders' rights will be governed by Irish law and Seagate-Ireland's memorandum and articles of association, which are attached to the proxy statement as Annex B.

        The following diagram depicts our organizational structure before and after the Transaction.

        As of [*], the Record Date, there were [*] common shares of Seagate-Cayman issued and outstanding and we had [*] shareholders of record.

        In this proxy statement, we sometimes refer to Seagate-Cayman, Seagate-Ireland and the Seagate group as "we," "us," "our" or "Seagate."

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QUESTIONS AND ANSWERS ABOUT THE TRANSACTIONS AND THE MEETINGS

Q.    What am I being asked to vote on at the Meetings?

A.

Common shareholders of Seagate-Cayman are being asked to vote on the following four matters:

At the Special Scheme Meeting:

•

to approve the Scheme of Arrangement attached as Annex A to this proxy statement. If the Scheme of Arrangement becomes effective, the common shares of Seagate-Cayman will be cancelled and Seagate-Ireland will issue one ordinary share to the holders of Seagate-Cayman common shares for each common share of Seagate-Cayman that has been cancelled. As a result, Seagate-Ireland will become the parent holding company of Seagate-Cayman. We refer to this proposal as the "Scheme of Arrangement Proposal"; and



•

to approve a motion to adjourn the Special Scheme Meeting to a later date to solicit additional proxies if there are insufficient proxies to approve the proposals at the time of the Special Scheme Meeting.

At the Extraordinary General Meeting, if the Scheme of Arrangement Proposal is approved by the common shareholders at the Special Scheme Meeting:

•

to approve the reduction of Seagate-Cayman's share capital, which is necessary in order to effect the Transaction. We refer to this proposal as the "Capital Reduction Proposal";



•

to approve the creation of "distributable reserves" of Seagate-Ireland through a reduction of Seagate-Ireland's share premium account. We refer to this proposal as the "Distributable Reserves Proposal"; and



•

to approve a motion to adjourn the Extraordinary General Meeting to a later date to solicit additional proxies if there are insufficient shareholders present at the Extraordinary General Meeting to conduct the vote on or if their are insufficient proxies to approve the Capital Reduction Proposal or the Distributable Reserves Proposal.

Q:    Who can vote?

A:

Holders of Seagate-Cayman common shares as recorded in our register of members as of the Record Date are entitled to vote. Our register of members will be available for inspection at least 10 days prior to the meeting at [*]. As of the Record Date, there were [*] common shares of Seagate-Cayman issued and outstanding and entitled to vote and we had [*] shareholders of record. Each holder of Seagate-Cayman common shares is entitled to one vote per share.

Q.    When is the Record Date?

A.

The record date for both the Special Scheme Meeting and the Extraordinary General Meeting is [**] on [**], 2010.

Q.    Why do you want to change Seagate's place of incorporation from the Cayman Islands to Ireland?

A.

We have been incorporated in the Cayman Islands since August 10, 2000. While our tenure in the Cayman Islands has served us and our shareholders well, the board of directors has had cause to revisit the decision regarding the location of our place of incorporation.

There continues to be negative publicity regarding, and criticism of, companies that conduct business in the U.S. but are domiciled in countries that have low rates of, or no direct taxation and as a consequence do not have a substantial network of double taxation (or similar) treaties with the U.S. or with many of countries where we have operations. Furthermore, legislative and

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regulatory bodies in various jurisdictions, including the U.S., have actively considered proposals and/or introduced legislation that, if enacted, could increase our tax burden if we remained incorporated in the Cayman Islands. For example, recent legislative proposals could broaden the circumstances under which we would be considered a U.S. resident or could override certain tax treaties and limit the treaty benefits on certain payments by our U.S. subsidiaries to our non-U.S. affiliates. Consequently, following a thorough review, we have determined that moving our place of incorporation out of the Cayman Islands will reduce those risks and is best for Seagate-Cayman, our shareholders, our employees and other stakeholders.

After considering various factors and reviewing a number of different countries, our board of directors determined that it was advisable to change the jurisdiction of incorporation of the parent company of the Seagate group to Ireland. Our board of directors' determination that Ireland is the preferred choice for the domicile of the parent of the Seagate group was based on many factors, including the following:

•

Ireland has strong international relationships as a member of the EU and a long history of international investment and long-established commercial relationships, trade agreements and tax treaties with the other EU member states, the U.S. and other countries around the world where we do business. Ireland is also a founding member of the Organisation for Economic Co-operation and Development ("OECD"). As a result, we believe Ireland offers a stable long-term legal and regulatory environment with the financial and legal infrastructure to meet our needs;



•

Ireland is an English-speaking common law jurisdiction, which we believe makes its legal system less prescriptive and more flexible than those of civil law jurisdictions and also more familiar to Seagate and its shareholders;



•

Ireland has a stable and well-developed legal system which we believe encourages high standards of corporate governance and provides shareholders with substantial rights. We believe that the perception of an Irish company among regulatory authorities, investors, creditors and customers is highly favorable;



•

Ireland as a member of the EU will enable favorable EU tax directives and other protections to apply to us;



•

Ireland permits the payment of dividends in U.S. Dollars;



•

Ireland's taxation system and large double taxation network will enable us to maintain a competitive worldwide effective corporate tax rate; and



•

Ireland is the only English-speaking member of the group of EU states that have adopted the Euro as their exclusive currency, known as the eurozone.

As a result of these factors, our board of directors determined that it was advisable to change our place of incorporation to Ireland. Please see "Proposal Number One: The Scheme of Arrangement—Background and Reasons for the Transaction" for more information. We cannot assure you that the anticipated benefits of the Transaction will be realized. In addition to the potential benefits described above, the Transaction will expose you and us to some risks. Please see the discussion under "Risk Factors." Our board of directors has considered both the potential advantages of the Transaction and these risks and has approved the Scheme of Arrangement and recommended that the shareholders vote for the approval of the Scheme of Arrangement.

Q:    Are there any risks associated with the consummation of the Transaction?

A:

While our board of directors has considered the risks to our shareholders and us associated with the Transaction and has recommended that shareholders vote for approval of the Scheme of

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Arrangement Proposal and each of the other proposals set forth in this proxy statement, there are risks and we cannot assure you that the anticipated benefits of the Transaction will be realized. For example:

•

your rights as a shareholder will change due to differences between the Cayman Islands and Irish law and between the governing documents of Seagate-Cayman and Seagate-Ireland;



•

our effective tax rate may increase whether we effect the Transaction or not;



•

legislative and regulatory action could materially and adversely affect us regardless of whether we complete the Transaction;



•

the Transaction may result in additional costs even if it is not completed;



•

potential changes may be required to the terms of our indentures in connection with obtaining any appropriate consents, waivers and/or supplemental indentures required or necessary in connection with the Transaction;



•

we may choose to abandon the Transaction;



•

if the distributable reserves proposal is not approved by the shareholders and the Irish High Court, Seagate-Ireland may not be able to pay dividends or repurchase shares following the Transaction;



•

increased shareholder voting requirements in Ireland will reduce our flexibility in some aspects of capital management and our ability to amend the articles of association;



•

Seagate-Ireland may be subject to takeover regulation under Irish law which would not apply in the Cayman Islands;



•

the transfer of Seagate-Ireland shares after the Transaction may be subject to Irish stamp duty for certain shareholders;



•

dividends paid following the Transaction may be subject to Irish dividend withholding tax or Irish income tax for certain shareholders; and



•

the market for Seagate-Ireland shares may differ from the market for Seagate-Cayman shares.

You should consider these risks carefully. For additional information, please see the discussion under "Risk Factors."

Q.    Will the Transaction affect Seagate's current or future operations?

A.

We believe that the Transaction will have no material impact on how we conduct our day-to-day operations.

Q:    How will shares of Seagate-Ireland differ from shares of Seagate-Cayman?

A:

Seagate-Ireland ordinary shares will be similar to Seagate-Cayman common shares. However, there are differences between what your rights as an ordinary shareholder will be under Irish law and what they currently are as a common shareholder under Cayman Islands law. In addition, there are differences between the organizational documents of Seagate-Ireland and Seagate-Cayman. These differences include the following:

•

Seagate-Ireland's articles of association will contain a more limited form of indemnity in relation to directors and the Secretary than is currently contained in the articles of association of Seagate-Cayman.

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•

A special resolution of Seagate-Ireland, which is required for certain corporate actions such as amending the memorandum and articles of association of Seagate-Ireland, will require the approval of not less than 75% of votes cast while a special resolution of Seagate-Cayman, which is required for many of the same actions, currently requires not less than two thirds of votes cast.



•

Under Irish law, the directors of Seagate-Ireland may issue new ordinary or preferred shares up to a maximum amount equal to the authorized but un-issued share capital, without shareholder approval, only when authorized to do so by the articles of association of Seagate-Ireland or by an ordinary resolution of the Seagate-Ireland shareholders. The authorization of the directors to issue shares must renewed by the shareholders at least every five years.



•

Subject to specified exceptions, Irish law grants statutory pre-emptive rights to existing shareholders to subscribe for new issuances of shares for cash, but allows shareholders to authorize the waiver of the statutory pre-emptive rights with respect to any particular allotment of shares. The waiver of the statutory pre-emptive rights must be renewed by the shareholders at least every five years.



•

Under Irish law, dividends must be paid and share repurchases must generally be funded out of "distributable reserves," which Seagate-Ireland will not have immediately following the Transaction Time. Although we are taking steps to create such distributable reserves, if the shareholders of Seagate-Cayman approve the Scheme of Arrangement, but do not approve the distributable reserves proposal, and the Transaction is consummated, Seagate-Ireland may not have sufficient distributable reserves to pay dividends or to repurchase or redeem shares following the Transaction, including under the current share repurchase plans of Seagate-Cayman until such time as Seagate-Ireland has created distributable reserves through the generation of future profits from its operations. Please see "Risk Factors" and "Proposal Number Three: Creation of Distributable Reserves."

We discuss these and other differences in detail under "Description of Seagate Technology plc Share Capital" and "Comparison of Rights of Shareholders and Powers of the Board of Directors." The form of Seagate-Ireland's memorandum and articles of association is attached to this proxy statement as Annex B.

Q.    How will the Transaction affect Seagate's presence in the U.S. and around the world?

A.

Except for our increased presence in Ireland, at present, there are no changes planned for our operations or workforce in the U.S. or elsewhere as a result of the Transaction.

Q.    What will be Seagate's corporate presence in Ireland?

A.

Seagate-Ireland has been incorporated in Ireland and is subject to Irish law. Our current intention is that we will hold a majority of our regularly scheduled meetings of the board of directors in Ireland. However, at this time, we do not expect to hold our annual general meeting of shareholders in Ireland and we do not plan for our shares to be listed on the Irish Stock Exchange. If the Transaction becomes effective, we intend to hire additional employees in Ireland to assist with board meetings and other head office functions.

Q.    Will the Transaction dilute my economic interest?

A.

No, your relative economic ownership in Seagate will not change as a result of the Transaction.

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Q.    How will the Transaction affect Seagate's financial reporting and the information Seagate provides to its shareholders?

A.

Upon completion of the transaction, we will remain subject to the U.S. Securities and Exchange Commission reporting requirements, the mandates of the Sarbanes-Oxley Act and the applicable corporate governance rules of the NASDAQ, and we will continue to report our consolidated financial results in U.S. dollars and in accordance with U.S. generally accepted accounting principles. We will continue to file reports on Forms 10-K, 10-Q and 8-K with the U.S. Securities and Exchange Commission and comply with the proxy rules, as we currently do. We will also comply with any additional reporting requirements of Irish law.

Q.    What impact will the Transaction have on Seagate's current debt arrangements?

A.

We expect no material impact on our senior notes or our credit agreement. In connection with the Transaction, Seagate-Ireland expects to seek consents or waivers and/or enter into supplemental indentures to the indentures governing certain of our outstanding notes, including pursuant to which supplemental indentures Seagate-Ireland will guarantee the obligations of the issuers of certain of the notes and assume the obligations of a parent entity under the indentures. We are seeking waivers and will amend our credit agreement in order to avoid any technical defaults that would otherwise result in connection with the Transaction and to provide that Seagate-Ireland will guarantee the obligations of the borrower under our credit agreement. One of the conditions to consummation of the Transaction is that we obtain consents or waivers and/or enter into a supplemental indenture, with respect to the indenture governing our outstanding 10.00% senior secured second-priority notes due 2014 issued by Seagate Technology International, on terms acceptable to us. Please see "Proposal Number One: The Scheme of Arrangement—Conditions to Consummation of the Transaction."

Q.    Will the Transaction impact Seagate's ability to access the capital and bank markets in the future?

A.

We do not expect that the Transaction will have any significant effect on our ability to access the capital and bank markets. We expect to be able to access the capital and bank markets as efficiently and on similar terms as we can today, subject to any changes in market conditions applicable in general to all companies.

Q.    Will the Transaction have any impact on Seagate's ability to pay dividends or buy back shares?

A.

Under Irish law, dividends must be paid and share repurchases must generally be funded out of "distributable reserves," which Seagate-Ireland will not have immediately following the Transaction Time. Please see "Description of Seagate Technology plc Share Capital—Dividends" and "—Share Repurchases, Redemptions and Conversions." The shareholders of Seagate-Cayman are being asked at the Extraordinary General Meeting, subject to the approval of the Scheme of Arrangement, to approve the creation of distributable reserves of Seagate-Ireland (through the reduction of the share premium account of Seagate-Ireland), in order to provide us with the flexibility to pay dividends and repurchase or redeem shares following the Transaction should the board of directors decide to do so. Approval of the Distributable Reserves Proposal is not a condition to the Transaction, but is required under Irish law to allow us to pay dividends or repurchase or redeem shares following the Transaction. Accordingly, if the shareholders of Seagate-Cayman approve the Scheme of Arrangement, but do not approve the distributable reserves proposal, and the Transaction is consummated, Seagate-Ireland may not have sufficient distributable reserves to pay dividends or to repurchase or redeem shares following the Transaction, including under the current share repurchase plans of Seagate-Cayman until such time as Seagate-Ireland has created distributable reserves through the generation of future profits from

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its operations. The creation of distributable reserves also requires the approval of the Irish High Court. Although we are not aware of any reason why the Irish High Court would not approve the creation of distributable reserves, the issuance of the required order is a matter for the discretion of the Irish High Court and there is no guarantee that such approval will be forthcoming. Further, even if the Distributable Reserves Proposal is approved, we can provide no assurance that we will pay dividends or redeem or repurchase shares. Please see "Risk Factors" and "Proposal Number Three: Creation of Distributable Reserves."

Q.    What effect would the failure to complete the Transaction have on Seagate?

A.

We have incurred and will incur certain costs whether or not the Transaction is completed. We will consider all possible alternatives in the event that the Transaction is not completed. However, we may experience adverse tax consequences if the Transaction is not completed as currently contemplated. For more information, please see "Risk Factors."

Q.    Am I entitled to appraisal or dissenters' rights in the Transaction?

A.

No. Under Cayman Islands law, the common shareholders of Seagate-Cayman do not have dissenters' rights or a right to an appraisal of the value of their shares or receive payment for them in connection with the Transaction.

Q.    What are the material tax consequences of the Transaction?

A.

Please read the following questions and answers regarding some of the potential tax consequences of the Transaction. Please refer to "Material Tax Considerations Relating to the Transaction" for a description of the material U.S. federal income tax, Irish tax, and Cayman Islands tax consequences of the Transaction to Seagate-Cayman common shareholders. Determining the actual tax consequences of the Transaction to you may be complex and will depend on your specific situation. We urge you to consult your tax advisor for a full understanding of the tax consequences of the Transaction to you.

Q.    Is the Transaction taxable to me?

A.

Under U.S. federal income tax law, holders of common shares of Seagate-Cayman generally should not recognize gain or loss in the Transaction. Under Irish tax law, no tax is due for Seagate-Cayman's common shareholders in the Transaction unless such shareholders are resident or ordinarily resident in Ireland for Irish tax purposes or hold their shares in Seagate-Cayman in connection with a trade carried on by such holder in Ireland through a branch or agency. Please see "Material Tax Considerations Relating to the Transaction."

Q.    Is the Transaction a taxable transaction for Seagate-Cayman or Seagate-Ireland?

A.

No. The Transaction should not be a taxable transaction for Seagate-Cayman or Seagate-Ireland.

Q.    Will the Transaction impact Seagate's underlying effective tax rate in 2010—or expectations for later years?

A.

The Transaction is not anticipated to have any material impact on our underlying effective tax rate. However, see "Risk Factors—Our effective tax rate may increase whether we effect the Transaction or not."

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Q:    Will there be an Irish withholding tax on dividends on Seagate-Ireland shares?

A:

Distributions made to Seagate-Ireland shareholders who are residents of the U.S., EU member states (other than Ireland), or other countries with which Ireland has signed a tax treaty (whether the treaty has been ratified or not) (as set forth in Annex C) generally should not be subject to Irish withholding tax so long as the shareholder has provided its broker, for onward transmission to Seagate-Ireland's qualifying intermediary (or other designated agent) (in the case of shares held beneficiary), or Seagate-Ireland or its transfer agent (in the case of shares held directly), with all the necessary documentation prior to payment of the dividend. Distributions made by Seagate-Ireland to shareholders will generally be subject to Irish dividend withholding tax at the standard rate of income tax (currently 20%) unless the shareholder is a shareholder described above or qualifies for another exemption and in all instances has provided its broker, for onward transmission to Seagate-Ireland's qualifying intermediary (or other designated agent) (in the case of shares held beneficially), or Seagate-Ireland or its transfer agent (in the case of shares held directly), with all the necessary documentation prior to payment of the dividend. Where Irish dividend withholding tax applies, Seagate-Ireland is responsible for withholding tax at source and forwarding the relevant payment to the Irish Revenue Commissioners. Please see "Material Tax Considerations Relating to the Transaction—Irish Tax Considerations—Withholding Tax on Dividends".

Q:    Will there be Irish income tax on dividends paid on Seagate-Ireland shares?

A:

Shareholders who are resident in or ordinarily resident in Ireland for Irish tax purposes or who hold their shares in Seagate-Ireland in connection with a trade carried on by such holder in Ireland through a branch or agency will generally be subject to Irish income tax on dividends paid by Seagate-Ireland. All other shareholders will generally not be required to pay Irish income tax on such dividends unless they are subject to Irish dividend withholding tax in which case the Irish dividend withholding tax will satisfy such shareholder's liability with respect to Irish income tax. Please see "Material Tax Considerations Relating to the Transaction—Irish Tax Considerations—Withholding Tax on Dividends."

Q:    Will there be an Irish stamp duty on the transfer of Seagate-Ireland shares?

A:

For the majority of transfers of Seagate-Ireland ordinary shares, we do not expect there to be any Irish stamp duty. Transfers of book-entry interests in Depository Trust Company ("DTC") representing Seagate-Ireland shares should not be subject to Irish stamp duty. Accordingly, transfers by shareholders who hold their Seagate-Ireland shares beneficially through brokers, which in turn hold those shares through DTC, should not be subject to Irish stamp duty on transfers to holders who also hold through DTC. Transfers by shareholders who hold their shares other than beneficially through DTC, will be subject to Irish stamp duty, which is a legal obligation of the buyer. Irish stamp duty is currently 1% of the price paid or the market value of the shares acquired, if higher. Accordingly, we recommend that all directly registered shareholders open broker accounts so they can transfer their Seagate-Cayman shares into a broker account to be held through DTC as soon as possible, and in any event, prior to the Transaction Time. This will cause their Seagate-Ireland shares to be held through DTC from the Transaction Time. We also recommend that any person who wishes to acquire Seagate-Ireland shares after completion of the Transaction acquire such Seagate-Ireland shares beneficially through a broker account to be held through DTC. In relation to any transfer of Seagate-Ireland shares that is subject to Irish stamp duty, Seagate-Ireland's articles of association allow Seagate-Ireland, in its absolute discretion, to create an instrument of transfer and pay (or procure the payment of) any stamp duty payable by a buyer. In the event of any such payment, Seagate-Ireland is (on behalf of itself or its affiliates) entitled to (i) seek reimbursement from the buyer or seller (at its discretion), (ii) set-off the

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amount of the stamp duty against future dividends payable to the buyer or seller (at its discretion), and (iii) claim a lien against the Seagate-Ireland shares on which it has paid stamp duty. Parties to a share transfer may assume that any stamp duty arising in respect of a transaction in Seagate-Ireland shares has been paid unless one or both of such parties is otherwise notified by us.

Please see "Material Tax Considerations Relating to the Transaction—Irish Tax Considerations—Stamp Duty" for a more detailed description of the Irish stamp duty.

Q.    Does it matter, for tax or other reasons, whether I hold my shares "beneficially" or "of record?"

A.

Yes, in general, Seagate-Cayman shareholders hold their shares in one of two ways. Some shareholders are directly registered in their own names on Seagate-Cayman shareholder records, as maintained by Seagate-Cayman transfer agent (currently Computershare Trust Company, Inc.). In this proxy statement, we generally refer to these shareholders as holding their shares "directly" or "of record." Most Seagate-Cayman shareholders hold their shares through banks, brokers, trustees, custodians or other nominees who in turn hold their shares through the DTC. We generally refer to these shares as being held "beneficially," and to these banks, brokers, trustees, custodians or other nominees as "brokers."

In addition, there are different procedures for voting and attending the Meetings, depending on how you hold your shares. Only shareholders of record are entitled to vote at the Meetings. If you hold your shares beneficially, you may still be entitled to direct the direct holder of your shares how to vote these shares on your behalf. However, in that case your vote will not be counted toward the majority-in-number requirement for the purposes of the Special Scheme Meeting (although your vote will be counted for the purposes of the majority-in-value calculation, and for the majorities at the EGM. Please see "The Special Scheme Meeting and the Extraordinary General Meeting—Record Date; Voting Rights; Vote Required for Approval" and "—How You Can Vote."

In addition, following the Transaction, shareholders may be treated differently under certain aspects of Irish law depending on whether they hold shares beneficially through brokers who in turn hold those shares through the DTC. Please see "Material Tax Considerations Relating to the Transaction—Irish Tax Considerations—Withholding Tax on Dividends" and "—Stamp Duty."

Q.    Will the Transaction have any material impact on another company's ability to acquire Seagate?

A.

The Transaction should not materially affect the ability of another company to acquire Seagate. However, after the Transaction, Seagate-Ireland will be subject to the Irish Takeover Panel Act of 1997 and the Takeover Rules promulgated thereunder which require review of certain acquisitions by the Irish Takeover Panel. The Cayman Islands does not have similar laws, rules or regulations that currently apply to us as a Cayman Islands company. Please see "Comparison of Rights of Shareholders and Powers of the Board of Directors—Shareholder Approval of Business Combinations," "—Appraisal Rights," and "—Other Anti-Takeover Measures."

Q.    When do you expect the Transaction to be completed?

A.

We are working towards completing the Transaction as quickly as possible and, assuming the Scheme of Arrangement is approved by the requisite vote of Seagate-Cayman shareholders and by the Cayman Court and the other conditions to the consummation of the Transaction are satisfied (and we do not abandon the Transaction), we expect to do so as soon as practicable following the receipt of the necessary approvals. We currently expect to complete the Transaction in the fourth quarter of fiscal year 2010. Please see Annex E to this proxy statement for an expected timetable. However, the Transaction may be abandoned or delayed by our board of directors at any time prior to the Transaction Time without obtaining the approval of Seagate-Cayman shareholders,

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even though the Scheme of Arrangement may have been approved by Seagate-Cayman shareholders and sanctioned by the Cayman Court and all other conditions to the Transaction may have been satisfied. Please see "Proposal Number One: The Scheme of Arrangement—Amendment, Termination or Delay."

Q.    What will I receive for my Seagate-Cayman common shares?

A.

You will receive one ordinary share of Seagate-Ireland for each common share of Seagate-Cayman you held immediately prior to the completion of the Transaction.

Q.    If the Scheme of Arrangement is approved, do I have to take any action to cancel my Seagate-Cayman common shares and receive Seagate-Ireland ordinary shares?

A.

No. Assuming the Transaction becomes effective, your Seagate-Cayman common shares will be cancelled and Seagate-Ireland ordinary shares will be issued without any action on your part, regardless of whether you currently hold Seagate-Cayman common shares in certificated form or uncertificated book-entry form. All of Seagate-Ireland's shares will be issued in uncertificated book-entry form. Consequently, if you currently hold Seagate-Cayman common shares in certificated form, following the Transaction your Seagate-Cayman share certificates will cease to have effect as documents or evidence of title and you may disregard such certificates. The transfer agent will make an electronic book-entry in your name and will mail you a statement evidencing your ownership of Seagate-Ireland shares. Please see "Proposal Number One: The Scheme of Arrangement—No Action Required to Cancel Seagate-Cayman Common Shares and Receive Seagate-Ireland Ordinary Shares."

Q.    Can I trade Seagate-Cayman common shares between the date of this proxy statement and the Transaction Time?

A.

Yes. Seagate-Cayman common shares will continue to trade during this period.

Q.    How will the Transaction affect the stock exchange listing of Seagate shares?

A.

There should be no disruption in the trading of your shares. We intend to file an application with the NASDAQ and expect that, immediately following the Transaction Time, the Seagate-Ireland ordinary shares will be listed on the NASDAQ under the symbol "STX," the same symbol under which your Seagate-Cayman common shares are currently listed. We do not plan for Seagate-Ireland's ordinary shares to be listed on the Irish Stock Exchange.

Q:    What quorum is required for action at the Special Scheme Meeting and the Extraordinary General Meeting?

A:

At the Special Scheme Meeting, at least two common shareholders must be present, in person or by proxy, in order for the meeting to proceed. At the Extraordinary General Meeting, the presence, in person or by proxy, of one or more shareholders holding not less than a majority of the issued and outstanding shares of the company constitutes a quorum. Abstentions and broker non-votes will be counted as present for purposes of determining whether there is a quorum in respect of the proposals.

Please see "The Extraordinary General Meeting—Record Date; Voting Rights; Vote Required for Approval."

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Q:    What vote of Seagate-Cayman shareholders is required to approve the proposals?

A:

The Scheme of Arrangement Proposal must be approved by a majority in number of the holders of the Seagate-Cayman common shares present and voting on the proposal, whether in person or by proxy, representing 75% or more in value of the Seagate-Cayman common shares present and voting on the proposal, whether in person or by proxy. For the purpose of calculating the "majority in number" requirement for the approval of the proposal, each registered shareholder, present and voting in person or by proxy, will be counted as a single shareholder, regardless of the number of shares voted by that shareholder. If a registered shareholder elects to vote a portion of such holder's Seagate-Cayman common shares in favor of the proposal, and a portion against the proposal, then, subject to any reasonable objection that may be raised, that registered shareholder will be counted as one shareholder voting in favor of the proposal and as one shareholder voting against the proposal, thereby effectively canceling out that registered shareholder's vote for the purposes of the "majority in number" calculation.

The Capital Reduction Proposal must be approved by a majority of at least two thirds of the Seagate-Cayman common shares present and voting, whether in person or by proxy.

The Distributable Reserves Proposal must be approved by more than 50% of all common shares present and voting, in person or by proxy, on the Distributable Reserves Proposal. Approval of the Distributable Reserves Proposal by our common shareholders is not a condition to the effectiveness of the Scheme of Arrangement, but the Board may determine not to proceed with the Transaction for any reason, including because the Distributable Reserves Proposal is not approved.

The adjournment proposals, if presented, must be approved by more than 50% of all common shares present and voting, in person or by proxy.

Because the quorum for the Special Scheme Meeting is the presence of at least two common shareholders and the quorum for the Extraordinary General Meeting is the presence in person or by proxy of shareholders holding a majority of the issued and outstanding Seagate-Cayman common shares, but for each proposal, the voting requirement is determined by the number of shareholders who are present and voting at the applicable meeting, each of the proposals could be approved with the affirmative vote of less than 50% of the issued and outstanding Seagate-Cayman common shares.

Q:    What is the effect of Broker Non-Votes and Abstentions?

A:

Brokers who hold shares on behalf of customers have the authority to vote on "routine" proposals when they have not received instructions from beneficial owners, but are precluded from exercising their discretionary voting power with respect to proposals for "non-routine" matters. A broker non-vote occurs when a broker holding shares for a beneficial owner does not vote on a particular proposal because the broker does not have discretionary voting power for that particular item and has not received instructions from the beneficial owner. We believe that all of the proposals are "non-routine" proposals, so your broker will not be able to vote your shares without appropriate instructions for you. It is important you follow your broker's instructions and vote.

Common shares owned by shareholders electing to abstain from voting with respect to any proposal and broker non-votes will be counted towards the determination of a quorum at each of the Meetings but will not be considered present and voting with respect to any of the proposals. Therefore, abstentions and broker non-votes will have no effect on the outcome of such proposals.

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Q.    What vote does the board of directors recommend?

A.

The Seagate-Cayman board of directors recommends that you vote "FOR" the Scheme of Arrangement Proposal, "FOR" the Capital Reduction Proposal, "FOR" the Distributable Reserves Proposal and "FOR" each of the proposals to adjourn the Special Scheme Meeting or the Extraordinary General Meeting to a later date or dates, if necessary, to solicit additional proxies.

Q.    How do I attend the Special Scheme Meeting and the Extraordinary General Meeting?

A.

All shareholders of Seagate-Cayman are invited to attend the Meetings at [*], located at [*] commencing at [*] on [*].

If your shares are held in the name of a bank, broker or other holder of record and you plan to attend the Meetings, you must present proof of your beneficial ownership of shares, such as a bank or brokerage account statement or letter from your bank, broker or other nominee showing that you owned Seagate shares as of the record date, together with a form of personal identification and proof of address to be admitted to the Meetings. If you would rather have an admission ticket, you can obtain one in advance by mailing a written request, along with proof of your beneficial ownership of shares, to:

Company Secretary
c/o Office of the General Counsel
Seagate Technology
920 Disc Drive
Scotts Valley, CA 95066

Even if you establish proof of your beneficial ownership and/or have a valid admission ticket, you will not be entitled to vote at or otherwise participate in the Meetings unless you are a shareholder of record. Only shareholders, their proxy holders and Seagate's guests may attend the Meetings.

Q.    How do I vote?

A.

You may vote in person at the Meetings or by proxy. We recommend that you vote by proxy even if you expect to attend the Meetings. You will be able to revoke your proxy by voting in person at the Meetings. Giving us your proxy means you authorize the Chairman of the meeting (or such other person as you may nominate) to vote your shares at the Meetings or at any adjournments or postponement thereof in the manner you direct. You may vote for or against any or all of the proposals or abstain from voting. If you sign and return the enclosed proxy card but do not specify how to vote, we will vote your shares in favor of all proposals, pursuant to the recommendation of the board of directors. You can cast your votes by proxy by:

•

using the Internet or telephone to appoint proxies to cast your vote by following the instructions on the enclosed proxy card; or

•

completing, signing, dating and returning the enclosed proxy card.

Executors, administrators, trustees, guardians, attorneys and other representatives should indicate the capacity in which they are signing and corporations should sign by an authorized officer whose title should be indicated.

The procedures for Internet appointment of a proxy are designed to authenticate the appointment of a proxy to cast your vote by use of a personal identification number. The procedures allow shareholders to appoint a proxy to vote their shares and to confirm that their instructions have been properly recorded. If you are a shareholder of record and you would like to appoint your proxy to vote by Internet, please refer to the specific instructions contained on the enclosed proxy card. If you appoint your proxy to vote by Internet, you do not need to return the enclosed proxy

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card. In order to be timely processed, an Internet appointment must be received by [*] on [*]. For more details about Internet proxies, please see "The Special Scheme Meeting and the Extraordinary General Meeting—How You Can Vote."

Q.    If my shares are held in "street name" by my broker, will my broker vote my shares for me?

A.

You should have received a copy of this proxy statement and instructions on how to instruct your broker to vote your shares. If you have not received a proxy statement and instructions, we recommend that you contact your broker, as shareholders who hold their shares through a broker must vote their shares in the manner prescribed by their broker. Your broker can give you directions on how to instruct the broker to vote your shares.

Your broker may not be able to vote your shares unless the broker receives appropriate instructions from you. Brokers who hold shares on behalf of customers have the authority to vote on "routine" proposals when they have not received instructions from beneficial owners, but are precluded from exercising their voting discretion with respect to proposals for "non-routine" matters. Proxies submitted by brokers without instructions from customers for these non-routine matters are referred to as "broker non-votes." We believe that all of the proposals are "non-routine" proposals, so your broker will not be able to vote your shares without appropriate instructions for you. It is important you follow your broker's instructions and vote.

Q.    May I revoke my proxy?

A.

Yes. You may revoke your proxy at any time before it is exercised at the Special Scheme Meeting or the Extraordinary General Meeting in any of the following ways:

•

by notifying Seagate-Cayman's Secretary in writing: Company Secretary, c/o Office of the General Counsel, Seagate Technology, 920 Disc Drive, Scotts Valley, CA 95066, which notice must be received no later than [*] on [*];

•

by submitting another properly signed proxy card with a later date or another telephone or Internet proxy at a later date, which proxy must be received no later than [*] on [*]; or

•

by voting in person at the applicable Meeting.

You do not revoke a proxy merely by attending the Special Scheme Meeting or the Extraordinary General Meeting. To revoke a proxy, you must take one of the actions described above.

If your shares are held in a stock brokerage account or by a bank or other nominee on your behalf, follow the instructions provided to you by your broker in order to revoke your proxy.

Q.    How will the votes be counted and the results certified?

A.

Broadridge has been appointed as the independent Inspector of Election and will count the votes, determine the existence of a quorum, validity of proxies and ballots, and certify the results of the voting.

Q.    Is my vote confidential?

A.

Proxy cards, proxies delivered by Internet or telephone, ballots and voting tabulations that identify individual shareholders are mailed or returned directly to the independent Inspector of Election, Broadridge and to the Chairman of the Meetings, and handled in a manner that protects your voting privacy. Your vote will not be disclosed either within Seagate or to third parties, except:

•

as necessary to meet applicable legal requirements;

•

to allow for the tabulation and certification of votes; and

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•

to facilitate a successful proxy solicitation.

Occasionally, shareholders provide written comments on their proxy card, which may be forwarded to management and the board of directors.

Q.    Why am I receiving paper copies of these proxy materials when I received only a "Notice of Internet Availability of Proxy Materials" for the Company's annual general meeting?

A.

Due to the expected timing of the Transaction, we chose to distribute paper copies of these proxy materials instead of distributing these materials solely via the Internet. We expect to return to the Internet distribution approach in connection with our next annual general meeting.

Q.    Who is making and paying for this proxy solicitation?

A.

The proxy is being solicited on behalf of the board of directors of Seagate-Cayman. We have hired Morrow & Co., LLC to assist in the distribution of proxy materials and the solicitation of proxies for an initial fee estimated at $8,500, plus an additional fee per shareholder for shareholder solicitations. We will bear the cost of soliciting proxies, which we do not expect to exceed $15,000. We will also reimburse brokers for their reasonable out-of-pocket expenses for forwarding proxy materials to beneficial owners of Seagate-Cayman shares or other persons for whom they hold Seagate-Cayman shares. To the extent necessary in order to ensure sufficient representation at its meeting, Seagate or its proxy solicitor may solicit the return of proxies by personal interview, mail, telephone, facsimile, Internet or other means of electronic transmission. The extent to which this will be necessary depends upon how promptly proxies are returned. We urge you to send in your proxy without delay.

Q.    How will my proxy get voted?

A.

If you properly complete, sign and date the enclosed proxy card and send it to us or properly appoint your proxy by telephone or over the Internet, your proxy holder (one of the individuals named on the enclosed proxy card) will vote your shares as you have directed.

If you do not wish to vote all of your Seagate-Cayman shares in the same manner on any particular proposal(s), you may split your vote by clearly hand-marking the reverse side of the proxy card to indicate how you want to vote your common shares. You may not split your vote if you are lodging your proxy by the Internet.

If you wish to appoint a proxy other than the Chairman of the Meetings, you may nominate another proxy by clearly hand-marking the reverse side of the proxy card to indicate who you wish to be your proxy at the Meetings. You may not appoint a proxy other than the Chairman if you are lodging your proxy by the Internet.

If you do not specify on the enclosed proxy card that is submitted (or when providing your proxy over the Internet or by telephone) how you want to vote your common shares, and if you appoint the Chairman of the Meetings as your proxy, the Chairman will vote your common shares "FOR" each of the proposals set forth in this proxy statement.

Q.    Whom should I call if I have questions about the Special Scheme Meeting, the Extraordinary General Meeting or the Transaction?

A.

You should contact our proxy solicitor:

Morrow & Co., LLC
470 West Avenue
Stamford, CT 06902
(800)-607-0088
Brokers and banks please call: (203) 658-9400

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SUMMARY

        This summary highlights selected information from this proxy statement. It does not contain all of the information that is important to you. To understand the Transaction more fully, and for a more complete legal description of the Transaction, you should read carefully the entire proxy statement, including the Annexes. The Scheme of Arrangement, substantially in the form attached as Annex A to this proxy statement, is the legal document that governs the Transaction. The memorandum and articles of association of Seagate-Ireland, substantially in the form attached as Annex B to this proxy statement, will govern Seagate-Ireland after the completion of the Transaction. We encourage you to read those documents carefully.

Parties to the Transaction

        Seagate-Cayman.    We are the world's leading provider of hard disk drives based on revenue. We design, manufacture, market and sell hard disk drives. We produce a broad range of disk drive products addressing enterprise applications, where our products are used in enterprise servers, mainframes and workstations; desktop applications, where our products are used in desktop computers; mobile computing applications, where our products are used in notebook computers; and consumer electronics applications, where our products are used in a wide variety of devices such as digital video recorders (DVRs) and other consumer electronic devices that require storage. We also sell our branded storage solutions under both the Seagate and Maxtor brands. In addition to manufacturing and selling disk drives, we provide data storage services for small- to medium-sized businesses, including online backup, data protection and recovery solutions.

        We are a global corporation with offices, suppliers, customers and competitors on every continent. We employ more than 51,000 people worldwide, of which more than 43,000 are involved in our Asia operations. We generate over 70% of our revenues outside North America through sales offices located in Australia, China, France, Germany, India, Japan, Taiwan and the United Kingdom. Our principal manufacturing facilities are located in China, Malaysia, Northern Ireland, Singapore, Thailand and the U.S. We have been incorporated in the Cayman Islands since August 10, 2000. Our common shares are traded on the NASDAQ Global Select Market under the symbol "STX".

        Seagate-Ireland.    Seagate-Ireland is a newly formed Irish company and is currently wholly-owned by Seagate-Cayman, except for six shares that are held in trust for Seagate-Cayman by six nominees to satisfy Irish legal requirements with respect to the shareholding structure of an Irish plc. Seagate-Ireland has only nominal assets and capitalization and has not engaged in any business or other activities other than in connection with its formation and the Transaction. Immediately following the Transaction, Seagate-Ireland will become the parent holding company of the Seagate group.

        Merger sub.    Merger sub is a company newly organized under the laws of the Cayman Islands for the purpose of merging with Seagate-Cayman in the Transaction, with Seagate-Cayman as the surviving company. Merger sub is a direct, wholly-owned subsidiary of Seagate-Ireland. Merger sub has only nominal assets and capitalization and has not engaged in any business or other activities other than in connection with its formation and the Transaction. As a result of the Transaction, merger sub will be dissolved and will cease to exist.

        The principal executive offices of Seagate-Cayman and merger sub are located at 920 Disc Drive, Scotts Valley, California 95066. The telephone number of each party at that address is (345) 949-8066. The registered offices of Seagate-Ireland are located at Arthur Cox Building, Earlsfort Terrace, Dublin 2, Ireland, and the telephone number at that address is 353-1-6180517.

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The Transaction

        The Transaction will effectively change the place of incorporation of the publicly traded parent of the Seagate group from the Cayman Islands to Ireland.

        The Transaction involves several steps. On December 14, 2009, the board of directors of Seagate-Cayman held a board meeting in Dublin, Ireland to, among other things, discuss a potential transaction to change the place of incorporation of Seagate-Cayman. On January 22, 2010, Seagate-Cayman, the Cayman Islands company whose common shares you currently own, formed Seagate-Ireland as a direct subsidiary. On January 27, 2010, the board of directors of Seagate-Cayman held a board meeting in Dublin, Ireland to, among other things, approve the Transaction and the Scheme of Arrangement. On [*], we petitioned the Cayman Court to order, among other things, the calling of the Special Scheme Meeting to approve the Scheme of Arrangement. We will hold the Special Scheme Meeting to approve the Scheme of Arrangement and the EGM on [*], 2010. If we obtain the necessary shareholder approvals, the Cayman Court will hold the Sanction Hearing, which is expected to be held on [*], 2010, to sanction the Scheme of Arrangement and confirming the associated capital reduction. Assuming we receive the necessary approvals from Seagate-Cayman's shareholders and the Cayman Court and the conditions to consummate the Transaction are satisfied (and we do not abandon the Transaction), we will file the court order sanctioning the Scheme of Arrangement with the Cayman Islands Registrar of Companies, at which time the Scheme of Arrangement will be effective on its terms. Various steps of the Transaction will effectively occur simultaneously at the Transaction Time, which we anticipate will be after the close of trading on NASDAQ on the day the Scheme of Arrangement becomes effective, which we expect to be [*], and before the opening of trading on NASDAQ on the next business day.

        At the Transaction Time, the following steps of the Transaction will effectively occur simultaneously:

•

all issued and outstanding Seagate-Cayman common shares shall be cancelled and shall cease to exist;



•

Seagate-Ireland will issue ordinary shares on a one-for-one basis to the holders of Seagate-Cayman common shares for each Seagate-Cayman common share that has been cancelled;



•

in consideration for the issuance by Seagate-Ireland of its ordinary shares to the Seagate-Cayman common shareholders as set forth in the second bullet above, Seagate-Cayman will allot and issue a number of fully-paid Seagate-Cayman common shares to Seagate-Ireland that is equal to the number of Seagate-Ireland ordinary shares issued to the holders of Seagate-Cayman common shares that were cancelled as set forth in the first bullet above; and



•

pursuant to the Merger Scheme, Seagate-Cayman will merge with merger sub, Seagate-Cayman will survive the merger, merger sub will be dissolved and will cease to exist and Seagate-Cayman will become a direct, wholly-owned subsidiary of Seagate-Ireland, the resulting publicly traded parent of the Seagate group of companies. Holders of common shares in Seagate-Cayman will not be required to vote in connection with the Merger Scheme.

        If, and only if, the Scheme of Arrangement and the Merger Scheme are effected, an election will be made to treat Seagate-Cayman as a disregarded entity for U.S. federal income tax purposes, effective shortly after the Transaction Time.

        All previously outstanding ordinary shares of Seagate-Ireland, which prior to the Transaction Time will be held by Seagate-Cayman and its nominees, will be acquired by Seagate-Ireland for no consideration and cancelled in accordance with a resolution passed by Seagate-Cayman and the other current shareholders of Seagate-Ireland.

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        As a result of the Transaction, the common shareholders of Seagate-Cayman will become shareholders of Seagate-Ireland, and Seagate-Cayman will become a wholly-owned subsidiary of Seagate-Ireland.

        In connection with the completion of the Transaction, Seagate-Ireland will assume, on a one-for-one basis, Seagate-Cayman's existing obligations in connection with awards granted under Seagate-Cayman's equity incentive plans and other similar equity awards. Seagate-Ireland will also become a guarantor under certain of the indentures governing our outstanding notes and our credit agreement and will assume the obligations of a parent entity under the indentures. Please see "Proposal Number One: The Scheme of Arrangement—Supplemental Indentures." In addition, any securities issued by Seagate-Cayman or its subsidiaries that are convertible, exchangeable or exercisable into common shares of Seagate-Cayman will become convertible, exchangeable or exercisable, as the case may be, into ordinary shares of Seagate-Ireland.

        After the Transaction, you will continue to own an interest in a parent company that will continue to conduct, through its subsidiaries, the same businesses as conducted by Seagate-Cayman before the Transaction. The number of shares you will own in Seagate-Ireland immediately after the Transaction will be the same as the number of shares you owned in Seagate-Cayman immediately prior to the Transaction, and your relative economic interest in the Seagate group will remain unchanged.

        The completion of the Transaction will change the governing corporate law that applies to shareholders of our parent company from Cayman Islands law to Irish law. The legal system governing corporations organized under Irish law differs from the legal system governing corporations organized under Cayman Islands law. As a result, we are unable to adopt governing documents for Seagate-Ireland that are identical to the governing documents for Seagate-Cayman. We have attempted to preserve in the memorandum and articles of association of Seagate-Ireland the same allocation of material rights and powers between the shareholders and our board of directors that exists under Seagate-Cayman's memorandum and articles of association. Nevertheless, Seagate-Ireland's proposed memorandum and articles of association differ from Seagate-Cayman's memorandum and articles of association. We summarize the material differences between the governing documents for Seagate-Cayman and Seagate-Ireland, and the changes in your rights as a shareholder resulting from the Transaction, under "Comparison of Rights of Shareholders."

        Upon completion of the Transaction, we will remain subject to the U.S. Securities and Exchange Commission ("SEC") reporting requirements, the mandates of the Sarbanes-Oxley Act and the applicable corporate governance rules of NASDAQ, and we will continue to report our consolidated financial results in U.S. dollars and under U.S. generally accepted accounting principles ("U.S. GAAP").

        The Transaction will be effected pursuant to the Scheme of Arrangement, which is the primary legal document that will govern the Transaction. A copy of the Scheme of Arrangement is attached to and is a part of this proxy statement as Annex A.

Reasons for the Transaction

        We have been incorporated in the Cayman Islands since August 10, 2000. While our tenure in the Cayman Islands has served us and our shareholders well, the board of directors has had cause to revisit the decision regarding the location of our place of incorporation.

        There continues to be negative publicity regarding, and criticism of, companies that conduct business in the U.S. but are domiciled in countries that have low rates of, or no direct taxation and as a consequence do not have a substantial network of double taxation (or similar) treaties with the U.S. or with many of countries where we have operations. Furthermore, legislative and regulatory bodies in various jurisdictions, including the U.S., have actively considered proposals and/or introduced legislation that, if enacted, could increase our tax burden if we remained incorporated in the Cayman Islands. For

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example, recent legislative proposals could broaden the circumstances under which we would be considered a U.S. resident or could override certain tax treaties and limit the treaty benefits on certain payments by our U.S. subsidiaries to our non-U.S. affiliates. Consequently, following a thorough review, we have determined that moving our place of incorporation out of the Cayman Islands will reduce those risks and is best for Seagate-Cayman, our shareholders, our employees and other stakeholders.

        After considering various factors and reviewing a number of different countries, our board of directors determined that it was advisable to change the jurisdiction of incorporation of the parent company of the Seagate group to Ireland. Our board of directors' determination that Ireland is the preferred choice for the domicile of the parent of the Seagate group was based on many factors, including the following:

•

Ireland has strong international relationships as a member of the EU and a long history of international investment and long-established commercial relationships, trade agreements and tax treaties with the other EU member states, the U.S. and other countries around the world where we do business. Ireland is also a founding member of the OECD. As a result, we believe Ireland offers a stable long-term legal and regulatory environment with the financial and legal infrastructure to meet our needs;



•

Ireland is an English-speaking common law jurisdiction, which we believe makes its legal system less prescriptive and more flexible than those of civil law jurisdictions and also more familiar to Seagate and its shareholders;



•

Ireland has a stable and well-developed legal system which we believe encourages high standards of corporate governance and provides shareholders with substantial rights. We believe that the perception of an Irish company among regulatory authorities, investors, creditors and customers is highly favorable;



•

Ireland as a member of the EU will enable favorable EU tax directives and other protections to apply to us;



•

Ireland permits the payment of dividends in U.S. Dollars;



•

Ireland's taxation system and large double taxation network will enable us to maintain a competitive worldwide effective corporate tax rate; and



•

Ireland is the only English-speaking member of the eurozone.

        As a result of these factors, our board of directors determined that it was advisable to change our place of incorporation to Ireland. Please see "Proposal Number One: The Scheme of Arrangement—Background and Reasons for the Transaction" for more information. We cannot assure you that the anticipated benefits of the Transaction will be realized. In addition to the potential benefits described above, the Transaction will expose you and us to some risks. Please see the discussion under "Risk Factors." Our board of directors has considered both the potential advantages of the Transaction and these risks and has approved the Scheme of Arrangement and recommended that the shareholders vote for the approval of the Scheme of Arrangement.

Tax Considerations

        Under U.S. federal income tax law, holders of common shares of Seagate-Cayman generally should not recognize any gain or loss in the Transaction. Under Irish tax law, no tax is due for Seagate-Cayman common shareholders in the Transaction unless such shareholders are resident or ordinarily resident in Ireland for Irish tax purposes or hold their shares of Seagate-Cayman in connection with a trade carried on by such holder in Ireland through a branch or agency. Please refer to "Material Tax Considerations Relating to the Transaction" for a description of the material U.S. federal income tax, Irish tax, and Cayman Islands tax consequences of the Transaction to Seagate-Cayman common

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shareholders. Determining the actual tax consequences of the Transaction to you may be complex and will depend on your specific situation. We urge you to consult your tax advisor for a full understanding of the tax consequences of the Transaction to you.

Rights of Shareholders

        Many of the principal attributes of Seagate-Cayman's common shares and Seagate-Ireland's ordinary shares will be similar. However, there are differences between what your rights will be under Irish law and what they currently are under Cayman Islands law. In addition, there are differences between Seagate-Cayman's memorandum and articles of association and Seagate-Ireland's memorandum and articles of association as they will be in effect after the Transaction. We discuss these differences in detail under "Description of Seagate Technology plc Share Capital" and "Comparison of Rights of Shareholders and Powers of the Board of Directors." Seagate-Ireland's memorandum and articles of association in the form substantially as they will be in effect after the Transaction are attached as Annex B to this proxy statement.

Stock Exchange Listing

        We intend to file an application with the NASDAQ and expect that, immediately following the Transaction Time, the Seagate-Ireland ordinary shares will be listed on the NASDAQ under the symbol "STX," the same symbol under which your Seagate-Cayman common shares are currently listed.

Court Sanction of the Scheme of Arrangement

        We cannot complete the Transaction without the sanction of the Scheme of Arrangement by the Cayman Court. Subject to the common shareholders of Seagate-Cayman approving the Scheme of Arrangement, the Cayman Court will hold the Sanction Hearing, which is expected to be held on [*], 2010, to sanction of the Scheme of Arrangement. At the Sanction Hearing, the Cayman Court may impose such conditions as it deems appropriate in relation to the Scheme of Arrangement, but may not impose any material changes without the joint consent of Seagate-Cayman and Seagate-Ireland. Seagate-Cayman may, subject to U.S. securities law constraints, consent to any modification of the Scheme of Arrangement on behalf of the shareholders which the Cayman Court may think fit to approve or impose. In determining whether to exercise its discretion and sanction the Scheme of Arrangement, the Cayman Court will determine, among other things, whether the Scheme of Arrangement is fair to Seagate-Cayman's shareholders.

        If you are a common shareholder who wishes to appear in person or by counsel at the Sanction Hearing and present evidence or arguments in support of or opposition to the Scheme of Arrangement, you may do so. In addition, the Cayman Court has wide discretion to hear from interested parties. Seagate-Cayman will not object to the participation in the Sanction Hearing by any common shareholder who holds shares through a depository, custodian or broker.

Creation of Distributable Reserves

        Under Irish law, Seagate-Ireland requires "distributable reserves" in its unconsolidated balance sheet prepared in accordance with the Irish Companies Acts 1963-2009 (the "Irish Companies Acts") to enable it to make distributions (including the payment of cash dividends) to its shareholders, or generally to redeem or repurchase shares. Please see "Description of Seagate Technology plc Share Capital—Dividends" and "—Share Repurchases, Redemptions and Conversions." Immediately following implementation of the Transaction, the unconsolidated balance sheet of Seagate-Ireland will not contain any distributable reserves. The current shareholders of Seagate-Ireland (which are Seagate-Cayman and its nominees) have passed a resolution that would allow for the creation of distributable reserves following the Transaction by reducing the share premium account of Seagate-Ireland. If the

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Scheme of Arrangement is approved, common shareholders of Seagate-Cayman will also be asked at the Extraordinary General Meeting to approve the creation of distributable reserves of Seagate-Ireland that was previously approved by Seagate-Cayman and the other current shareholders of Seagate-Ireland. If the shareholders of Seagate-Cayman approve the reduction of share premium account of Seagate-Ireland to allow the creation of distributable reserves and the Transaction is completed, we will seek to obtain the approval of the Irish High Court, which is required for the creation of distributable reserves to be effective, as soon as practicable following implementation of the Transaction. Although we are not aware of any reason why the Irish High Court would not approve the creation of the distributable reserves, there is no guarantee that such approval will be forthcoming. Nonetheless, we anticipate the approval of the Irish High Court to be obtained within six weeks of the consummation of the Transaction. Please see "Risk Factors" and "Proposal Number Three: Creation of Distributable Reserves."

Supplemental Indentures

        In connection with the Transaction, we expect Seagate-Ireland to seek consents or waivers and enter into a supplemental indenture to the indenture governing the 10.00% senior secured second-priority notes due 2014 issued by Seagate Technology International. We expect the supplemental indenture will provide that Seagate-Ireland will guarantee the obligations of the issuer and assume the obligations of the parent entity under such indenture. Additionally, we expect Seagate-Ireland to enter into supplemental indentures to the indentures governing the following notes issued by current subsidiaries of Seagate Cayman: (i) the 2.375% Convertible Senior Notes due 2012 issued by Seagate Technology (US) Holdings, Inc. ("STUS"), 5.75% convertible subordinated debentures due 2012 issued by STUS and the 6.8% convertible senior secured notes due 2010 issued by STUS. Similarly, we expect the supplemental indentures will provide that Seagate-Ireland will guarantee the obligations of the issuer and assume the obligations of the parent entity under such indentures.

        One of the conditions to consummation of the Transaction is that we obtain consents or waivers and enter into a supplemental indenture, with respect to the indenture governing the 10.00% senior secured second-priority notes due 2014 issued by Seagate Technology International, on terms acceptable to us. Please see "Proposal Number One: The Scheme of Arrangement—Conditions to Consummation of the Transaction." Although we expect that no material change would be made to the terms of such indenture in connection with entering into such supplemental indenture, we cannot guarantee that there would not be any such change.

Credit Facility

        We are seeking waivers and an amendment to our credit agreement in order to avoid technical defaults that would otherwise result from the Transaction. We expect that the amendment will also provide that Seagate-Ireland will guarantee the obligations of the borrower under our credit agreement.

Market Price and Dividend Information

        On [*], 2010, the last trading day before the public announcement of the Transaction, the closing price of the Seagate-Cayman common shares on the NASDAQ was $[*] per share. On [*], 2010, the most recent practicable date before the date of this proxy statement, the closing price of the Seagate-Cayman common shares on the NASDAQ was $[*] per share.

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        Seagate-Cayman has not paid a dividend since February 20, 2009. Since the closing of our initial public offering in December 2002, Seagate-Cayman has paid dividends totaling approximately $952 million in the aggregate. The following are dividends paid in the last two fiscal years:

        However, on April 13, 2009, Seagate-Cayman announced that it had adopted a policy of no longer paying a quarterly dividend to its common shareholders to enhance liquidity. We do not expect to resume paying dividends for the foreseeable future.

No Appraisal Rights

        Under Cayman Islands law, the common shareholders of Seagate-Cayman do not have any dissenters' rights or right to an appraisal of the value of their shares or receive payment for them in connection with the Transaction.

Accounting Treatment of the Transaction

        Under U.S. GAAP, the Transaction represents a transaction between entities under common control. Assets and liabilities are transferred at carrying value between entities under common control. Accordingly, the assets and liabilities of Seagate-Ireland will be reflected at the same carrying amounts as in the accounts of Seagate-Cayman at the effective time of the Scheme of Arrangement.

Special Scheme Meeting

        Time, Place, Date and Purpose.    The Special Scheme Meeting will be held on [*] at [*] at [*]. At the Special Scheme Meeting, Seagate-Cayman's board of directors will ask the common shareholders of Seagate-Cayman to vote to approve the Scheme of Arrangement. If the Scheme of Arrangement is approved and becomes effective, it will effect the Transaction, pursuant to which your common shares of Seagate-Cayman will be cancelled and you will receive, on a one-for-one basis, new ordinary shares of Seagate-Ireland for each common share of Seagate-Cayman that has been cancelled.

        The common shareholders may also be asked to approve a motion to adjourn the Special Scheme Meeting to a later date to solicit additional proxies if there are insufficient proxies or shareholders to approve the proposals at the time of the Special Scheme Meeting or if there are insufficient proxies or shareholders present at the Extraordinary General Meeting to conduct the vote on the Capital Reduction Proposal or the Distributable Reserves Proposal.

        Record Date.    Only holders of record of Seagate-Cayman common shares as of the Record Date are entitled to notice of and to vote at the meeting or any adjournments or postponements of the meeting.

        Quorum.    At least two common shareholders must be present, in person or by proxy, in order for the Special Scheme Meeting to proceed.

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Extraordinary General Meeting

        Time, Place, Date and Purpose.    The Extraordinary General Meeting will be held on [*] at [*] at [*] (or as soon thereafter as the Special Scheme Meeting concludes). At the Extraordinary General Meeting, if the Scheme of Arrangement is approved at the Special Scheme Meeting, Seagate-Cayman's board of directors will ask the common shareholders of Seagate-Cayman to vote:

        1.     to approve the cancellation of Seagate-Cayman's share capital, which is necessary in order to effect the Transaction; and

        2.     to approve the creation of distributable reserves of Seagate-Ireland (through the reduction of the share premium account of Seagate-Ireland) that was previously approved by Seagate-Cayman and the other current shareholders of Seagate-Ireland (as described in this proxy statement).

        The common shareholders may also be asked to approve a motion to adjourn the Extraordinary General Meeting to a later date to solicit additional proxies if there are insufficient proxies or shareholders to approve the proposals at the time of the Special Scheme Meeting or if there are insufficient proxies or shareholders present at the Extraordinary General Meeting to conduct the vote on the Capital Reduction Proposal or the Distributable Reserves Proposal.

        Record Date.    Only holders of record of Seagate-Cayman common shares as of the Record Date are entitled to notice of and to vote at the Extraordinary General Meeting or any adjournments or postponements of the Extraordinary General Meeting.

        Quorum.    Shareholders present in person or by proxy holding not less than a majority of the issued and outstanding shares of Seagate-Cayman constitutes a quorum for the conduct of business at the Extraordinary General Meeting. Abstentions and broker non-votes will be counted as present for purposes of determining whether there is a quorum in respect of the proposals. A broker "non-vote" occurs when a nominee (such as a broker) holding shares for a beneficial owner abstains from voting on a particular proposal because the nominee does not have discretionary voting power for that proposal and has not received instructions from the beneficial owner on how to vote those shares.

Recommendation of the Board of Directors

        The Seagate-Cayman board of directors recommends that Seagate-Cayman shareholders vote "FOR" the Scheme of Arrangement Proposal, "FOR" the Capital Reduction Proposal, "FOR" the Distributable Reserves Proposal and "FOR" each of the proposals to adjourn the meeting to a later date or dates, if necessary to solicit additional proxies. Approval of the Capital Reduction Proposal is necessary for the Transaction to proceed. Approval of the Distributable Reserves Proposal is not a condition to the Transaction, but is required under Irish law in order for us to pay dividends or repurchase shares following the Transaction.

Required Vote

        The Scheme of Arrangement Proposal must be approved by a majority in number of the holders of the Seagate-Cayman common shares present and voting on the proposal, whether in person or by proxy, representing 75% or more in value of the Seagate-Cayman common shares present and voting on the proposal, whether in person or by proxy. For the purpose of calculating the "majority in number" requirement for the approval of the proposal, each registered shareholder, present and voting in person or by proxy, will be counted as a single shareholder, regardless of the number of shares voted by that shareholder. If a registered shareholder elects to vote a portion of such holder's Seagate-Cayman common shares in favor of the proposal, and a portion against the proposal, then, subject to any reasonable objection that may be raised, that registered shareholder will be counted as one shareholder voting in favor of the proposal and as one shareholder voting against the proposal, thereby

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effectively canceling out that registered shareholder's vote for the purposes of the "majority in number" calculation.

        The Capital Reduction Proposal must be approved by a majority of at least two thirds of the Seagate-Cayman common shares present and voting, whether in person or by proxy.

        The Distributable Reserves Proposal must be approved by more than 50% of all common shares present and voting, in person or by proxy, on the Distributable Reserves Proposal. Approval of the Distributable Reserves Proposal by our common shareholders is not a condition to the effectiveness of the Scheme of Arrangement, but the Board may determine not to proceed with the Transaction for any reason, including because the Distributable Reserves Proposal is not approved.

        The adjournment proposals, if presented, must be approved by more than 50% of all common shares present and voting, in person or by proxy.

        Because the quorum for the Special Scheme Meeting is the presence of at least two common shareholders and the quorum for the Extraordinary General Meeting is the presence in person or by proxy of shareholders holding a majority of the issued and outstanding Seagate-Cayman common shares, but for each proposal, the voting requirement is determined by the number of shareholders who are present and voting at the applicable Meeting, each of the proposals could be approved with the affirmative vote of less than 50% of the issued and outstanding Seagate-Cayman common shares.

Proxies

        General.    A proxy card is being sent to each Seagate-Cayman shareholder as of the record date. Shareholders of record can cast their votes by proxy by:

•

using the Internet or telephone to appoint proxies to cast their vote by following the instructions on the enclosed proxy card; or



•

completing, signing and returning the enclosed proxy card.

        The procedures for Internet appointment of a proxy are designed to authenticate the appointment of a proxy to cast shareholders' vote by use of a personal identification number. The procedures allow shareholders to appoint a proxy to vote their shares and to confirm that their instructions have been properly recorded. If you are a shareholder of record and you would like to appoint your proxy to vote by Internet, please refer to the specific instructions contained on the enclosed proxy card. If you appoint your proxy to vote by Internet, you do not need to return the enclosed proxy card. In order to be timely processed, an Internet appointment must be received by [*] on [*]. For more details about Internet proxies, please see "The Special Scheme Meeting and the Extraordinary General Meeting—How You Can Vote.

        To vote your shares directly, you may attend the meetings and cast your vote in person. If you hold your Seagate-Cayman shares in the name of a broker, depository or nominee, the broker, depository or nominee may generally vote your shares it holds in accordance with instructions received. Shareholders who hold their shares through a broker, depository or nominee must vote their shares in the manner prescribed by their broker. Therefore, please follow the instructions provided by your broker, depository or nominee when voting your Seagate-Cayman shares.

        Your broker, depository or nominee may not be able to vote your common shares unless the broker, depository or nominee receives appropriate instructions from you. Brokers, depositories or nominees who hold shares on behalf of customers have the authority to vote on "routine" proposals when they have not received instructions from beneficial owners, but are precluded from exercising their voting discretion with respect to proposals for "non-routine" matters. Proxies submitted by brokers, depositories or nominees without instructions from customers for these non-routine matters are referred to as "broker non-votes." We believe the Scheme of Arrangement Proposal, the Capital

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Reduction Proposal and the Distributable Reserves Proposal are proposals for non-routine matters, so it is important you follow your broker's, depository's or nominee's instructions and vote.

        Revocation.    You may revoke your proxy at any time before it is exercised at the Meetings in any of the following ways:

•

by notifying Seagate-Cayman Secretary in writing at: Company Secretary, c/o Office of the General Counsel, 920 Disc Drive, Scotts Valley, California 95066, which notice must be received no later than [*] on[*];



•

by submitting another properly signed proxy card with a later date or another Internet or telephone proxy at a later date, which proxy must be received no later than [*] on [*]; or



•

by voting in person at the applicable Meeting.

        Your proxy will not be revoked merely by attending the Special Scheme Meeting or the Extraordinary General Meeting. To revoke a proxy, you must take one of the actions described above. If you hold your Seagate-Cayman common shares in the name of a broker, depository or nominee, you should follow the instructions provided by your broker, depository or nominee in revoking your previously granted instructions.

Selected Historical Financial and Other Data

        The following table sets forth the selected historical consolidated financial data for Seagate-Cayman for each of the last five full fiscal years, which have been derived from our audited consolidated financial statements incorporated by reference into this proxy statement, after retrospective adjustment for the impact of a change in accounting for convertible debt instruments adopted in the first quarter of fiscal 2010. The selected historical consolidated financial data for Seagate-Cayman for the six month periods ended January 1, 2010 and January 2, 2009, have been derived from our unaudited condensed consolidated financial statements, and in the opinion of management, include all adjustments necessary to present fairly the consolidated financial position, results of operations, cash flows and shareholders' equity for the periods presented. Such adjustments are of a normal recurring nature.

        The selected historical financial data below should be read in conjunction with the consolidated financial statements and their accompanying notes and "Management's Discussion and Analysis of Financial Condition and Results of Operations" included in our Annual Report on Form 10-K for the fiscal year ended July 3, 2009 and Quarterly Report on Form 10-Q for the quarter ended January 1, 2010 and other financial information incorporated by reference herein. Historical financial information may not be indicative of Seagate-Ireland's future performance.

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        We have included no data for Seagate-Ireland because this entity was incorporated on January 22, 2010 and was not in existence during any of the periods shown below.

Unaudited Summary Pro Forma Financial Information

        Pro forma consolidated financial statements for Seagate-Ireland are not presented in this proxy statement because no significant pro forma adjustments are required to be made to show the impact of the Transaction to the statement of operations of Seagate-Cayman for the fiscal year ended July 3, 2009 and the six months ended January 1, 2010 or the balance sheet as of January 1, 2010. Those financial statements are included in Seagate-Cayman's Annual Report on Form 10-K for the fiscal year ended July 3, 2009 and Quarterly Report on Form 10-Q for the quarter ended January 1, 2010, respectively.

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RISK FACTORS

        Before you decide how to vote, you should consider carefully the following risk factors in addition to the other information contained in this proxy statement and the documents incorporated by reference, including, without limitation, our Annual Report on Form 10-K for the fiscal year ended July 3, 2009, our Quarterly Reports on Form 10-Q for the fiscal quarters ended October 1, 2009 and January 1, 2010 and our subsequent filings with the SEC.

Your rights as a shareholder will change as a result of the Transaction.

        Because of differences between Irish law and Cayman Islands law and differences between the governing documents of Seagate-Ireland and Seagate-Cayman, we are unable to adopt governing documents for Seagate-Ireland that are identical to the governing documents for Seagate-Cayman. We have attempted to preserve in memorandum and articles of association of Seagate-Ireland the same allocation of material rights and powers between the shareholders and our board of directors that exists under Seagate-Cayman's memorandum and articles of association. Nevertheless, Seagate-Ireland's proposed memorandum and articles of association differ from Seagate-Cayman's memorandum and articles of association, both in form and substance and your rights of a shareholder will change.

        For a description of these differences, please see the comparison chart of your rights as a common shareholder of Seagate-Cayman against your rights as an ordinary shareholder of Seagate-Ireland, located in "Comparison of Rights of Shareholders and Powers of the Board of Directors."

Our effective tax rate may increase whether we effect the Transaction or not.

        While the Transaction is not anticipated to have any material impact on our effective tax rate, there is uncertainty regarding the tax policies of the jurisdictions where we operate (which include the potential legislative actions described below), and our effective tax rate may increase and any such increase may be material. Additionally, the tax laws of Ireland and other jurisdictions could change in the future, and such changes could cause a material change in our effective tax rate.

Legislative and regulatory action could materially and adversely affect us regardless of whether or not we complete the Transaction.

        Our tax position could be adversely impacted by changes in the tax laws, tax treaties or tax regulations or the interpretation or enforcement thereof by any tax authority, regardless of whether we complete the Transaction. For example, legislative action may be taken by the U.S. Congress which, if ultimately enacted, could override tax treaties upon which we rely or could broaden the circumstances under which we would be considered a U.S. resident, which could materially and adversely affect our effective tax rate and cash tax position. We cannot predict the outcome of any specific legislative proposals. If proposals were enacted that had the effect of disregarding the Transaction or limiting our ability to take advantage of the tax treaties between Ireland and other jurisdictions (including the U.S.), we could be subjected to increased taxation. However, the tax consequences of any such proposals should be no worse for Seagate-Ireland than they would be for Seagate-Cayman if we had continued to maintain our place of incorporation in the Cayman Islands. In addition, any future amendments to the current income tax treaties between Ireland and the other jurisdictions (including the U.S.) could subject us to increased taxation.

        As a company incorporated in Ireland, an EU member state, Seagate-Ireland is subject to Irish and EU law and this could impose regulatory burdens on Seagate-Ireland in the future.

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The Transaction will result in additional direct and indirect costs, even if it is not completed.

        We will incur additional costs as a result of the Transaction, although we do not expect these costs to be material. Seagate-Ireland has been incorporated in Ireland and is subject to Irish law. Our intention is that we will hold a majority of our regularly scheduled board of directors meetings in Ireland, but we do not currently expect to hold our annual general meetings of shareholders in Ireland, nor do we plan to list Seagate-Ireland ordinary shares on the Irish Stock Exchange. We also expect to incur costs and expenses, including professional fees, to comply with Irish corporate and tax laws and financial reporting requirements. In addition, we expect to incur attorneys' fees, accountants' fees, filing fees, mailing expenses, proxy solicitation fees and financial printing expenses in connection with the Transaction, even if the Scheme of Arrangement is not approved or completed. The Transaction also may negatively affect us by diverting attention of our management and employees from our operating business during the period of implementation and by increasing other administrative costs and expenses.

We cannot provide any assurance that changes will not be made to the terms of our indenture governing the 10.00% senior secured second-priority notes due 2014 in connection with obtaining the supplemental indenture required or necessary for the Transaction.

        We expect to seek consents or waivers and enter into a supplemental indenture with respect to our existing indenture governing the 10.00% senior secured second-priority notes due 2014 under which Seagate-Ireland will guarantee the obligations of the issuer of such notes and assume the obligations of a parent entity under the indenture. One of the conditions to consummation of the Transaction is that Seagate-Ireland enter into a supplemental indenture, with respect to such indenture, on terms acceptable to us. Please see "Proposal Number One: The Scheme of Arrangement—Conditions to Consummation of the Transaction." Although we expect that no material change would be made to the terms of such indenture in connection with obtaining such supplemental indenture, we cannot guarantee that there would not be any such change. Please see "Proposal Number One: The Scheme of Arrangement—Supplemental Indentures."

We cannot provide any assurance that we will be able to obtain the necessary waivers or enter into an amendment to our credit agreement that will enable us to avoid technical defaults as a result of the Transaction.

        We are seeking waivers and an amendment to our credit agreement in order to avoid technical defaults as a result of the Transaction. The amendment will also provide that Seagate-Ireland will guarantee the obligations of the borrower under the credit agreement. One of the conditions to consummation of the Transaction is that we receive the necessary waivers and that we enter into an amendment to the credit agreement on terms acceptable to us. Please see "Proposal Number One: The Scheme of Arrangement—Conditions to Consummation of the Transaction." Although we expect to receive the necessary waivers and enter into an amendment prior to the Transaction Time, we can provide no assurance that the lenders will waive the technical defaults or enter into an amendment to the credit agreement on terms acceptable to us or at all. Please see "Proposal Number One: The Scheme of Arrangement—Credit Agreement." In the event that we are unable to receive the necessary waives or enter into an amendment on terms acceptable to us, we may be required to delay the Transaction or abandon it entirely.

We may choose to abandon or delay the Transaction.

        We may abandon or delay the Transaction at any time prior to the Transaction Time, even after the shareholders have approved the Transaction at the Special Scheme Meeting and the Extraordinary General Meeting and the Scheme of Arrangement has been sanctioned by the Cayman Court. While we currently expect to complete the Transaction as soon as practicable after obtaining shareholder

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approval of the Scheme of Arrangement at the meeting, our board of directors may delay the Transaction for a significant time or may abandon the Transaction altogether after the Meetings because, among other reasons, the Transaction is no longer in our best interest or the best interests of our shareholders or may not result in the benefits we expect, or our estimated cost of the Transaction increases. Additionally, we may not be able to obtain the requisite shareholder or court approvals. Furthermore, if the Distributable Reserves Proposal is not approved by the shareholders, the board of directors may choose to abandon the Transaction. Please see "Proposal Number One: The Scheme of Arrangement—Amendment, Termination or Delay."

If the shareholders of Seagate-Cayman do not approve the Distributable Reserves Proposal, Seagate-Ireland may not have sufficient distributable reserves to pay dividends (or to repurchase or redeem shares) following the Transaction. In addition, we can provide no assurance that Irish High Court approval of the creation of distributable reserves will be forthcoming.

        Under Irish law, dividends must be paid and share repurchases and redemptions must generally be funded out of "distributable reserves," which Seagate-Ireland will not have immediately following the Transaction Time. Please see "Description of Seagate Technology plc Share Capital—Dividends" and "—Share Repurchases, Redemptions and Conversions." If the Scheme of Arrangement is approved, shareholders of Seagate-Cayman also will be asked at the Extraordinary General Meeting to approve the reduction of share premium of Seagate-Ireland to allow the creation of distributable reserves of Seagate-Ireland (through the reduction of the share premium account of Seagate-Ireland), so that we may pay dividends and repurchase or redeem shares following the Transaction. The approval of the distributable reserves proposal is not a condition to the consummation of the Transaction. Accordingly, if the shareholders of Seagate-Cayman approve the Scheme of Arrangement, but do not approve the distributable reserves proposal, and the Transaction is consummated, Seagate-Ireland may not have sufficient distributable reserves to pay dividends or to repurchase or redeem shares following the Transaction, [including under the current share repurchase plans of Seagate-Cayman] until such time as Seagate-Ireland has created distributable reserves through the generation of future profits from its operations.

        In addition, the creation of distributable reserves requires the approval of the Irish High Court. Although we are not aware of any reason why the Irish High Court would not approve the creation of distributable reserves, the issuance of the required order is a matter for the discretion of the Irish High Court and there is no guarantee that such approval will be forthcoming. Even if the Irish High Court does approve the creation of distributable reserves, it may take substantially longer than we anticipate. Please see "Proposal Number Three: Creation of Distributable Reserves."

As a result of different shareholder voting requirements in Ireland relative to the Cayman Islands, we will have less flexibility with respect to certain aspects of capital management than we now have.

        Under Cayman Islands law, our directors may issue, without shareholder approval, any common shares authorized in our memorandum and articles of association that are not already issued. Under Irish law, the authorized share capital of Seagate-Ireland can be increased by an ordinary resolution of its shareholders and the directors may issue new ordinary or preferred shares up to a maximum amount equal to the authorized but un-issued share capital, without shareholder approval, once authorized to do so by the articles of association of Seagate-Ireland or by an ordinary resolution of the Seagate-Ireland shareholders. Additionally, subject to specified exceptions, Irish law grants statutory pre-emptive rights to existing shareholders to subscribe for new issuances of shares for cash, but allows shareholders to authorize the waiver of the statutory pre-emptive rights with respect to any particular allotment of shares. The authorization of the directors to issue shares and the authorization of the waiver of the statutory pre-emptive rights must both be renewed by the shareholders at least every five years and we cannot provide any assurance that these authorizations will always be approved, which could limit our

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ability to issue equity and thereby adversely affect the holders of our debt securities. While we do not believe that the differences between Cayman Islands law and Irish law relating to our capital management will have an adverse effect on us, situations may arise where the flexibility we now have in the Cayman Islands would have provided benefits to our shareholders. Please see "Comparison of Rights of Shareholders and Powers of the Board of Directors—Capitalization," "—Pre-emption Rights, Share Warrants and Share Options and "—Distributions and Dividends; Repurchases and Redemptions."

As a result of different shareholder voting requirements in Ireland relative to the Cayman Islands, we will have less flexibility with respect to our ability to amend our constituent documents than we now have.

        Under Cayman Islands law and our current memorandum and articles of association, our memorandum and articles of association may be amended by the vote of the holders of not less than two-thirds of the votes cast at a general meeting. Irish law requires a special resolution of 75% of the shareholder votes cast at a general meeting for any amendment to the memorandum and articles of association of Seagate-Ireland. As a result of this Irish law requirement, situations may arise where the flexibility we now have under Cayman Islands law would have provided benefits to our shareholders that will not be available in Ireland. Please see "Comparison of Rights of Shareholders and Powers of the Board of Directors—Amendment of Governing Documents."

After the Transaction, attempted takeovers of Seagate-Ireland will be subject to the Irish Takeover Rules and subject to review by the Irish Takeover Panel.

        Following the completion of the Transaction, we will become subject to the Irish Takeover Rules, under which the board of directors of Seagate-Ireland will not be permitted to take any action which might frustrate an offer for Seagate-Ireland ordinary shares once the board of directors has received an approach which may lead to an offer or has reason to believe an offer is imminent. Further, it could be more difficult for Seagate-Ireland to obtain shareholder approval for a merger or negotiated transaction after the Transaction because the shareholder approval requirements for certain types of transactions differ, and in some cases are greater, under Irish law than under Cayman Islands law. Please see "Comparison of Rights of Shareholders and Powers of the Board of Directors—Capitalization," "—Pre-emption Rights, Share Warrants and Share Options" and "—Distributions and Dividends; Repurchases and Redemptions."

After the Transaction, a future transfer of your Seagate-Ireland shares may be subject to Irish stamp duty.

        In certain circumstances, the transfer of shares in an Irish incorporated company will be subject to Irish stamp duty which is a legal obligation of the buyer. This duty is currently at the rate of 1% of the price paid or the market value of the shares acquired, if higher. However, transfers of book-entry interests in DTC representing Seagate-Ireland shares should not be subject to Irish stamp duty. Accordingly, transfers by shareholders who hold their Seagate-Ireland ordinary shares beneficially through brokers which in turn hold those shares through DTC, should not be subject to Irish stamp duty on transfers to holders who also hold through DTC. This exemption is available because our shares are traded on a recognized stock exchange in the U.S.

        In relation to any transfer of Seagate-Ireland shares that is subject to Irish stamp duty, Seagate-Ireland's articles of association allow Seagate-Ireland, in its absolute discretion, to create an instrument of transfer and pay (or procure the payment of) any stamp duty payable by a buyer. In the event of any such payment, Seagate-Ireland is (on behalf of itself or its affiliates) entitled to (i) seek reimbursement from the buyer or seller (at its discretion), (ii) set-off the amount of the stamp duty against future dividends payable to the buyer or seller (at its discretion), and (iii) claim a lien against the Seagate-Ireland shares on which it has paid stamp duty. Parties to a share transfer may assume that any stamp

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duty arising in respect of a transaction in Seagate-Ireland shares has been paid unless one or both of such parties is otherwise notified by us.

Dividends received by you may be subject to Irish dividend withholding tax.

        In certain circumstances, as an Irish tax resident company, we are required to deduct Irish dividend withholding tax (currently at the rate of 20%) from dividends paid to our shareholders. Shareholders resident in the U.S., EU member states (other than Ireland), or other countries with which Ireland has signed a tax treaty (whether the treaty has been ratified or not) (as set forth in Annex C) generally should not be subject to Irish withholding tax so long as the shareholder has provided its broker, for onward transmission to Seagate-Ireland's qualifying intermediary (or other designated agent) (in the case of shares held beneficially), or Seagate-Ireland or its transfer agent (in the case of shares held directly), with all the necessary documentation prior to payment of the dividend. However, some shareholders may be subject to withholding tax, which could adversely affect the price of our shares. Please see "Material Tax Considerations Relating to the Transaction—Irish Tax Considerations—Withholding Tax on Dividends."

Dividends received by you could be subject to Irish income tax.

        Dividends paid in respect of our shares will generally not be subject to Irish income tax where the beneficial owner of these dividends is exempt from dividend withholding tax, unless the beneficial owner of the dividend is resident or ordinarily resident in Ireland for Irish tax purposes or the shareholder holds shares in connection with a trade carried on by such shareholder in Ireland through a branch or agency.

        Seagate-Ireland shareholders who receive their dividends subject to Irish dividend withholding tax will generally have no further liability to Irish income tax on the dividend unless the beneficial owner of the dividend is resident or ordinarily resident in Ireland for Irish tax purposes or the shareholder holds such shares in connection with a trade carried on by such holder in Ireland through a branch or agency. Please see "Material Tax Considerations Relating to the Transaction—Irish Tax Considerations—Income Tax on Dividends Paid on Seagate-Ireland Shares."

        Seagate recommends that each shareholder consult his or her own tax advisor as to the tax consequences of holding shares in and receiving dividends from Seagate-Ireland.

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PROPOSAL NUMBER ONE: THE SCHEME OF ARRANGEMENT

Overview

        As explained in more detail below, the Scheme of Arrangement on which we are asking you to vote, in connection with the other steps of the Transaction described in this proxy statement, will effectively change our place of incorporation from the Cayman Islands to Ireland. The Scheme of Arrangement Proposal is conditioned upon the approval of the capital reduction in Proposal Number Two. The Transaction can not occur without the approval of both Proposal Number One and Proposal Number Two.

        The Transaction involves several steps. On December 14, 2009, the board of directors of Seagate-Cayman held a board meeting in Dublin, Ireland to, among other things, discuss a potential transaction to change the place of incorporation of Seagate-Cayman. On January 22, 2010, Seagate-Cayman, the Cayman Islands company whose common shares you currently own, formed Seagate-Ireland as a direct subsidiary. On January 27, 2010, the board of directors of Seagate-Cayman held a board meeting in Dublin, Ireland to, among other things, approve the Transaction and the Scheme of Arrangement. On [*], we petitioned the Cayman Court to order, among other things, the calling of the Special Scheme Meeting to approve the Scheme of Arrangement. We will hold the Special Scheme Meeting to approve the Scheme of Arrangement and the EGM on [*], 2010. If we obtain the necessary shareholder approvals, the Cayman Court will hold the Sanction Hearing, which is expected to be held on [*], 2010, to sanction the Scheme of Arrangement and confirming the associated capital reduction. Assuming we receive the necessary approvals from Seagate-Cayman's shareholders and the Cayman Court and the conditions to consummate the Transaction are satisfied (and we do not abandon the Transaction), we will file the court order sanctioning the Scheme of Arrangement with the Cayman Islands Registrar of Companies, at which time the Scheme of Arrangement will be effective on its terms. Various steps of the Transaction will effectively occur simultaneously at the Transaction Time, which we anticipate will be after the close of trading on NASDAQ on the day the Scheme of Arrangement becomes effective, which we expect to be [*], and before the opening of trading on NASDAQ on the next business day.

        At the Transaction Time, the following steps of the Transaction will effectively occur simultaneously:

•

all issued and outstanding Seagate-Cayman common shares shall be cancelled and shall cease to exist;



•

Seagate-Ireland will issue ordinary shares on a one-for-one basis to the holders of Seagate-Cayman common shares for each Seagate-Cayman common share that has been cancelled;



•

in consideration for the issuance by Seagate-Ireland of its ordinary shares to the Seagate-Cayman common shareholders as set forth in the second bullet above, Seagate-Cayman will allot and issue a number of fully-paid Seagate-Cayman common shares to Seagate-Ireland that is equal to the number of Seagate-Ireland ordinary shares issued to the holders of Seagate-Cayman common shares that were cancelled as set forth in the first bullet above; and



•

pursuant to the Merger Scheme, Seagate-Cayman will merge with merger sub, Seagate-Cayman will survive the merger, merger sub will be dissolved and will cease to exist and Seagate-Cayman will become a direct, wholly-owned subsidiary of Seagate-Ireland, the resulting publicly traded parent of the Seagate group of companies. Holders of common shares in Seagate-Cayman will not be required to vote in connection with the Merger Scheme.

        If, and only if, the Scheme of Arrangement and the Merger Scheme are effected, an election will be made to treat Seagate-Cayman as a disregarded entity for U.S. federal income tax purposes, effective shortly after the Transaction Time.

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        All previously outstanding ordinary shares of Seagate-Ireland, which prior to the Transaction Time will be held by Seagate-Cayman and its nominees, will be acquired by Seagate-Ireland for no consideration and cancelled in accordance with a resolution passed by Seagate-Cayman and the other current shareholders of Seagate-Ireland.

        As a result of the Transaction, the common shareholders of Seagate-Cayman will become shareholders of Seagate-Ireland, and Seagate-Cayman will become a wholly-owned subsidiary of Seagate-Ireland.

        In connection with the completion of the Transaction, Seagate-Ireland will assume, on a one-for-one basis, Seagate-Cayman's existing obligations in connection with awards granted under Seagate-Cayman's equity incentive plans and other similar equity awards. Seagate-Ireland will also assume the obligations of Seagate-Cayman as a guarantor under certain of the indentures governing our outstanding notes and our credit agreement and will assume the obligations of a parent entity under the indentures. In addition, any securities issued by Seagate-Cayman or its subsidiaries that are convertible, exchangeable or exercisable into common shares of Seagate-Cayman will become convertible, exchangeable or exercisable, as the case may be, into ordinary shares of Seagate-Ireland on a one-for-one basis.

        As of the Record Date, [*] common shares of Seagate-Cayman were issued and outstanding and we had [      ] shareholders of record.

        There currently are no fractional shares held of record and we do not expect there to be any such fractional shares held of record immediately prior to the Transaction Time.

Background and Reasons for the Transaction

        We have been incorporated in the Cayman Islands since August 10, 2000. While our tenure in the Cayman Islands has served us and our shareholders well, the board of directors has had cause to revisit the decision regarding the location of our place of incorporation.

        There continues to be negative publicity regarding, and criticism of, companies that conduct business in the U.S. but are domiciled in countries that have low rates of, or no direct taxation and as a consequence do not have a substantial network of double taxation (or similar) treaties with the U.S. or with many of countries where we have operations. Furthermore, legislative and regulatory bodies in various jurisdictions, including the U.S., have actively considered proposals and/or introduced legislation that, if enacted, could increase our tax burden if we remained incorporated in the Cayman Islands. For example, recent legislative proposals could broaden the circumstances under which we would be considered a U.S. resident or could override certain tax treaties and limit the treaty benefits on certain payments by our U.S. subsidiaries to our non-U.S. affiliates. Consequently, following a thorough review, we have determined that moving our place of incorporation out of the Cayman Islands [will reduce those risks and] is best for Seagate-Cayman, our shareholders, our employees and other stakeholders.

        After considering various factors and reviewing a number of different countries, our board of directors determined that it was advisable to change the jurisdiction of incorporation of the parent company of the Seagate group to Ireland. Our board of directors' determination that Ireland is the preferred choice for the domicile of the parent of the Seagate group was based on many factors, including the following:

•

Ireland has strong international relationships as a member of the European Union ("EU") and a long history of international investment and long-established commercial relationships, trade agreements and tax treaties with the other EU member states, the U.S. and other countries around the world where we do business. Ireland is also a founding member of the OECD. As a result, we believe Ireland offers a stable long-term legal and regulatory environment with the financial and legal infrastructure to meet our needs;

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•

Ireland is an English-speaking common law jurisdiction, which we believe makes its legal system less prescriptive and more flexible than those of civil law jurisdictions and also more familiar to Seagate and its shareholders;



•

Ireland has a stable and well-developed legal system which we believe encourages high standards of corporate governance and provides shareholders with substantial rights. We believe that the perception of an Irish company among regulatory authorities, investors, creditors and customers is highly favorable;



•

Ireland as a member of the EU will enable favorable EU tax directives and other protections to apply to us;



•

Ireland permits the payment of dividends in U.S. Dollars;



•

Ireland's taxation system and large double taxation network will enable us to maintain a competitive worldwide effective corporate tax rate; and



•

Ireland is the only English-speaking member of the eurozone.

        As a result of these factors, our board of directors determined that it was advisable to effect the Transaction. We cannot assure you that the anticipated benefits of the Transaction will be realized. In addition to the potential benefits described above, the Transaction will expose you and us to some risks. Please see the discussion under "Risk Factors."

        Our board of directors has considered both the potential advantages of the Transaction and these risks and has approved the Scheme of Arrangement and recommends that the shareholders vote for the Scheme of Arrangement.

Amendment, Termination or Delay

        The Scheme of Arrangement may be amended, modified or supplemented at any time before or after its adoption by the common shareholders of Seagate-Cayman at the Special Scheme Meeting. However, after adoption, no amendment, modification or supplement may be made or effected that legally requires further approval by Seagate-Cayman shareholders without obtaining such approval.

        At the Sanction Hearing, the Cayman Court may impose such conditions as it deems appropriate in relation to the Scheme of Arrangement, but may not impose any material changes without the joint consent of Seagate-Cayman and Seagate-Ireland. Seagate-Cayman may, subject to U.S. securities law constraints, consent to any modification of the Scheme of Arrangement on behalf of the shareholders which the Cayman Court may think fit to approve or impose.

        The board of directors of Seagate-Cayman may terminate the Scheme of Arrangement and abandon the Transaction, or delay the Transaction, at any time prior to the Transaction Time, without obtaining the approval of Seagate-Cayman shareholders, even though the Scheme of Arrangement may have been approved by such shareholders and sanctioned by the Cayman Court and all other conditions to the Transaction may have been satisfied, if the board of directors determines that such course is in our best interests and the best interests of our shareholders.

        Unless the Scheme of Arrangement has become effective and the Transaction Time has occurred on or before [**], or such later date, if any, as Seagate-Cayman may agree and the Cayman Court may allow, the Scheme of Arrangement will lapse by its terms and not come into effect and therefore, the Transaction will not be effected.

Conditions to Consummation of the Transaction

        It is anticipated that the Transaction Time will be after the close of trading on NASDAQ on the day the Scheme of Arrangement becomes effective, which we expect to be [*], and before the opening

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of trading on NASDAQ on the next business day, but it may be on an earlier or later date if all conditions to the consummation of the Transaction are satisfied or, if allowed by law, waived. The Transaction will not be completed unless, among other things, the following conditions are satisfied or, if allowed by law, waived:

•

a definitive version of this proxy statement has been filed with the SEC;



•

the Scheme of Arrangement is approved by the requisite vote of the shareholders of Seagate-Cayman at the Special Scheme Meeting;



•

the Capital Reduction Proposal is approved by the requisite vote of the shareholders of Seagate-Cayman at the Extraordinary General Meeting;



•

the requisite court order sanctioning the Scheme of Arrangement and confirming the capital reduction is obtained from the Cayman Court, and is duly lodged with the Cayman Islands Registrar of Companies;



•

there is no threatened, pending or effective decree, order, injunction or other legal restraint prohibiting the consummation of the Scheme of Arrangement or related transactions;



•

the Seagate-Ireland shares to be issued pursuant to the Transaction are authorized for listing on the NASDAQ, subject to official notice of issuance;



•

all consents and governmental authorizations that are necessary, desirable or appropriate in connection with the Scheme of Arrangement and related transactions (including, without limitation, consents or waivers and/or the entering into of supplemental indentures with respect to the indentures) are obtained on terms acceptable to Seagate-Cayman and are in full force and effect;



•

all conditions precedent for the effective implementation of the Merger-Sub Scheme have been satisfied or, to the extent permitted by law, waived;



•

Seagate-Cayman receives an opinion from Baker & McKenzie LLP, in form and substance reasonably satisfactory to it, confirming, as of the Transaction Time, the matters discussed under "Material Tax Considerations Relating to the Transaction—U.S. Federal Income Tax Considerations;"



•

Seagate-Cayman receives an opinion from Arthur Cox, in form and substance reasonably satisfactory to it, confirming, as of the Transaction Time, the matters discussed under "Material Tax Considerations Relating to the Transaction—Irish Tax Considerations;"



•

the approval of the requisite holders of the 10.00% senior secured second-priority notes due 2014 issued by Seagate Technology International of a supplemental indenture that would permit the Transaction; and



•

waivers and amendments to the Second Amended and Restated Credit Agreement, dated as of April 3, 2009, among Seagate-Cayman, Seagate Technology HDD Holdings, as borrower, and the lenders and agents party thereto have been obtained, which waivers and amendments address and cure any defaults that would otherwise result from the Transaction.

Court Sanction of the Scheme of Arrangement

        Pursuant to Section 86 of the Companies Law (2009 Revision) of the Cayman Islands (the "Cayman Islands Companies Law"), the Scheme of Arrangement must be sanctioned by the court in the Cayman Islands. This requires Seagate-Cayman to file a petition (the "Petition") for the Scheme of Arrangement with the Cayman Court. Prior to the mailing of this proxy statement, Seagate-Cayman obtained directions from the Cayman Court providing for the convening of a meeting of

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Seagate-Cayman's shareholders and other procedural matters regarding the meeting and the further conduct of the Petition, including a date upon which the Cayman Court will hear the Petition. A copy of the Cayman Court's order is attached as Annex D to this proxy statement. Subject to the common shareholders of Seagate-Cayman approving the Scheme of Arrangement with the vote required by the Cayman Islands Companies Law, a Sanction Hearing will be required to hear the Petition and sanction the Scheme of Arrangement and confirm the associated capital reduction. At the Sanction Hearing, the Cayman Court may impose such conditions as it deems appropriate in relation to the Scheme of Arrangement, but may not impose any material changes without the joint consent of Seagate-Cayman and Seagate-Ireland. Seagate-Cayman may, subject to U.S. securities law constraints, consent to any modification of the Scheme of Arrangement on behalf of the shareholders which the Cayman Court may think fit to approve or impose. In determining whether to exercise its discretion and sanction the Scheme of Arrangement, the Cayman Court will determine, among other things, whether the Scheme of Arrangement is fair to Seagate-Cayman's shareholders. We expect the Sanction Hearing to be held on [*], 2010 at the Cayman Court in George Town, Grand Cayman, Cayman Islands. If you are a common shareholder who wishes to appear in person or by counsel at the Sanction Hearing and present evidence or arguments in support of or in opposition to the Scheme of Arrangement, you may do so. In addition, the Cayman Court has wide discretion to hear from interested parties. Seagate-Cayman will not object to the participation in the Sanction Hearing by any beneficial holder of common shares who holds shares through a custodian, depository, nominee or broker. In accordance with its terms, the Scheme of Arrangement will become effective on its terms as soon as a copy of the Order of the Cayman Court sanctioning the Scheme of Arrangement has been delivered to the Registrar of Companies of the Cayman Islands for registration as required by Section 86 of the Cayman Islands Companies Law, although on the terms of the Scheme, the Transaction does not take effect until that and a number of other conditions precedent are satisfied or waived. Please see above under the caption "—Conditions to Consummation of the Transaction" for more information on the conditions to the Transaction.

        At the Special Scheme Meeting, Seagate-Cayman's shareholders will be asked to approve the Scheme of Arrangement, substantially in the form attached as Annex A to this proxy statement. If the shareholders approve the Scheme of Arrangement, then Seagate-Cayman will apply for sanction of the Scheme of Arrangement at the Sanction Hearing. We encourage you to read the Scheme of Arrangement in its entirety for a complete description of its terms and conditions.

        Once the Scheme of Arrangement is effective, the Cayman Court will have exclusive jurisdiction to hear and determine any suit, action or proceeding and to settle any dispute which arises out of or is connected with the terms of the Scheme of Arrangement or its implementation or out of any action taken or omitted to be taken under the Scheme of Arrangement or in connection with the administration of the Scheme of Arrangement. A common shareholder who wishes to enforce any rights under the Scheme of Arrangement after such time must notify Seagate-Cayman in writing of its intention at least five business days prior to commencing a new proceeding. After the Transaction Time, no shareholder may commence a proceeding against Seagate-Ireland or Seagate-Cayman in respect of or arising from the Scheme of Arrangement except to enforce its rights under the Scheme of Arrangement where a party has failed to perform its obligations under the Scheme of Arrangement.

        When under any provision of the Scheme of Arrangement a matter is to be determined by Seagate-Cayman, then Seagate-Cayman will have discretion to interpret those matters under the Scheme of Arrangement in a manner that it considers fair and reasonable, and its decisions will be binding on all concerned.

Federal Securities Law Consequences; Resale Restrictions

        The issuance of Seagate-Ireland ordinary shares to Seagate-Cayman shareholders in connection with the Transaction will not be registered under the Securities Act of 1933 (the "Securities Act").

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Section 3(a)(10) of the Securities Act exempts securities issued in exchange for one or more outstanding securities from the general requirement of registration where the terms and conditions of the issuance and exchange of such securities have been approved by any court of competent jurisdiction, after a hearing upon the fairness of the terms and conditions of the issuance and exchange at which all persons to whom such securities will be issued have a right to appear and to whom adequate notice of the hearing has been given. In determining whether it is appropriate to authorize the Scheme of Arrangement, the Cayman Court will consider at the Sanction Hearing whether the terms and conditions of the Scheme of Arrangement are fair to Seagate-Cayman shareholders. The Cayman Court has fixed the date and time for the Sanction Hearing, which will be held at the Cayman Court in George Town, Grand Cayman, Cayman Islands, on [*], 2010. The Seagate-Ireland ordinary shares issued to Seagate-Cayman shareholders in connection with the Transaction will be freely transferable, except for the ability of the director of Seagate-Ireland to decline the registration of shares in limited circumstances and for restrictions applicable to certain "affiliates" of Seagate-Cayman under the Securities Act, as follows:

•

Persons who were not affiliates of Seagate-Cayman at the Transaction Time and have not been affiliates within 90 days prior to such time will be permitted to sell any Seagate-Ireland ordinary shares received in the Transaction without regard to Rule 144 under the Securities Act.



•

Persons who were affiliates of Seagate-Cayman at the Transaction Time or were affiliates within 90 days prior to such time will be permitted to resell any Seagate-Ireland ordinary shares they receive pursuant to the Transaction in the manner permitted by Rule 144. In computing the holding period of the Seagate-Ireland ordinary shares for the purposes of Rule 144(d), such persons will be permitted to "tack" the holding period of their Seagate-Cayman shares held prior to the Transaction Time.



•

Persons whose shares of Seagate-Cayman bear a legend restricting transfer will receive shares of Seagate-Ireland that are subject to the same restrictions.

        Persons who may be deemed to be affiliates of Seagate-Cayman and Seagate-Ireland for these purposes generally include individuals or entities that control, are controlled by, or are under common control with, Seagate-Cayman or Seagate-Ireland, and would generally not be expected to include shareholders who are not executive officers, directors or significant shareholders of Seagate-Cayman or Seagate-Ireland.

        We have not filed a registration statement with the SEC covering any resales of the Seagate-Ireland ordinary shares to be received by Seagate-Cayman's shareholders in connection with the Transaction. Seagate-Ireland intends to file certain post-effective amendments to existing effective registration statements of Seagate-Cayman concurrently with the completion of the Transaction.

        Upon consummation of the Transaction, the ordinary shares of Seagate-Ireland will be deemed to be registered under Section 12(b) of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), by virtue of Rule 12g-3 under the Exchange Act, without the filing of any Exchange Act registration statement.

Effective Date and Transaction Time

        If the Scheme of Arrangement is approved by the requisite shareholder majorities and sanctioned by the Cayman Court and the other conditions to the consummation of the Transaction are satisfied (and we do not abandon the Transaction), the Scheme of Arrangement will become effective on its terms upon our filing of the court order sanctioning the Scheme of Arrangement with the Registrar of Companies in the Cayman Islands. Please see "Proposal Number One: The Scheme of Arrangement—Conditions to Consummation of the Transaction." Various steps of the Transaction will occur effectively simultaneously at the Transaction Time, which we anticipate will be after the close of trading on

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NASDAQ on the day the Scheme of Arrangement becomes effective, which we expect to be [*], and before the opening of trading on NASDAQ on the next business day, but may be at such earlier or later date and time as the board of directors of Seagate-Cayman (or their duly authorized officer) determines. The expected timetable for the Transaction is set forth in Annex E to this proxy statement.

        In the event the conditions to the Transaction are not satisfied, the Transaction may be abandoned or delayed, even after approval by the Seagate-Cayman shareholders, the sanction of the Cayman Court and the lodgment of the court order with the Cayman Islands Registrar of Companies. In addition, the Transaction may be abandoned or delayed by our board of directors at any time prior to the Transaction Time, without obtaining the approval of the Seagate-Cayman shareholders, even though the Scheme of Arrangement may have been approved by Seagate-Cayman's shareholders and sanctioned by the Cayman Court and all other conditions to the Transaction may have been satisfied. Please see "Proposal Number One: The Scheme of Arrangement—Amendment, Termination or Delay."

Management of Seagate-Ireland

        When the Transaction is completed, the executives and directors of Seagate-Cayman immediately prior to the completion of the Transaction will be the executives and directors of Seagate-Ireland. Seagate-Ireland's memorandum and articles of association, as they will be in effect after the Transaction, provide for a single class of directors, just as Seagate-Cayman currently has, and Seagate-Ireland's directors will be subject to re-election at the 2010 annual general meeting of Seagate-Ireland.

Indemnification Agreements

        Seagate-Cayman's articles of association require it to indemnify, to the fullest extent permitted by law, any director, alternate director, officer or trustee acting in relation to any of the affairs of the company against all liabilities incurred or suffered by such person as a director or officer, including the costs of defending any proceedings (including civil, criminal, investigative or administrative proceedings), provided that they are not indemnified for any liability arising from (a) their own fraud or dishonesty, (b) their own conscious, intentional or willful breach of their obligation to act honestly; or (c) any claim to recover gain, personal profit or other advantage to which the director or offices is not legally entitled. Seagate-Cayman's articles of association also require Seagate-Cayman to pay reasonable expenses incurred in a proceeding in advance of the final disposition of any such proceeding, provided that the indemnified person undertakes to repay Seagate-Cayman if it is ultimately determined that such person was not entitled to indemnification. In addition, Seagate-Cayman has entered into indemnification agreements with each of its directors and executive officers.

        Seagate-Ireland's memorandum and articles of association contain similar indemnification and expense advancement provisions in favor of the officers of Seagate-Ireland other than the directors and the Secretary. The scope of the indemnification provided to Seagate-Ireland's directors and Secretary set forth in Seagate-Ireland's memorandum and articles of association is limited in accordance with the Irish Companies Acts. For information on the limitations on the ability of an Irish company to indemnify its directors or its Secretary, please see "Comparison of Rights of Shareholders and Powers of the Board of Directors—Indemnification of Directors and Officers; Insurance."

        In addition, due to more restrictive provisions of Irish law in relation to the indemnification of directors and the Secretary, in connection with the Transaction, we expect that Seagate-Cayman will continue to be a party to an indemnification agreement (or a deed poll indemnity) with or as to each of Seagate-Ireland's directors and certain officers, as well as with individuals serving as directors or officers of our subsidiaries. The current indemnification agreements between Seagate-Cayman and its officers and directors provide for the indemnification of, and advancement of expenses to, these persons. We expect and intend that the indemnification and expense advancement to be provided to directors and certain officers of Seagate-Ireland under the indemnification agreement (or deed poll

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indemnity) will be the same or substantially similar to that afforded in the current indemnification agreements between Seagate-Cayman and its officers and directors.

        Please see "Comparison of Rights of Shareholders and Powers of the Board of Directors—Indemnification of Directors and Officers; Insurance."

Interests of Certain Persons in the Transaction

        Pursuant to the terms of the equity awards granted to Seagate-Cayman directors under our 2004 Stock Compensation Plan, in connection with a change of control, which we believe includes the Transaction, such directors of Seagate-Cayman are entitled to full acceleration of such equity awards. However, at the time the awards were granted, we did not intend for the awards to accelerate in a transaction such as the Transaction where there is no actual change in control of the company and the directors and officers will remain the same following the Transaction. Accordingly, the directors have each voluntarily agreed to waive the acceleration of their equity awards in connection with the Transaction.

        Except for the indemnification arrangements and the acceleration of the equity awards (which has been waived in full by each director) described above, no person who has been a director or executive officer of Seagate-Cayman at any time since the beginning of the last fiscal year, or any associate of any such person, has any substantial interest in the Transaction, except for any interest arising from his or her ownership of securities of Seagate. No such person is receiving any extra or special benefit not shared on a pro rata basis by all other holders of common shares of Seagate-Cayman.

Regulatory Matters

        Other than the Scheme of Arrangement, we are not aware of any other governmental approvals or actions that are required to complete the Transaction other than compliance with U.S. federal and state securities laws and Cayman Islands and Irish corporate law. We do not believe that any significant regulatory approvals will be required to effect the Transaction.

No Appraisal Rights

        Under Cayman Islands law, none of the common shareholders of Seagate-Cayman has any dissenters' rights or right to an appraisal of the value of their shares or receive payment for them in connection with the Transaction.

No Action Required to Cancel Seagate-Cayman Common Shares and Receive Seagate-Ireland Ordinary Shares

        Assuming the Transaction becomes effective, your Seagate-Cayman shares will be cancelled and Seagate-Ireland ordinary shares will be issued to you without any action on your part, regardless of whether you currently hold Seagate-Cayman common shares in certificated form. All of Seagate-Ireland's shares will be issued in uncertificated book-entry form. Consequently, if you currently hold Seagate-Cayman shares in certificated form, following the Transaction, your share certificates will cease to have effect as documents or evidence of title and you may disregard such certificates. The transfer agent will make an electronic book-entry in your name and will mail you a statement evidencing your ownership of Seagate-Ireland shares.

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Dividend Policy

        Seagate-Cayman has not paid a dividend since February 20, 2009. Since the closing of our initial public offering in December 2002 Seagate-Cayman has paid dividends totaling approximately $952 million in the aggregate. The following are dividends paid in the last two fiscal years:

However, on April 13, 2009, Seagate-Cayman announced that it had adopted a policy of no longer paying a quarterly dividend to its common shareholders to enhance liquidity. We do not expect to resume paying dividends for the foreseeable future.

        Please see "Market Price and Dividend Information." Future dividends, if any, on the Seagate-Cayman common shares and/or Seagate-Ireland ordinary shares will be at the discretion of our board of directors and will depend on, among other things, our results of operations, cash requirements and surplus, financial condition, contractual restrictions and other factors that the board of directors may deem relevant, as well as our ability to pay dividends in compliance with Cayman Islands or Irish law, as applicable.

        Under Irish law, dividends must be paid out of "distributable reserves," which Seagate-Ireland will not have immediately following the Transaction Time but which we are taking steps to create. Please see "Risk Factors," "Description of Seagate Technology plc Share Capital—Dividends" and "Proposal Number Three: Creation of Distributable Reserves."

        For a description of the Irish tax rules relating to dividends, please see "Material Tax Considerations Relating to the Transaction—Irish Tax Considerations."

Equity Plans

        If the Transaction is completed, Seagate-Ireland will assume and adopt Seagate-Cayman's existing rights and obligations in connection with awards granted under Seagate-Cayman's equity incentive plans and other similar employee awards. To the extent Seagate-Cayman currently sponsors those equity incentive plans, then as of the Transaction Time, Seagate-Ireland will become the sponsor of the assumed equity incentive plans. The plans will be amended as necessary to give effect to the Transaction, including to provide (1) for the assumption and adoption by Seagate-Ireland of the applicable equity incentive plans and the various rights, duties or obligations thereunder; (2) that ordinary shares of Seagate-Ireland will be issued, held, available or used to measure benefits as appropriate under the plans, in lieu of common shares of Seagate-Cayman, including upon exercise of any options or upon vesting of restricted share units issued under those plans on a one-for-one basis; and (3) for the appropriate substitution of Seagate-Ireland for Seagate-Cayman in those plans. Shareholder approval of the Transaction will also constitute shareholder approval of the adoption and assumption of the equity incentive plans by Seagate-Ireland as contemplated by this proxy statement.

        Holders of outstanding options, restricted share units or other equity-based awards may be subject to tax as a result of the conversion of the underlying Seagate-Cayman common shares to Seagate-Ireland ordinary shares as of the Transaction Time, depending on the country where the holders are citizens or tax residents or the country where they resided during the life of such equity awards. In

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general, however, U.S. taxpayers should not recognize ordinary income at the time Seagate-Ireland assumes their equity awards. Tax withholding and/or reporting may be required by Seagate-Ireland or one of its affiliates and/or the holder of the applicable equity award, and certain employer social insurance contributions or other taxes may be due as a result of the conversion of the equity awards. Depending on the country where the holders are citizens or residents or the country where they resided during the life of the Seagate-Cayman awards, the conversion of equity awards may trigger certain regulatory filings or notices to employees concerning the tax or regulatory consequences of the Transaction.

Stock Exchange Listing

        Seagate-Cayman's common shares are currently listed on the NASDAQ. There is currently no established public trading market for the ordinary shares of Seagate-Ireland. We intend to file an application so that, immediately following the Transaction Time, the ordinary shares of Seagate-Ireland will be listed on the NASDAQ under the symbol "STX," the same symbol under which the Seagate-Cayman common shares are currently listed. At the present time, we do not plan for Seagate-Ireland's ordinary shares to be listed on the Irish Stock Exchange.

Accounting Treatment of the Transaction

        Under U.S. GAAP, the Transaction represents a transaction between entities under common control. Assets and liabilities are transferred at carrying value between entities under common control. Accordingly, the assets and liabilities of Seagate-Ireland will be reflected at the same carrying amounts as in the accounts of Seagate-Cayman at the Transaction Time.

Supplemental Indentures

        In connection with the Transaction, we expect Seagate-Ireland to seek consents or waivers and enter into a supplemental indenture to the indenture governing the 10.00% senior secured second-priority notes due 2014 issued by Seagate Technology International. We expect the supplemental indenture will provide that Seagate-Ireland will guarantee the obligations of the issuer and assume the obligations of the parent entity under such indenture. Additionally, we expect Seagate-Ireland to enter into supplemental indentures to the indentures governing the following notes issued by current subsidiaries of Seagate Cayman: (i) the 2.375% Convertible Senior Notes due 2012 issued by Seagate Technology (US) Holdings, Inc. ("STUS"), 5.75% convertible subordinated debentures due 2012 issued by STUS and the 6.8% convertible senior secured notes due 2010 issued by STUS. Similarly, we expect the supplemental indentures will provide that Seagate-Ireland will guarantee the obligations of the issuer and assume the obligations of the parent entity under such indentures.

        One of the conditions to consummation of the Transaction is that we obtain consents or waivers and enter into a supplemental indenture, with respect to the indenture governing the 10.00% senior secured second-priority notes due 2014 issued by Seagate Technology International, on terms acceptable to us. Please see "Proposal Number One: The Scheme of Arrangement—Conditions to Consummation of the Transaction." Although we expect that no material change would be made to the terms of such indenture in connection with entering into such supplemental indenture, we cannot guarantee that there would not be any such change.

Credit Facility

        We are seeking waivers and an amendment to our credit agreement in order to avoid technical defaults that would otherwise result from the Transaction. We expect that the amendment will also provide that Seagate-Ireland will guarantee the obligations of the borrower under our credit agreement.

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Effect of the Transaction on Potential Future Status as a Foreign Private Issuer

        Upon completion of the Transaction, we will remain subject to SEC reporting requirements, the mandates of the Sarbanes-Oxley Act and the corporate governance rules of the NASDAQ, and we will continue to report our consolidated financial results in U.S. dollars and in accordance with U.S. GAAP. We will also comply with any additional reporting requirements of Irish law.

        Seagate-Cayman currently is not a "foreign private issuer" within the meaning of the rules promulgated under the Exchange Act, and we do not currently believe that Seagate-Ireland will qualify as a "foreign private issuer" upon completion of the Transaction. The definition of a "foreign private issuer" has two parts—one based on a company's percentage of U.S. resident shareholders and the other on its business contacts with the U.S. An organization incorporated under the laws of a foreign country qualifies as a foreign private issuer unless both parts of the definition are satisfied as of the last business day of its most recently completed second fiscal quarter. We believe Seagate-Cayman currently satisfies the shareholder test because more than 50% of our outstanding voting securities are held by U.S. residents, and we currently expect that Seagate-Ireland will meet the shareholder test upon the completion of the Transaction. The business contacts test requires that any of the following be true with respect to the organization incorporated under the laws of a foreign country: (i) the majority of its executive officers or directors are U.S. citizens or residents; (ii) more than 50% of its assets are located in the U.S.; or (iii) its business is administered principally in the U.S. Seagate-Cayman currently meets the business contacts test, and we currently expect that Seagate-Ireland will meet the business contacts test upon the completion of the Transaction. However, Seagate-Ireland could fail to satisfy the shareholder test and/or the business contacts test at some time in the future and, as a result, qualify for status as a foreign private issuer. If that occurs, Seagate-Ireland would be exempt from certain requirements applicable to U.S. public companies, including:

•

the rules requiring the filing of Quarterly Reports on Form 10-Q and Current Reports on Form 8-K with the SEC;



•

the SEC's rules regulating proxy solicitations;



•

the provisions of Regulation FD;



•

the filing of reports of beneficial ownership under Section 16 of the Exchange Act (although beneficial ownership reports may be required under Section 13 of the Exchange Act); and



•

"short-swing" trading liability imposed on insiders who purchase and sell securities within a six-month period.

        In addition, Seagate-Ireland would then be allowed to:

•

file annual reports within six months after the end of a fiscal year, and, pursuant to changes to the rules and regulations of the SEC, within four months after the end of a fiscal year beginning with fiscal years ending on or after December 15, 2011;



•

include more limited compensation disclosure in its filings with the SEC;



•

apply accounting principles other than U.S. GAAP to its financial statements, although reconciliation to U.S. GAAP would be required if International Financial Reporting Standards are not used; and



•

choose which reporting currency to use in presenting its financial statements.

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Required Vote; Board Recommendation

        The Special Scheme Meeting will be conducted in accordance with the directions of the Cayman Court. The presence in person or by proxy of the at least two registered holders of common shares is required to constitute a quorum. Assuming the presence of a quorum at the meeting, the Scheme of Arrangement must be approved by a majority in number of the holders of the Seagate-Cayman common shares present and voting on the proposal, whether in person or by proxy, representing 75% or more in value of the Seagate-Cayman common shares present and voting on the proposal, whether in person or by proxy. Please see "The Special Scheme Meeting and the Extraordinary General Meeting—Record Date; Voting Rights; Vote Required for Approval."

THE BOARD OF DIRECTORS HAS APPROVED THE SCHEME OF
ARRANGEMENT AND RECOMMENDS
VOTING "FOR" APPROVAL OF THE SCHEME OF ARRANGEMENT.

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PROPOSAL NUMBER TWO: THE CAPITAL REDUCTION

        The Transaction involves the cancellation of the common shares of Seagate-Cayman, in exchange for which holders of common shares so cancelled will receive, on a one-for-one basis, common shares in Seagate-Ireland. Immediately after that cancellation, Seagate-Cayman will issue new common shares to Seagate-Ireland, becoming a wholly owed subsidiary of Seagate-Ireland. The Scheme of Arrangement Proposal is conditioned upon the approval of this Proposal Number Two. The Transaction can not occur without the approval of both Proposal Number One and Proposal Number Two.

        We are proposing this structure, whereby shares are cancelled and reissued, as opposed to a structure whereby the common shares of Seagate-Cayman are transferred to Seagate-Ireland, because it is generally more tax effective for our shareholders.

        Under Cayman Islands law and the Seagate-Cayman articles of association, Seagate-Cayman may reduce its share capital by cancelling its outstanding shares if such a proposal is approved by a special resolution of Seagate-Cayman's common shareholders, at which at least ²/3 of those attending the meeting in person or by proxy must vote in favor of the proposal. As a result, in order to effect the Scheme of Arrangement, Seagate-Cayman's common shareholders are being asked to approve the Capital Reduction Proposal at the Extraordinary General Meeting.

        In addition, the Cayman Court must approve any share capital reduction. Assuming that we obtain the necessary approval for the Capital Reduction Proposal from the Seagate-Cayman common shareholders, we intend to petition the Cayman Court for an order confirming the capital reduction. We intend to seek directions from the Cayman Court in connection with that petition and Seagate-Cayman's proposed capital reduction on or about [*], 2010 (the "Share Capital Reduction Directions Hearing").

        At the Share Capital Reduction Directions Hearing, we will ask the Cayman Court to make orders (a) dispensing with the need to settle a list of the Seagate-Cayman's creditors (essentially, on the basis that Seagate-Cayman is clearly solvent and in any event the Capital Reduction Proposal has no material effect on Seagate-Cayman's net asset position); and (b) for the advertising of the Capital Reduction Proposal in appropriate newspapers and/or other media.

        The final order of the Cayman Court confirming the Capital Reduction Proposal will then be sought at the Sanction Hearing, concurrently with seeking the Cayman Court's sanction for the Scheme of Arrangement. At that hearing, in connection with the Capital Reduction Proposal, the Court must be satisfied that (a) the shareholders were treated equitably; (b) the reduction proposals were properly explained; (c) the creditors were safeguarded; and (d) the capital reduction was for a discernable purpose. Provided the necessary resolution is passed at the Extraordinary General Meeting, we anticipate that we will be able to satisfy the Cayman Court of these matters, and we anticipate that the Cayman Court will confirm the capital reduction.

        The Capital Reduction Proposal is ancillary and conditional to the Scheme of Arrangement described in Proposal Number One. The Transaction cannot proceed if the Capital Reduction Proposal is not approved. If approved, the Capital Reduction Proposal will take effect at the Transaction Time, and will not proceed unless the Transaction proceeds.

Required Vote

        The Capital Reduction Proposal must be approved by the affirmative vote of the not less than ²/3 of all common shares present and voting, in person or by proxy at the Extraordinary General Meeting.

THE BOARD OF DIRECTORS RECOMMENDS
VOTING "FOR" THE CAPITAL REDUCTION PROPOSAL

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PROPOSAL NUMBER THREE: CREATION OF DISTRIBUTABLE RESERVES

        Under Irish law, dividends and distributions may only be made from distributable reserves in its unconsolidated balance sheet prepared in accordance with the Irish Companies Acts. Distributable reserves generally means the accumulated realized profits of Seagate-Ireland less accumulated realized losses of Seagate-Ireland and includes reserves created by way of capital reduction. In addition, no distribution or dividend may be made unless the net assets of Seagate-Ireland are equal to, or in excess of, the aggregate of Seagate-Ireland's called up share capital plus undistributable reserves and the distribution does not reduce Seagate-Ireland's net assets below such aggregate. Undistributable reserves include the share premium account, the capital redemption reserve fund and the amount by which Seagate-Ireland's accumulated unrealized profits, so far as not previously utilized by any capitalization, exceed Seagate-Ireland's accumulated unrealized losses, so far as not previously written off in a reduction or reorganization of capital. Please see "Description of Seagate Technology plc Share Capital—Dividends" and "—Share Repurchases, Redemptions and Conversions."

        Immediately following implementation of the Transaction, the unconsolidated balance sheet of Seagate-Ireland will not contain any distributable reserves, and "shareholders' equity" in such balance sheet will be comprised entirely of "share capital" (equal to the aggregate par value of the Seagate-Ireland shares issued in the Transaction) and "share premium" resulting from the issuance of Seagate-Ireland shares in the Transaction (equal to (a) the aggregate market value of the Seagate-Cayman common shares as of the close of trading on the NASDAQ on the day the Scheme of Arrangement becomes effective, less (b) the share capital). The current shareholders of Seagate-Ireland (which are Seagate-Cayman and its nominees) have passed a resolution that would create distributable reserves following the Transaction by converting the share premium of Seagate-Ireland as of the Transaction Time to distributable reserves. Based upon the closing sale price of Seagate-Cayman's common shares on the NASDAQ on [      ], if the effectiveness of the Scheme of Arrangement were to have occurred after the close of trading on that date, distributable reserves of Seagate-Ireland created in this manner would have been approximately $[            ].

        Seagate-Cayman has not paid a dividend since February 20, 2009. Since the closing of our initial public offering in December 2002, Seagate-Cayman has paid dividends totaling approximately $952 million in the aggregate. The following are dividends paid in the last two fiscal years:

However, on April 13, 2009, Seagate-Cayman announced that it had adopted a policy of no longer paying a quarterly dividend to its common shareholders to enhance liquidity. We do not expect to resume paying dividends for the foreseeable future.

        On January 27, 2010, the board of directors of Seagate-Cayman authorized an Anti-Dilution Share Repurchase Program. The share repurchase program authorizes Seagate-Cayman to repurchase shares of its common shares to offset increases in diluted shares, such as those caused by employee stock plans and convertible debt, used in the determination of diluted net income per share. For the three months ended January 1, 2010, Seagate-Cayman's total shares used in the determination of diluted net income per share was approximately 520 million shares. The timing and number of shares to be repurchased by Seagate-Cayman will be dependent on general business and market conditions, cash

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flows generated by future operations, the price of Seagate-Cayman's common shares, cash requirements for other investing and financing activities, and maintaining compliance with Seagate-Cayman's debt covenants. The authority for the Anti-dilution Share Repurchase Program will continue until terminated by the board of directors of Seagate-Cayman.

        If the Scheme of Arrangement is approved, the common shareholders of Seagate-Cayman also will be asked at the Extraordinary General Meeting to approve the reduction of the share premium of Seagate-Ireland to allow the creation of distributable reserves of Seagate-Ireland that was previously approved by Seagate-Cayman and the other current shareholders of Seagate-Ireland. If the common shareholders of Seagate-Cayman approve the creation of distributable reserves and the Transaction is completed, we will seek to obtain the approval of the Irish High Court, which is required for the creation of distributable reserves to be effective, as soon as practicable following implementation of the Transaction. The approval of the Irish High Court is expected to be obtained within six weeks of the consummation of the Transaction.

        The approval of the distributable reserves proposal is not a condition to the consummation of the Transaction. Accordingly, if the common shareholders of Seagate-Cayman approve the Scheme of Arrangement but do not approve the Distributable Reserves Proposal, and the Transaction is consummated, Seagate-Ireland may not have sufficient distributable reserves to pay dividends or to repurchase or redeem shares following the Transaction, including under the current share repurchase plans of Seagate-Cayman until such time as Seagate-Ireland has created distributable reserves through the generation of future profits from its operations. In addition, although we are not aware of any reason why the Irish High Court would not approve the creation of distributable reserves, there is no guarantee that such approval will be forthcoming. Even if the Irish High Court does approve the creation of distributable reserves, it may take substantially longer than we anticipate. Please see "Risk Factors."

Required Vote

        The affirmative vote of the holders of our common shares representing at least a majority of our common shares present and voting on the proposal, whether in person or by proxy at the Extraordinary General Meeting.

THE BOARD OF DIRECTORS RECOMMENDS
VOTING "FOR" THE DISTRIBUTABLE RESERVES PROPOSAL

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MATERIAL TAX CONSIDERATIONS RELATING TO THE TRANSACTION

        The discussion under the caption "—U.S. Federal Income Tax Considerations" addresses certain material U.S. federal income tax consequences to (1) Seagate-Cayman and Seagate-Ireland of the Transaction, and (2) U.S. holders and non-U.S. holders (each as defined below) of exchanging Seagate-Cayman shares for Seagate-Ireland shares in the Transaction and owning and disposing of Seagate-Ireland shares received in the Transaction.

        The discussion under the caption "—Irish Tax Considerations" addresses certain material Irish tax consequences to shareholders of the Transaction and of ownership and disposition of the Seagate-Ireland shares.

        The discussion under the caption "—Cayman Islands Tax Considerations" addresses the Cayman Islands income tax consequences of the Transaction.

        The below discussion is not a substitute for an individual analysis of the tax consequences of the Transaction, post-Transaction ownership and disposition of Seagate-Ireland shares or post-Transaction operations of Seagate-Ireland. You should consult your own tax advisors regarding the particular U.S. (federal, state and local), Irish, Cayman Islands and other non-U.S. tax consequences of these matters in light of your particular situation.

U.S. Federal Income Tax Considerations

Scope of Discussion

        This discussion generally does not address any aspects of U.S. taxation other than U.S. federal income taxation, is not a complete analysis or listing of all potential tax consequences of the Transaction or of holding and disposing of Seagate-Ireland shares, and does not address all tax considerations that may be relevant to Seagate-Cayman shareholders. In particular, the below discussion addresses tax consequences to holders that hold their Seagate-Cayman shares, and whom will hold their Seagate-Ireland shares, solely as capital assets, which generally means property held for investment. The below discussion does not address any tax consequences to Seagate-Cayman or Seagate-Ireland shareholders, as applicable, who, for U.S. federal tax purposes, are subject to special rules, such as:

•

banks, financial institutions or insurance companies;



•

tax-exempt entities;



•

persons who hold shares as part of a straddle, hedge, integrated transaction or conversion transaction;



•

persons who have been, but are no longer, citizens or residents of the U.S.;



•

persons holding shares through a partnership or other fiscally transparent person;



•

dealers or traders in securities, commodities or currencies;



•

grantor trusts;



•

persons subject to the alternative minimum tax;



•

U.S. persons whose "functional currency" is not the U.S. dollar;



•

regulated investment companies and real estate investment trusts;



•

persons whose shares constitute "Section 306 stock" (as defined in the Code);



•

persons who received the Seagate-Cayman shares through exercise of employee share options or otherwise as compensation or through a tax qualified retirement plan;

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•

persons who, at any time within the five-year period ending on the date of the Transaction, have owned (directly, indirectly or through attribution) 10% or more of the total combined voting power of all classes of shares entitled to vote of Seagate-Cayman; or



•

persons who, immediately after the Transaction, own (directly, indirectly or through attribution) 10% or more of the total combined voting power of all classes of shares entitled to vote of Seagate-Ireland.

        This discussion is based on the U.S. Internal Revenue Code of 1986, as amended, which we refer to as the "Code," the Treasury regulations promulgated thereunder, which we refer to as the "Treasury Regulations," judicial and administrative interpretations thereof and the Convention Between the Government of the United States of America and the Government of Ireland for the Avoidance of Double Taxation and the Prevention of Fiscal Evasion with respect to Taxes on Income and Capital Gains (the "Ireland-U.S. Tax Treaty"), in each case as in effect on the date of this proxy statement. All of the foregoing are subject to change, which change could apply with retroactive effect and could affect the tax consequences described in this proxy. The discussion assumes, as is the case under current law, that Seagate-Cayman is treated as a foreign person for U.S. federal tax purposes and will be so treated as of and after the effective time of the Transaction. Neither Seagate-Cayman nor Seagate-Ireland will request a ruling from the U.S. Internal Revenue Service, which we refer to as the "IRS," as to the U.S. federal tax consequences of the Transaction, post-Transaction ownership and disposition of Seagate-Ireland shares or any other matter. There can be no assurance that the IRS will not challenge any of the U.S. federal tax consequences described below.

        For purposes of this discussion, a "U.S. holder" is a beneficial owner of Seagate-Cayman shares or, after the completion of the Transaction, Seagate-Ireland shares, that for U.S. federal income tax purposes is:

•

an individual citizen or resident alien of the U.S.;



•

a corporation or other entity taxable as a corporation created or organized in or under the laws of the U.S. or any state thereof or the District of Columbia;



•

an estate the income of which is subject to U.S. federal income taxation regardless of its source; or



•

a trust, if such trust validly has elected to be treated as a U.S. person for U.S. federal income tax purposes or if (1) a U.S. court can exercise primary supervision over its administration and (2) one or more U.S. persons have the authority to control all of the substantial decisions of the trust.

        A "non-U.S. holder" is a beneficial owner of Seagate-Cayman shares or, after the completion of the Transaction, Seagate-Ireland shares, other than a U.S. holder or an entity or arrangement treated as a partnership for U.S. federal income tax purposes, which we refer to as a "Partnership." If a Partnership is a beneficial owner of Seagate-Cayman shares or Seagate-Ireland shares, the tax treatment of a partner in that Partnership will generally depend on the status of the partner and the activities of the Partnership. Holders of Seagate-Cayman shares or Seagate-Ireland shares that are Partnerships and partners in such Partnerships should consult their tax advisor regarding the U.S. federal income tax consequences to them of the Transaction and the ownership and disposition of Seagate-Ireland shares. For purposes of this tax discussion, "holder" or "shareholder" means either a U.S. holder or a non-U.S. holder or both, as the context may require.

Material U.S. Tax Consequences to Seagate-Cayman and Seagate-Ireland

        Neither Seagate-Cayman nor Seagate-Ireland should be subject to U.S. federal income tax as a result of the Transaction. The Transaction should qualify as a Section 368(a)(1)(F) reorganization. The

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discussion below describes the general consequences to U.S. holders and non-U.S. holders of the Transaction qualifying as a Section 368(a)(1)(F) reorganization.

Material U.S. Tax Consequences to U.S. Holders

        The Transaction.    A U.S. holder who receives Seagate-Ireland shares in the Transaction should not recognize any gain or loss solely as a result of the Transaction. Consequently, the tax basis of the Seagate-Ireland shares received in exchange for Seagate-Cayman shares will be equal to the basis of the Seagate-Cayman shares exchanged. U.S. holders whose tax basis in their Seagate-Cayman shares exceeds the fair market value of such shares at the time of the Transaction will be able to carry over the tax basis (and thus the inherent "loss") of their Seagate-Cayman shares to their Seagate-Ireland shares. Thus, subject to any subsequent changes in the fair market value of the Seagate-Ireland shares, any inherent loss will be preserved. The holding period for the Seagate-Ireland shares received in the Transaction will include the holding period for the Seagate-Cayman shares surrendered in the Transaction. Under applicable Treasury Regulations, a U.S. holder should not be required to file a "gain recognition agreement," which we refer to as a "GRA," with the IRS solely as a result of the Transaction. U.S. holders who hold their Seagate-Cayman shares with differing tax bases or holding periods are urged to consult their tax advisor with regard to identifying the tax bases and holding periods of the particular Seagate-Ireland shares received in the Transaction.

        Receiving Distributions on Seagate-Ireland Shares.    Subject to the discussion below under "—Passive Foreign Investment Company Provisions," U.S. holders will be required to include in gross income the gross amount of any distribution received on the Seagate-Ireland shares to the extent that the distribution is paid out of Seagate-Ireland's current or accumulated earnings and profits as determined for U.S. federal income tax purposes, which we refer to as a dividend. With respect to non-corporate U.S. holders, certain dividends received from a qualified foreign corporation will be subject to U.S. federal income tax at a maximum rate of 15%. This reduced rate is scheduled to expire effective for taxable years beginning after December 31, 2010. As long as the Seagate-Ireland shares are listed on the NASDAQ (or certain other stock exchanges) and/or Seagate-Ireland qualifies for benefits under the Ireland-U.S. Tax Treaty, and Seagate-Ireland has not been and is not considered a Passive Foreign Investment Company during the relevant period, Seagate-Ireland will be treated as a qualified foreign corporation for this purpose. As a result of these rules, Seagate believes that it will be a qualified person. This reduced rate will not be available in all situations, and U.S. holders should consult their own tax advisor regarding the application of the relevant rules to their particular circumstances.

        Dividends from Seagate-Ireland, like dividends from Seagate-Cayman, will not be eligible for the dividends-received deduction under the Code, which is generally allowed to U.S. corporate shareholders on dividends received from certain domestic and foreign corporations.

        Like distributions from Seagate-Cayman, distributions from Seagate-Ireland in excess of its current and accumulated earnings and profits will be applied first to reduce the U.S. holder's tax basis in its Seagate-Ireland shares, and thereafter will constitute gain from the sale or exchange of such shares. In the case of a non-corporate U.S. holder, the maximum U.S. federal income tax rate applicable to such "gain" is 15% under current law if the holder's holding period for such Seagate-Ireland shares exceeds twelve months. This reduced rate is scheduled to expire effective for taxable years beginning after December 31, 2010. Special rules not here described may apply to U.S. holders who do not have a uniform tax basis and holding period in all of their Seagate-Ireland shares, and any such U.S. holders are urged to consult their own tax advisor with regard to such rules.

        Dispositions of Seagate-Ireland Shares.    Subject to the discussion below under "—Repurchase of Shares by Seagate" and "—Passive Foreign Investment Company Provisions," U.S. holders of Seagate-Ireland shares, like current U.S. holders of Seagate-Cayman shares, generally should recognize capital gain or loss for U.S. federal income tax purposes on the sale, exchange or other taxable disposition of

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Seagate-Ireland shares in an amount equal to the difference between the amount realized from such sale, exchange or other taxable disposition and the U.S. holders' tax basis in such shares. In the case of a non-corporate U.S. holder, the maximum U.S. federal income tax rate applicable to such gain is 15% under current law if the holder's holding period for such Seagate-Ireland shares exceeds twelve months. This reduced rate is scheduled to expire effective for taxable years beginning after December 31, 2010. The deductibility of capital losses is subject to limitations.

        Repurchase of Shares by Seagate.    Like a repurchase of common shares by Seagate-Cayman, a repurchase of ordinary shares by Seagate generally will be treated as a dividend to the extent of Seagate-Ireland's current and accumulated earnings and profits unless it satisfies one of the alternative tests under Section 302(b) of the Code to be treated as a sale or exchange, subject to the potential application of the PFIC rules as discussed below under "—Passive Foreign Investment Company Provisions". The tests for determining whether a repurchase of shares will qualify as a sale or exchange under Section 302(b) of the Code include whether a repurchase (i) is "substantially disproportionate," (ii) constitutes a "complete termination of the holder's stock interest" in Seagate-Ireland or (iii) is "not essentially equivalent to a dividend," each within the meaning of Section 302(b) of the Code. In determining whether any of the tests under Section 302(b) of the Code are met, including the tests mentioned in the preceding sentence, shares considered to be owned by the U.S. holder under certain constructive ownership rules, as well as shares actually owned, generally must be taken into account. Because the determination of whether any of the alternative tests of Section 302(b) of the Code are satisfied with respect to a particular U.S. holder will depend on the particular facts and circumstances at the time the determination is made, U.S. holders are advised to consult their own tax advisors to determine their tax treatment in light of their own particular circumstances.

        Treatment of Certain Irish Taxes.    For U.S. tax purposes, any Irish stamp duty or Irish capital acquisitions tax imposed on a U.S. holder, as described below under "—Irish Tax Considerations—Stamp Duty" and "—Irish Tax Considerations—Capital Acquisitions Tax," will not be creditable against U.S. federal income taxes. U.S. holders should consult their tax advisors regarding the treatment of these Irish taxes.

        Passive Foreign Investment Company Provisions.    The treatment of U.S. holders of Seagate-Ireland shares in some cases could be materially different from that described above if, at any relevant time, Seagate-Cayman or Seagate-Ireland were a passive foreign investment company, which we refer to as a "PFIC."

        For U.S. tax purposes, a foreign corporation will generally be classified as a PFIC for any taxable year if either (1) 75% or more of its gross income is "passive income" (as defined for U.S. federal income tax purposes) or (2) the average percentage of assets held by such corporation which produce passive income or which are held for the production of passive income is at least 50%. For purposes of applying the tests in the preceding sentence, a look-through rule applies and the foreign corporation is deemed to own its proportionate share of the assets, and to receive directly the proportionate share of the income, of any other corporation of which the foreign corporation owns, directly or indirectly, at least 25% by value of the stock.

        Seagate believes that it is not a PFIC, and has not been a PFIC in any prior taxable year. Seagate further believes that Seagate-Ireland will not become a PFIC as a result of the Transaction or as a result of its business operations and asset holdings following the Transaction. The tests for determining PFIC status are applied annually, and it is difficult to accurately predict future income and assets relevant to this determination. Accordingly, no assurance can be given that the IRS would not challenge this position or that a court would not sustain such challenge.

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        If Seagate-Ireland should determine in the future that it is a PFIC, it will endeavor to so notify U.S. holders of Seagate-Ireland shares, although there can be no assurance that it will be able to do so in a timely and complete manner.

        U.S. holders of Seagate-Ireland shares should consult their own tax advisor about the PFIC rules, including the availability of certain elections.

Material U.S. Tax Consequences to Non-U.S. Holders

        The Transaction.    A non-U.S. holder generally should not be subject to U.S. federal income or withholding tax on gain realized, if any, on the receipt of Seagate-Ireland shares in exchange for their Seagate-Cayman shares.

        Consequences of Owning Seagate-Ireland Shares.    A non-U.S. holder generally will not be subject to U.S. federal income or withholding tax on dividends from Seagate-Ireland unless: (1) the dividends are effectively connected with the holder's conduct of a trade or business in the U.S. (or, if a tax treaty applies, the dividends are attributable to a permanent establishment or fixed place of business maintained by the non-U.S. holder in the U.S.); or (2) such non-U.S. holder is subject to backup withholding.

        Consequences of Disposing of Seagate-Ireland Shares.    A non-U.S. holder generally will not be subject to U.S. federal income or withholding tax on any gain recognized on the sale, exchange or other disposition of Seagate-Ireland shares unless: (1) such gain is effectively connected with the conduct by the non-U.S. holder of a trade or business within the U.S. (or, if a tax treaty applies, is attributable to a permanent establishment or fixed place of business maintained by the non-U.S. holder in the U.S.); (2) in the case of certain capital gains recognized by a non-U.S. holder that is an individual, such individual is present in the U.S. for 183 days or more during the taxable year in which the capital gain is recognized and certain other conditions are met; or (3) the non-U.S. holder is subject to backup withholding.

Information Reporting and Backup Withholding

        U.S. holders that own at least five percent (of total voting power or total value) of Seagate-Cayman immediately before the Transaction will be required to file a Section 368(a) statement. Other information reporting could also apply to the Transaction. Shareholders of Seagate-Cayman should consult their own tax advisor about the information reporting requirements that could be applicable to the exchange of Seagate-Cayman shares for Seagate-Ireland shares in the Transaction.

        Dividends on Seagate-Ireland shares paid within the U.S. or through certain U.S.-related intermediaries are subject to information reporting unless the holder is a corporation, other exempt recipient or non-U.S. holder who establishes such foreign status. Dividends subject to information reporting are subject to backup withholding (currently at a rate of 28%) unless the payee furnishes the payor with a taxpayer identification number and satisfies certain certification requirements. Information reporting requirements and backup withholding may also apply to the payment of proceeds from a sale of Seagate-Ireland shares within the U.S. or through certain U.S.-related intermediaries. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against the holder's U.S. federal income tax liability, provided that the holder furnishes certain required information to the IRS.

        If a U.S. holder of Seagate-Ireland shares does not provide us (or our paying agent) with the holder's correct taxpayer identification number or other required information, the holder may be subject to penalties imposed by the IRS.

        In order for a non-U.S. holder to not be subject to backup withholding tax on a subsequent disposition of Seagate-Ireland shares, or dividends paid on those shares, a non-U.S. holder may be

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required to provide a taxpayer identification number, certify the holder's foreign status or otherwise establish an exemption.

        Holders should consult their tax advisor regarding the application of information reporting and backup withholding to their particular situations.

        THE U.S. FEDERAL INCOME TAX CONSIDERATIONS SUMMARIZED ABOVE ARE FOR GENERAL INFORMATION ONLY. EACH SEAGATE-CAYMAN SHAREHOLDER SHOULD CONSULT HIS OR HER TAX ADVISOR AS TO THE PARTICULAR CONSEQUENCES THAT MAY APPLY TO SUCH SHAREHOLDER.

Irish Tax Considerations

Scope of Discussion

        The following is a general summary of the main Irish tax considerations applicable to certain investors who are the beneficial owners of Seagate-Ireland shares. It is based on existing Irish law and practices in effect on the date of this proxy statement and on discussions and correspondence with the Irish Revenue Commissioners. Legislative, administrative or judicial changes may modify the tax consequences described below.

        The statements do not constitute tax advice and are intended only as a general guide. Furthermore, this information applies only to Seagate-Ireland shares held as capital assets and does not apply to all categories of shareholders, such as dealers in securities, trustees, insurance companies, collective investment schemes and shareholders who have, or who are deemed to have, acquired their Seagate-Ireland shares by virtue of an office or employment. This summary is not exhaustive and shareholders should consult their own tax advisors as to the tax consequences in Ireland, or other relevant jurisdictions of the Transaction, including the acquisition, ownership and disposition of the Seagate-Ireland shares.

Irish Tax on Chargeable Gains

        The receipt by Seagate-Cayman common shareholders of Seagate-Ireland shares as consideration for the cancellation of their Seagate-Cayman shares in the Transaction should not give rise to a liability to Irish tax on chargeable gains (currently at the rate of 25%) for persons that are not resident or ordinarily resident in Ireland for Irish tax purposes and do not hold such shares in connection with a trade carried on by such holder in Ireland through a branch or agency.

        The receipt by Seagate-Cayman common shareholders who are resident or ordinarily resident for tax purposes in Ireland, or who hold their shares in connection with a trade carried on by such holder in Ireland through a branch or agency, or Seagate-Ireland shares as consideration for the cancellation of their Seagate-Cayman common shares as per the Transaction, should be treated as falling within the relief for a reorganization for the purposes of taxation of chargeable gains. Accordingly, the Seagate-Ireland shares issued to holders of Seagate-Cayman shares in accordance with their entitlements as holders of Seagate-Cayman shares should be treated as the same asset and as acquired at the same time as the Seagate-Cayman shares. Shareholders should consult their own tax advisor if they believe they may be subject to Irish tax.

Withholding Tax on Dividends

        Distributions made by Seagate-Ireland will generally be subject to dividend withholding tax ("DWT") at the standard rate of Irish income tax (currently 20%) unless one of the exemptions described below applies, which we believe should be the case for the majority of our shareholders. DWT (if any) arises in respect of dividends paid by Seagate-Ireland, as it is tax resident in Ireland. For DWT purposes, a dividend includes any distribution made by Seagate-Ireland to its shareholders,

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including cash dividends, non-cash dividends and additional stock or units taken in lieu of a cash dividend. Seagate-Ireland is responsible for withholding DWT at source and forwarding the relevant payment to the Irish Revenue Commissioners.

        Certain shareholders (both individual and corporate) are entitled to an exemption from DWT. In particular, a shareholder who is neither resident nor ordinarily resident in Ireland for Irish tax purposes and who does not hold shares of Seagate-Ireland in connection with a trade carried on by such holder in Ireland through a branch or agency is not subject to DWT on dividends received from Seagate-Ireland if the shareholder is:

•

an individual shareholder resident for tax purposes in a "relevant territory," and the individual is neither resident nor ordinarily resident in Ireland and, in this context "relevant territory" means a Member State of the EU (other than Ireland) and, not being such a Member State, a territory with which Ireland has signed a double taxation convention whether ratified or not and the current list of "relevant territories" is set out at Annex C;



•

a corporate shareholder that is not resident for tax purposes in Ireland and which is ultimately controlled, directly or indirectly, by persons resident in a "relevant territory;"



•

a corporate shareholder resident for tax purposes in a "relevant territory" provided that the corporate shareholder is not under the control, whether directly or indirectly, of a person or persons who is or are resident in Ireland;



•

a corporate shareholder that is not resident for tax purposes in Ireland and whose principal class of shares (or those of its 75% parent) is substantially and regularly traded on a recognized stock exchange either in a "relevant territory" or on such other stock exchange approved by the Irish Minister for Finance; or



•

a corporate shareholder that is not resident for tax purposes in Ireland and is wholly owned, directly or indirectly, by two or more companies where the principal class of shares of each of such companies is substantially and regularly traded on a recognized stock exchange in a "relevant territory" or on such other stock exchange approved by the Irish Minister for Finance,

and provided that, in all cases noted above but subject to the matters described below, the shareholder has provided the appropriate forms to such shareholder's broker for onward transmission to Seagate-Ireland's qualifying intermediary (or other designated agent) (in the case of shares held beneficially), or to Seagate-Ireland or its transfer agent (in the case of shares held directly) prior to payment of the dividend.

        Certain categories of Irish resident shareholders are entitled to an exemption from DWT, including (but not limited to) Irish resident companies, qualifying employee share ownership trusts, collective investment undertakings, charities and pension funds so long as the shareholder has provided its broker, for onward transmission to Seagate-Ireland's qualifying intermediary (or other designated agent) (in the case of shares held beneficially), or Seagate-Ireland or its transfer agent (in the case of shares held directly), with all the necessary documentation prior to payment of the dividend. Except in very limited circumstances, distributions to Irish resident shareholders who are individuals are not exempt from DWT.

Income Tax on Dividends Paid on Seagate-Ireland Shares

        Irish income tax (if any) arises in respect of dividends paid by Seagate-Ireland.

        A shareholder who is neither resident nor ordinarily resident in Ireland and who is entitled to an exemption from DWT, generally has no liability for Irish income tax or the income and health levies on a dividend from Seagate-Ireland unless the shareholder holds Seagate-Ireland shares through a branch or agency in Ireland through which a trade is carried on.

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        A shareholder who is neither resident nor ordinarily resident in Ireland and who is not entitled to an exemption from DWT generally has no additional Irish income tax liability or a liability to the income or health levy unless the shareholder holds Seagate-Ireland shares through a branch or agency in Ireland through which a trade is carried on. The DWT deducted by Seagate-Ireland discharges such liability to Irish income tax provided that the shareholder furnishes the statement of DWT imposed to the Irish Revenue.

        Irish resident or ordinarily resident shareholders or shareholders who hold shares of Seagate-Ireland in connection with a trade carried on by such holder in Ireland through a branch or agency may be subject to Irish tax and/or levies on dividends received from Seagate-Ireland. Such shareholders should consult their own tax advisor.

Capital Acquisitions Tax

        Irish capital acquisitions tax ("CAT") comprises principally of gift tax and inheritance tax. CAT could apply to a gift or inheritance of Seagate-Ireland ordinary shares irrespective of the place of residence, ordinary residence or domicile of the parties. This is because Seagate-Ireland ordinary shares are regarded as property situated in Ireland as the share register of Seagate-Ireland must be held in Ireland. The person who receives the gift or inheritance has primary liability for CAT.

        CAT is levied at a rate of 25% above certain tax-free thresholds. The appropriate tax-free threshold is dependent upon (1) the relationship between the donor and the donee and (2) the aggregation of the values of previous gifts and inheritances received by the donee from persons within the same group threshold. Gifts and inheritances passing between spouses are exempt from CAT.

        Shareholders should consult their own tax advisor as to whether CAT is creditable or deductible in computing any tax liabilities in their country of domicile or residence.

Stamp Duty

        Irish stamp duty (if any) is only payable in respect of the transfer of Seagate-Ireland shares and not Seagate-Cayman shares. Irish stamp duty is currently 1% of the price paid or the market value of the shares acquired, if higher.

        No stamp duty should be payable on the cancellation of the common shares of Seagate-Cayman or the issue of Seagate-Ireland ordinary shares under the Transaction.

        For the majority of transfers of Seagate-Ireland ordinary shares, we do not expect there to be any Irish stamp duty as transfers of book-entry interests in DTC representing Seagate-Ireland shares should not be subject to Irish stamp duty. Accordingly, transfers by shareholders who hold their Seagate-Ireland shares beneficially through brokers, which in turn hold those shares through DTC, should not be subject to Irish stamp duty on transfers to holders who also hold through DTC. Transfers by shareholders who hold their shares other than through DTC, will be subject to Irish stamp duty, which is a legal obligation of the buyer. Accordingly, we recommend that all directly registered shareholders open broker accounts so they can transfer their Seagate-Cayman shares into a broker account to be held through DTC as soon as possible, and in any event prior to the Transaction Time. This will cause their Seagate-Ireland shares to be held through DTC from the Transaction Time. We also recommend that any person who wishes to acquire Seagate-Ireland shares after completion of the Transaction acquires such Seagate-Ireland shares beneficially through a broker account to be held through DTC.

        In relation to any transfer of Seagate-Ireland shares that is subject to Irish stamp duty, Seagate-Ireland's articles of association allow Seagate-Ireland, in its absolute discretion, to create an instrument of transfer and pay (or procure the payment of) any stamp duty payable by a buyer. In the event of any such payment, Seagate-Ireland is (on behalf of itself or its affiliates) entitled to (i) seek reimbursement from the buyer or seller (at its discretion), (ii) set-off the amount of the stamp duty against future

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dividends payable to the buyer or seller (at its discretion), and (iii) claim a lien against the Seagate-Ireland shares on which it has paid stamp duty. Parties to a share transfer may assume that any stamp duty arising in respect of a transaction in Seagate-Ireland shares has been paid unless one or both of such parties is otherwise notified by us.

Cayman Islands Tax Considerations

        The Transaction should not result in any income tax consequences under Cayman Islands law to Seagate-Cayman or Seagate-Ireland or their respective shareholders.

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DESCRIPTION OF SEAGATE TECHNOLOGY PLC SHARE CAPITAL

        The following description of Seagate-Ireland's share capital is a summary. This summary is subject to the Irish Companies Acts and the complete text of Seagate-Ireland's memorandum and articles of association substantially in the form attached as Annex B to this proxy statement. We encourage you to read those laws and documents carefully.

        There are differences between Seagate-Cayman's memorandum and articles of association and Seagate-Ireland's memorandum and articles of association as they will be in effect after the Transaction, especially relating to changes (i) that are required by Irish law (i.e., certain provisions of the Seagate-Cayman articles of association were not replicated in the Seagate-Ireland articles of association because Irish law would not permit such replication, and certain provisions were included in the Seagate-Ireland articles of association although they were not in the Seagate-Cayman articles of association because Irish law requires such provisions to be included in the articles of association of an Irish plc), or (ii) that are necessary in order to preserve the current rights of shareholders and powers of the board of directors of Seagate following the Transaction. See "Comparison of Rights of Shareholders and Powers of the Board of Directors." Except where otherwise indicated, the description below reflects Seagate-Ireland's memorandum and articles of association as those documents will be in effect upon completion of the Transaction.

Capital Structure

        Authorized Share Capital.    The authorized share capital of Seagate-Ireland is €40,000 divided into 40,000 ordinary shares with a nominal value of €1 per share and US$13,500 divided into 1,250,000,000 ordinary shares with a nominal value of US$0.00001 per share and 100,000,000 preferred shares with a nominal value of US$0.00001 per share. The authorized share capital includes 40,000 ordinary shares with a nominal value of €1 per share in order to satisfy statutory requirements for all Irish public limited companies commencing operations.

        Seagate-Ireland may issue shares subject to the maximum prescribed by its authorized share capital contained in its memorandum and articles of association. The authorized share capital may be increased or reduced by way of an ordinary resolution of Seagate-Ireland's shareholders. The shares comprising the authorized share capital of Seagate-Ireland may be divided into shares of such nominal value as the resolution shall prescribe. As a matter of Irish company law, the directors of a company may issue new ordinary or preferred shares without shareholder approval once authorized to do so by the articles of association of the company or by an ordinary resolution adopted by the shareholders at a general meeting. An ordinary resolution requires the approval of over 50% of the votes of a company's shareholders cast at a general meeting. The authority conferred can be granted for a maximum period of five years, at which point it must be renewed by the shareholders of the company by an ordinary resolution. Because of this requirement of Irish law, the articles of association of Seagate-Ireland authorize the board of directors of Seagate-Ireland to issue new ordinary or preferred shares without shareholder approval for a period of five years from the date of adoption of such articles of association, which is expected to be effective in the fourth quarter of fiscal year 2010.

        The rights and restrictions to which the ordinary shares will be subject will be prescribed in Seagate-Ireland's articles of association. Seagate-Ireland's articles of association entitle the board of directors, without shareholder approval, to determine the terms of the preferred shares issued by Seagate-Ireland. The Seagate-Ireland board of directors is authorized, without obtaining any vote or consent of the holders of any class or series of shares, unless expressly provided by the terms of that class or series of shares, to provide from time to time for the issuance of other classes or series of preferred shares and to establish the characteristics of each class or series, including the number of shares, designations, relative voting rights, dividend rights, liquidation and other rights, redemption, repurchase or exchange rights and any other preferences and relative, participating, optional or other rights and limitations not inconsistent with applicable law.

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        Irish law does not recognize fractional shares held of record. Accordingly, Seagate-Ireland's articles of association do not provide for the issuance of fractional shares of Seagate-Ireland, and the official Irish register of Seagate-Ireland will not reflect any fractional shares.

        Issued Share Capital.    Immediately prior to the Transaction, the issued share capital of Seagate-Ireland will be €40,000, comprised of 40,000 ordinary shares, with nominal value of €1 per share (the "Euro Share Capital"). In connection with the consummation of the Transaction, the Euro Share Capital will be acquired by Seagate-Ireland for no consideration and will then be cancelled by Seagate-Ireland. Seagate-Ireland will simultaneously issue a number of ordinary shares with a nominal value of US$0.00001 per share each that is equal to the number of Seagate-Cayman common shares that will be cancelled as part of the Transaction. All shares issued upon completion of the Transaction will be issued as fully-paid up and non-assessable.

Pre-emption Rights, Share Warrants and Share Options

        Under Irish law certain statutory pre-emption rights apply automatically in favor of shareholders where shares are to be issued for cash. However, Seagate-Ireland has opted out of these pre-emption rights in its articles of association as permitted under Irish company law. Because Irish law requires this opt-out to be renewed every five years by a special resolution of the shareholders, Seagate-Ireland's articles of association provide that this opt-out must be so renewed. A special resolution requires the approval of not less than 75% of the votes of Seagate-Ireland's shareholders cast at a general meeting. If the opt-out is not renewed, shares issued for cash must be offered to existing shareholders of Seagate-Ireland pro rata to their existing shareholding before the shares can be issued to any new shareholders. The statutory pre-emption rights do not apply where shares are issued for non-cash consideration (such as in a stock-for-stock acquisition) and do not apply to the issue of non-equity shares (that is, shares that have the right to participate only up to a specified amount in any income or capital distribution).

        The articles of association of Seagate-Ireland provide that, subject to any shareholder approval requirement under any laws, regulations or the rules of any stock exchange to which Seagate-Ireland is subject, the board is authorized, from time to time, in its discretion, to grant such persons, for such periods and upon such terms as the board deems advisable, options to purchase such number of shares of any class or classes or of any series of any class as the board may deem advisable, and to cause warrants or other appropriate instruments evidencing such options to be issued. The Irish Companies Acts provide that directors may issue share warrants or options without shareholder approval once authorized to do so by the articles of association or an ordinary resolution of shareholders. The Seagate-Ireland board may issue shares upon exercise of warrants or options without shareholder approval or authorization (up to the relevant authorized share capital limit). In connection with the Transaction, Seagate-Ireland will assume, on a one-for-one basis, Seagate-Cayman's existing obligations to deliver shares under our equity incentive plans, warrants or other rights pursuant to the terms thereof.

        The Irish Companies Acts prohibit an Irish company from allotting shares for "nil" or no consideration. Accordingly, the nominal value of the shares underlying any restricted share award, restricted share unit, performance shares awards, bonus shares or any other share-based grants must be paid pursuant to the Irish Companies Acts. This nominal value payment will include rights to ordinary shares issued by Seagate-Ireland to employees under the assumed equity incentive plans.

        Seagate-Ireland will be subject to the rules of the NASDAQ and the Code that require shareholder approval of certain equity plan and share issuances.

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Dividends

        Under Irish law, dividends and distributions may only be made from distributable reserves. Distributable reserves generally means the accumulated realized profits of Seagate-Ireland less accumulated realized losses of Seagate-Ireland and includes reserves created by way of capital reduction. In addition, no distribution or dividend may be made unless the net assets of Seagate-Ireland are equal to, or in excess of, the aggregate of Seagate-Ireland's called up share capital plus undistributable reserves and the distribution does not reduce Seagate-Ireland's net assets below such aggregate. Undistributable reserves include the share premium account, the capital redemption reserve fund and the amount by which Seagate-Ireland's accumulated unrealized profits, so far as not previously utilized by any capitalization, exceed Seagate-Ireland's accumulated unrealized losses, so far as not previously written off in a reduction or reorganization of capital.

        The determination as to whether or not Seagate-Ireland has sufficient distributable reserves to fund a dividend must be made by reference to "relevant accounts" of Seagate-Ireland. The "relevant accounts" will be either the last set of unconsolidated annual audited financial statements or other financial statements properly prepared in accordance with the Irish Companies Acts, which give a "true and fair view" of Seagate-Ireland's unconsolidated financial position and accord with accepted accounting practice. The relevant accounts must be filed in the Companies Registration Office (the official public registry for companies in Ireland).

        Although Seagate-Ireland will not have any distributable reserves immediately following the Transaction Time, we are taking steps to create such distributable reserves. Please see "Risk Factors" and "Proposal Number Three: Creation of Distributable Reserves."

        The mechanism as to who declares a dividend and when a dividend shall become payable is governed by the articles of association of Seagate-Ireland. Seagate-Ireland's articles of association authorize the directors to declare such dividends as appear justified from the profits of Seagate-Ireland without the approval of the shareholders at a general meeting. The board of directors may also recommend a dividend to be approved and declared by the shareholders at a general meeting. The board of directors may direct that the payment be made by distribution of assets, shares or cash and no dividend issued may exceed the amount recommended by the directors. The dividends can be declared and paid in the form of cash or non-cash assets and may be paid in U.S. dollars or any other currency.

        The directors of Seagate-Ireland may deduct from any dividend payable to any shareholder all sums of money (if any) payable by such shareholder to Seagate-Ireland in relation to the shares of Seagate-Ireland.

        The directors of Seagate-Ireland are also entitled to issue shares with preferred rights to participate in dividends declared by Seagate-Ireland. The holders of such preferred shares may, depending on their terms, rank senior to the Seagate-Ireland ordinary shares in terms of dividend rights and/or be entitled to claim arrears of a declared dividend out of subsequently declared dividends in priority to ordinary shareholders.

        For information about the Irish tax issues relating to dividend payments, please see "Material Tax Considerations Relating to the Transaction—Irish Tax Considerations."

Share Repurchases, Redemptions and Conversions

Overview

        Seagate-Ireland's articles of association provide that any ordinary share which Seagate-Ireland has agreed to acquire shall be deemed to be a redeemable share. Accordingly, for Irish company law purposes, the repurchase of ordinary shares by Seagate-Ireland will technically be effected as a redemption of those shares as described below under "—Repurchases and Redemptions by Seagate-Ireland." If the articles of association of Seagate-Ireland did not contain such provision,

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repurchases by Seagate-Ireland would be subject to many of the same rules that apply to purchases of Seagate-Ireland shares by subsidiaries described below under "—Purchases by Subsidiaries of Seagate-Ireland," including the shareholder approval requirements described below and the requirement that any on-market purchases be effected on a "recognized stock exchange." Except where otherwise noted, when we refer elsewhere in this proxy statement to repurchasing or buying back ordinary shares of Seagate-Ireland, we are referring to the redemption of ordinary shares by Seagate-Ireland pursuant to such provision of the articles of association or the purchase of ordinary shares of Seagate-Ireland by a subsidiary of Seagate-Ireland, in each case in accordance with the Seagate-Ireland articles of association and Irish company law as described below.

Repurchases and Redemptions by Seagate-Ireland

        Under Irish law, a company can issue redeemable shares and redeem them out of distributable reserves (which are described above under "—Dividends") or the proceeds of a new issue of shares for that purpose. Although Seagate-Ireland will not have any distributable reserves immediately following the Transaction Time, we are taking steps to create such distributable reserves. Please see "Risk Factors" and "Proposal Number Three: Creation of Distributable Reserves." The issue of redeemable shares may only be made by Seagate-Ireland where the nominal value of the issued share capital that is not redeemable is not less than 10% of the nominal value of the total issued share capital of Seagate-Ireland. All redeemable shares must also be fully-paid and the terms of redemption of the shares must provide for payment on redemption. Redeemable shares may, upon redemption, be cancelled or held in treasury. Based on the provision of Seagate-Ireland's articles described above, shareholder approval will not be required to redeem Seagate-Ireland shares.

        Seagate-Ireland may also be given an additional general authority to purchase its own shares on-market which would take effect on the same terms and be subject to the same conditions as applicable to purchases by Seagate-Ireland's subsidiaries as described below.

        The board of directors of Seagate-Ireland will also be entitled to issue preferred shares which may be redeemed at the option of either Seagate-Ireland or the shareholder, depending on the terms of such preferred shares. Please see above under "—Capital Structure—Authorized Share Capital" for additional information on preferred shares.

        Repurchased and redeemed shares may be cancelled or held as treasury shares. The nominal value of treasury shares held by Seagate-Ireland at any time must not exceed 10% of the nominal value of the issued share capital of Seagate-Ireland. Seagate-Ireland cannot exercise any voting rights in respect of any shares held as treasury shares. Treasury shares may be cancelled by Seagate-Ireland or re-issued subject to certain conditions.

Purchases by Subsidiaries of Seagate-Ireland

        Under Irish law, it may be permissible for an Irish or non-Irish subsidiary to purchase shares of Seagate-Ireland either on-market or off-market. A general authority of the shareholders of Seagate-Ireland (by way of ordinary resolution) is required to allow a subsidiary of Seagate-Ireland to make on-market purchases of Seagate-Ireland shares. However, as long as this general authority has been granted, no specific shareholder authority for a particular on-market purchase by a subsidiary of Seagate-Ireland shares is required. Prior to the Transaction Time, we expect Seagate-Cayman together with the nominee shareholders of Seagate-Ireland to authorize the purchase of Seagate-Ireland shares by subsidiaries of Seagate-Ireland, such that Seagate-Ireland's subsidiaries will be authorized to purchase shares in an aggregate amount approximately equal to the then remaining authorization under the existing Seagate-Cayman share repurchase program. This authority will expire no later than 18 months after the date on which it takes effect.

        In order for a subsidiary of Seagate-Ireland to make an on-market purchase of Seagate-Ireland's shares, such shares must be purchased on a "recognized stock exchange." NASDAQ, on which the

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shares of Seagate-Ireland will be listed following the Transaction, is not currently specified as a recognized stock exchange for this purpose by Irish company law. We expect that the Irish authorities will take appropriate steps in the near future to add the NASDAQ to the list of recognized stock exchanges. For an off-market purchase by a subsidiary of Seagate-Ireland, the proposed purchase contract must be authorized by special resolution of the shareholders of Seagate-Ireland before the contract is entered into. The person whose shares are to be bought back cannot vote in favor of the special resolution and, for at least 21 days prior to the special resolution, the purchase contract must be on display or must be available for inspection by shareholders at the registered office of Seagate-Ireland.

        The number of shares held by the subsidiaries of Seagate-Ireland at any time will count as treasury shares and will be included in any calculation of the permitted treasury share threshold of 10% of the nominal value of the issued share capital of Seagate-Ireland. While a subsidiary holds shares of Seagate-Ireland, it cannot exercise any voting rights in respect of those shares. The acquisition of the shares of Seagate-Ireland by a subsidiary must be funded out of distributable reserves of the subsidiary.

Existing Share Repurchase Program

        On January 27, 2010, the board of directors of Seagate-Cayman authorized an Anti-Dilution Share Repurchase Program. The share repurchase program authorizes Seagate-Cayman to repurchase shares of its common shares to offset increases in diluted shares, such as those caused by employee stock plans and convertible debt, used in the determination of diluted net income per share. For the three months ended January 1, 2010, Seagate-Cayman's total shares used in the determination of diluted net income per share was approximately 520 million shares. The timing and number of shares to be repurchased by Seagate-Cayman will be dependent on general business and market conditions, cash flows generated by future operations, the price of Seagate-Cayman's common shares, cash requirements for other investing and financing activities, and maintaining compliance with Seagate-Cayman's debt covenants. The authority for the Anti-dilution Share Repurchase Program will continue until terminated by the board of directors of Seagate-Cayman.

        Prior to the consummation of the Transaction, we expect (i) the board of directors of Seagate-Ireland to authorize the repurchase of Seagate-Ireland shares by Seagate-Ireland and its subsidiaries and (ii) Seagate-Cayman and the nominee shareholders of Seagate-Ireland to authorize the purchase of Seagate-Ireland shares by subsidiaries of Seagate-Ireland, such that Seagate-Ireland and its subsidiaries will be authorized to purchase shares in an aggregate amount approximately equal to the then remaining authorization under the existing Seagate-Cayman share repurchase program.

        As noted above, because repurchases of Seagate-Ireland shares by Seagate-Ireland can technically be effected as a redemption of those shares pursuant to the articles of association, such repurchases may be made whether or not the NASDAQ is a "recognized stock exchange" and shareholder approval for such repurchases will not be required.

        However, because purchases of Seagate-Ireland shares by subsidiaries of Seagate-Ireland may be made only on a "recognized stock exchange" and only if the required shareholder approval has been obtained, we expect that the shareholder authorization for purchases by subsidiaries of Seagate-Ireland described above will be effective as of the later of (i) the Transaction Time and (ii) the date on which the NASDAQ becomes a recognized stock exchange for this purpose. This authorization will expire no later than 18 months after the date on which it takes effect and we expect that we would seek shareholder approval to renew this authorization at future annual general meetings.

Bonus Shares

        Under Seagate-Ireland's articles of association, upon the recommendation of the directors, the shareholders may by ordinary resolution authorize the directors to capitalize any amount for the time being standing to the credit of any of Seagate-Ireland's reserves (including any capital redemption

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reserve fund or share premium account) or to the credit of profit and loss account for issuance and distribution to shareholders as fully-paid up bonus shares on the same basis of entitlement as would apply in respect of a dividend distribution. An "ordinary resolution" of Seagate-Ireland requires approval by more than 50% of the votes cast at a meeting of shareholders by shareholders entitled to vote at the meeting.

Lien on Shares, Calls on Shares and Forfeiture of Shares

        Seagate-Ireland's articles of association provide that Seagate-Ireland will have a first and paramount lien on every share (not being a fully paid up share) for all moneys payable at a fixed time or called in respect of that share. Subject to the terms of their allotment the directors can also make calls upon the shareholders in respect of any moneys unpaid on their shares and if such payment is not forthcoming the shares in question may be liable to be forfeited. These provisions are standard inclusions in the articles of association of an Irish company limited by shares such as Seagate-Ireland and will only be applicable to shares of Seagate-Ireland that have not been fully paid.

Consolidation and Division; Subdivision

        Under its articles of association, Seagate-Ireland may by ordinary resolution consolidate and divide all or any of its share capital into shares of larger nominal value than its existing shares or subdivide its shares into smaller amounts than is fixed by its articles of association.

Reduction of Share Capital

        Seagate-Ireland may, by ordinary resolution, reduce its authorized share capital in any way. Seagate-Ireland also may, by special resolution and subject to confirmation by the Irish High Court, reduce or cancel its issued share capital in any way. The distributable reserves proposal discussed above in "Proposal Number Three: Creation of Distributable Reserves" involves a reduction of share capital, namely the share premium account of Seagate-Ireland, for purposes of Irish law.

Annual Meetings of Shareholders

        Seagate-Ireland will be required to hold an annual general meeting within 18 months of incorporation and at intervals of no more than 15 months thereafter, provided that an annual general meeting is held in each calendar year following the first annual general meeting and no more than nine months after Seagate-Ireland's fiscal year-end. Seagate-Ireland plans to hold its first annual general meeting in calendar 2010 if the Transaction is consummated. Under Irish law, the first annual general meeting of Seagate-Ireland is permitted to be held outside Ireland. Thereafter, any annual general meeting may be held outside Ireland if a resolution so authorizing has been passed at the preceding annual general meeting. We currently do not intend to hold annual general meetings in Ireland if the Transaction is consummated.

        Notice of an annual general meeting must be given to all shareholders of Seagate-Ireland and to the auditors of Seagate-Ireland. The articles of association of Seagate-Ireland provide for a minimum notice period of 21 days, which is the minimum permitted under Irish law.

        The only matters which must, as a matter of Irish company law, be transacted at an annual general meeting are the presentation of the annual accounts, balance sheet and reports of the directors and auditors, the appointment of new auditors and the fixing of the auditor's remuneration (or delegation of same). If no resolution is made in respect of the reappointment of an existing auditor at an annual general meeting, the existing auditor will be deemed to have continued in office.

        Directors are elected by the affirmative vote of a majority of the votes cast by shareholders at an annual general meeting and serve until the next annual general meeting. Any nominee for director who does not receive a majority of the votes cast is not elected to the board.

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Extraordinary general meetings of Shareholders

        Extraordinary general meetings of Seagate-Ireland may be convened by (i) the board of directors, (ii) on requisition of the shareholders holding not less than 10% of the paid up share capital of Seagate-Ireland carrying voting rights or (iii) on requisition of Seagate-Ireland's auditors. Extraordinary general meetings are generally held for the purposes of approving shareholder resolutions of Seagate-Ireland as may be required from time to time. At any extraordinary general meeting only such business shall be conducted as is set forth in the notice thereof.

        Notice of an extraordinary general meeting must be given to all shareholders of Seagate-Ireland and to the auditors of Seagate-Ireland. Under Irish law, the minimum notice periods are 21 days notice in writing for an extraordinary general meeting to approve a special resolution and 14 days notice in writing for any other extraordinary general meeting. Because of the 21 day and 14 day requirements described in this paragraph, Seagate-Ireland's articles of association include provisions reflecting these requirements of Irish law.

        In the case of an extraordinary general meeting convened by shareholders of Seagate-Ireland, the proposed purpose of the meeting must be set out in the requisition notice. Upon receipt of this requisition notice, the board of directors has 21 days to convene a meeting of Seagate-Ireland's shareholders to vote on the matters set out in the requisition notice. This meeting must be held within two months of the receipt of the requisition notice. If the board of directors does not convene the meeting within such 21 day period, the requisitioning shareholders, or any of them representing more than one half of the total voting rights of all of them, may themselves convene a meeting, which meeting must be held within three months of the receipt of the requisition notice.

        If the board of directors becomes aware that the net assets of Seagate-Ireland are half or less of the amount of Seagate-Ireland's called-up share capital, the directors of Seagate-Ireland must convene an extraordinary general meeting of Seagate-Ireland's shareholders not later than 28 days from the date that they learn of this fact. This meeting must be convened for the purposes of considering whether any, and if so what, measures should be taken to address the situation.

Quorum for General Meetings

        The presence, in person or by proxy, of the holders of not less than a majority of the issued and outstanding shares of the company entitled to vote at such meeting constitutes a quorum for the conduct of business. No business may take place at a general meeting of Seagate-Ireland if a quorum is not present in person or by proxy. The board of directors has no authority to waive quorum requirements stipulated in the articles of association of Seagate-Ireland. Abstentions and broker non-votes will be counted as present for purposes of determining whether there is a quorum in respect of the proposals. A broker "non-vote" occurs when a nominee (such as a broker) holding shares for a beneficial owner abstains from voting on a particular proposal because the nominee does not have discretionary voting power for that proposal and has not received instructions from the beneficial owner on how to vote those shares.

Voting

        Where a poll is demanded at a general meeting, every shareholder shall have one vote for each ordinary share that he or she holds as of the record date for the meeting. Voting rights may be exercised by shareholders registered in Seagate-Ireland's share register as of the record date for the meeting or by a duly appointed proxy of such a registered shareholder, which proxy need not be a shareholder. Where interests in shares are held by a nominee trust company this company may exercise the rights of the beneficial holders on their behalf as their proxy. All proxies must be appointed in the manner prescribed by Seagate-Ireland's articles of association. The articles of association of Seagate-Ireland permit the appointment of proxies by the shareholders to be notified to Seagate-Ireland electronically in such manner as may be approved by the board.

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        Seagate-Ireland's articles of association provide that all resolutions shall be decided by a show of hands unless a poll is demanded by (i) the chairman, (ii) at least 10 shareholders of record, as of the record date for the meeting, or (iii) any shareholder, or shareholders, holding not less than 10% of the total voting rights of Seagate-Ireland as of the record date for the meeting. Each Seagate-Ireland ordinary shareholder of record as of the record date for the meeting has one vote at a general meeting on a show of hands.

        In accordance with the articles of association of Seagate-Ireland, the directors of Seagate-Ireland may from time to time cause Seagate-Ireland to issue preferred shares. These preferred shares may have such voting rights as may be specified in the terms of such preferred shares (e.g., they may carry more votes per share than ordinary shares or may entitle their holders to a class vote on such matters as may be specified in the terms of the preferred shares).

        Treasury shares will not be entitled to be voted at general meetings of shareholders.

        Irish company law requires "special resolutions" of the shareholders at a general meeting to approve certain matters. A special resolution requires the approval of not less than 75% of the votes of Seagate-Ireland's shareholders cast at a general meeting where a quorum is present. This may be contrasted with "ordinary resolutions," which require a simple majority of the votes of Seagate-Ireland's shareholders cast at a general meeting.

        Examples of matters requiring special resolutions include:

•

amending the objects or memorandum of association of Seagate-Ireland;



•

amending the articles of association of Seagate-Ireland;



•

approving the change of name of Seagate-Ireland;



•

authorizing the entering into of a guarantee or provision of security in connection with a loan, quasi-loan or credit transaction to a director or connected person;



•

opting out of pre-emption rights on the issuance of new shares;



•

re-registration of Seagate-Ireland from a plc as a private company;



•

variation of class rights attaching to classes of shares (where the articles of association do not provide otherwise);



•

purchase of own shares off-market;



•

the reduction of share capital;



•

sanctioning a compromise/scheme of arrangement;



•

resolving that Seagate-Ireland be wound up by the Irish courts;



•

resolving in favor of a shareholders' voluntary winding-up;



•

re-designation of shares into different share classes; and



•

setting the re-issue price of treasury shares.

Variation of Rights Attaching to a Class or Series of Shares

        Any variation of class or series rights attaching to the issued shares of Seagate-Ireland is addressed in the articles of association of Seagate-Ireland as well as the Irish Companies Acts and must be in accordance with the articles of association be approved by a special resolution of the class or series affected.

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Inspection of Books and Records

        Under Irish law, shareholders have the right to: (i) receive a copy of the memorandum and articles of association of Seagate-Ireland and any act of the Irish Government which alters the memorandum of association of Seagate-Ireland; (ii) inspect and obtain copies of the minutes of general meetings and resolutions of Seagate-Ireland; (iii) inspect and receive a copy of the register of shareholders, register of directors and secretaries, register of directors' interests and other statutory registers maintained by Seagate-Ireland; (iv) receive copies of balance sheets and directors' and auditors' reports which have previously been sent to shareholders prior to an annual general meeting; and (v) receive balance sheets of a subsidiary company of Seagate-Ireland which have previously been sent to shareholders prior to an annual general meeting for the preceding 10 years. The auditors of Seagate-Ireland will also have the right to inspect all books, records and vouchers of Seagate-Ireland. The auditors' report must be circulated to the shareholders with Seagate-Ireland's financial statements prepared in accordance with Irish law 21 days before the annual general meeting and must be read to the shareholders at Seagate-Ireland's annual general meeting.

Acquisitions

        There are a number of mechanisms for acquiring an Irish plc, including:

        (a)   a court-approved scheme of arrangement under the Irish Companies Acts. A scheme of arrangement with shareholders requires a court order from the Irish High Court and the approval of: (i) 75% of the voting shareholders by value; and (ii) 50% in number of the voting shareholders, at a meeting called to approve the scheme;

        (b)   through a tender offer by a third party for all of the shares of Seagate-Ireland. Where the holders of 80% or more of Seagate-Ireland's shares have accepted an offer for their shares in Seagate-Ireland, the remaining shareholders may be statutorily required to also transfer their shares. If the bidder does not exercise its "squeeze out" right, then the non-accepting shareholders also have a statutory right to require the bidder to acquire their shares on the same terms. If shares of Seagate-Ireland were listed on the Irish Stock Exchange or another regulated stock exchange in the EU, this threshold would be increased to 90%; and

        (c)   it is also possible for Seagate-Ireland to be acquired by way of a merger with an EU-incorporated company under the EU Cross-Border Mergers Directive 2005/56/EC. Such a merger must be approved by a special resolution. If Seagate-Ireland is being merged with another EU company under the EU Cross-Border Mergers Directive 2005/56/EC and the consideration payable to Seagate-Ireland's shareholders is not all in the form of cash, Seagate-Ireland's shareholders may be entitled to require their shares to be acquired at fair value.

        Under Irish law, there is no requirement for a company's shareholders to approve a sale, lease or exchange of all or substantially all of a company's property and assets. However, Seagate-Ireland's articles of association provide that an ordinary resolution of the shareholders is required to approve a sale, lease or exchange of all or substantially all of Seagate-Ireland's property and assets (other than a sale, lease or exchange to or with a subsidiary of Seagate-Ireland).

Appraisal Rights

        Generally, under Irish law, shareholders of an Irish company do not have dissenters or appraisal rights. Under the European Communities (Cross-Border Mergers) Regulations 2008 governing the merger of an Irish company limited by shares such as Seagate-Ireland and a company incorporated in the European Economic Area (the European Economic Area includes all member states of the EU and Norway, Iceland and Liechtenstein), a shareholder (i) who voted against the special resolution approving the merger or (ii) of a company in which 90% of the shares is held by the other company

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the party to the merger of the transferor company has the right to request that the company acquire its shares for cash.

Disclosure of Interests in Shares

        Under the Irish Companies Acts, there is a notification requirement for shareholders who acquire or cease to be interested in five percent of the shares of an Irish plc. A shareholder of Seagate-Ireland must therefore make such a notification to Seagate-Ireland if as a result of a transaction the shareholder will be interested in five percent or more of the shares of Seagate-Ireland; or if as a result of a transaction a shareholder who was interested in more than five percent of the shares of Seagate-Ireland ceases to be so interested. Where a shareholder is interested in more than five percent of the shares of Seagate-Ireland, any alteration of his or her interest that brings his or her total holding through the nearest whole percentage number, whether an increase or a reduction, must be notified to Seagate-Ireland. The relevant percentage figure is calculated by reference to the aggregate nominal value of the shares in which the shareholder is interested as a proportion of the entire nominal value of Seagate-Ireland's share capital. Where the percentage level of the shareholder's interest does not amount to a whole percentage this figure may be rounded down to the next whole number. All such disclosures should be notified to Seagate-Ireland within five business days of the transaction or alteration of the shareholder's interests that gave rise to the requirement to notify. Where a person fails to comply with the notification requirements described above no right or interest of any kind whatsoever in respect of any shares in Seagate-Ireland concerned, held by such person, shall be enforceable by such person, whether directly or indirectly, by action or legal proceeding. However, such person may apply to the court to have the rights attaching to the shares concerned reinstated.

        In addition to the above disclosure requirement, Seagate-Ireland, under the Irish Companies Acts, may by notice in writing require a person whom Seagate-Ireland knows or has reasonable cause to believe to be, or at any time during the three years immediately preceding the date on which such notice is issued, to have been interested in shares comprised in Seagate-Ireland's relevant share capital to: (i) indicate whether or not it is the case; and (ii) where such person holds or has during that time held an interest in the shares of Seagate-Ireland, to give such further information as may be required by Seagate-Ireland including particulars of such person's own past or present interests in shares of Seagate-Ireland. Any information given in response to the notice is required to be given in writing within such reasonable time as may be specified in the notice.

        Where such a notice is served by Seagate-Ireland on a person who is or was interested in shares of Seagate-Ireland and that person fails to give Seagate-Ireland any information required within the reasonable time specified, Seagate-Ireland may apply to court for an order directing that the affected shares be subject to certain restrictions. Under the Irish Companies Acts, the restrictions that may be placed on the shares by the court are as follows:

        (a)   any transfer of those shares, or in the case of unissued shares any transfer of the right to be issued with shares and any issue of shares, shall be void;

        (b)   no voting rights shall be exercisable in respect of those shares;

        (c)   no further shares shall be issued in right of those shares or in pursuance of any offer made to the holder of those shares; and

        (d)   no payment shall be made of any sums due from Seagate-Ireland on those shares, whether in respect of capital or otherwise.

        Where the shares in Seagate-Ireland are subject to these restrictions, the court may order the shares to be sold and may also direct that the shares shall cease to be subject to these restrictions.

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Anti-Takeover Provisions

Irish Takeover Rules and Substantial Acquisition Rules

        A transaction by virtue of which a third party is seeking to acquire 30% or more of the voting rights of Seagate-Ireland will be governed by the Irish Takeover Panel Act 1997 and the Irish Takeover Rules made thereunder and will be regulated by the Irish Takeover Panel. The "General Principles" of the Irish Takeover Rules and certain important aspects of the Irish Takeover Rules are described below.

General Principles

        The Irish Takeover Rules are built on the following General Principles which will apply to any transaction regulated by the Irish Takeover Panel:

•

in the event of an offer, all classes of shareholders of the target company should be afforded equivalent treatment and, if a person acquires control of a company, the other holders of securities must be protected;



•

the holders of securities in the target company must have sufficient time to allow them to make an informed decision regarding the offer;



•

the board of a company must act in the interests of the company as a whole. If the board of the target company advises the holders of securities as regards the offer it must advise on the effects of the implementation of the offer on employment, employment conditions and the locations of the target company's place of business;



•

false markets in the securities of the target company or any other company concerned by the offer must not be created;



•

a bidder can only announce an offer after ensuring that he or she can fulfill in full the consideration offered;



•

a target company may not be hindered longer than is reasonable by an offer for its securities. This is a recognition that an offer will disrupt the day-to-day running of a target company particularly if the offer is hostile and the board of the target company must divert its attention to resist the offer; and



•

a "substantial acquisition" of securities (whether such acquisition is to be effected by one transaction or a series of transactions) will only be allowed to take place at an acceptable speed and shall be subject to adequate and timely disclosure.

Mandatory Bid

        If an acquisition of shares were to increase the aggregate holding of an acquirer and its concert parties to shares carrying 30% or more of the voting rights in Seagate-Ireland, the acquirer and, depending on the circumstances, its concert parties would be required (except with the consent of the Irish Takeover Panel) to make a cash offer for the remaining outstanding shares at a price not less than the highest price paid for the shares by the acquirer or its concert parties during the previous 12 months. This requirement would also be triggered by an acquisition of shares by a person holding (together with its concert parties) shares carrying between 30% and 50% of the voting rights in Seagate-Ireland if the effect of such acquisition were to increase the percentage of the voting rights held by that person (together with its concert parties) by 0.05% within a twelve-month period. A single holder (that is, a holder excluding any parties acting in concert with the holder) holding more than 50% of the voting rights of a company is not subject to this rule.

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Voluntary Bid; Requirements to Make a Cash Offer and Minimum Price Requirements

        A voluntary offer is an offer that is not a mandatory offer. If a bidder or any of its concert parties acquire ordinary shares of Seagate-Ireland within the period of three months prior to the commencement of the offer period, the offer price must be not less than the highest price paid for Seagate-Ireland ordinary shares by the bidder or its concert parties during that period. The Irish Takeover Panel has the power to extend the "look back" period to 12 months if the Irish Takeover Panel, having regard to the General Principles, believes it is appropriate to do so.

        If the bidder or any of its concert parties has acquired ordinary shares of Seagate-Ireland (i) during the period of 12 months prior to the commencement of the offer period which represent more than 10% of the total ordinary shares of Seagate-Ireland or (ii) at any time after the commencement of the offer period, the offer shall be in cash (or accompanied by a full cash alternative) and the price per Seagate-Ireland ordinary share shall be not less than the highest price paid by the bidder or its concert parties during, in the case of (i), the period of 12 months prior to the commencement of the offer period and, in the case of (ii), the offer period. The Irish Takeover Panel may apply this rule to a bidder who, together with its concert parties, has acquired less than 10% of the total ordinary shares of Seagate-Ireland in the 12 month period prior to the commencement of the offer period if the Irish Takeover Panel, having regard to the General Principles, considers it just and proper to do so.

        An offer period will generally commence from the date of the first announcement of the offer or proposed offer.

Substantial Acquisition Rules

        The Irish Takeover Rules also contain rules governing substantial acquisitions of shares which restrict the speed at which a person may increase his or her holding of shares and rights over shares to an aggregate of between 15% and 30% of the voting rights of Seagate-Ireland. Except in certain circumstances, an acquisition or series of acquisitions of shares or rights over shares representing 10% or more of the voting rights of Seagate-Ireland is prohibited, if such acquisition(s), when aggregated with shares or rights already held, would result in the acquirer holding 15% or more but less than 30% of the voting rights of Seagate-Ireland and such acquisitions are made within a period of seven days. These rules also require accelerated disclosure of acquisitions of shares or rights over shares relating to such holdings.

Frustrating Action

        Under the Irish Takeover Rules, the board of directors of Seagate-Ireland is not permitted to take any action which might frustrate an offer for the shares of Seagate-Ireland once the board of directors has received an approach which may lead to an offer or has reason to believe an offer is imminent except as noted below. Potentially frustrating actions such as (i) the issue of shares, options or convertible securities, (ii) material disposals, (iii) entering into contracts other than in the ordinary course of business or (iv) any action, other than seeking alternative offers, which may result in frustration of an offer, are prohibited during the course of an offer or at any time during which the board has reason to believe an offer is imminent. Exceptions to this prohibition are available where:

        (a)   the action is approved by Seagate-Ireland's shareholders at a general meeting; or

        (b)   with the consent of the Irish Takeover Panel where:

          (i)  the Irish Takeover Panel is satisfied the action would not constitute a frustrating action;

         (ii)  the holders of 50% of the voting rights state in writing that they approve the proposed action and would vote in favor of it at a general meeting;

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        (iii)  in accordance with a contract entered into prior to the announcement of the offer; or

        (iv)  the decision to take such action was made before the announcement of the offer and either has been at least partially implemented or is in the ordinary course of business.

        For other provisions that could be considered to have an anti-takeover effect, please see above under "—Authorized Share Capital" (regarding issuance of preferred shares), "—Pre-emption Rights, Share Warrants and Share Options" and "—Disclosure of Interests in Shares," in addition to "—Corporate Governance," "Comparison of Rights of Shareholders and Powers of the Board of Directors—Election of Directors," "—Vacancies on Board of Directors," "—Removal of Directors," "—Amendment of Governing Documents" and "—Director Nominations; Proposals of Shareholders" below.

Corporate Governance

        The articles of association of Seagate-Ireland allocate authority over the day-to-day management of Seagate-Ireland to the board of directors. The board of directors may then delegate the management of Seagate-Ireland to committees (consisting of members of the board or other persons) or executives, but regardless, the directors will remain responsible, as a matter of Irish law, for the proper management of the affairs of Seagate-Ireland. Seagate-Ireland will replicate the existing committees that are currently in place for Seagate-Cayman which include an Audit Committee, a Compensation Committee, a Corporate Governance and Nominating Committee and a Strategic and Financial Transaction Committee. It also is the intention of Seagate-Ireland to adopt Seagate-Cayman's current Corporate Governance Guidelines, Code of Business Conduct and Ethics, Insider Trading Policy and any other policies or guidelines that have been approved by the board of directors of Seagate-Cayman and are in effect as of the Transaction Time.

Legal Name; Formation; Fiscal Year; Registered Office

        The legal and commercial name of Seagate-Ireland is Seagate Technology plc. Seagate-Ireland was incorporated in Ireland, as Hephaestus Public Limited Company on January 22, 2010 with company registration number 480010. Seagate-Ireland's fiscal year ends on the Friday closest to June 30 and Seagate-Ireland's registered address is Arthur Cox Building, Earlsfort Terrace, Dublin 2, Ireland.

Duration; Dissolution; Rights upon Liquidation

        Seagate-Ireland's duration will be unlimited. Seagate-Ireland may be dissolved and wound up at any time by way of a shareholders' voluntary winding up or a creditors' winding up. In the case of a shareholders' voluntary winding-up, a special resolution of shareholders is required. Seagate-Ireland may also be dissolved by way of court order on the application of a creditor, or by the Companies Registration Office as an enforcement measure where Seagate-Ireland has failed to file certain returns.

        The rights of the shareholders to a return of Seagate-Ireland's assets on dissolution or winding up, following the settlement of all claims of creditors, may be prescribed in Seagate-Ireland's articles of association or the terms of any preferred shares issued by the directors of Seagate-Ireland from time to time. The holders of preferred shares in particular may have the right to priority in a dissolution or winding up of Seagate-Ireland. If the articles of association contain no specific provisions in respect of a dissolution or winding up then, subject to the priorities of any creditors, the assets will be distributed to shareholders in proportion to the paid-up nominal value of the shares held. Seagate-Ireland's articles provide that the ordinary shareholders of Seagate-Ireland are entitled to participate pro rata in a winding up, but their right to do so may be subject to the rights of any preferred shareholders to participate under the terms of any series or class of preferred shares.

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Uncertificated Shares

        Holders of ordinary shares of Seagate-Ireland will not have the right to require Seagate-Ireland to issue certificates for their shares. Seagate-Ireland will only issue uncertificated ordinary shares.

Stock Exchange Listing

        We intend to file an application with the NASDAQ to list the Seagate-Ireland ordinary shares that holders of Seagate-Cayman common shares will receive in the Transaction. We expect that, immediately following the Transaction Time, the Seagate-Ireland ordinary shares will be listed on the NASDAQ under the symbol "STX," the same symbol under which your Seagate-Cayman common shares are currently listed. We do not plan for Seagate-Ireland's ordinary shares to be listed on the Irish Stock Exchange.

No Sinking Fund

        The Seagate-Ireland ordinary shares have no sinking fund provisions.

No Liability for Further Calls or Assessments

        The shares to be issued in the Transaction will be duly and validly issued and fully-paid.

Transfer and Registration of Shares

        Seagate-Ireland's share register will be maintained by its transfer agent. Registration in this share register will be determinative of membership in Seagate-Ireland. A shareholder of Seagate-Ireland who holds shares beneficially will not be the holder of record of such shares. Instead, the depository (for example, Cede & Co., as nominee for DTC) or other nominee will be the holder of record of such shares. Accordingly, a transfer of shares from a person who holds such shares beneficially to a person who also holds such shares beneficially through a depository or other nominee will not be registered in Seagate-Ireland's official share register, as the depository or other nominee will remain the record holder of such shares.

        A written instrument of transfer is required under Irish law in order to register on Seagate-Ireland's official share register any transfer of shares (i) from a person who holds such shares directly to any other person, (ii) from a person who holds such shares beneficially to a person who holds such shares directly, or (iii) from a person who holds such shares beneficially to another person who holds such shares beneficially where the transfer involves a change in the depository or other nominee that is the record owner of the transferred shares. An instrument of transfer also is required for a shareholder who directly holds shares to transfer those shares into his or her own broker account (or vice versa). Such instruments of transfer may give rise to Irish stamp duty, which must be paid prior to registration of the transfer on Seagate-Ireland's official Irish share register. However, a shareholder who directly holds shares may transfer those shares into his or her own broker account (or vice versa) without giving rise to Irish stamp duty provided there is no change in the ultimate beneficial ownership of the shares as a result of the transfer and the transfer is not made in contemplation of a sale of the shares.

        Any transfer of Seagate-Ireland shares that is subject to Irish stamp duty will not be registered in the name of the buyer unless an instrument of transfer is duly stamped and provided to our transfer agent. Seagate-Ireland's articles of association allow Seagate-Ireland, in its absolute discretion, to create an instrument of transfer and pay (or procure the payment of) any stamp duty, which is the legal obligation of a buyer. In the event of any such payment, Seagate-Ireland is (on behalf of itself or its affiliates) entitled to (i) seek reimbursement from the buyer or seller (at its discretion), (ii) set-off the amount of the stamp duty against future dividends payable to the buyer or seller (at its discretion), and (iii) claim a lien against the Seagate-Ireland shares on which it has paid stamp duty. Parties to a share

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transfer may assume that any stamp duty arising in respect of a transaction in Seagate-Ireland shares has been paid unless one or both of such parties is otherwise notified by us.

        Seagate-Ireland's articles of association as they will be in effect after the Transaction delegate to Seagate-Ireland's Secretary the authority to execute an instrument of transfer on behalf of a transferring party.

        In order to help ensure that the official share register is regularly updated to reflect trading of Seagate-Ireland shares occurring through normal electronic systems, we intend to regularly produce any required instruments of transfer in connection with any transactions for which we pay stamp duty (subject to the reimbursement and set-off rights described above). In the event that we notify one or both of the parties to a share transfer that we believe stamp duty is required to be paid in connection with such transfer and that we will not pay such stamp duty, such parties may either themselves arrange for the execution of the required instrument of transfer (and may request a form of instrument of transfer from Seagate-Ireland for this purpose) or request that Seagate-Ireland execute an instrument of transfer on behalf of the transferring party in a form determined by Seagate-Ireland. In either event, if the parties to the share transfer have the instrument of transfer duly stamped (to the extent required) and then provide it to Seagate-Ireland's transfer agent, the buyer will be registered as the legal owner of the relevant shares on Seagate-Ireland's official Irish share register (subject to the matters described below).

        The registration of transfers may be suspended by the directors at such times and for such period, not exceeding in the whole 30 days in each year, as the directors may from time to time determine.

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COMPARISON OF RIGHTS OF SHAREHOLDERS AND
POWERS OF THE BOARD OF DIRECTORS

        Your rights as a common shareholder of Seagate-Cayman and the relative powers of Seagate-Cayman's board of directors are governed by Cayman Islands law and Seagate-Cayman's memorandum and articles of association. After the Transaction, you will become a shareholder of Seagate-Ireland, and your rights and the relative powers of Seagate-Ireland's board of directors will be governed by Irish law and Seagate-Ireland's memorandum and articles of association as they will be in effect after the Transaction.

        Many of the principal attributes of Seagate-Cayman's common shares and Seagate-Ireland's ordinary shares will be similar. However, there are differences between what your rights are under Cayman Islands law and what they will be after the Transaction under Irish law. In addition, there are differences between Seagate-Cayman's memorandum and articles of association and Seagate-Ireland's memorandum and articles of association as they will be in effect after the Transaction, especially as it relates to changes (i) that are required by Irish law (i.e., certain provisions of the Seagate-Cayman articles of association were not replicated in the Seagate-Ireland articles of association because Irish law would not permit such replication, and certain provisions were included in the Seagate-Ireland articles of association although they were not in the Seagate-Cayman articles of association because Irish law requires such provisions to be included in the articles of association of an Irish plc), or (ii) that are necessary in order to preserve the current rights of shareholders and powers of the board of directors of Seagate following the Transaction.

        The following discussion is a summary of material changes in your rights resulting from the Transaction. This summary does not cover all of the differences between Irish law and Cayman Islands law affecting companies and their shareholders or all the differences between Seagate-Cayman's memorandum and articles of association and Seagate-Ireland's memorandum and articles of association. This summary is subject to the complete text of the relevant provisions of the Irish Companies Acts, the Cayman Islands Companies Law, Seagate-Cayman's memorandum and articles of association and Seagate-Ireland's memorandum and articles of association as they will be in effect after the Transaction. We encourage you to read those laws and documents carefully.

        The form of Seagate-Ireland's memorandum and articles of association substantially as they will be in effect after the Transaction are attached as Annex B to this proxy statement. For information as to how you can obtain Seagate-Cayman's memorandum and articles of association, please see "Where You Can Find More Information." Except where otherwise indicated, the discussion of Seagate-Ireland below reflects Seagate-Ireland's memorandum and articles of association as those documents will be in effect upon completion of the Transaction.

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COMPARISON OF CORPORATE GOVERNANCE PROVISIONS

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