FORM 6-K

SECURITIES AND EXCHANGE COMMISSION

Report of Foreign Private Issuer Pursuant to Rule 13a-16 or 15d-16 of
the Securities Exchange Act of 1934

For the month of April 2005

GEMPLUS INTERNATIONAL S.A.
(Exact name of registrant as specified in its charter)

GEMPLUS INTERNATIONAL S.A.
(Translation of registrant’s name in English)

46A, Avenue J.F. Kennedy
L-1855 Luxembourg
Grand Duchy of Luxembourg
(Address of Principal Executive Offices)

(Indicate by check mark whether the registrant files or will file
annual reports under cover of Form 20-F or Form 40-F.)

(Indicate by check mark whether the registrant by
furnishing the information contained in this form
is also thereby furnishing the information to the
Commission pursuant to Rule 12g3-2(b) under the
Securities Exchange Act of 1934.)

Table of Contents

Gemplus reports strong first quarter 2005 results

First quarter 2005 highlights:

Luxembourg, April 25, 2005 — Gemplus International S.A. (Euronext: LU0121706294 — GEM and NASDAQ: GEMP), the world’s leading provider of smart card solutions, today reported results for the first quarter ended March 31, 2005.

Commenting on the performance for the first quarter 2005, Alex Mandl, President and Chief Executive Officer, said: “This was another quarter of good progress for Gemplus, highlighted by substantial improvement in net income. The slight decrease in sales, reflecting good underlying performance, is caused by the extraordinarily strong sales we had in the quarter a year ago, and does not, in any way, change the positive view we have for the outlook of the year. Demonstrating our commitment to drive innovation for the benefit of our

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customers, we introduced this quarter GemXplore Generations, which is a quantum leap over current SIM technology.”

First quarter 2005 financial review

First quarter 2005 highlights:

Extremely strong sales in the first quarter 2004, which were up 38.8% year-on-year, currency adjusted, led to a slight comparative decrease in sales. Nevertheless, all core businesses saw favorable revenue momentum in the first quarter 2005. This was however mitigated by declines in our mature and peripheral activities.

On a geographical basis, currency adjusted revenue in the Americas rose 2.6% and in EMEA³ by 1.0%, year-on-year, both driven by Wireless. Asia revenue was down 13.6%, currency adjusted, mainly due to China.

Gross margin was up 1.1 percentage points year-on-year, to 32.1%, driven by improvement in product mix, lower chip purchasing prices and volume growth offsetting selling price pressure. The Group also benefited from the results of earlier restructuring and further improvements in the manufacturing cost structure.

Operating expenses⁴ decreased 5.7% year-on-year, to 54.4 million euros. This decrease was mostly driven by a temporary reduction in research and development expenses and no further goodwill amortization. The decrease was despite the cost of stock options and implementation of the Sarbanes-Oxley Act. Operating expenses represented 28.2% of sales during the first quarter, compared to 29.3% a year ago.

As a result, operating income more than doubled, to 7.5 million euros.

Consequently, attributable net income for the first quarter showed strong improvement to 7.2 million euros.

First quarter 2005 highlights:

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The Group’s cash position remains strong and is up 6.7 million euros compared to December 31, 2004, despite restructuring outflows of 3.1 million euros.

Segment analysis

First quarter 2005 highlights:

Wireless revenue continues to show favorable momentum. Extraordinarily strong sales in the first quarter 2004, which were up 70.8% year-on-year, currency adjusted, led to a moderate increase in sales this quarter.

Wireless shipments grew 14% year-on-year, to 68.2 million units. Growth was driven by strong sales in EMEA and Latin America, compensating for lower sales in China.

Wireless product mix continued to improve:

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Wireless average selling price (ASP) was down 9.2% year-on-year and 11.0% quarter-on-quarter, both currency adjusted. Substantial mix improvement did not fully offset strong price pressure, year-on-year.

Wireless gross margin was stable year-on-year, due to lower chip purchasing prices and good progress in manufacturing efficiency, offsetting price pressure.

Telecom gross margin improved 2.4 percentage points year-on-year, due to a more favorable business mix.

Operating expenses decreased 5.2% year-on-year. Correspondingly, operating profit rose 38.5% and the operating margin was up 3.3 percentage points, to 11.4%.

Despite significant EMV growth, revenue was down, due to lower sales in Pay-TV and Metering, and the cannibalization of other payment and conventional cards. Gemplus shipped 12.8 million units of payment microprocessor cards, up 20.0% year-on-year. Payment microprocessor card revenue rose 14.9% year-on-year.

Gross margin was influenced by one-time costs related to reorganization of European manufacturing operations as well as product mix.

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First quarter 2005 highlights:

Revenue was up 5.8% year-on-year, with a strong increase in Enterprise Security projects. In addition, the customer base significantly broadened over the quarter a year ago which was heavily weighted with a single national ID project.

Gemplus’ strategy to focus on selling subsystems based on software components, value-added services and high-end cards led to a significant shift in the sales mix and a large improvement in gross margin.

Outlook

The Group continues to see strong momentum in its core markets. Notwithstanding the apparent slow start in the first quarter, Gemplus expects to increase revenue, excluding acquisitions, by around 10% in 2005, despite continuous selling price pressure.

The Company continues to focus on cost efficiency and is confident of being able to show a very strong improvement of operating income in 2005.

The Group also expects the Financial Services and ID & Security business units to become profitable in 2006.

With all of this, the Group is well on track to realize its mid-term objective of a 10% operating margin in 2007.

Change in accounting policies

Beginning this quarter, foreign exchange gains or losses arising from the Company’s business activities and qualified hedges under IAS 39 are no longer exclusively recorded in cost of sales. Instead, the gains or losses are allocated to the portion of the income statement relating to the underlying currency exposure.

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Starting January 1, 2005, the Company adopted IFRS 2 (issued 2004) “Share-based Payment” and IFRS 3 (issued 2004) “Business Combinations”. Please refer to Note 2.4 “Change in accounting policies” of our 2004 Annual Report for further details.

Business Highlights

Gemplus is supporting operators in overcoming the challenges they face in entering the mobile multimedia age by introducing at this year’s 3GSM World Congress a new extended storage capacity SIM card platform, GemXplore Generations. Since that time, a number of operators have shown great interest in the card, including the French operator, Bouygues Telecom.

This platform, which offers gigabyte storage capacity, flexibility and performance, allows operators to reinforce brand, uniformity of service and subscriber convenience by encouraging new uses for the mobile phone, from Mobile TV, as presented with Nagra and Thales, to storing html web servers, as demonstrated with Orange World.

This quarter saw the involvement of Gemplus in one of the world’s first commercial e-passport deployments: Singapore’s new biometric passport. Gemplus’ contactless e-passport solution, GemBorder, which will be embedded in the passport, will contain biometric information about the passport holder such as fingerprint and facial details. The passport holder can be authenticated against the information on the chip at immigration checkpoints. Gemplus will also supply chip personalization solution and integration service bricks.

In addition, Gemplus delivered over 100,000 GemSCOSTA optical smart cards to the first phase of India’s vehicle registration and drivers’ license program. This program is expected to be the world’s largest of its kind, with a market potential of more than 100 million cards over the next five years.

Earnings calendar

Second quarter 2005 results are scheduled to be reported on July 27, 2005, before the opening of Euronext Paris.

Conference Call:

The company has scheduled a conference call for Monday, 25 April 2005 at 2:00 pm CET (1:00 pm GMT and 8:00 am New-York time). Callers may participate in the live conference call by dialing:

+44 (0) 207 784 1018 or +1 718 354 1171, access code 9245589.

The slide show will be available on the web site at 12:30 CET (11:30 GMT). The webcast will also be available on the IR section of www.gemplus.com.

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Replays of the conference call will be available approximately 5 hours after the conclusion of the conference call until May 9^th, 2005 midnight by dialing:

+44 (0) 207 784 1024 or +1 718 354 11 12, access Code: 9245589.

About Gemplus

Gemplus International S.A. (Euronext: LU0121706294 — GEM and NASDAQ: GEMP) is the world’s leading player in the smart card industry in both revenue and total shipments (source: Gartner-Dataquest (2004), Frost & Sullivan, Datamonitor.). It has sold over 5 billion smart cards.

With security at its core, and 2400 patents produced by its innovative R&D team, Gemplus delivers a wide range of portable, personalized solutions in areas including Identity, Mobile Telecommunications, Public Telephony, Banking, Retail, Transport, Healthcare, WLAN, Pay-TV, e-government, and access control.

Gemplus’ revenue in 2004 was 865 million euros.

www.gemplus.com

For more information:

©2005 Gemplus. All rights reserved. Gemplus, the Gemplus logo, are trademarks and service marks of Gemplus S.A. and are registered in certain countries. All other trademarks and service marks, whether registered or not in specific countries, are the property of their respective owners.

Some of the statements contained in this release constitute forward-looking statements. These statements relate to future events or our future financial performance and involve known and unknown risks, uncertainties, and other factors that may cause our or our industry’s actual results, levels of activity, performance or achievements to be materially different from any future results, levels of activities, performance, or achievements expressed or implied by such forward-looking statements. Actual events or results may differ materially. Although we believe that the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee future results, levels of activity, performance or achievements. Factors that could cause actual results to differ materially from those estimated by the forward-looking statements contained in this release include, but are not limited to: trends in wireless communication and mobile commerce markets; our ability to develop new technology, and the effects of competing technologies developed and expected intense competition generally in our main markets; profitability of our expansion strategy; challenges to or loss of our intellectual property rights; our ability to establish and maintain strategic relationships in our major businesses; our ability to develop and take advantage of new software and services; and the effect of future acquisitions and investments on our share price. Moreover, neither we nor any other person assumes responsibility for the accuracy and completeness of such forward-looking statements. The forward-looking statements contained in this release speak only as of this release. We are under no duty to update any of the forward-looking statements after this date to conform such statements to actual results or to reflect the occurrence of anticipated results.

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Gemplus International SA

Gemplus International SA

Press Release — Financial statements

For the quarterly period ended March 31, 2005

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Gemplus International SA

Consolidated Statements of Income

Due to the adoption of IAS 1 (revised 2003) Presentation of Financial Statements, the Company has modified its Consolidated Balance Sheet and its Consolidated Statement of Income. Please refer to Note 2.23 “Comparatives” of our 2004 Annual Report for further details.

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Gemplus International SA

Consolidated Balance Sheets

Due to the adoption of IAS 1 (revised 2003) Presentation of Financial Statements, the Company has modified its Consolidated Balance Sheet and its Consolidated Statement of Income. Please refer to Note 2.23 “Comparatives” of our 2004 Annual Report for further details.

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Gemplus International SA

Consolidated Statements of Cash Flows

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Gemplus International SA

The consolidated financial statements of the Company have been prepared in accordance with International Financial Reporting Standards (IFRS).

First Quarter 2005 compared with First Quarter 2004

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Gemplus International SA

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

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