---

---

•

the anticipated amount, timing and accounting of revenues, contingent payments, milestone, royalty and other payments under licensing, collaboration or acquisition agreements, tax positions and contingencies, collectability of receivables, pre-approval inventory, cost of sales, research and development costs, compensation and other selling, general and administrative expenses, amortization of intangible assets, foreign currency exchange risk, estimated fair value of assets and liabilities, and impairment assessments;

•	expectations, plans and prospects relating to sales, pricing, growth and launch of our marketed and pipeline products;

•	the potential impact of increased product competition in the markets in which we compete;

•	the spin off of our hemophilia business, including its anticipated benefits, costs and tax treatment;

•	the anticipated amount and timing of payments under the Settlement and License Agreement with Forward Pharma A/S (Forward Pharma) and the timing, outcome and impact of administrative, regulatory, legal and other proceedings related to our patents and other proprietary intellectual property rights under our agreement with Forward Pharma;

•	patent terms, patent term extensions, patent office actions and expected availability and period of regulatory exclusivity;

•	the costs and timing of potential clinical trials, filing and approvals, and the potential therapeutic scope of the development and commercialization of our and our collaborators’ pipeline products;

•	the drivers for growing our business, including our plans and intent to commit resources relating to business development opportunities and research and development programs;

•	potential costs and expenses incurred in connection with corporate restructurings and to execute business transformation and optimization initiatives;

•	our manufacturing capacity, use of third-party contract manufacturing organizations and plans and timing relating to the expansion of our manufacturing capabilities, including anticipated investments and activities in new manufacturing facilities;

•	the expected financial impact of ceasing manufacturing activities and vacating our biologics manufacturing facility in Cambridge, MA and warehouse space in Somerville, MA;

•	the potential impact on our results of operations and liquidity of the United Kingdom's (U.K.'s) intent to voluntarily depart from the European Union (E.U.);

•	the impact of the continued uncertainty of the credit and economic conditions in certain countries in Europe and our collection of accounts receivable in such countries;

•	the potential impact of healthcare reform in the United States (U.S.) and measures being taken worldwide designed to reduce healthcare costs to constrain the overall level of government expenditures, including the impact of pricing actions and reduced reimbursement for our products;

•	the timing, outcome and impact of administrative, regulatory, legal and other proceedings related to patents and other proprietary and intellectual property rights, tax audits, assessments and settlements, pricing matters, sales and promotional practices, product liability and other matters;

•	lease commitments, purchase obligations and the timing and satisfaction of other contractual obligations;

•	our ability to finance our operations and business initiatives and obtain funding for such activities; and

•	the impact of new laws and accounting standards.

---

•	“Biogen,” the “company,” “we,” “us” and “our” refer to Biogen Inc. and its consolidated subsidiaries;

•	“RITUXAN” refers to both RITUXAN (the trade name for rituximab in the U.S., Canada and Japan) and MabThera (the trade name for rituximab outside the U.S., Canada and Japan);

•	"ELOCTATE" refers to both ELOCTATE (the trade name for Antihemophilic Factor (Recombinant), Fc Fusion Protein in the U.S., Canada and Japan) and ELOCTA (the trade name for Antihemophilic Factor (Recombinant), Fc Fusion Protein in the E.U.); and

•	“ANGIOMAX” refers to both ANGIOMAX (the trade name for bivalirudin in the U.S., Canada and Latin America) and ANGIOX (the trade name for bivalirudin in Europe).

---

---

---

---

---

---

---

---

---

---

---

(1)	In addition to patent protection, certain of our products are entitled to regulatory exclusivity in the U.S. and the E.U. expected until the dates set forth below:

(2)	This patent is subject to granted SPCs in certain European countries, which extended the patent term in those countries to 2024.

(3)	This patent was revoked in a European opposition. This decision is being appealed. The patent is subject to granted SPCs in certain European countries, which extended the patent term in those countries to 2029.

(4)	Reflects SPCs granted in most European countries.

(5)	This patent is subject to granted SPCs in certain European countries, which extended the patent term in those countries to 2026.

(6)	This patent is subject to granted SPCs in certain European countries, which extended the patent term in those countries to 2026.

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

•	safety or efficacy issues;

•	the introduction or greater acceptance of competing products;

•	constraints and additional pressures on product pricing or price increases, including those resulting from governmental or regulatory requirements, increased competition, or changes in, or implementation of, reimbursement policies and practices of payors and other third parties; or

•	adverse legal, administrative, regulatory or legislative developments.

•	our limited marketing experience within the spinal muscular atrophy market, which may impact our ability to develop relationships with the associated medical and scientific community;

•	the lack of readiness of healthcare providers to treat patients with spinal muscular atrophy;

•	the effectiveness of our commercial strategy for marketing SPINRAZA; and

•	our ability to maintain a positive reputation among patients, healthcare providers and others in the spinal muscular atrophy community, which may be impacted by pricing and reimbursement decisions relating to SPINRAZA.

•	the introduction of more efficacious, safer, less expensive or more convenient alternatives to our MS products, including our own products and products of our collaborators;

•	the introduction of lower-cost biosimilars, follow-on products or generic versions of branded MS products sold by our competitors, and the possibility of future competition from generic versions or prodrugs of existing therapeutics or from off-label use by physicians of therapies indicated for other conditions to treat MS patients;

---

•	patient dynamics, including the size of the patient population and our ability to attract new patients to our therapies;

•	damage to physician and patient confidence in any of our MS products or to our sales and reputation as a result of label changes or adverse experiences or events that may occur with patients treated with our MS products;

•	inability to obtain appropriate pricing and reimbursement for our MS products compared to our competitors in key international markets; or

•	our ability to obtain and maintain patent, data or market exclusivity for our MS products.

•	changes in, and implementation of, federal, state or foreign government regulations or private third-party payors' reimbursement policies;

•	pressure by employers on private health insurance plans to reduce costs; and

•

consolidation and increasing assertiveness of payors, including managed care organizations, health insurers, pharmacy benefit managers, government health administration authorities, private health insurers and other organizations, seeking price discounts or rebates in connection with the placement of our products on their formularies and, in some cases, the imposition of restrictions on access or coverage of particular drugs or pricing determined based on perceived value.

---

---

---

•

Risk of Product Loss. The manufacturing process for our products is extremely susceptible to product loss due to contamination, oxidation, equipment failure or improper installation or operation of equipment, or vendor or operator error. Even minor deviations from normal manufacturing processes could result in reduced production yields, product defects and other supply disruptions. If microbial, viral or other contaminations are discovered in our products or manufacturing facilities, we may need to close our manufacturing facilities for an extended period of time to investigate and remediate the contaminant.

---

•

Risks of Reliance on Third Parties and Single Source Providers. We rely on third-party suppliers and manufacturers for many aspects of our manufacturing process for our products and product candidates. In some cases, due to the unique manner in which our products are manufactured, we rely on single source providers of several raw materials and manufacturing supplies. These third parties are independent entities subject to their own unique operational and financial risks that are outside of our control. These third parties may not perform their obligations in a timely and cost-effective manner or in compliance with applicable regulations, and they may be unable or unwilling to increase production capacity commensurate with demand for our existing or future products. Finding alternative providers could take a significant amount of time and involve significant expense due to the specialized nature of the services and the need to obtain regulatory approval of any significant changes to our suppliers or manufacturing methods. We cannot be certain that we could reach agreement with alternative providers or that the FDA or other regulatory authorities would approve our use of such alternatives.

•

Global Bulk Supply Risks. We rely on our principal manufacturing facilities for the production of drug substance for our large molecule products and product candidates. Our global bulk supply of these products and product candidates depends on the uninterrupted and efficient operation of these facilities, which could be adversely affected by equipment failures, labor shortages, natural disasters, power failures and numerous other factors.

•

Risks Relating to Compliance with cGMP. We and our third-party providers are generally required to maintain compliance with cGMP and other stringent requirements and are subject to inspections by the FDA and comparable agencies in other jurisdictions to confirm such compliance. Any delay, interruption or other issues that arise in the manufacture, fill-finish, packaging or storage of our products as a result of a failure of our facilities or the facilities or operations of third parties to pass any regulatory agency inspection could significantly impair our ability to develop and commercialize our products. Significant noncompliance could also result in the imposition of monetary penalties or other civil or criminal sanctions and damage our reputation.

•	we may be unable to control the resources our collaborators or third parties devote to our programs or products;

•

disputes may arise under the agreement, including with respect to the achievement and payment of milestones or ownership of rights to technology developed with our collaborators or other third parties, and the underlying contract with our collaborators or other third parties may fail to provide significant protection or may fail to be effectively enforced if the collaborators or third parties fail to perform;

•	the interests of our collaborators or third parties may not always be aligned with our interests, such parties may not pursue regulatory approvals or market a product in the same manner or to the same extent that we would, which could adversely affect our revenues;

•	third-party relationships and collaborations often require the parties to cooperate, and failure to do so effectively could adversely affect product sales, or the clinical development or regulatory approvals of products under joint control or could result in termination of the research, development or commercialization of product candidates or result in litigation or arbitration; and

---

•

any failure on the part of our collaborators or other third parties to comply with applicable laws and regulatory requirements in the marketing, sale and maintenance of the marketing authorization of our products or to fulfill any responsibilities our collaborators or other third parties may have to protect and enforce any intellectual property rights underlying our products could have an adverse effect on our revenues as well as involve us in possible legal proceedings.

---

---

•

new laws, regulations or judicial decisions, or new interpretations of existing laws, regulations or decisions, related to health care availability, pricing or marketing practices, compliance with wage and hour laws and other employment practices, method of delivery, payment for health care products and services, compliance with health information and data privacy and security laws and regulations, tracking and reporting payments and other transfers of value made to physicians and teaching hospitals, extensive anti-bribery and anti-corruption prohibitions, product serialization and labeling requirements and used product take-back requirements;

•	changes in the FDA and foreign regulatory approval processes that may delay or prevent the approval of new products and result in lost market opportunity;

•	requirements that provide for increased transparency of clinical trial results and quality data, such as the EMA’s clinical transparency policy, which could impact our ability to protect trade secrets and competitively-sensitive information contained in approval applications or could be misinterpreted leading to reputational damage, misperception or legal action which could harm our business; and

•	changes in FDA and foreign regulations that may require additional safety monitoring, labeling changes, restrictions on product distribution or use, or other measures after the introduction of our products to market, which could increase our costs of doing business, adversely affect the future permitted uses of approved products, or otherwise adversely affect the market for our products.

---

•	increase our vulnerability to general adverse economic and industry conditions;

•	limit our ability to access capital markets and incur additional debt in the future;

•	require us to dedicate a substantial portion of our cash flow from operations to payments on our indebtedness, thereby reducing the availability of our cash flow for other purposes, including business development efforts, research and development and mergers and acquisitions; and

•	limit our flexibility in planning for, or reacting to, changes in our business and the industry in which we operate, thereby placing us at a competitive disadvantage compared to our competitors that have less debt.

•	the inability to obtain necessary foreign regulatory or pricing approvals of products in a timely manner;

•	collectability of accounts receivable;

•	fluctuations in foreign currency exchange rates, in particular the recent strength of the U.S. dollar versus foreign currencies that has adversely impacted our revenues and net income;

•	difficulties in staffing and managing international operations;

•	the imposition of governmental controls;

•	less favorable intellectual property or other applicable laws;

•	increasingly complex standards for complying with foreign laws and regulations that may differ substantially from country to country and may conflict with corresponding U.S. laws and regulations;

•	the far-reaching anti-bribery and anti-corruption legislation in the U.K., including the U.K. Bribery Act 2010, and elsewhere and escalation of investigations and prosecutions pursuant to such laws;

•	compliance with complex import and export control laws;

•	restrictions on direct investments by foreign entities and trade restrictions;

•	greater political or economic instability; and

•	changes in tax laws and tariffs.

---

•	the cost of restructurings;

•	impairments with respect to investments, fixed assets and long-lived assets, including in-process R&D and other intangible assets;

•	inventory write-downs for failed quality specifications, charges for excess or obsolete inventory and charges for inventory write downs relating to product suspensions, expirations or recalls;

•	changes in the fair value of contingent consideration;

•	bad debt expenses and increased bad debt reserves;

•	outcomes of litigation and other legal or administrative proceedings, regulatory matters and tax matters;

•	milestone payments under license and collaboration agreements; and

•	payments in connection with acquisitions and other business development activities.

•	Reliance on Third Parties. We are dependent on the efforts of Samsung Bioepis and other third parties over whom we have limited or no control in the development and manufacturing of biosimilars products. If Samsung Bioepis or such other third parties fail to perform successfully, we may not realize the anticipated benefits of our investment in Samsung Bioepis;

•	Regulatory Compliance. Biosimilar products may face regulatory hurdles or delays due to the evolving and uncertain regulatory and commercial pathway of biosimilars products in certain jurisdictions;

---

•	Intellectual Property and Regulatory Challenges. Biosimilar products may face extensive patent clearances, patent infringement litigation, injunctions or regulatory challenges, which could prevent the commercial launch of a product or delay it for many years;

•	Failure to Gain Market and Patient Acceptance. Market success of biosimilar products will be adversely affected if patients, physicians and payers do not accept biosimilar products as safe and efficacious products offering a more competitive price or other benefit over existing therapies;

•	Ability to Provide Adequate Supply. Manufacturing biosimilars is complex. If we encounter any manufacturing or supply chain difficulties, we may be unable to meet higher than anticipated demand; and

•

Competitive Challenges. Biosimilar products face significant competition, including from innovator products and from biosimilar products offered by other companies. In some jurisdictions, local tendering processes may restrict biosimilar products from being marketed and sold in those jurisdictions. The number of competitors in a jurisdiction, the timing of approval and the ability to market biosimilar products successfully in a timely and cost-effective matter are additional factors that may impact our success and/or the success of Samsung Bioepis in this business area.

---

---

•	893,000 square feet in Cambridge, Massachusetts, which is comprised of a 67,000 square foot biologics manufacturing facility, which is subleased by Brammer, and 826,000 square feet for our corporate headquarters, laboratory and additional office space; and

•	357,000 square feet of office space in Weston, Massachusetts, of which 175,000 square feet has been subleased through the remaining term of our lease agreement.

•	357,000 square feet of laboratory and office space;

•	175,000 square feet related to a large-scale biologics manufacturing facility;

•	105,000 square feet related to a biologics manufacturing facility;

•	84,000 square feet of warehouse space and utilities;

•	70,000 square feet related to a parenteral fill-finish facility; and

•	43,000 square feet related to a large-scale purification facility.

•	139,000 square feet of warehouse, utilities and support space;

•	70,000 square feet related to a label and packaging facility;

•	50,000 square feet related to a laboratory facility; and

•	47,000 square feet of administrative space.

---

---

---

---

(a)	Product revenues, net reflect the impact of the following product launches:

•	Commercial sales of SPINRAZA began in the fourth quarter of 2016.

---

•	Under the terms of our collaboration agreement with AbbVie, we began to recognize revenues on sales of ZINBRYTA to third parties in the E.U. in the third quarter of 2016.

•	Under the terms of our commercial agreement with Samsung Bioepis, we began to recognize revenues on sales of BENEPALI and FLIXABI to third parties in the E.U. in the first quarter of 2016 and third quarter of 2016, respectively.

•	Commercial sales of ALPROLIX commenced in the second quarter of 2014 and commercial sales of ELOCTATE and PLEGRIDY commenced in the third quarter of 2014.

•	TECFIDERA began in April 2013.

(b)	Notes payable and other financing arrangements reflects the issuance of our senior unsecured notes for an aggregate principal amount of $6.0 billion in September 2015, and the 2013 repayment of our 6.0% notes that were issued in 2008 for an aggregate principal amount of $450.0 million.

(c)	Total Biogen Inc.'s shareholders' equity reflects the repurchase of approximately 32.8 million shares of our common stock at a cost of approximately $8.3 billion between 2012 and 2016:

•	During 2016 we repurchased and retired approximately 3.3 million shares of our common stock at a cost of $1.0 billion under our 2016 Share Repurchase Program.

•	During 2015 we repurchased and retired approximately 16.8 million shares of our common stock at a cost of $5.0 billion under our 2015 Share Repurchase Program.

•	During 2014, 2013 and 2012 we repurchased approximately 2.9 million, 2.0 million and 7.8 million shares, respectively of our common stock at a cost of approximately $2.3 billion under our 2011 Share Repurchase Program of which approximately 3.7 million of these shares were retired.

(d)

Total cost and expenses for the years ended December 31, 2016 and 2015, include restructuring charges of $33.1 million and $93.4 million, respectively. In addition, total cost and expenses for the year ended December 31, 2016, also include charges to cost of sales totaling $52.4 million of expenses incurred as a result of our determination to vacate and cease manufacturing in our small-scale biologics facility in Cambridge, MA as well as vacate our warehouse in Somerville, MA. Total cost and expenses for year ended December 31, 2016, also include $18.1 million of costs incurred directly related to our separation of our hemophilia business into an independent, publicly traded company.

(e)	Total cost and expenses for the year ended December 31, 2016, includes a pre-tax charge of $454.8 million related to the January 2017 settlement and license agreement with Forward Pharma A/S (Forward Pharma).

(f)	In June 2014 AIFA approved a resolution affirming that there is no reimbursement limit from and after February 2013. As a result, we recognized $53.5 million of TYSABRI revenues in the second quarter of 2014 related to the periods beginning February 2013 that were previously deferred.

(g)	Our share of revenues from anti-CD20 therapeutic programs reflects charges of $49.7 million in 2013 for damages and interest awarded to Hoechst in Genentech's arbitration with Hoechst for RITUXAN.

(h)

Commencing in the second quarter of 2013 product and total revenues include 100% of net revenues related to sales of TYSABRI as a result of our acquisition of all remaining rights to TYSABRI from Elan Pharma International, Ltd (Elan), an affiliate of Elan Corporation, plc. Upon the closing, our collaboration agreement was terminated, and we no longer record collaboration profit sharing expense. We recognized collaboration profit sharing expense of $85.4 million and $317.9 million during the years ended December 31, 2013 and 2012, respectively.

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

---

•

Medicaid rebates relate to our estimated obligations to states under established reimbursement arrangements. Rebate accruals are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a liability which is included in other current liabilities. Our liability for Medicaid rebates consists of estimates for claims that a state will make for the current quarter, claims for prior quarters that have been estimated for which an invoice has not been received, invoices received for claims from the prior quarters that have not been paid, and an estimate of potential claims that will be made for inventory that exists in the distribution channel at period end.

•	Governmental rebates or chargebacks, including VA and PHS discounts, represent our estimated obligations resulting from contractual commitments to sell products to qualified healthcare providers at prices lower than the list prices we charge to wholesalers which provide those products. The wholesaler charges us for the

---

•

Managed care rebates represent our estimated obligations to third parties, primarily pharmacy benefit managers. Rebate accruals are recorded in the same period the related revenue is recognized, resulting in a reduction of product revenue and the establishment of a liability which is included in accrued expenses and other current liabilities. These rebates result from performance-based goals, formulary position and price increase limit allowances (price protection). The calculation of the accrual for these rebates is based on an estimate of the customer’s buying patterns and the resulting applicable contractual rebate rate(s) to be earned over a contractual period.

•	Copay assistance represents financial assistance to qualified patients, assisting them with prescription drug co-payments required by insurance. The calculation of the accrual for copay is based on an estimate of claims and the cost per claim that we expect to receive associated with inventory that exists in the distribution channel at period end.

•	Other governmental rebates or applicable allowances primarily relate to mandatory rebates and discounts in international markets where government-sponsored healthcare systems are the primary payors for healthcare.

(i)	our share of pre-tax profits and losses in the U.S. for RITUXAN and GAZYVA;

(ii)	reimbursement of our selling and development expenses in the U.S. for RITUXAN; and

(iii)	revenues on sales in the rest of world for RITUXAN, which consist of our share of pre-tax co-promotion profits on RITUXAN in Canada and royalty revenue on RITUXAN sales outside the U.S. and Canada by the Roche Group and its sublicensees.

---

•	Level 1 — Fair values are determined utilizing quoted prices (unadjusted) in active markets for identical assets or liabilities that we have the ability to access;

•	Level 2 — Fair values are determined by utilizing quoted prices for identical or similar assets and liabilities in active markets or other market observable inputs such as interest rates, yield curves and foreign currency spot rates; and

•	Level 3 — Prices or valuations that require inputs that are both significant to the fair value measurement and unobservable.

---

---

---

---

---

---

---

---

•	In August 2015 the FASB issued ASU No. 2015-14, Revenue from Contracts with Customers (Topic 606): Deferral of the Effective Date, which delayed the effective date of the new standard from January 1, 2017 to January 1, 2018. The FASB also agreed to allow entities to choose to adopt the standard as of the original effective date.

---

•	In March 2016 the FASB issued ASU No. 2016-08, Revenue from Contracts with Customers (Topic 606): Principal versus Agent Considerations, which clarifies the implementation guidance on principal versus agent considerations.

•	In April 2016 the FASB issued ASU No. 2016-10, Revenue from Contracts with Customers (Topic 606): Identifying Performance Obligations and Licensing, which clarifies certain aspects of identifying performance obligations and licensing implementation guidance.

•	In May 2016 the FASB issued ASU No. 2016-12, Revenue from Contracts with Customers (Topic 606): Narrow-Scope Improvements and Practical Expedients related to disclosures of remaining performance obligations, as well as other amendments to guidance on collectability, non-cash consideration and the presentation of sales and other similar taxes collected from customers.

•

In December 2016 the FASB issued ASU No. 2016-20, Technical Corrections and Improvements to Topic 606, Revenue from Contracts with Customers, which amends certain narrow aspects of the guidance issued in ASU 2014-09 including guidance related to the disclosure of remaining performance obligations and prior-period performance obligations, as well as other amendments to the guidance on loan guarantee fees, contract costs, refund liabilities, advertising costs and the clarification of certain examples.

---

---

---

---

---

---

---

•	$60.0 million milestone payment due to Ionis Pharmaceuticals, Inc. (Ionis) for the approval of SPINRAZA in the U.S. in December 2016;

•	$32.0 million in total milestone payments due to AbbVie, Inc. (AbbVie), which became payable upon the approval of ZINBRYTA in the U.S. in May 2016 and the E.U. in July 2016; and

•	$26.5 million upon the approval of ALPROLIX in the E.U. in May 2016 which is comprised of a $20.0 million contingent payment due to the former owners of Syntonix Pharmaceuticals, Inc. (Syntonix) and $6.5 million related to the establishment of a corresponding deferred tax liability.

---

---

---

---

---

---

---

---

---

•	$550.0 million aggregate principal amount of 6.875% Senior Notes due March 1, 2018, valued at 99.184% of par;

•	$1.5 billion aggregate principal amount of 2.90% Senior Notes due September 15, 2020, valued at 99.792% of par;

•	$1.0 billion aggregate principal amount of 3.625% Senior Notes due September 15, 2022, valued at 99.920% of par;

•	$1.75 billion aggregate principal amount of 4.05% Senior Notes due September 15, 2025, valued at 99.764% of par; and

•	$1.75 billion aggregate principal amount of 5.20% Senior Notes due September 15, 2045, valued at 99.294% of par.

---

---

---

---

---

---

---

(a)

MSUs granted in 2016 include approximately 15,000 and 20,000 MSUs issued in 2016 based upon the attainment of performance criteria set for 2013 and 2012, respectively, in relation to awards granted in those years. The remainder of MSUs granted during 2016 include awards granted in conjunction with our annual awards made in February 2016 and MSUs granted in conjunction with the hiring of employees. These grants reflect the target number of shares eligible to be earned at the time of grant.

---

(a)	CSPUs granted in 2016 include awards granted in conjunction with our annual awards made in February 2016 and CSPUs granted in conjunction with the hiring of employees. These grants reflect the target number of shares eligible to be earned at the time of grant.

(a)	PUs granted in 2016 include awards granted in conjunction with our annual awards made in February 2016 and PUs granted in conjunction with the hiring of employees. These grants reflect the target number of shares eligible to be earned at the time of grant.

---

(a)	RSUs granted in 2016 primarily represent RSUs granted in conjunction with our annual awards made in February 2016 and awards made in conjunction with the hiring of new employees. RSUs granted in 2016 also include approximately 11,000 RSUs granted to our Board of Directors.

---

---

---

---

---

---

---

---

---

---

---

(1)	Net revenue represents Biogen’s pre-tax receipts from third-party distributors, less expenses incurred by Biogen in the conduct of commercialization activities supporting the distributor activities.

(2)	The Biogen Distributor Territory represents Biogen territories where sales are derived utilizing a third-party distributor.

---

(3)	A credit will be issued to Sobi against its reimbursement of the Opt-in Consideration for each product in an amount equal to the difference in the rate paid by Biogen to Sobi on sales in the Biogen territories for certain periods prior to the first commercial sale in the Sobi Territory versus the rate that otherwise would have been payable on such sales.

---

---

---

---

---

---

---

---

---

---

---

(1)

Represents sublease income expected to be received for the vacated manufacturing facility in Cambridge, MA, the vacated portion of our Weston, Massachusetts facility and other facilities throughout the world. For additional information related to the sublease of the vacated manufacturing facility in Cambridge, MA, please read Note 3, Restructuring, Business Transformation and Other Cost Savings Initiatives to these consolidated financial statements.

---

---

---

(1)	Represents amounts related to Europe less those attributable to Germany.

---

(a)	Net income and net income attributable to Biogen Inc., for the first quarter of 2016 and the fourth quarter of 2015, includes pre-tax restructuring charges totaling $9.7 million and $93.4 million, respectively related to the 2015 corporate restructuring program.

---

(b)

Net income and net income attributable to Biogen Inc. for the second, third and fourth quarters of 2016 includes pre-tax additional depreciation expense totaling $15.8 million, $15.7 million and $14.0 million, respectively, as part of our determination to cease manufacturing in our small-scale biologics manufacturing facility in Cambridge, MA as well as vacate our warehouse space in Somerville, MA. Our departure from these facilities has shortened the expected useful lives of certain leasehold improvements and other assets at these facilities.

(c)	Net income and net income attributable to Biogen Inc. for the third quarter of 2016 includes a pre-tax charge to research and development expense of $75.0 million for a license fee paid to Ionis as we exercised our option to develop and commercialize SPINRAZA.

(d)	Net income and net income attributable to Biogen Inc. for the fourth quarter of 2016 includes a pre-tax charge to research and development expense of $50.0 million for a milestone payment due to Eisai related to the initiation of a phase 3 trial for E2609.

(e)	Net income and net income attributable to Biogen Inc. for the fourth quarter of 2016 includes a pre-tax charge of $454.8 million related to the January 2017 settlement and license agreement with Forward Pharma.

(f)	Net income and net income attributable to Biogen Inc. for the third quarter of 2015 includes a pre-tax charge to research and development expense of $48.1 million recorded upon entering into the collaboration agreement with AGTC.

(g)	Net income attributable to Biogen Inc. for the third quarter of 2015 reflects the attribution of a $60.0 million charge to noncontrolling interests, net of tax, related to a milestone payment due Neurimmune upon the enrollment of the first patient in a Phase 3 trial for aducanumab.

(h)	Net income and net income attributable to Biogen Inc. for the fourth quarter of 2015 includes a pre-tax charge to research and development expense of $60.0 million recorded upon entering into the collaboration agreement with MTPC.

---

---

---

---