Biogen (BIIB) 10-K risk factor changes: FY2023 vs FY2022

- limitations and additional pressures on product pricing or price increases, including those [added: relating to inflation and those] resulting from governmental or regulatory [removed: requirements;] [added: requirements, including those relating to any future potential drug price negotiation under the IRA;] increased competition, including from generic or biosimilar versions of our products; or changes in, or implementation of, reimbursement policies and practices of payors and other third-parties;

- adverse legal, administrative, [added: geopolitical events,] regulatory or legislative developments; [added: or]

- our ability to maintain a positive reputation among patients, healthcare providers and others, which may be impacted by our pricing and reimbursement [removed: decisions; or][added: decisions.]

LEQEMBI [removed: is] [added: and SKYCLARYS are] in the early stages of commercial launch in the U.S. In addition to risks associated with new product launches and the other factors described in these Risk Factors, Biogen’s and Eisai’s ability to successfully commercialize LEQEMBI [added: and our ability to successfully commercialize SKYCLARYS] may be adversely affected due to:

- the effectiveness of Eisai's and Biogen’s commercial strategy for marketing LEQEMBI; [removed: and]

- Eisai’s and Biogen’s ability to maintain a positive reputation among patients, healthcare providers and others in the Alzheimer’s disease community, which may be impacted by pricing and reimbursement decisions relating to LEQEMBI, which are made by [removed: Eisai.][added: Eisai;]

Clinical trials may indicate that our product candidates lack efficacy, have harmful side effects, result in unexpected adverse events or raise other concerns that may significantly reduce [added: or delay] the likelihood of regulatory approval.

Even if we could successfully develop new products or indications, we may make a strategic decision to discontinue development of a product candidate or indication if, for example, we believe commercialization will be difficult relative to the standard of care or we [removed: prefer to pursue] [added: prioritize] other opportunities in our pipeline.

- inability to obtain [added: and maintain] appropriate pricing and adequate reimbursement for our products compared to our competitors in key [removed: international] markets; or

The successful execution of our strategic and growth initiatives may depend upon internal development projects, commercial initiatives and external opportunities, which may include the acquisition and in-licensing of products, [removed: technologies and companies or the entry into strategic alliances and collaborations.]

As such, we are not certain that we will be able to identify suitable candidates for acquisition or if we will be able to reach [removed: agreement.][added: agreement to make any such acquisition if suitable candidates are identified.]

We may fail to initiate or complete transactions for many reasons, including failure to obtain regulatory or other approvals as well as [added: a result of] disputes or litigation.

When a new pharmaceutical product is approved, the availability of government and private reimbursement for that [removed: product] [added: product, diagnosis of the condition it treats and the cost to administer it] may be uncertain, as is the pricing and amount for which that product will be reimbursed.

Our inability to obtain and maintain adequate prices in a particular country may not only limit the revenue from our products within that country but may also adversely affect our ability to secure acceptable prices in existing and potential new markets, which may limit market [removed: growth.][added: growth and result in reductions in revenue.]

[removed: Additionally and in part due to the impact of the COVID-19 pandemic,] [added: Additionally,] in certain jurisdictions governmental health agencies may adjust, retroactively and/or prospectively, reimbursement rates for our products.

New products marketed by our competitors could cause our revenue to decrease due to potential price [added: reductions and lower sales volumes.]

- we may be unable to control the resources our collaborators or third-parties devote to our programs, products or product [removed: candidates;][added: candidates, which may affect our ability to achieve development goals or milestones;]

- the interests of our collaborators or third-parties may not always be aligned with our interests, and such parties may not pursue regulatory approvals or market a product in the same manner or to the same extent [removed: that we would, which could adversely affect our revenue, or may adopt tax strategies that could have an adverse effect on our business, results of operations or financial condition;]

- any failure on the part of our collaborators or third-parties to comply with applicable laws, including tax laws, regulatory requirements and/or applicable contractual obligations or to fulfill any responsibilities they may have to protect and enforce any intellectual property rights underlying our products could have an adverse effect on our revenue [added: or reputation] as well as involve us in possible legal proceedings; and

- any improper conduct or actions on the part of our collaborators or third-parties could subject us to civil or criminal investigations and monetary and injunctive penalties, [added: require management attention,] impact the accuracy and timing of our financial reporting and/or adversely impact our ability to conduct business, our operating results and our reputation.

Legislative and regulatory proposals, enactments to reform health care insurance programs (including those contained in the IRA) and increasing pressure from social sources could significantly [added: influence the manner in which our products are prescribed, purchased and reimbursed.]

For example, provisions of the [removed: Patient Protection and Affordable Care Act (PPACA)] [added: PPACA] have resulted in changes in the way health care is paid for by both governmental and private insurers, including increased rebates owed by manufacturers under the Medicaid Drug Rebate Program, annual fees and taxes on manufacturers of certain branded prescription drugs, the requirement that manufacturers participate in a discount program for certain outpatient drugs under Medicare Part D and the expansion of the number of hospitals eligible for discounts under Section 340B of the Public Health Service Act.

There is [removed: increasing] [added: substantial] public attention on the costs of prescription drugs and we expect drug pricing and other health care costs to continue to be subject to intense political and societal pressures on a global basis.

There is also significant economic pressure on state budgets, [removed: including as a result of the COVID-19 pandemic,] that may result in states increasingly seeking to achieve budget savings through mechanisms that limit coverage or payment for our drugs.

State Medicaid programs are [removed: increasingly] requesting manufacturers to pay supplemental rebates and requiring prior authorization by the state program for use of any drug for which supplemental rebates are not being paid.

Many countries have announced or implemented measures, and may in the future implement new or additional measures, to reduce health care costs to limit the overall level of government [removed: expenditures.]

If these third-parties fail to perform successfully, [added: or reduce their third party manufacturing production,] our biosimilar product development or commercialization of biosimilar products could be delayed, revenue from biosimilar products could decline and/or we may not realize the anticipated benefits of these arrangements;

We are dependent on a third-party for the manufacture of our biosimilar products and such third-party may not perform its obligations in a timely and [added: cost-effective manner or in compliance with applicable regulations and may be unable or unwilling to increase production capacity commensurate with demand for our existing or future biosimilar products;]

- *Intellectual Property and Regulatory Challenges.* Biosimilar products may face extensive [removed: patent clearances, patent] [added: intellectual property clearances and] infringement litigation, injunctions or regulatory challenges, which could prevent the commercial launch of a product or delay it for many years or result in imposition of monetary damages, penalties or other civil sanctions and damage our reputation;

We may fail to [removed: obtain] [added: obtain, defend] or preserve patent and other intellectual property rights, including certain regulatory forms of exclusivity, or the protection we obtain may not be of sufficient breadth and degree to protect our commercial interests in all countries where we conduct business, which could result in financial, business or reputational harm to us or could cause a decline or volatility in our stock price.

Even if later stage clinical trials are successful, [added: regulatory authorities may delay or decline approval of our product candidates.]

One CRO has responsibility for a substantial portion of our activities and reporting related to our clinical [removed: trials, adversely affect our expense associated with such] trials and if such CRO does not adequately perform, many of our trials may be [removed: affected.][added: affected, including adversely affecting our expenses associated with such trials.]

[removed: Discovery of safety issues with our products could create product liability and could cause additional regulatory scrutiny and] requirements for additional labeling or safety monitoring, withdrawal of products from the market and/or the imposition of fines or criminal penalties.

A breakdown or breach of our [removed: technology] [added: information] systems could subject us to liability or interrupt the operation of our business.

We are increasingly dependent upon [removed: technology] [added: information] systems and data to operate our business.

[removed: The COVID-19 pandemic has] [added: Changes in how we operate have] caused us to modify our business practices in ways that heighten this dependence, including changing the requirement that most of our office-based employees in the U.S. and our other key markets work from the office, with [removed: a number] [added: many] of our employees now working in hybrid or full-remote positions.

As a result, we are increasingly dependent upon our [removed: technology] [added: information] systems to operate our business and our ability to effectively manage our business depends on the security, reliability and adequacy of our [removed: technology] [added: information] systems and data, which includes use of cloud technologies, including Software as a Service (SaaS), Platform as a Service (PaaS) and Infrastructure as a Service (IaaS).

[removed: Breakdowns, invasions, corruptions, destructions and/or breaches of our technology systems or those of our business partners, including our cloud technologies,] [added: nologies,] and/or unauthorized access to our data and information could subject us to [added: significant] liability, negatively impact our business operations, and/or require replacement of technology and/or [added: sizeable] ransom payments.

Our [removed: technology] [added: information] systems, including our cloud technologies, continue to increase in multitude and complexity, increasing our vulnerability when breakdowns, malicious intrusions and random attacks occur.

[added: Data] privacy or security breaches also pose a risk that sensitive data, including intellectual property, trade secrets or personal information belonging to us, patients, customers or other business partners, may be exposed to unauthorized persons or to the public.

- requirements such as participation in a registry and the use of imaging or other diagnostics for LEQEMBI;

- our ability to obtain approval in other markets;

- the approval of other new products for the same or similar indications;

- Biogen's ability to obtain and maintain adequate reimbursement for SKYCLARYS; and

- the effectiveness of Biogen's commercial strategy for marketing SKYCLARYS.

For example, we are currently seeking approval of SKYCLARYS in Europe and any delays or challenges regarding its approval in Europe may adversely impact our ability to realize the anticipated benefits from the Reata acquisition.

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technologies, companies, the entry into strategic alliances and collaborations or our Fit for Growth program, as well as our ability to execute on previously-announced initiatives such as the exploration of strategic options for our biosimilars business.

For example, we recently acquired Reata and are in the process of integrating Reata into our Company.

The ultimate success of our acquisition of Reata and our ability to realize the anticipated benefits from the acquisition, including the SKYCLARYS product and anticipated synergies, depends on, among other things, how effective we are in integrating the Biogen and Reata operations.

We face risks associated with our Fit for Growth program that may impair our ability to achieve anticipated savings and operational efficiencies or that may otherwise harm our business.

These risks include delays in implementation of cost optimization actions, loss of workforce capabilities, higher than anticipated separation expenses, litigation and the failure to meet financial and operational targets.

In addition, the calculation of the anticipated cost savings and other benefits resulting from our Fit for Growth program are subject to many estimates and assumptions.

These estimates and assumptions are subject to significant business, economic, competitive and other uncertainties and contingencies, many of which are beyond our control.

if these estimates and assumptions are incorrect or if we experience delays or unforeseen events, our business and financial results could be adversely affected.

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Reimbursement for our products by governments, including the timing of any reimbursements, may also be affected by budgetary or political constraints, particularly in challenging economic environments.

Government agencies often do not set their own budgets and therefore, have limited control over the amount of money they can spend.

In addition, these agencies experience political pressure that may dictate the manner in which they spend money.

There can be no assurance that the economic, budgeting or political issues will not worsen and adversely impact sales or reimbursements of our products.

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that we would, which could adversely affect our revenue, or may adopt tax strategies that could have an adverse effect on our business, results of operations or financial condition;

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expenditures.

For example, a recently announced potential acquisition of a contract development and manufacturing organization by a third party.

The decision to explore strategic options related to our biosimilars business could adversely affect our operations related to our biosimilars business.

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Discovery of safety issues with our products could create product liability and could cause additional regulatory scrutiny and

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Breakdowns, invasions, corruptions, destructions and/or breaches, which impact may include, but not limited to, comprising the capacity, reliability or security of our information systems or those of our business partners, including our cloud tech

Recent developments in the threat landscape include use of AI and machine learning, as well as an increased number of cyber extortion attacks, with higher financial ransom demand amounts and increasing sophistication and variety of ransomware techniques and methodology.

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Regulations continue to change as regulators worldwide consider new rules.

For example, a recently announced potential acquisition of a contract development and manufacturing organization by a third party.

Such developments could increase our

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Additionally, we are building a new gene therapy manufacturing facility in RTP, North Carolina with no assurance that this investment will be fully utilized.

- the inability or reluctance of patients to receive a diagnosis, prescription or administration of our products or a decision to prescribe and administer competitive therapies as a direct or indirect result of the COVID-19 pandemic.

The FDA may withdraw approval if Eisai and Biogen fail to comply with the conditions of the accelerated approval.

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reductions and lower sales volumes.

influence the manner in which our products are prescribed, purchased and reimbursed.

For example, two committees of the U.S. House of Representatives previously investigated the approval and price of ADUHELM.

cost-effective manner or in compliance with applicable regulations and may be unable or unwilling to increase production capacity commensurate with demand for our existing or future biosimilar products;

regulatory authorities may delay or decline approval of our product candidates.

Data

Regulators are considering new cyber security regulations.

Our interactions with physicians and other health

We may also be required

The ongoing COVID-19 pandemic and other global health outbreaks may, directly or indirectly, adversely affect our business, results of operations and financial condition.

Our business has and could continue to be adversely affected, directly or indirectly, by the ongoing COVID-19 pandemic and other global health outbreaks.

We continue to monitor our operations and applicable government recommendations, and we have made modifications to our normal operations because of the COVID-19 pandemic and other global health outbreaks, including limiting travel and adopting flexible working arrangements.

Customer-facing professionals interactions in healthcare settings have changed as a result of the COVID-19 pandemic and other global health outbreaks.

This limits our ability to market our products and educate physicians, which, in turn, could have an adverse effect on our ability to compete in the marketing and sales of our products.

Changes in flexible working arrangements could impact employee retention, employees' productivity and morale, strain our technology resources and introduce operational risks.

Additionally, the risk of cyber-attacks or other privacy or data security incidents may be heightened as a result of our moving increasingly towards a remote working environment, which may be less secure and more susceptible to hacking attacks.

The COVID-19 pandemic and other global health outbreaks could affect the health and availability of our workforce as well as those of the third-parties we rely on.

Furthermore, delays and disruptions experienced by our collaborators or other third-parties due to the COVID-19 pandemic and other global health outbreaks could adversely impact the ability of such parties to fulfill their obligations, which could affect product sales or the clinical development or regulatory approvals of product candidates under joint control.

Our ability to continue our existing clinical trials or to initiate new clinical trials has been and may continue to be adversely affected, directly or indirectly, by the COVID-19 pandemic and other global health outbreaks.

Restrictions on travel and/or transport of clinical materials as well as diversion of hospital staff and resources to COVID-19 infected patients could disrupt trial operations and recruitment, possibly resulting in a slowdown in enrollment and/or deviations from or disruptions in key clinical trial activities, such as clinical trial site monitoring.

These challenges may lead to difficulties in meeting protocol-specified procedures.

We may need to make certain adjustments to the operation of clinical trials in an effort to minimize risks to trial data integrity during the COVID-19 pandemic and other global health outbreaks.

In addition, the impact of the COVID-19 pandemic and other global health outbreaks on the operations of the FDA and other health authorities may delay potential approvals of our product candidates.

State and federal healthcare reform measures have been adopted in the past, and may be adopted in the future, any of which could limit the amounts that federal and state governments will pay for healthcare products and services, which could result in reduced demand for our products or additional pricing pressures and have a financial impact on our business that we cannot predict.

While it is not possible at this time to estimate the entirety of the impact that the COVID-19 pandemic and other global health outbreaks will continue to have on our business, the broad impact of the pandemic on all business activities may materially and adversely affect our business, supply chain and distribution systems, results of operations and financial condition.

applicable to our business.

affect our earnings.

Our effective tax rate may be different than experienced in the past or our current expectations due to many factors, including changes in the mix of our

For example, the SEC has proposed amendments to its disclosure rules regarding climate-related disclosure requirements.

For our discussion of the year ended December 31, [removed: 2021,] [added: 2022,] compared to the year ended December 31, [removed: 2020,] [added: 2021,] please read *Item 7.* *Management's Discussion and Analysis of Financial Condition and Results of Operations* located in our Annual Report on Form 10-K for the year ended December 31, [removed: 2021.][added: 2022.]

We have a broad portfolio of medicines to treat MS, have introduced the first approved treatment for [removed: SMA and] [added: SMA,] co-developed [removed: two] treatments to address a defining pathology of Alzheimer’s [removed: disease.][added: disease and launched the first approved treatment to target a genetic cause of ALS.]

We are focused on advancing our pipeline in neurology, [removed: neuropsychiatry,] specialized immunology and rare diseases.

Our marketed products include TECFIDERA, VUMERITY, AVONEX, PLEGRIDY, TYSABRI and FAMPYRA for the treatment of MS; SPINRAZA for the treatment of SMA; [removed: ADUHELM] [added: SKYCLARYS] for the treatment of [removed: Alzheimer's disease;] [added: Friedreich's Ataxia; QALSODY for the treatment of ALS;] and FUMADERM for the treatment of severe plaque psoriasis.

[removed: We also collaborate with Eisai on] [added: In July 2023] the [removed: commercialization] [added: FDA granted traditional approval] of [removed: LEQEMBI] [added: LEQEMBI, an anti-amyloid antibody] for the treatment of Alzheimer's disease, which was [added: previously] granted accelerated approval by the FDA in January 2023.

We [added: also] have [added: collaborations with Eisai on the commercialization of LEQEMBI for the treatment of Alzheimer's disease and Sage on the commercialization of ZURZUVAE for the treatment of PPD and we have] certain business and financial rights with respect to RITUXAN for the treatment of non-Hodgkin's lymphoma, CLL and other conditions; RITUXAN HYCELA for the treatment of non-Hodgkin's lymphoma and CLL; GAZYVA for the treatment of CLL and follicular lymphoma; OCREVUS for the treatment of PPMS and RMS; LUNSUMIO [removed: (mosunetuzumab), which was granted accelerated approval in the U.S. during the fourth quarter of 2022] for the treatment of relapsed or refractory follicular lymphoma; [removed: glofitamab, an investigational] [added: COLUMVI, a] bispecific antibody for the [removed: potential] treatment of non-Hodgkin's lymphoma; and have the option to add other potential anti-CD20 therapies, pursuant to our collaboration arrangements with Genentech, a wholly-owned member of the Roche Group.

We [removed: also] commercialize [added: a portfolio of] biosimilars of advanced biologics including BENEPALI, an etanercept biosimilar referencing ENBREL, IMRALDI, an adalimumab biosimilar referencing HUMIRA, and FLIXABI, an infliximab biosimilar referencing REMICADE, in certain countries in Europe, as well as BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, in the U.S. [removed: We continue to develop potential biosimilar products including BIIB800, a proposed tocilizumab biosimilar referencing ACTEMRA,] and [removed: SB15, a proposed aflibercept biosimilar referencing EYLEA.][added: certain international markets.]

For additional information on our collaboration [removed: arrangements,] [added: arrangements with Ionis,] please read *Note 19, Collaborative and Other Relationships*, to our consolidated financial statements included in this report.

In order to support our future growth and drug development pipeline, we [removed: are expanding] [added: expanded] our large molecule production capacity [removed: by building] [added: and built] a large-scale biologics manufacturing facility in Solothurn, Switzerland.

In the second quarter of 2021 a portion of the facility [added: (the first manufacturing suite)] received a GMP multi-product license from [removed: SWISSMEDIC.][added: the SWISSMEDIC and was placed into service.]

We believe that the Solothurn facility will support our anticipated [removed: near-term] [added: near to mid-term] needs for the manufacturing of biologic [removed: assets.][added: assets, including the commercial launch of LEQEMBI.]

If we are unable to fully utilize our manufacturing facilities, [removed: due to lower than forecasted demand for our products,] we will incur [added: additional] excess capacity charges which [removed: will] [added: would] have a negative effect on our financial condition and results of operations.

In the longer term, our revenue growth will depend upon the successful clinical development, regulatory approval and launch of new commercial [added: products as well as additional indications for our existing products, our ability to obtain]

[removed: products as well as additional indications for our existing products, our ability to obtain] and maintain patents and other rights related to our marketed products, assets originating from our research and development efforts and/or successful execution of external business development opportunities.

[removed: During the first quarter of 2022,] [added: The increase was partially offset by a decrease in excess and obsolescence inventory charges] as [added: 2022 included] a [removed: result] [added: write-off] of [removed: the final NCD, we recorded] approximately $275.0 million [removed: of charges associated with] [added: during] the [removed: write-off] [added: first quarter] of [added: 2022 of excess] inventory and [removed: purchase] [added: contractual] commitments [removed: in excess of forecasted demand] related to ADUHELM.

[removed: Additionally, for] [added: For] the [removed: year] [added: years] ended December 31, [added: 2023 and] 2022, we recorded approximately [removed: $111.0] [added: $165.2] million [added: and $119.0 million, respectively,] of aggregate gross idle capacity [removed: charges related to ADUHELM.][added: charges.]

[removed: These charges were] [added: Neurimmune of approximately $3.0 million, which was] recorded in [removed: cost of sales] [added: other (income) expense, net] within our consolidated statements of income for the year ended December 31, [removed: 2022.][added: 2023.]

We [removed: have] [added: also] recognized approximately $197.0 million related to Eisai's 45.0% share of inventory, idle capacity charges and contractual commitments in collaboration profit [removed: (loss) sharing][added: sharing/(loss reimbursement) within our consolidated statements of income for the year ended December 31, 2022.]

[added: This sale resulted in a pre-tax gain on sale of approximately $503.7 million, net of transaction costs, which is reflected] within [added: gain on sale of building in] our consolidated statements of income for the year ended December 31, 2022.

[removed: *TECFIDERA*][added: TECFIDERA]

For additional information, please read *Note 21, Litigation*, to our consolidated financial statements included in this [removed: report and the discussion under *Results of Operations - Product Revenue - Multiple Sclerosis (MS) - Fumarate* below.][added: report.]

[removed: *Business Update Regarding COVID-19 and Other Disruptions*][added: BUSINESS UPDATE REGARDING MACROECONOMIC CONDITIONS AND OTHER DISRUPTIONS]

[removed: *Geopolitical Tensions*][added: GEOPOLITICAL TENSIONS]

The ongoing geopolitical tensions related to Russia's invasion of Ukraine [added: and the recent military conflict in the Middle East] have resulted in global business disruptions and economic [removed: volatility, including sanctions and other restrictions levied on the government and businesses in Russia.][added: volatility.]

Although we do not have affiliates or employees, in either Russia or Ukraine, we do provide various therapies to patients in Russia through a [removed: distributor and are currently involved in clinical trials with sites in Ukraine and Russia.][added: distributor.]

[removed: In addition, new government sanctions on the export of certain] manufacturing materials to Russia may delay or limit our ability to get new products approved.

The impact of the conflict on our operations and financial performance remains uncertain and will depend on future developments, including the severity and duration of the [removed: conflict,] [added: conflict between Russia and Ukraine,] its impact on regional and global economic conditions and whether the conflict spreads or has effects on countries outside Ukraine and Russia.

Revenue generated from sales in [removed: these regions represented] [added: Russia and Ukraine represent] less than 2.0% of total [removed: product] revenue for the years ended December 31, [added: 2023,] 2022 and 2021.

We will continue to monitor the ongoing conflict between Russia and Ukraine [added: as well as the military conflict in the Middle East] and assess any potential impacts on our business, supply chain, partners or customers, as well as any factors that could have an adverse effect on our results of operations.

Factors such as [removed: the COVID-19 pandemic and other] global health outbreaks, adverse weather events, geopolitical events, [added: inflation,] labor or raw material shortages and other supply chain disruptions could result in product shortages or other difficulties and delays or increased costs in manufacturing our products.

[removed: *Inflation Reduction Act of 2022*][added: INFLATION REDUCTION ACT OF 2022]

The provisions of the IRA [removed: will be] [added: are] effective for periods after December 31, 2022.

The [removed: enactment of the] IRA did not result in any material adjustments to our income tax provision or [removed: net deferred] [added: other income] tax [removed: assets] [added: balances] as of December 31, [added: 2023 and] 2022.

We [removed: expect additional guidance and regulations to be issued in future periods and] will continue to assess its potential impact on our business and results of operations as further information becomes available.

[removed: Financial Highlights][added: FINANCIAL HIGHLIGHTS]

As described below under *Results of Operations*, our net income and diluted earnings per share attributable to Biogen Inc. for the year ended December 31, [removed: 2022,] [added: 2023,] compared to the year ended December 31, [removed: 2021,] [added: 2022,] reflects the following:

[removed: *Revenue*][added: | TOTAL REVENUE | | | | | |]

[removed: ◦The] [added: - The] decrease in MS product revenue [removed: of $666.5 million, or 10.9%, from $6,096.7 million in 2021 to $5,430.2 million in 2022,] was primarily due to a decrease in TECFIDERA demand as a result of multiple TECFIDERA generic entrants in North America, Brazil and certain E.U. countries, [removed: and] a decrease in Interferon demand due to competition as patients transition to higher efficacy [added: therapies] and [removed: oral MS therapies.][added: a decrease in U.S. TYSABRI revenue primarily driven by increased competition and pricing pressure.]

[removed: ◦The] [added: The increase was partially offset by a] decrease in [added: rest of world] SPINRAZA revenue [removed: of $111.6 million, or 5.9%, from $1,905.1 million in 2021 to $1,793.5 million in 2022, was] primarily due to [removed: country mix,] the unfavorable impact of foreign currency [removed: exchange] [added: exchange, increased competition, a decrease in pricing] and the timing of [removed: shipments, partially offset by an increase in sales volumes.][added: shipments.]

[removed: ◦The decrease in revenue from our biosimilar business of $80.0 million, or 9.6%, from $831.1 million in 2021] [added: - For 2023 compared] to [removed: $751.1 million in] 2022, [added: the increase in biosimilar revenue] was primarily due to [added: an increase in sales volumes related to the continued launch of BYOOVIZ in the U.S. and rest of world, partially offset by] unfavorable [added: BYOOVIZ] pricing and the unfavorable impact of foreign currency [removed: exchange, partially offset by an increase in sales volumes.][added: exchange.]

Through our 2023 acquisition of Reata we market the first and only drug approved in the U.S. and the E.U. for the treatment of Friedreich's Ataxia in adults and adolescents aged 16 years and older.

We also have exclusive rights to commercialize TOFIDENCE, a tocilizumab biosimilar referencing ACTEMRA.

We continue to develop potential biosimilar product SB15, a proposed aflibercept biosimilar referencing EYLEA.

The second manufacturing suite became operational in January 2024.

The plant represents a significant increase in our overall manufacturing capacity and is not yet being fully utilized, resulting in our recording of excess capacity charges.

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Following a favorable March 2023 decision of the CJEU affirming TECFIDERA's right to regulatory data and marketing protection and the EC determination in May 2023 that TECFIDERA is entitled to an additional year of market protection for its pediatric indication, we believe that TECFIDERA is entitled to regulatory marketing protection in the E.U. until at least February 2, 2025, and are seeking to enforce this protection.

In December 2023, the EC revoked all centralized marketing authorizations for generic versions of TECFIDERA.

As of December 31, 2023, some of the TECFIDERA generics have not yet fully exited some E.U. markets and we expect removal of all generics from the market will take additional time.

We are closely monitoring this situation and working to enforce our legal right to market protection.

In addition, we will continue to enforce our EP 2 653 873 patent related to TECFIDERA, which expires in 2028.

Significant portions of our business are conducted in Europe, Asia and other international geographies.

Additionally, global disputes and interruptions in international relationships, including tariffs, trade protection measures, import or export licensing requirements and the imposition of trade sanctions or similar restrictions by the U.S. or other governments, affect our ability to do business.

For example, tensions between the U.S. and China have led to a series of tariffs and sanctions being imposed by the U.S. on imports from China mainland, as well as other business restrictions.

CURRENT ECONOMIC CONDITIONS

Economic conditions remain vulnerable as markets continue to be impacted in part by elevated inflation, rising interest rates, global supply chain constraints and recent bank failures.

During 2023 concerns arose with respect to the financial condition of certain banking institutions in the U.S., in particular those with exposure to certain types of depositors and large portfolios of investment securities.

In March 2023 two such banks were closed and taken over by the FDIC, which created significant market disruption.

While we did not have any direct exposure to these institutions, we do maintain our cash at financial institutions, often in balances that exceed the current FDIC insurance limits, and will continue to monitor our cash, cash equivalents and investments and take steps to identify any potential impact and minimize any disruptions on our business.

If other banks and financial institutions enter receivership or become insolvent in the future due to financial conditions affecting the banking system and financial markets, our ability to access our cash, cash equivalents and investments, including transferring funds, making payments or receiving funds, may be threatened and could have a material adverse effect on our business and financial condition.

For example, sanctions and other restrictions have been levied on the government and businesses in Russia.

In addition, new government sanctions on the export of certain

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Revenue generated from sales in the broader Middle East region represents less than 2.0% of total revenue for the years ended December 31, 2023, 2022 and 2021.

Preliminary guidance has been issued by the IRS and we expect additional guidance and regulations to be issued in future periods.

The IRA's drug pricing controls and Medicare redesign may have an adverse impact on our sales (particularly for our products that are more substantially reliant on Medicare reimbursement), our business and our results of operations.

However, the degree of impact from this legislation on our business depends on a number of implementation decisions.

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| | | | | | |

| --- | --- | --- | --- | --- | --- |

Decreased

$337.8 million or 3.3%

| | | | | | |

| --- | --- | --- | --- | --- | --- |

| DILUTED EARNINGS PER SHARE | | | | | |

Decreased

$12.90 or 61.8%

| | | | | | |

| --- | --- | --- | --- | --- | --- |

Decreased

In addition to continuing to invest in new potential innovation in MS and SMA we are advancing our mid-to-late stage programs including zuranolone for MDD and PPD, BIIB080 for Alzheimer's disease, tofersen for ALS and both litifilimab and dapirolizumab pegol for certain forms of lupus.

We estimate the second manufacturing suite at the Solothurn facility will be operational by the end of 2023.

Our revenue depends upon continued sales of our products as well as the financial rights we have in our anti-CD20 therapeutic programs, and, unless we develop, acquire rights to and/or commercialize new products and technologies, we will be substantially dependent on sales from our products and our financial rights in our anti-CD20 therapeutic programs for many years.

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*ADUHELM (aducanumab)*

*U.S.*

In June 2021 the FDA granted accelerated approval of ADUHELM, which, until March of 2022, we had been collaborating on with Eisai, based on reduction in amyloid beta plaques observed in patients treated with ADUHELM.

As part of the accelerated approval, we are required to conduct a confirmatory trial to verify the clinical benefit of ADUHELM in patients with Alzheimer’s disease.

The FDA may withdraw approval if, among other things, the confirmatory trial fails to verify clinical benefit of ADUHELM, ADUHELM's benefit-risk is no longer positive or we fail to comply with the conditions of the accelerated approval.

In April 2022 the CMS released a final NCD for the class of anti-amyloid treatments in Alzheimer's disease, including ADUHELM.

The final NCD confirmed coverage with evidence development, in which patients with Medicare can only access treatment if they are part of an approved clinical trial.

This decision effectively resulted in denying all Medicare beneficiaries access to ADUHELM.

We expect that this decision will reduce future demand for ADUHELM to a minimal level.

Additionally, as a result of the final NCD we have substantially eliminated our commercial infrastructure supporting ADUHELM, retaining minimal resources to manage patient access programs, including a continued free drug program for patients currently on treatment in the U.S.

We expect to continue funding certain regulatory and research and development activities for ADUHELM, including the continuation of the EMBARK re-dosing study and the Phase 4 post-marketing requirement study, ENVISION.

Additional actions regarding ADUHELM may be informed by upcoming data readouts expected for this class of antibodies, as well as further engagement with the FDA and CMS.

On March 14, 2022, we amended our ADUHELM Collaboration Agreement with Eisai.

As of the amendment date, we have sole decision making and commercialization rights worldwide on ADUHELM, and beginning January 1, 2023, Eisai receives only a tiered royalty based on net sales of ADUHELM, and no longer participates in sharing ADUHELM's global profits and losses.

Eisai's share of development, commercialization and manufacturing expense was limited to $335.0 million for the period from January 1, 2022 to December 31, 2022, which was achieved as of December 31, 2022.

Once this limit was achieved, we became responsible for all ADUHELM related costs.

In October 2020 the EMA accepted for review the MAA for aducanumab and in December 2020 the Ministry of Health, Labor and Welfare (MHLW) accepted for review the Japanese NDA for aducanumab.

In December 2021 the CHMP of the EMA adopted a negative opinion on the MAA for aducanumab in Europe.

We sought re-examination of the opinion by the CHMP.

In April 2022 we announced our decision to withdraw our MAA for aducanumab in Europe.

In the E.U., we are seeking to enforce a patent granted in June 2022 that relates to TECFIDERA and expires in 2028.

In addition, we are litigating to affirm that TECFIDERA is entitled to regulatory data and

market protection until at least February 2024.

Our Company, the EMA and the EC have each appealed the May 2021 decision of the European General Court, which annulled the EMA's decision not to validate an application for approval of a TECFIDERA generic on the basis that the EMA and EC conducted the wrong assessment when determining TECFIDERA's entitlement to regulatory data and marketing protection.

Our Company, the EMA and the EC have each appealed the General Court’s decision as wrongly decided and the appeal is pending.

On October 6, 2022, the Advocate General of the CJEU issued a nonbinding advisory opinion in Biogen's favor.

This opinion recommends that the CJEU set aside the judgment of the European General Court.

We are awaiting the decision of the CJEU.

*COVID-19*

The COVID-19 pandemic continues to present a substantial public health and economic challenge around the world.

The length of time and full extent to which the COVID-19 pandemic directly or indirectly impacts our business, results of operations and financial condition, including sales, expense, reserves and allowances, the supply chain, manufacturing, clinical trials, research and development costs and employee-related costs, depends on future developments that are highly uncertain, subject to change and are difficult to predict, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain or treat COVID-19 as well as the economic impact on local, regional, national and international customers and markets.

We are monitoring the demand for our products, including the duration and degree to which we may see delays in starting new patients on a product due to hospitals diverting the resources that are necessary to administer certain of our products to care for COVID-19 patients, including products, such as TYSABRI and SPINRAZA, that are administered in a physician's office or hospital setting.

We may also see reduced demand for immunosuppressant therapies during the COVID-19 pandemic.

While we are currently continuing the clinical trials we have underway in sites across the globe, COVID-19 precautions have impacted the timeline for some of our clinical trials and these precautions may,

directly or indirectly, have a further impact on timing in the future.

The timing and costs of these trials may be impacted as a result of the conflict.

We are subject to certain risks that may affect our results of operations, cash flow and fair values of assets and liabilities, including volatility in foreign currency exchange rates, interest rate movements and equity price exposure as well as changes in economic conditions in the markets in which we operate as a result of the [removed: COVID-19 pandemic] [added: conflict between Russia] and [added: Ukraine and] the [added: military] conflict in [removed: Ukraine.][added: the Middle East.]

We manage the impact of foreign currency exchange rates and interest rates through various financial instruments, including derivative instruments such as foreign currency forward contracts, [added: foreign currency options,] interest rate lock contracts and interest rate swap contracts.

[removed: Foreign Currency Exchange Risk][added: FOREIGN CURRENCY EXCHANGE RISK]

As a result, our consolidated financial position, results of operations and cash flow can be affected by market fluctuations in foreign currency exchange rates, primarily with respect to the Euro, British pound sterling, Canadian [removed: dollar, Swiss franc] [added: dollar] and [removed: Japanese yen.][added: Swiss franc.]

The impact to net income as a result of a strengthening U.S. dollar will be partially [added: mitigated by the value of non-U.S. expense, which will also decline when reported in U.S. dollars.]

This categorization did not have a material impact on our results of operations or financial position as of December 31, [removed: 2022,] [added: 2023,] and is not expected to have a material impact on our results of operations or financial position in the future.

[removed: *Revenue and Operating Expense Hedging Program*][added: REVENUE AND OPERATING EXPENSE HEDGING PROGRAM]

We use foreign currency forward contracts and foreign currency options to manage foreign currency risk, with the majority of our forward contracts [added: and options] used to hedge certain forecasted revenue and operating expense transactions denominated in foreign currencies in the next 12 months.

[removed: *Balance Sheet Risk Management Hedging Program*][added: BALANCE SHEET RISK MANAGEMENT HEDGING PROGRAM]

In these instances, we principally utilize currency forward [added: contracts.]

As of December 31, [removed: 2022] [added: 2023] and [removed: 2021,] [added: 2022,] a hypothetical adverse 10.0% movement in foreign currency exchange rates compared to the U.S. dollar across all maturities would result in a hypothetical decrease in the fair value of forward contracts of approximately [removed: $293.7] [added: $249.4] million and [removed: $333.1] [added: $293.7] million, respectively.

[removed: Interest Rate Risk][added: INTEREST RATE RISK]

As of December 31, [removed: 2022 and 2021,] [added: 2022,] we estimate that such hypothetical 100 basis point adverse movement would result in a hypothetical loss in fair value of approximately $11.7 million [removed: and $14.3 million, respectively,] to our interest rate sensitive instruments.

[removed: Credit Risk][added: CREDIT RISK]

We operate in certain countries where weakness in economic conditions, including the effects of the [removed: COVID-19 pandemic] [added: conflict between Russia] and [added: Ukraine and] the [added: military] conflict in [removed: Ukraine,] [added: the Middle East,] can result in extended collection periods.

We believe that our allowance for doubtful accounts was adequate as of December 31, [removed: 2022] [added: 2023] and [removed: 2021.][added: 2022.]

As of December 31, [removed: 2022] [added: 2023] and [removed: 2021,] [added: 2022,] a hypothetical adverse 10.0% movement would result in a hypothetical decrease in fair value of approximately [removed: $79.1] [added: $41.7] million and [removed: $104.8] [added: $79.1] million, respectively.

In December 2023 the Argentinian Peso experienced a substantial devaluation following a presidential election.

The devaluation resulted in a $16.0 million charge recorded

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during the fourth quarter of 2023 in other (income) expense, net within our consolidated statements of income for the year ended December 31, 2023.

We partially funded our Reata acquisition through available cash, cash equivalents and marketable securities.

As of December 31, 2023, we have sold all of our marketable debt securities. For additional information on our acquisition of Reata, please read *Note 2, Acquisitions*, to our consolidated financial statements included in this report.

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mitigated by the value of non-U.S. expense, which will also decline when reported in U.S. dollars.

contracts.

We have a broad portfolio of medicines to treat [removed: multiple sclerosis (MS),] [added: MS,] have introduced the first approved treatment for [removed: spinal muscular atrophy (SMA) and] [added: SMA,] co-developed [removed: two] treatments to address a defining pathology of Alzheimer’s [removed: disease.][added: disease and launched the first approved treatment to target a genetic cause of ALS.]

We are focused on advancing our pipeline in neurology, [removed: neuropsychiatry,] specialized immunology and rare diseases.

Our marketed products include TECFIDERA, VUMERITY, AVONEX, PLEGRIDY, TYSABRI and FAMPYRA for the treatment of MS; SPINRAZA for the treatment of SMA; [removed: ADUHELM] [added: SKYCLARYS] for the treatment of [removed: Alzheimer's disease;] [added: Friedreich's Ataxia; QALSODY for the treatment of ALS;] and FUMADERM for the treatment of severe plaque psoriasis.

[removed: We also collaborate with Eisai Co., Ltd. (Eisai) on] [added: In July 2023] the [removed: commercialization] [added: FDA granted traditional approval] of [removed: LEQEMBI] [added: LEQEMBI, an anti-amyloid antibody] for the treatment of Alzheimer's disease, which was [added: previously] granted accelerated approval by the [removed: U.S. Food and Drug Administration (FDA)] [added: FDA] in January 2023.

We [added: also] have [added: collaborations with Eisai on the commercialization of LEQEMBI for the treatment of Alzheimer's disease and Sage on the commercialization of ZURZUVAE for the treatment of PPD and we have] certain business and financial rights with respect to RITUXAN for the treatment of non-Hodgkin's lymphoma, [removed: chronic lymphocytic leukemia (CLL)] [added: CLL] and other conditions; RITUXAN HYCELA for the treatment of non-Hodgkin's lymphoma and CLL; GAZYVA for the treatment of CLL and follicular lymphoma; OCREVUS for the treatment of [removed: primary progressive MS (PPMS)] [added: PPMS] and [removed: relapsing MS (RMS);] [added: RMS;] LUNSUMIO [removed: (mosunetuzumab), which was granted accelerated approval in the U.S. during the fourth quarter of 2022] for the treatment of relapsed or refractory follicular lymphoma; [removed: glofitamab, an investigational] [added: COLUMVI, a] bispecific antibody for the [removed: potential] treatment of non-Hodgkin's lymphoma; and have the option to add other potential anti-CD20 therapies, pursuant to our collaboration arrangements with Genentech, [removed: Inc. (Genentech),] a wholly-owned member of the Roche Group.

We [removed: also] commercialize [added: a portfolio of] biosimilars of advanced biologics including BENEPALI, an etanercept biosimilar referencing ENBREL, IMRALDI, an adalimumab biosimilar referencing HUMIRA, and FLIXABI, an infliximab biosimilar referencing REMICADE, in certain countries in Europe, as well as BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, in the U.S. [removed: We continue to develop potential biosimilar products including BIIB800, a proposed tocilizumab biosimilar referencing ACTEMRA,] and [removed: SB15, a proposed aflibercept biosimilar referencing EYLEA.][added: certain international markets.]

For additional information on our collaboration [removed: arrangements,] [added: with Sage,] please read *Note 19, Collaborative and Other [removed: Relationships*,] [added: Relationships,*] to our consolidated financial statements included in this report.

The following is a summary of key developments affecting our business since the beginning of [removed: 2022.][added: 2023.]

[removed: *Developments in Key Collaborative Relationships*][added: DEVELOPMENTS IN KEY COLLABORATIVE RELATIONSHIPS]

[removed: *LEQEMBI (lecanemab) Collaboration Agreement*][added: LEQEMBI (lecanemab)]

[added: -] In January 2023 the [removed: European Medicines Agency (EMA)] [added: EMA] accepted for review the [removed: Marketing Authorization Application (MAA)] [added: MAA] for lecanemab.

For additional information on our [removed: collaboration arrangements with Eisai,] [added: acquisition of Reata,] please read *Note [removed: 19, Collaborative and Other Relationships,*] [added: 2, Acquisitions*,] to our consolidated financial statements included in this report.

[removed: *Genentech*][added: GENENTECH]

For additional information on our [removed: collaboration arrangements with Genentech,] [added: Fit for Growth program,] please read *Note [removed: 19, Collaborative and Other Relationships*,] [added: 4, Restructuring*,] to our consolidated financial statements included in this report.

[removed: *Other Collaborative Relationships*][added: GENENTECH RELATIONSHIPS IN OTHER INDICATIONS]

[removed: *Corporate Matters*][added: CORPORATE MATTERS]

For additional information on the [removed: sale] [added: discontinuation] of [removed: our equity interest in Samsung Bioepis,] [added: ADUHELM,] please read *Note [removed: 3, Dispositions,*] [added: 20, Investments in Variable Interest Entities*,] to our consolidated financial statements included in this report.

For additional information on [removed: our 2022 cost saving initiatives,] [added: the U.S. patent litigation related to a TYSABRI biosimilar,] please read *Note [removed: 4, Restructuring*,] [added: 21, Litigation*,] to our consolidated financial statements included in this report.

[removed: *Management Changes*][added: MANAGEMENT CHANGES]

[removed: Viehbacher as President and] [added: | Christopher A. Viehbacher | | | | | | President,] Chief Executive [removed: Officer.][added: Officer | | | | | | 63 | | | | | | 2022 | | |]

[removed: - In February 2022 we announced the appointment of Nicole Murphy as] [added: | Nicole Murphy | | | | | |] Executive Vice President, Pharmaceutical Operations and [removed: Technology.][added: Technology | | | | | | 51 | | | | | | 2015 | | |]

- In [removed: January] [added: April] 2023 we announced the appointment of [removed: Priya Singhal] [added: Adam Keeney,] as Executive Vice President, Head of [added: Corporate] Development.

[removed: *Board of Directors Update*][added: BOARD OF DIRECTORS UPDATE]

[removed: Viehbacher] [added: - In June 2023 Susan Langer] joined our Board of Directors.

[removed: Product and Pipeline Developments][added: PRODUCT AND PIPELINE DEVELOPMENTS]

[removed: *Multiple Sclerosis and Neuroimmunology*][added: MULTIPLE SCLEROSIS]

[removed: *Alzheimer's Disease and Dementia*][added: ALZHEIMER'S DISEASE]

[removed: *LEQEMBI (lecanemab)*][added: LEQEMBI (lecanemab)]

- In [removed: September 2022] [added: July 2023] we and Eisai announced [removed: positive topline] [added: the] results [removed: from] [added: of a detailed analysis of] the [removed: confirmatory] Phase 3 CLARITY Alzheimer's disease study of [removed: LEQEMBI.][added: LEQEMBI at the 2023 AAIC conference.]

[removed: *Neuropsychiatry*][added: NEUROPSYCHIATRY]

[removed: *SPINRAZA (nusinersen)*][added: SPINRAZA (nusinersen)]

[removed: *BIIB122 (DNL151)*][added: BIIB122]

[removed: *Biosimilars*][added: BIOSIMILARS]

[removed: *BYOOVIZ] [added: BYOOVIZ] (referencing [removed: LUCENTIS)*][added: LUCENTIS)]

- In [removed: June 2022] [added: March 2023] we [removed: and Samsung Bioepis] announced that BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, launched in [removed: the U.S.][added: Canada.]

[removed: *BIIB800] [added: TOFIDENCE] (referencing [removed: ACTEMRA)*][added: ACTEMRA)]

[removed: *Discontinued Programs*][added: DISCONTINUED PROGRAMS AND STUDIES]

[removed: Marketed Products][added: MARKETED PRODUCTS]

The following graph shows our [removed: revenue by] product [added: revenue] and revenue from anti-CD20 therapeutic programs for the years ended December 31, [removed: 2022, 2021] [added: 2023, 2022] and [removed: 2020.][added: 2021.]

[removed: ][added: ]

Through our 2023 acquisition of Reata we market the first and only drug approved in the U.S. and the E.U. for the treatment of Friedreich's Ataxia in adults and adolescents aged 16 years and older.

We also have exclusive rights to commercialize TOFIDENCE, a tocilizumab biosimilar referencing ACTEMRA.

We continue to develop potential biosimilar product SB15, a proposed aflibercept biosimilar referencing EYLEA.

In February 2023 we announced that we are exploring strategic options for our biosimilars business.

*United States*

Following the FDA's traditional approval of LEQEMBI, CMS confirmed broader coverage of LEQEMBI.

Additionally, in March 2023 Eisai announced that the U.S. Veteran's Health Administration will be providing coverage of LEQEMBI to veterans living with early stages of Alzheimer's disease.

*Rest of World*

Key developments related to LEQEMBI (lecanemab) in rest of world markets during 2023 consisted of the following:

- In January 2024 we and Eisai announced that the SAG will convene at the request of the CHMP to discuss the MAA of lecanemab that is currently under review by the EMA.

The meeting of the SAG is expected to take place during the first quarter of 2024 and the EC decision for the MAA of lecanemab is expected during the first half of 2024.

- In January 2024 the NMPA approved LEQEMBI in China, with an expected launch date in 2024.

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- In December 2023 we and Eisai announced that LEQEMBI intravenous infusion was launched in Japan.

- In September 2023 the Japanese Ministry of Health, Labor and Welfare approved LEQEMBI in Japan.

- In February 2023 the BLA for lecanemab was granted Priority Review by the NMPA of China.

- In May 2023 we and Eisai announced the submission of a MAA for lecanemab to the U.K. MHRA in Great Britain, which has been designated by the MHRA for the Innovative Licensing and Access Pathway.

Additionally, in May 2023 Health Canada accepted for review the NDS for lecanemab.

- In June 2023 we and Eisai announced the submission of a MAA for lecanemab to the Ministry of Food and Drug Safety in South Korea.

ZURZUVAE (zuranolone)

In August 2023 the FDA approved ZURZUVAE for adults with PPD, pending DEA scheduling, which was completed in October 2023.

Upon approval, ZURZUVAE for PPD became the first and only oral, once-daily, 14-day treatment that can provide rapid improvements in depressive symptoms by day 15 for women with PPD.

ZURZUVAE for PPD became commercially available in the U.S. during the fourth quarter of 2023.

Additionally, the FDA issued a CRL for the NDA for zuranolone in the treatment of adults with MDD.

The CRL stated that the application did not provide substantial evidence of effectiveness to support the approval of zuranolone for the treatment of MDD and that an additional study or studies would be needed.

We and Sage are continuing to seek feedback from the FDA and evaluating next steps.

BUSINESS COMBINATIONS

REATA ACQUISITION

On September 26, 2023, we completed the acquisition of all of the issued and outstanding shares of Reata, a biopharmaceutical company focused on developing therapeutics that regulate cellular metabolism and inflammation in serious neurologic diseases.

As a result of this transaction we acquired SKYCLARYS (omaveloxolone), the first and only drug approved in the U.S. and the E.U. for the treatment of Friedreich's Ataxia in adults and adolescents aged 16 years and older, as well as other clinical and preclinical pipeline programs.

Under the terms of this acquisition, we paid Reata shareholders $172.50 in cash for each issued and outstanding Reata share, which totaled approximately $6.6 billion.

In addition, we agreed to pay approximately $983.9 million in cash for Reata's outstanding equity awards, inclusive of employer taxes, of which approximately $590.5 million was attributable to pre-acquisition services and is therefore reflected as a component of total purchase price paid.

Of the $983.9 million paid to Reata's equity award holders, we recognized approximately $393.4 million as compensation attributable to the post-acquisition service period, of which $196.4 million was recognized as a charge to selling, general and administrative expense with the remaining $197.0 million as a charge to research and development expense within our consolidated statements of income for the year ended December 31, 2023.

These amounts were associated with the accelerated vesting of stock options and RSUs previously granted to Reata employees that required no future services to vest.

OTHER KEY DEVELOPMENTS

QALSODY (tofersen)

In April 2023 the FDA approved QALSODY for the treatment of ALS in adults who have a mutation in the SOD1 gene.

This indication is approved under accelerated approval based on reduction in plasma neurofilament light chain observed in patients treated with QALSODY.

Continued approval for this indication may be contingent upon verification of clinical benefit in confirmatory trial(s).

TECFIDERA

In addition to continuing to invest in new potential innovation in MS and SMA we are advancing our mid-to-late stage programs including zuranolone for major depressive disorder (MDD) and postpartum depression (PPD), BIIB080 for Alzheimer's disease, tofersen for amyotrophic lateral sclerosis (ALS) and both litifilimab and dapirolizumab pegol for certain forms of lupus.

*Eisai Collaboration Agreements*

In January 2023 we and Eisai announced that the FDA granted accelerated approval of LEQEMBI, an anti-amyloid antibody for the treatment of Alzheimer's disease.

Additionally, in January 2023 we and Eisai announced the completed submission of a supplemental Biologics License Application (BLA) to the FDA for traditional approval of LEQEMBI.

In January 2023 Eisai completed the submission of a MAA to the Pharmaceuticals and Medical Devices Agency (PMDA) in Japan for lecanemab, and was granted Priority Review by the Japanese Ministry of Health, Labor and Welfare.

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In December 2022 Eisai initiated a rolling submission of a BLA to the National Medicinal Products Administration (NMPA) of China for the approval of lecanemab.

In March 2022 we extended our supply agreement with Eisai related to LEQEMBI from five years to ten years for the manufacture of LEQEMBI drug substance.

*ADUHELM Collaboration Agreement*

On March 14, 2022, we amended our ADUHELM Collaboration Agreement with Eisai.

As of the amendment date, we have sole decision making and commercialization rights worldwide on ADUHELM, and beginning January 1, 2023, Eisai receives only a tiered royalty based on net sales of ADUHELM, and no longer participates in sharing ADUHELM's global profits and losses.

Eisai's share of development, commercialization and manufacturing expense was limited to $335.0 million for the period from January 1, 2022 to December 31, 2022, which was achieved as of December 31, 2022.

Once this limit was achieved, we became responsible for all ADUHELM related costs.

*Zuranolone (BIIB125)*

In June 2022 we and our collaboration partner Sage Therapeutics, Inc. (Sage) announced that the Phase 3 SKYLARK study of zuranolone, for the potential treatment of MDD and PPD, met its primary and all key secondary endpoints.

In December 2022 we and Sage completed the rolling submission of a New Drug Application (NDA) to the FDA for the approval of zuranolone for the potential treatment of MDD and PPD.

This submission completes the NDA filing initiated earlier in 2022.

In February 2023 the FDA accepted the NDA and granted Priority Review for zuranolone, with a Prescription Drug User Fee Act (PDUFA) action date of August 5, 2023.

*LUNSUMIO (mosunetuzumab)*

In January 2022 we exercised our option with Genentech to participate in the joint development and commercialization of LUNSUMIO (mosunetuzumab), a bispecific antibody for the treatment of relapsed or refractory follicular lymphoma.

In connection with this exercise, we recorded a $30.0 million option exercise fee payable to Genentech in December 2021.

In December 2022 Genentech announced that the FDA granted accelerated approval of LUNSUMIO, which was also approved by the European Commission (EC) in June 2022.

*Glofitamab*

In December 2022 we reached an agreement with Genentech related to the commercialization and sharing of economics for glofitamab, an investigational T-cell engaging bispecific antibody targeting CD20 and CD3 for the potential treatment of B-cell non-Hodgkin's lymphoma.

*Alcyone Therapeutics*

In December 2022 we entered into a license and collaboration agreement with Alcyone Therapeutics (Alcyone) to jointly develop the ThecaFlex DRx™ System, an implantable medical device intended for subcutaneous delivery of antisense oligonucleotide (ASO) therapies with a goal of improving the patient treatment experience and accessibility for people suffering from neurological disorders, such as SMA and ALS.

Under the terms of this collaboration, we and Alcyone will jointly develop the ThecaFlex DRx™ System and Alcyone will be solely responsible for its manufacture and commercialization.

In connection with this transaction, we made an upfront payment of $10.0 million to Alcyone.

*Samsung Bioepis - Biogen's Joint Venture with Samsung BioLogics*

In April 2022 we completed the sale of our 49.9% equity interest in Samsung Bioepis to Samsung BioLogics Co., Ltd. (Samsung BioLogics).

Under the terms of this transaction, we received approximately $1.0 billion in cash at closing and expect to receive approximately $1.3 billion in cash to be deferred over two payments of approximately $812.5 million due at the first anniversary and approximately $437.5 million due at the second anniversary of the closing of this transaction.

As part of this transaction, we are also eligible to receive up to an additional $50.0 million upon the achievement of certain commercial milestones.

Our policy for contingent payments of this nature is to recognize the payments in the period that they become realizable, which is generally the same period in which the payments are earned.

*2022 Cost Saving Initiatives*

In December 2021 and May 2022 we announced our plans to implement a series of cost-reduction measures that when completed we expect may yield approximately $1.0 billion in expense savings.

These savings are being achieved through a number of initiatives, including reductions to our workforce, the substantial elimination of our commercial ADUHELM infrastructure, the consolidation of certain real estate locations and operating efficiency gains across our selling, general and administrative and research and development functions.

Under these initiatives, we estimate we will incur total restructuring charges of approximately $131.0 million, primarily related to severance.

These amounts were substantially incurred during 2022.

As of December 31, 2022, approximately $35.9 million remained in our restructuring reserve and payments are expected to be made through 2026.

*125 Broadway Sale and Leaseback Transaction*

For a discussion of legal matters as of December 31, [removed: 2022,] [added: 2023,] please read *Note 21, Litigation,* to our consolidated financial statements included in this report, which is incorporated into this item by reference.

For the fiscal year ended December 31, [removed: 2022][added: 2023]

[removed: ][added: ]

The aggregate market value of the registrant’s common stock held by non-affiliates of the registrant (without admitting that any person whose shares are not included in such calculation is an affiliate) computed by reference to the price at which the common stock was last sold as of the last business day of the registrant’s most recently completed second fiscal quarter was [removed: $29,397,964,818.][added: $41,190,868,800.]

As of February [removed: 14, 2023,] [added: 12, 2024,] the registrant had [removed: 144,485,646] [added: 145,360,798] shares of common stock, $0.0005 par value, outstanding.

Portions of the definitive proxy statement for our [removed: 2023] [added: 2024] Annual Meeting of Stockholders are incorporated by reference into Part III of this report.

For the Year Ended December 31, [removed: 2022][added: 2023]

| [Item [removed: 1.](#i0cbadda4abfc4b4b9c7e5be15680d793_22)] [added: 1.](#ie5989ff7709d49d194ee19ecbcc140c3_25)] | | | [removed: [Business](#i0cbadda4abfc4b4b9c7e5be15680d793_22)] [added: [Business](#ie5989ff7709d49d194ee19ecbcc140c3_25)] | | | [removed: [1](#i0cbadda4abfc4b4b9c7e5be15680d793_22)] [added: [1](#ie5989ff7709d49d194ee19ecbcc140c3_25)] | | |

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These forward-looking statements may be accompanied by such words as “aim,” “anticipate,” “believe,” “could,” [added: "contemplate," "continue,"] “estimate,” “expect,” “forecast,” "goal," “intend,” “may,” “plan,” “potential,” “possible,” [added: "predict," "project", "should," "target,"] “will,” “would” [removed: and] [added: or the negative of these words or] other words and terms of similar meaning.

- expectations, plans and prospects relating to [added: product approvals,] sales, pricing, growth, reimbursement and launch of our marketed and pipeline products;

- patent terms, patent term extensions, patent office actions and expected availability and [removed: period] [added: periods] of regulatory exclusivity;

- the drivers for growing our business, including our plans and intention to commit resources relating to discovery, research and development programs and business development opportunities as well as the potential benefits and results of, and the anticipated completion of, certain business development transactions and cost-reduction [removed: measures;][added: measures, including our Fit for Growth program;]

- the expectations, development plans and anticipated timelines, including costs and timing of potential clinical trials, [added: regulatory] filings and approvals, of our products, drug candidates and pipeline programs, including collaborations with third-parties, as well as the potential therapeutic scope of the development and commercialization of our and our collaborators’ pipeline products;

- the timing, outcome and impact of administrative, regulatory, legal and other proceedings related to our patents and other proprietary and intellectual property rights, tax audits, assessments and settlements, pricing matters, sales and promotional practices, product [removed: liability] [added: liability, investigations] and other matters;

- adverse safety events involving our marketed [added: or pipeline] products, generic or biosimilar versions of our marketed products or any other products from the same class as one of our products;

- the direct and indirect impact of [removed: the COVID-19 pandemic and other] global health outbreaks on our business and operations, including sales, expense, reserves and allowances, the supply chain, manufacturing, [removed: cyber-attacks or other privacy or data security incidents,] research and development costs, clinical trials and employees;

- the current and potential impacts of [removed: the conflict in Ukraine,] [added: geopolitical tensions, acts of war and other large-scale crises,] including impacts [removed: on] [added: to] our operations, sales and the possible disruptions or [removed: delays] [added: delay] in our plans to conduct clinical trial activities in [added: areas of geopolitical tension, including regions] affected [removed: regions;][added: by Russia's invasion of Ukraine and the military conflict in the Middle East;]

- the potential impact of healthcare reform in the [removed: United States (U.S.),] [added: U.S.,] including the [removed: Inflation Reduction Act of 2022 (IRA),] [added: IRA,] and measures being taken worldwide designed to reduce healthcare costs and limit the overall level of government expenditures, including the impact of pricing actions and reduced reimbursement for our products;

- our manufacturing capacity, use of third-party contract manufacturing organizations, plans and timing relating to changes in our manufacturing capabilities, activities in new or existing manufacturing facilities and the expected timeline for the [removed: remaining portion of the Solothurn manufacturing facility to begin manufacturing products or product candidates and for the] gene therapy manufacturing facility in [removed: Research Triangle Park (RTP), NC] [added: RTP, North Carolina] to be operational;

If securities are registered pursuant to Section 12(b) of the Act, indicate by check mark whether the financial statements of the registrant included in the filing reflect the correction of an error to previously issued financial statements.

Indicate by check mark whether any of those error corrections are restatements that required a recovery analysis of incentive-based compensation received by any of the registrant's executive officers during the relevant recovery period pursuant to §240.10D-1(b).

| [PART I](#ie5989ff7709d49d194ee19ecbcc140c3_22) | | | | | | | | |

| [Item 1C.](#ie5989ff7709d49d194ee19ecbcc140c3_3122) | | | [Cybersecurity](#ie5989ff7709d49d194ee19ecbcc140c3_3122) | | | [54](#ie5989ff7709d49d194ee19ecbcc140c3_3122) | | |

| [PART II](#ie5989ff7709d49d194ee19ecbcc140c3_85) | | | | | | | | |

| [PART III](#ie5989ff7709d49d194ee19ecbcc140c3_205) | | | | | | | | |

| [PART IV](#ie5989ff7709d49d194ee19ecbcc140c3_223) | | | | | | | | |

| [Signatures](#ie5989ff7709d49d194ee19ecbcc140c3_235) | | | | | | [100](#ie5989ff7709d49d194ee19ecbcc140c3_235) | | |

[T](#ie5989ff7709d49d194ee19ecbcc140c3_10)[able of Contents](#ie5989ff7709d49d194ee19ecbcc140c3_10)

- the execution of our strategic and growth initiatives, including the ultimate success of our acquisition of Reata and our ability to realize the anticipated benefits from the acquisition, including future performance of the SKYCLARYS product and anticipated synergies, as well as the exploration of strategic options for our biosimilars business;

- our use of information systems and data and the potential impacts of any breakdowns, invasions, corruptions, destructions and/or breaches of such systems or those of our business partners;

[T](#ie5989ff7709d49d194ee19ecbcc140c3_10)[able of Contents](#ie5989ff7709d49d194ee19ecbcc140c3_10)

Because some of these risks and uncertainties cannot be predicted or quantified and some are beyond our control, you should not rely on our forward-looking statements as predictions of future events and you should not place undue reliance on these statements.

Moreover, we operate in a very competitive and rapidly changing environment, new risks and uncertainties may emerge from time to time and it is not possible for us to predict all risks nor identify all uncertainties.

You should read this report with the understanding that our actual future results, performance, events and circumstances might be materially different from what we expect.

[T](#ie5989ff7709d49d194ee19ecbcc140c3_10)[able of Contents](#ie5989ff7709d49d194ee19ecbcc140c3_10)

DEFINED TERMS

| | | | | | |

| --- | --- | --- | --- | --- | --- |

| 2022 Form 10-K | | | Annual Report on Form 10-K for the year ended December 31, 2022 | | |

| 2020 Share Repurchase Program | | | Board of Directors authorized program to repurchase up to $5.0 billion of our common stock | | |

| 125 Broadway | | | 125 Broadway, Cambridge, MA | | |

| 300 Binney Street | | | 300 Binney Street, Cambridge, MA | | |

| AAIC | | | Alzheimer's Association International Conference | | |

| AbbVie | | | AbbVie Inc. | | |

| Acorda | | | Acorda Therapeutics, Inc. | | |

| AI | | | Artificial Intelligence | | |

| Alkermes | | | Alkermes plc | | |

| ALS | | | Amyotrophic Lateral Sclerosis | | |

| AMP | | | Average Manufacturer Price | | |

| AOCI | | | Accumulated Other Comprehensive Income (Loss) | | |

| ASO | | | Antisense Oligonucleotide | | |

| ASU | | | Accounting Standards Update | | |

| ATV | | | Antibody Transport Vehicle | | |

| BLA | | | Biologics License Application | | |

| Blackstone | | | Blackstone Life Sciences | | |

| CCDAA | | | Climate Corporate Data Accountability Act | | |

| CCPA | | | California Consumer Privacy Act | | |

| CEO | | | Chief Executive Officer | | |

| CHMP | | | Committee for Medicinal Products for Human Use | | |

| [PART I](#i0cbadda4abfc4b4b9c7e5be15680d793_19) | | | | | | | | |

| [PART II](#i0cbadda4abfc4b4b9c7e5be15680d793_82) | | | | | | | | |

| [PART III](#i0cbadda4abfc4b4b9c7e5be15680d793_190) | | | | | | | | |

| [PART IV](#i0cbadda4abfc4b4b9c7e5be15680d793_208) | | | | | | | | |

| [Signatures](#i0cbadda4abfc4b4b9c7e5be15680d793_220) | | | | | | [88](#i0cbadda4abfc4b4b9c7e5be15680d793_220) | | |

[Table of](#i0cbadda4abfc4b4b9c7e5be15680d793_7) [Conten](#i0cbadda4abfc4b4b9c7e5be15680d793_7)[ts](#i0cbadda4abfc4b4b9c7e5be15680d793_7)

You should not place undue reliance on these statements.

RISK MANAGEMENT AND STRATEGY

We maintain a technology and cybersecurity program, which includes information security, as part of our overall risk management process with the aim that our information systems, including those of our vendors and other third-parties, will be resilient, effective and capable of safeguarding against emerging risks and cybersecurity threats.

We endeavor to assure our program is appropriately resourced and to attract and retain expert talent to execute it.

In designing, operating, evaluating and maintaining our program we use internal and external resources and frameworks, including cybersecurity expert consultants, industry working groups, the U.S. NIST Cybersecurity Framework and the U.S. Cybersecurity Agency's National Cyber Incident Scoring System model to benchmark, inform and evaluate the design of our program, our operational capabilities and our program maturity.

Consistent with NIST 800-53, our technology and cybersecurity program and controls include a third party and vendor risk management component.

As part of our vendor risk management program, we conduct security assessments prior to engagement of high-risk vendors and other third-party providers and have a monitoring program to evaluate ongoing compliance with our cybersecurity standards.

[T](#ie5989ff7709d49d194ee19ecbcc140c3_10)[able of Contents](#ie5989ff7709d49d194ee19ecbcc140c3_10)

A key element of our technology and cybersecurity program strategy is fostering training and awareness.

Our training and awareness program includes annual cybersecurity awareness training and role-based phishing tests for our employees and for third parties with access to our systems.

Our technology and cybersecurity program focuses on the defense, rapid detection and rapid remediation of cybersecurity threats and incidents.

Our program includes systems and processes designed based on defense-in-depth and zero-trust architectural principles and that are intended to provide the control capabilities set forth in NIST's 800-53 Rev 5, Security and Privacy Controls for Information Systems and Organizations.

Our program also includes cybersecurity policies and a crisis response and management plan that is intended to allow rapid management and response and appropriate communication of cybersecurity threats and incidents.

We staff a cybersecurity operations center to respond to threats and incidents.

Our cybersecurity crisis management plan sets forth the items, procedures and actions we expect to address and follow in the event of a cybersecurity incident, including detection, response, mitigation and remediation.

In addition to the cybersecurity operations center and our designated cybersecurity response team, we maintain a cross-functional cybersecurity crisis core team, which includes our CISO and senior representatives from our Legal, Finance, IT and Corporate Security teams.

When a potential threat or incident is identified, our cyber security incident response team will assign a risk level classification and initiate the escalation and other steps called for by our plan.

All incidents that are initially assessed by the cybersecurity incident response team as potentially high-risk are escalated promptly to our CISO.

Our CISO, Chief Legal Officer and Chief Financial Officer, will determine whether and what elements of our cybersecurity crisis response and management plan should be activated, including escalation to other senior management or our Executive Committee.

Our Executive Committee will inform our Board of Directors of cybersecurity incidents, as appropriate, considering a variety of factors, including financial, operational, legal or reputational impact.

Our program's maturity and operational readiness are regularly evaluated by independent experts using the U.S. NIST's CyberSecurity Framework and penetration tests.

Our program, and the results of these independent evaluations and testing, are regularly reviewed by our senior management and members of our Board of Directors.

CYBERSECURITY RISK GOVERNANCE

We are committed to appropriate cybersecurity governance and oversight.

Our technology and cybersecurity program is the principal responsibility of our Chief Information Officer and CISO, each of whom have over 20 years of experience in information systems, including cybersecurity training and experience.

Additionally, we have a Cybersecurity steering committee that includes senior representatives from our Legal, Finance and IT departments, which meets regularly to discuss cybersecurity matters.

Our Board of Directors oversees management's processes for identifying and mitigating risks, including cybersecurity and information security risks.

Our Audit Committee of our Board of Directors regularly reviews our technology and cybersecurity program and effectiveness, internal audits of our program, independent external expert evaluations of our program's maturity and operational readiness and the results of penetration testing.

Our Audit Committee also receives regular cybersecurity updates and education on a broad range of topics, including:

- Current cybersecurity landscape and emerging threats;

- Status of ongoing cybersecurity initiatives and strategies;

- Incident report and learnings from any cybersecurity events; and

- Compliance with regulatory requirements and industry standards.

For additional information on our cybersecurity risks, please read *Item 1A.

Risk Factors - A breakdown or breach of our technology systems could subject us to liability or interrupt the operation of our business*, included in this report.

Below is a summary of our owned and leased properties as of December 31, [removed: 2022.][added: 2023.]

[removed: U.S.][added: U.S.]

[removed: *Massachusetts*][added: MASSACHUSETTS]

In Cambridge, [removed: MA] [added: Massachusetts] we own approximately 263,000 square feet of real estate space, consisting of a building that houses a research laboratory and a cogeneration plant.

In addition, we lease a total of approximately [removed: 1,429,000] [added: 1,165,000] square feet in Massachusetts, which is summarized as follows:

- [removed: 1,072,000] [added: 808,000] square feet in Cambridge, [removed: MA,] [added: Massachusetts,] which is comprised of offices for our corporate headquarters and other administrative and development functions and laboratories, of which [removed: 289,000] [added: 209,000] square feet is subleased by multiple companies for general office space, laboratories and manufacturing facilities; and

- 357,000 square feet of office space in Weston, [removed: MA,] [added: Massachusetts,] of which 174,000 square feet is subleased through the remaining term of our lease agreement.

[removed: *125 Broadway Building Sale and Leaseback*][added: 125 BROADWAY BUILDING SALE AND LEASEBACK]

[added: For additional information] on our 125 Broadway sale and leaseback transaction, please read *Note 11, Property, Plant and [removed: Equipment] [added: Equipment*] and [removed: Note] [added: *Note] 12, Leases*, to our consolidated financial statements included in this report.

[removed: *300 Binney Street Lease Modification*][added: 300 BINNEY STREET LEASE MODIFICATION]

In September 2022 we entered into an agreement to partially terminate a portion of our lease located at 300 Binney Street, [removed: Cambridge, MA (300 Binney Street),] as well as to reduce the lease term for the majority of the remaining space.

[removed: *North Carolina*][added: NORTH CAROLINA]

In RTP, [removed: NC] [added: North Carolina] we own approximately 1,040,000 square feet of real estate space, which is summarized as follows:

In addition, we lease approximately 65,000 square feet of warehouse space in Durham, [removed: NC.][added: North Carolina.]

In [removed: March] [added: the fourth quarter of] 2021 we [removed: announced our plans to build] [added: began construction of] a new gene therapy manufacturing facility in RTP, [removed: NC] [added: North Carolina] to support our gene therapy pipeline across multiple therapeutic areas.

The new manufacturing facility will be approximately 197,000 square [removed: feet and is expected to be operational by the end of 2023, with an estimated total investment of approximately $195.0 million.][added: feet.]

[removed: International][added: INTERNATIONAL]

[removed: *Switzerland*][added: SWITZERLAND]

In order to support our future growth and drug development pipeline, we [removed: are building] [added: built] a large-scale biologics manufacturing facility in Solothurn, Switzerland.

[removed: Upon completion, this] [added: This] facility [removed: will include] [added: includes] 393,000 square feet related to a large-scale biologics manufacturing facility, 290,000 square feet of warehouse, utilities and support space and 51,000 square feet of administrative space.

In the second quarter of 2021 a portion of the facility [added: (the first manufacturing suite)] received a GMP multi-product license from [removed: SWISSMEDIC.][added: the SWISSMEDIC and was placed into service.]

[removed: Other International][added: OTHER INTERNATIONAL]

Our international lease agreements expire at various dates through the year [removed: 2031.][added: 2034.]

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Our lease expires in May 2025 and we do not intend on renewing the lease agreement.

In connection with this sale, we simultaneously leased back the building for a term of approximately 5.5 years.

As we continue to advance our research and development prioritization efforts, which includes refocusing our investment in gene therapy, we are evaluating several alternative uses for this facility.

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TEXAS

As part of our acquisition of Reata in September 2023 we acquired leases totaling approximately 404,000 square feet of real estate space, which is summarized as follows:

- 327,000 square feet in Plano, Texas, which is comprised of office and laboratory space, with an initial lease term through the year 2038.

We do not intend to occupy this building and are evaluating opportunities to sublease this property;

- 35,000 square feet in Irving, Texas, which is comprised of office and laboratory space and expires in 2024; and

- 42,000 square feet in Plano, Texas, which is comprised of office and laboratory space and expires in 2024.

For additional information on our acquisition of Reata, please read *Note 2, Acquisitions*, to our consolidated financial statements included in this report.

The second manufacturing suite became operational in January 2024.

For additional information on our Solothurn manufacturing facility, please read *Note 11, Property, Plant and Equipment,* to our consolidated financial statements included in this report.

In connection with this sale, we simultaneously leased back the building for a term of approximately 5.5 years, which resulted in the recognition of approximately $168.2 million in new lease liabilities and right-of-use assets recorded within our consolidated balance sheets as of December 31, 2022.

For additional information

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Construction for this new facility began during the fourth quarter of 2021.

We estimate the second manufacturing suite at the Solothurn facility will be operational by the end of 2023.

[removed: PART II][added: PART II]

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Our common stock trades on The Nasdaq Global Select Market under the symbol “BIIB.” As of February [removed: 14, 2023,] [added: 12, 2024,] there were approximately [removed: 448] [added: 420] shareholders of record of our common stock.

The following table summarizes our common stock repurchase activity during the fourth quarter of [removed: 2022:][added: 2023:]

| October [removed: 2022] [added: 2023] | | | — | | | | | | $ | — | | | | | — | | | | | | $ | 2,050.0 | |

| November [removed: 2022] [added: 2023] | | | — | | | | | | $ | — | | | | | — | | | | | | $ | 2,050.0 | |

| December [removed: 2022] [added: 2023] | | | — | | | | | | $ | — | | | | | — | | | | | | $ | 2,050.0 | |

(1) There were no share repurchases during the fourth quarter of [removed: 2022.][added: 2023.]

In October 2020 our Board of Directors authorized [added: our 2020 Share Repurchase Program, which is] a program to repurchase up to $5.0 billion of our common [removed: stock (2020 Share Repurchase Program).][added: stock.]

Under our 2020 Share Repurchase Program, we repurchased and retired approximately 3.6 [removed: million, 6.0] million and [removed: 1.6] [added: 6.0] million shares of our common stock at a cost of approximately $750.0 [removed: million,] [added: million and] $1.8 billion [removed: and $400.0 million] during the years ended December 31, [removed: 2022, 2021] [added: 2022] and [removed: 2020,] [added: 2021,] respectively.

Approximately $2.1 billion remained available under our 2020 Share Repurchase Program as of December 31, [removed: 2022.][added: 2023.]

[removed: Performance Graph][added: PERFORMANCE GRAPH]

The performance graph below assumes the investment of $100.00 on December 31, [removed: 2017,] [added: 2018,] in our common stock and each of the three indexes, with dividends being reinvested.

[removed: ][added: ]

| | | | | | | [removed: 2017] [added: 2018] | | | | | | [removed: 2018] [added: 2019] | | | | | | [removed: 2019] [added: 2020] | | | | | | [removed: 2020] [added: 2021] | | | | | | [removed: 2021] [added: 2022] | | | | | | [removed: 2022] [added: 2023] | | |

There were no share repurchases of our common stock during the year ended December 31, 2023.

While we have historically made discretionary share repurchases, we had no share repurchases of our common stock during the year ended December 31, 2023.

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| Biogen Inc. | | | | | | $100.00 | | | | | | $98.61 | | | | | | $81.37 | | | | | | $79.73 | | | | | | $92.01 | | | | | | $85.97 | | |

| Nasdaq Pharmaceutical Index | | | | | | $100.00 | | | | | | $114.51 | | | | | | $126.56 | | | | | | $157.42 | | | | | | $175.29 | | | | | | $182.08 | | |

| S&P 500 Index | | | | | | $100.00 | | | | | | $131.49 | | | | | | $155.68 | | | | | | $200.37 | | | | | | $164.08 | | | | | | $207.21 | | |

| Nasdaq Biotechnology Index | | | | | | $100.00 | | | | | | $125.11 | | | | | | $158.17 | | | | | | $158.20 | | | | | | $142.19 | | | | | | $148.72 | | |

In December 2019 our Board of Directors authorized a program to repurchase up to $5.0 billion of our common stock (December 2019 Share Repurchase Program), which was completed as of September 30, 2020.

All shares repurchased under our December 2019 Share Repurchase Program were retired.

Under our December 2019 Share Repurchase Program, we repurchased and retired approximately 16.7 million shares of our common stock at a cost of approximately $5.0 billion during the year ended December 31, 2020.

In March 2019 our Board of Directors authorized a program to repurchase up to $5.0 billion of our common stock (March 2019 Share Repurchase Program), which was completed as of March 31, 2020.

All shares repurchased under our March 2019 Share Repurchase Program were retired.

Under our March 2019 Share Repurchase Program, we repurchased and retired approximately 4.1 million shares of our common stock at a cost of approximately $1.3 billion during the year ended December 31, 2020.

Historically, we have made discretionary share repurchases.

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| Biogen Inc. | | | | | | $100.00 | | | | | | $94.46 | | | | | | $93.14 | | | | | | $76.86 | | | | | | $75.31 | | | | | | $86.92 | | |

| Nasdaq Pharmaceutical Index | | | | | | $100.00 | | | | | | $107.95 | | | | | | $123.62 | | | | | | $136.62 | | | | | | $169.94 | | | | | | $189.23 | | |

| S&P 500 Index | | | | | | $100.00 | | | | | | $95.62 | | | | | | $125.72 | | | | | | $148.85 | | | | | | $191.58 | | | | | | $156.88 | | |

| Nasdaq Biotechnology Index | | | | | | $100.00 | | | | | | $91.14 | | | | | | $114.02 | | | | | | $144.15 | | | | | | $144.18 | | | | | | $129.59 | | |

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The information required by this Item 8 is contained on pages F-1 through [removed: F-79] [added: F-85] of this report and is incorporated herein by reference.

[removed: Disclosure Controls and Procedures and Internal Control over Financial Reporting][added: DISCLOSURE CONTROLS AND PROCEDURES AND INTERNAL CONTROL OVER FINANCIAL REPORTING]

[removed: Controls and Procedures][added: CONTROLS AND PROCEDURES]

We have carried out an evaluation, under the supervision and with the participation of our management, including our principal executive officer and principal financial officer, of the effectiveness of [added: the design and operation of our disclosure controls and procedures (as defined in Rules 13a-15(e) or 15d-15(e) under the Securities Exchange Act of 1934, as amended), as of December 31, 2023.]

[removed: Changes in Internal Control over Financial Reporting][added: CHANGES IN INTERNAL CONTROL OVER FINANCIAL REPORTING]

There were no changes in our internal control over financial reporting during the quarter ended December 31, [removed: 2022,] [added: 2023,] that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

[removed: Management’s Annual Report on Internal Control over Financial Reporting][added: MANAGEMENT'S ANNUAL REPORT ON INTERNAL CONTROL OVER FINANCIAL REPORTING]

Our management assessed the effectiveness of our internal control over financial reporting as of December 31, [removed: 2022.][added: 2023.]

Based on our assessment, our management has concluded that, as of December 31, [removed: 2022,] [added: 2023,] our internal control over financial reporting is effective based on those criteria.

The effectiveness of our internal control over financial reporting as of December 31, [removed: 2022,] [added: 2023,] has been audited by PricewaterhouseCoopers LLP, an independent registered public accounting firm, as stated in their attestation report, which is included herein.

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We excluded Reata from our assessment of internal control over financial reporting as of December 31, 2023, as Reata was acquired by our Company in a business combination during 2023.

The total assets and total revenue of Reata represents 1.0% and 0.6%, respectively, of the related consolidated financial statement amounts as of and for the year ended December 31, 2023.

the design and operation of our disclosure controls and procedures (as defined in Rules 13a-15(e) or 15d-15(e) under the Securities Exchange Act of 1934, as amended), as of December 31, 2022.

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RULE 10b5-1 TRADING ARRANGEMENTS

From time to time, our officers (as defined in Rule 16a-1(f)) and directors may enter into Rule 10b5-1 or non-Rule 10b5-1 trading arrangements (as each such term is defined in Item 408 of Regulation S-K).

During the fourth quarter of 2023 our officers and directors took the following actions with respect to 10b5-1 trading arrangements:

| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |

| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |

| | | | | | | | | | | | | | | | | | | Trading Arrangement | | | | | | | | | | | | | | | | | | | | |

| Name and Position | | | | | | Action | | | | | | Date | | | | | | Rule 10b5-1 | | | | | | Non-Rule 10b5-1 | | | | | | Total Shares to be Sold | | | | | | Expiration Date | | |

| Robin Kramer (Senior Vice President, Chief Accounting Officer) | | | | | | Adopt | | | | | | 11/13/2023 | | | | | | X | | | | | | — | | | | | | 1,500 | | | | | | 11/10/2025 | | |

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None.

[removed: PART III][added: PART III]

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The response to the remainder of this item is incorporated by reference from the discussion responsive thereto in the sections entitled “*Proposal 1 - Election of Directors,” “Corporate [removed: Governance at Biogen”*] [added: Governance”*] and “*Miscellaneous - Stockholder Proposals*” contained in the proxy statement for our [removed: 2023] [added: 2024] annual meeting of stockholders.

The response to this item is incorporated by reference from the discussion responsive thereto in the sections entitled “*Executive Compensation [removed: Matters*”] [added: Tables,*” *"Compensation Discussion] and [added: Analysis"* and] *“Corporate [removed: Governance at Biogen”*] [added: Governance”*] contained in the proxy statement for our [removed: 2023] [added: 2024] annual meeting of stockholders.

The response to this item is incorporated by reference from the discussion responsive thereto in the sections entitled *“Stock Ownership”* and *“Equity Compensation Plan Information”* contained in the proxy statement for our [removed: 2023] [added: 2024] annual meeting of stockholders.

The response to this item is incorporated by reference from the discussion responsive thereto in the sections entitled “*Certain Relationships and Related Person Transactions*” and *“Corporate [removed: Governance at Biogen*”] [added: Governance*”] contained in the proxy statement for our [removed: 2023] [added: 2024] annual meeting of stockholders.

The response to this item is incorporated by reference from the discussion responsive thereto in the section entitled “*Proposal 2 - Ratification of the Selection of our Independent Registered Public Accounting Firm*” contained in the proxy statement for our [removed: 2023] [added: 2024] annual meeting of stockholders.

[removed: PART IV][added: PART IV]

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| Report of Independent Registered Public Accounting Firm (PCAOB ID 238) | | | | | | [removed: F-78] [added: F-83] | | |

The exhibits listed on the Exhibit Index beginning on page [removed: 85,] [added: 98,] which is incorporated herein by reference, are filed or furnished as part of this report or are incorporated into this report by reference.

[removed: EXHIBIT INDEX][added: EXHIBIT INDEX]

| [removed: 2.1†] [added: 2.1] | | | | | | [removed: [Asset Purchase Agreement among Biogen Idec International Holding Ltd., Elan Pharma International Limited] [added: [Agreement] and [removed: Elan] [added: Plan of Merger by and among Reata] Pharmaceuticals, Inc., [added: Biogen Inc. and River Acquisition, Inc.] dated as of [removed: February 5, 2013.] [added: July 28, 2023.] Filed as Exhibit 2.1 to our [removed: Current Report] [added: current report] on Form [removed: 8-K/A] [added: 8-K] filed [removed: on February 12, 2013.](http://www.sec.gov/Archives/edgar/data/875045/000087504513000010/apa.htm)] [added: July 31, 2023.](https://www.sec.gov/Archives/edgar/data/875045/000119312523198542/d454539dex21.htm)] | | |

| [removed: 2.2] [added: 10.29*] | | | | | | [removed: [Separation Agreement] [added: [Employment Agreement, dated November 10, 2022, by and] between Biogen Inc. and [removed: Bioverativ Inc. dated as of January 31, 2017.] [added: Christopher A. Viehbacher.] Filed as Exhibit [removed: 2.1] [added: 10.1] to our Current Report on Form 8-K filed on [removed: February 2, 2017.](http://www.sec.gov/Archives/edgar/data/875045/000087504517000007/ex21_separationxagreement.htm)] [added: November 10, 2022.](https://www.sec.gov/Archives/edgar/data/875045/000119312522281950/d419645dex101.htm)] | | |

| 3.4 | | | | | | [removed: [Fourth] [added: [Fifth] Amended and Restated Bylaws. Filed as Exhibit 3.1 to our Current Report on Form 8-K filed on [removed: June 9, 2017.](http://www.sec.gov/Archives/edgar/data/875045/000119312517200127/d406783dex31.htm)] [added: December 12, 2023.](https://www.sec.gov/Archives/edgar/data/875045/000119312523293433/d850833dex31.htm)] | | |

| [removed: 4.8+] [added: 4.6+] | | | | | | [Description of [removed: Securities.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/biib-20211231xex48.htm)] [added: Securities.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit46-descriptionofsec.htm)] | | |

| [removed: 10.1] [added: 10.3] | | | | | | [Credit [removed: Agreement between] [added: Agreement, dated as of August 28, 2023, among] Biogen Inc., [removed: Bank of America, N.A., Goldman Sachs] [added: JPMorgan Chase] Bank [removed: USA] [added: N.S., as administrative agent] and [added: the] other lenders party [removed: thereto, dated August 28, 2015.] [added: thereto.] Filed as Exhibit 10.1 to our Current Report on Form 8-K filed on September 1, [removed: 2015.](http://www.sec.gov/Archives/edgar/data/875045/000087504515000028/creditagreement2015biogen.htm)] [added: 2023.](https://www.sec.gov/Archives/edgar/data/875045/000119312523227692/d540978dex101.htm)] | | |

| [removed: 10.2] [added: 10.1] | | | | | | [Credit Agreement, dated as of January 28, 2020, among Biogen Inc., Bank of America, N.A., as administrative agent, swing line lender and the L/C issuer, and the other lenders party thereto. Filed as Exhibit 10.1 to our Current Report on Form 8-K filed on February 3, 2020.](https://www.sec.gov/Archives/edgar/data/875045/000119312520022940/d854655dex101.htm) | | |

| [removed: 10.3+] [added: 10.2] | | | | | | [Amendment to Credit Agreement, dated as of February 7, 2023, by and among Biogen Inc., Bank of America, N.A., as administrative agent, swing line lender and the L&C issuer, and the other lenders party [removed: thereto.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit103amendmenttocredi.htm)] [added: thereto. Filed as Exhibit 10.3 to our Annual Report on Form 10-K for the year ended December 31, 2022.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit103amendmenttocredi.htm)] | | |

| [removed: 10.7*] [added: 10.6*] | | | | | | [Biogen Inc. 2017 Omnibus Equity Plan. Filed as Appendix B to our Definitive Proxy Statement on Schedule 14A filed on April 26, 2017.](http://www.sec.gov/Archives/edgar/data/875045/000119312517139450/d43428ddef14a.htm#toc43428_63) | | |

| [removed: 10.8*] [added: 10.7*] | | | | | | [Form of restricted stock unit award agreement under the Biogen Inc. 2017 Omnibus Equity Plan. Filed as Exhibit 10.2 to our Quarterly Report on Form 10-Q for the quarter ended June 30, 2017.](http://www.sec.gov/Archives/edgar/data/875045/000087504517000024/biib-2017630xexhibit102.htm) | | |

| [removed: 10.9*] [added: 10.8*] | | | | | | [Form of market stock unit award agreement under the Biogen Inc. 2017 Omnibus Equity Plan. Filed as Exhibit 10.3 to our Quarterly Report on Form 10-Q for the quarter ended June 30, 2017.](http://www.sec.gov/Archives/edgar/data/875045/000087504517000024/biib-2017630xexhibit103.htm) | | |

| [removed: 10.10*] [added: 10.9*] | | | | | | [Form of performance unit award agreement under the Biogen Inc. 2017 Omnibus Equity Plan. Filed as Exhibit 10.4 to our Quarterly Report on Form 10-Q for the quarter ended June 30, 2017.](http://www.sec.gov/Archives/edgar/data/875045/000087504517000024/biib-2017630xexhibit104.htm) | | |

| [removed: 10.11*] [added: 10.10*] | | | | | | [Form of cash-settled performance unit award agreement under the Biogen Inc. 2017 Omnibus Equity Plan. Filed as Exhibit 10.5 to our Quarterly Report on Form 10-Q for the quarter ended June 30, 2017.](http://www.sec.gov/Archives/edgar/data/875045/000087504517000024/biib-2017630xexhibit105.htm) | | |

| [removed: 10.12*] [added: 10.11*] | | | | | | [Form of performance stock units award agreement (cash-settled) under the Biogen Inc. 2017 Omnibus Equity Plan. Filed as Exhibit 10.10 to our Annual Report on Form 10-K for the year ended December 31, 2017.](http://www.sec.gov/Archives/edgar/data/875045/000087504518000005/biib-20171231xex1010.htm) | | |

| [removed: 10.13*] [added: 10.12*] | | | | | | [Form of performance stock units award agreement under the Biogen Inc. 2017 Omnibus Equity Plan. Filed as Exhibit 10.11 to our Annual Report on Form 10-K for the year ended December 31, 2017.](http://www.sec.gov/Archives/edgar/data/875045/000087504518000005/biib-20171231xex1011.htm) | | |

| [removed: 10.14*] [added: 10.13*] | | | | | | [Form of performance stock units award agreement under the Biogen Inc. 2017 Omnibus Equity Plan. Filed as Exhibit 10.1 to our Quarterly Report on Form 10-Q for the quarter ended March 31, 2018.](http://www.sec.gov/Archives/edgar/data/875045/000087504518000010/biib-2018331xex101.htm) | | |

| [removed: 10.15*] [added: 10.14*] | | | | | | [Form of performance stock units award agreement (cash settled) under the Biogen Inc. 2017 Omnibus Equity Plan. Filed as Exhibit 10.2 to our Quarterly Report on Form 10-Q for the quarter ended March 31, 2018.](http://www.sec.gov/Archives/edgar/data/875045/000087504518000010/biib-2018331xex102.htm) | | |

| 10.16* | | | | | | [Form of [removed: restricted] [added: performance] stock [removed: unit] [added: units] award agreement [removed: (2018 one-time transition grant)] under the Biogen Inc. 2017 Omnibus Equity [removed: Plan.] [added: Plan (for grants commencing in July 2019).] Filed as Exhibit [removed: 10.3] [added: 10.2] to our Quarterly Report on Form 10-Q for the quarter ended [removed: March 31, 2018.](http://www.sec.gov/Archives/edgar/data/875045/000087504518000010/biib-2018331xex103.htm)] [added: June 30, 2019.](http://www.sec.gov/Archives/edgar/data/875045/000087504519000029/biib-2019630xex102.htm)] | | |

| [removed: 10.17*] [added: 10.15*] | | | | | | [Form of market stock unit award agreement under the Biogen Inc. 2017 Omnibus Equity Plan (for grants commencing in July 2019). Filed as Exhibit 10.1 to our Quarterly Report on Form 10-Q for the quarter ended June 30, 2019.](http://www.sec.gov/Archives/edgar/data/875045/000087504519000029/biib-2019630xex101.htm) | | |

| [removed: 10.18*] [added: 10.17*] | | | | | | [Form of performance stock units award agreement [added: (cash settled)] under the Biogen Inc. 2017 Omnibus Equity Plan (for grants commencing in July 2019). Filed as Exhibit [removed: 10.2] [added: 10.3] to our Quarterly Report on Form 10-Q for the quarter ended June 30, [removed: 2019.](http://www.sec.gov/Archives/edgar/data/875045/000087504519000029/biib-2019630xex102.htm)] [added: 2019.](http://www.sec.gov/Archives/edgar/data/875045/000087504519000029/biib-2019630xex103.htm)] | | |

| [removed: 10.19*] [added: 10.22*] | | | | | | [removed: [Form of performance stock units award agreement (cash settled) under the Biogen] [added: [Biogen] Inc. [removed: 2017 Omnibus Equity Plan (for grants commencing in July 2019).] [added: 2019 Form of Performance-Based Management Incentive Plan, as amended.] Filed as Exhibit [removed: 10.3] [added: 10.1] to our Quarterly Report on Form 10-Q for the quarter ended June 30, [removed: 2019.](http://www.sec.gov/Archives/edgar/data/875045/000087504519000029/biib-2019630xex103.htm)] [added: 2021.](http://www.sec.gov/Archives/edgar/data/875045/000087504519000017/biib-2019331xex101.htm)] | | |

| [removed: 10.20+] [added: 10.18*] | | | | | | [Form of [removed: nonqualified](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit10ormofnonqualified.htm) [stock option](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit10ormofnonqualified.htm) [award agreement](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit10ormofnonqualified.htm) [under Biogen](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit10ormofnonqualified.htm) [Inc.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit10ormofnonqualified.htm) [2017](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit10ormofnonqualified.htm) [Omnibus] [added: nonqualified stock option award agreement under Biogen Inc. 2017 Omnibus] Equity [removed: Plan.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit10ormofnonqualified.htm)] [added: Plan. Filed as Exhibit 10.20 to our Annual Report on Form 10-K for the year ended December 31, 2022.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit10ormofnonqualified.htm)] | | |

| [removed: 10.21*] [added: 10.19*] | | | | | | [Biogen [removed: Idec] Inc. [removed: 2008 Amended and Restated Omnibus] [added: 2006 Non-Employee Directors] Equity [removed: Plan.] [added: Plan, as amended.] Filed as Exhibit [removed: 10.1] [added: 10.2] to our Quarterly Report on Form 10-Q for the quarter ended March 31, [removed: 2014.](http://www.sec.gov/Archives/edgar/data/875045/000087504514000011/biib-2014331xex101.htm)] [added: 2022.](https://www.sec.gov/Archives/edgar/data/875045/000087504522000016/exhibit102biogeninc2006non.htm)] | | |

| [removed: 10.23*] [added: 10.24*] | | | | | | [removed: [Form of market stock unit award agreement under the Biogen] [added: [Biogen] Idec Inc. [removed: 2008 Omnibus Equity Plan.] [added: Supplemental Savings Plan, as amended.] Filed as Exhibit [removed: 10.3] [added: 10.23] to our [removed: Quarterly] [added: Annual] Report on Form [removed: 10-Q] [added: 10-K] for the [removed: quarter] [added: year] ended [removed: March] [added: December] 31, [removed: 2014.](http://www.sec.gov/Archives/edgar/data/875045/000087504514000011/biib-2014331xex103.htm)] [added: 2015.](http://www.sec.gov/Archives/edgar/data/875045/000087504516000042/biib-20151231xex1023.htm)] | | |

| [removed: 10.27*] [added: 10.25*] | | | | | | [Biogen [added: Idec] Inc. [removed: 2006 Non-Employee] [added: Voluntary Board of] Directors [removed: Equity] [added: Savings] Plan, as amended. Filed as Exhibit [removed: 10.2] [added: 10.24] to our [removed: Quarterly] [added: Annual] Report on Form [removed: 10-Q] [added: 10-K] for the [removed: quarter] [added: year] ended [removed: March] [added: December] 31, [removed: 2022.](https://www.sec.gov/Archives/edgar/data/875045/000087504522000016/exhibit102biogeninc2006non.htm)] [added: 2015.](http://www.sec.gov/Archives/edgar/data/875045/000087504516000042/biib-20151231xex1024.htm)] | | |

| [removed: 10.28*] [added: 10.20*] | | | | | | [Biogen Inc. 2015 Employee Stock Purchase Plan. Filed as Appendix A to our Definitive Proxy Statement on Schedule 14A filed on April 30, 2015.](http://www.sec.gov/Archives/edgar/data/875045/000119312515159387/d786327ddef14a.htm#toc786327_57) | | |

| [removed: 10.29*] [added: 10.21*] | | | | | | [Biogen Idec Inc. 2008 Performance-Based Management Incentive Plan. Filed as Appendix B to our Definitive Proxy Statement on Schedule 14A filed on May 8, 2008.](http://www.sec.gov/Archives/edgar/data/875045/000095013508003542/b67068dfdefc14a.htm#152) | | |

| [removed: 10.30*] [added: 10.27*] | | | | | | [removed: [Biogen Inc. 2019 Form] [added: [Annual Retainer Summary for Board] of [removed: Performance-Based Management Incentive Plan, as amended.] [added: Directors (effective January 1, 2020).] Filed as Exhibit 10.1 to our Quarterly Report on Form 10-Q for the quarter ended [removed: June] [added: September] 30, [removed: 2021.](http://www.sec.gov/Archives/edgar/data/875045/000087504519000017/biib-2019331xex101.htm)] [added: 2019.](http://www.sec.gov/Archives/edgar/data/875045/000087504519000041/biib-2019930xex101.htm)] | | |

| [removed: 10.31*] [added: 10.23*] | | | | | | [Biogen Idec Inc. Voluntary Executive Supplemental Savings Plan, as amended and restated effective January 1, 2004. Filed as Exhibit 10.13 to our Annual Report on Form 10-K for the year ended December 31, 2003.](http://www.sec.gov/Archives/edgar/data/875045/000095013504001180/b48790biexv10w13.txt) | | |

| [removed: 10.34*] [added: 10.26*] | | | | | | [Biogen Inc. Executive Severance Policy - U.S. Executive Vice President, as amended effective [removed: June 19, 2019.] [added: July 13, 2020.] Filed as Exhibit [removed: 10.4] [added: 10.1] to our Quarterly Report on Form 10-Q for the quarter ended [removed: June] [added: September] 30, [removed: 2019.](http://www.sec.gov/Archives/edgar/data/875045/000087504519000029/biib-2019630xex104.htm)] [added: 2020.](https://www.sec.gov/Archives/edgar/data/875045/000087504520000036/exhibit101-severancepo.htm)] | | |

| [removed: 10.35*] [added: 10.30*] | | | | | | [removed: [Biogen Inc. Executive Severance Policy - U.S. Executive Vice President, as amended effective] [added: [Letter regarding employment arrangement of Michael McDonnell dated] July [removed: 13,] [added: 16,] 2020. Filed as Exhibit [removed: 10.1] [added: 10.2] to our Quarterly Report on Form 10-Q for the quarter ended September 30, [removed: 2020.](https://www.sec.gov/Archives/edgar/data/875045/000087504520000036/exhibit101-severancepo.htm)] [added: 2020.](https://www.sec.gov/Archives/edgar/data/875045/000087504520000036/exhibit102-mcdonnellof.htm)] | | |

| [removed: 10.37*] [added: 10.28*] | | | | | | [Form of indemnification agreement for directors and executive officers. Filed as Exhibit 10.1 to our Current Report on Form 8-K filed on June 7, 2011.](http://www.sec.gov/Archives/edgar/data/875045/000095012311057276/b86869exv10w1.htm) | | |

| [removed: 10.40*] [added: 10.37] | | | | | | [removed: [Employment] [added: [First Amendment to Amended and Restated Collaboration] Agreement, dated [removed: November 10,] [added: March 13,] 2022, [removed: by and] between Biogen [added: MA] Inc. and [removed: Christopher A. Viehbacher.] [added: Eisai Co., LTD.] Filed as Exhibit [removed: 10.1] [added: 10.46] to our [removed: Current] [added: Annual] Report on Form [removed: 8-K filed on November 10, 2022.](https://www.sec.gov/Archives/edgar/data/875045/000119312522281950/d419645dex101.htm)] [added: 10-K for the year ended December 31, 2022.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit1046firstamendmentt.htm)] | | |

| [removed: 10.41*] [added: 10.31*] | | | | | | [Letter regarding employment arrangement of [removed: Michael McDonnell] [added: Susan Alexander] dated [removed: July 16, 2020.] [added: December 13, 2005.] Filed as Exhibit [removed: 10.2] [added: 10.58] to our [removed: Quarterly] [added: Annual] Report on Form [removed: 10-Q] [added: 10-K] for the [removed: quarter] [added: year] ended [removed: September 30, 2020.](https://www.sec.gov/Archives/edgar/data/875045/000087504520000036/exhibit102-mcdonnellof.htm)] [added: December 31, 2009.](http://www.sec.gov/Archives/edgar/data/875045/000095012310010528/b77985exv10w58.htm)] | | |

| [removed: 10.45+] [added: 10.36] | | | | | | [Amended and Restated Collaboration Agreement, dated October 22, 2017, between Biogen MA Inc. and Eisai Co., [removed: LTD.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit1045amendedandresta.htm)] [added: LTD. Filed as Exhibit 10.45 to our Annual Report on Form 10-K for the year ended December 31, 2022.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit1045amendedandresta.htm)] | | |

| 21+ | | | | | | [removed: [Subsidiaries.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/biib-20221231xex21.htm)] [added: [Subsidiaries.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/biib-20231231xex21.htm)] | | |

| 23+ | | | | | | [Consent of PricewaterhouseCoopers LLP, an Independent Registered Public Accounting [removed: Firm.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/biib-20221231xex23.htm)] [added: Firm.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/biib-20231231xex23.htm)] | | |

| 31.1+ | | | | | | [Certification of the Chief Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of [removed: 2002.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/biib-20221231xex311.htm)] [added: 2002.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/biib-20231231xex311.htm)] | | |

| 31.2+ | | | | | | [Certification of the Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of [removed: 2002.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/biib-20221231xex312.htm)] [added: 2002.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/biib-20231231xex312.htm)] | | |

| 32.1++ | | | | | | [Certification of the Chief Executive Officer and the Chief Financial Officer pursuant to Section 906 of the Sarbanes-Oxley Act of [removed: 2002.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/biib-20221231xex321.htm)] [added: 2002.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/biib-20231231xex321.htm)] | | |

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[T](#ie5989ff7709d49d194ee19ecbcc140c3_10)[able of Contents](#ie5989ff7709d49d194ee19ecbcc140c3_10)

| 10.32*+ | | | | | | [L](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1032-salexanderamen.htm)[etter amending employment arrangement](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1032-salexanderamen.htm) [of Susan Alexander dated February 28, 2020.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1032-salexanderamen.htm) | | |

| 10.33*+ | | | | | | [L](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1033-rachidemployme.htm)[etter regarding employment arrangement of Rachid Izzar dated August](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1033-rachidemployme.htm) [1, 2019.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1033-rachidemployme.htm) | | |

| 10.34* | | | | | | [L](https://www.sec.gov/Archives/edgar/data/875045/000087504523000016/exhibit103-nmurphyofferlet.htm)[etter regarding employment arrangement of Nicole Murphy dated January 28, 2022. Filed as Exhi](https://www.sec.gov/Archives/edgar/data/875045/000087504523000016/exhibit103-nmurphyofferlet.htm)[bit 10.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000016/exhibit103-nmurphyofferlet.htm)[3 to our Q](https://www.sec.gov/Archives/edgar/data/875045/000087504523000016/exhibit103-nmurphyofferlet.htm)[uarterly Report on Form 10-Q for the quarter ended Mar](https://www.sec.gov/Archives/edgar/data/875045/000087504523000016/exhibit103-nmurphyofferlet.htm)[ch 31, 20](https://www.sec.gov/Archives/edgar/data/875045/000087504523000016/exhibit103-nmurphyofferlet.htm)[2](https://www.sec.gov/Archives/edgar/data/875045/000087504523000016/exhibit103-nmurphyofferlet.htm)[3](https://www.sec.gov/Archives/edgar/data/875045/000087504523000016/exhibit103-nmurphyofferlet.htm)[.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000016/exhibit103-nmurphyofferlet.htm) | | |

| 10.35+ | | | | | | [J](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1035-jvatermination.htm)[VA Termination](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1035-jvatermination.htm) [Agreement](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1035-jvatermination.htm)[, by and among Biogen Therap](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1035-jvatermination.htm)[eutics](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1035-jvatermination.htm) [Inc.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1035-jvatermination.htm)[, Samsung BioLogics Co., Ltd. and Samsung Bioepis Co., Ltd, dated April 20, 2020.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit1035-jvatermination.htm) | | |

| 97.1+ | | | | | | [Policy relating to recovery of erroneously awarded compensation.](https://www.sec.gov/Archives/edgar/data/875045/000087504524000009/exhibit971-clawbackpolicy.htm) | | |

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[T](#ie5989ff7709d49d194ee19ecbcc140c3_10)[able of Contents](#ie5989ff7709d49d194ee19ecbcc140c3_10)

| /S/ SUSAN LANGER | | | | | | Director | | | | | | February 13, 2024 | | |

| Susan Langer | | | | | | | | | | | | | | |

| /S/ MONISH PATOLAWALA | | | | | | Director | | | | | | February 13, 2024 | | |

| Monish Patolawala | | | | | | | | | | | | | | |

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[T](#ie5989ff7709d49d194ee19ecbcc140c3_10)[able of Contents](#ie5989ff7709d49d194ee19ecbcc140c3_10)

BIOGEN INC. AND SUBSIDIARIES

| Contract manufacturing, royalty and other revenue | | | | | | 899.3 | | | | | | 485.1 | | | | | | 476.3 | | |

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BIOGEN INC. AND SUBSIDIARIES

| Net income attributable to Biogen Inc. | | | | | | $ | 1,161.1 | | | | | $ | 3,046.9 | | | | | $ | 1,556.1 | |

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BIOGEN INC. AND SUBSIDIARIES

| Accounts receivable, net of allowance for doubtful accounts of $2.4 and $2.3, respectively | | | 1,664.1 | | | | | | 1,705.0 | | |

| Goodwill | | | 6,219.2 | | | | | | 5,749.0 | | |

| Current portion of term loan | | | $ | 150.0 | | | | | $ | — | |

| Notes payable and term loan | | | 6,788.2 | | | | | | 6,281.0 | | |

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BIOGEN INC. AND SUBSIDIARIES

| Amortization of inventory step-up | | | 31.5 | | | | | | — | | | | | | — | | |

| Acquisition of Reata, net of cash acquired | | | (6,926.1) | | | | | | — | | | | | | — | | |

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BIOGEN INC. AND SUBSIDIARIES

| Balance, December 31, 2022 | | | — | | | | | | $ | — | | | | | 167.9 | | | | | | $ | 0.1 | | | | | $ | 73.3 | | | | | $ | (164.9) | | | | | $ | 16,466.5 | | | | | (23.8) | | | | | | $ | (2,977.1) | | | | | $ | 13,397.9 | | | | | $ | (9.5) | | | | | $ | 13,388.4 | |

| Net income | | | — | | | | | | — | | | | | | — | | | | | | — | | | | | | — | | | | | | — | | | | | | 1,161.1 | | | | | | — | | | | | | — | | | | | | 1,161.1 | | | | | | 0.4 | | | | | | 1,161.5 | | |

| Deconsolidation of noncontrolling interest | | | — | | | | | | — | | | | | | — | | | | | | — | | | | | | — | | | | | | — | | | | | | — | | | | | | — | | | | | | — | | | | | | — | | | | | | (3.2) | | | | | | (3.2) | | |

| Balance, December 31, 2023 | | | — | | | | | | $ | — | | | | | 168.7 | | | | | | $ | 0.1 | | | | | $ | 302.5 | | | | | $ | (153.7) | | | | | $ | 17,627.6 | | | | | (23.8) | | | | | | $ | (2,977.1) | | | | | $ | 14,799.4 | | | | | $ | — | | | | | $ | 14,799.4 | |

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BIOGEN INC. AND SUBSIDIARIES

| | | | Preferred stock | | | | | | | | | | | | Common stock | | | | | | | | | | | | Additional paid-in capital | | | | | | Accumulated other comprehensive income (loss) | | | | | | Retained earnings | | | | | | Treasury stock | | | | | | | | | | | | Total Biogen Inc. shareholders’ equity | | | | | | Noncontrolling interests | | | | | | Total equity | | |

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[Table of](#i0cbadda4abfc4b4b9c7e5be15680d793_7) [Conten](#i0cbadda4abfc4b4b9c7e5be15680d793_7)[ts](#i0cbadda4abfc4b4b9c7e5be15680d793_7)

| | | | | | | | | |

| --- | --- | --- | --- | --- | --- | --- | --- | --- |

| Exhibit No. | | | | | | Description | | |

| 4.6 | | | | | | [Form of 3.250% Senior Notes due 2051, in the form of a Global Note bearing a private placement legend. Filed as Exhibit 4.3 to our Current Report on Form 8-K filed on February 16, 2021.](https://www.sec.gov/Archives/edgar/data/875045/000119312521044891/d124092dex43.htm) | | |

| 4.7 | | | | | | [Form of 3.250% Senior Notes due 2051, in the form of a Global Note bearing a Regulation S legend. Filed as Exhibit 4.4 to our Current Report on Form 8-K filed on February 16, 2021.](https://www.sec.gov/Archives/edgar/data/875045/000119312521044891/d124092dex44.htm) | | |

| 4.9 | | | | | | [Registration Rights Agreement, dated February 16, 2021, between Biogen Inc. and Deutsche Bank Securities Inc. and Citigroup Global Markets, Inc. with respect to the 3.250% Senior Notes due 2051. Filed as Exhibit 4.5 to our Current Report on Form 8-K filed on February 16, 2021.](https://www.sec.gov/Archives/edgar/data/875045/000119312521044891/d124092dex45.htm) | | |

| 10.6 | | | | | | [Settlement and License Agreement, dated January 17, 2017, between Biogen Swiss Manufacturing GmbH, Biogen International Holdings ltd., Forward Pharma A/S and other parties thereto. Filed as Exhibit 10.1 to our Current Report on Form 8-K filed on February 1, 2017.](http://www.sec.gov/Archives/edgar/data/875045/000095015717000082/ex10-1.htm) | | |

| 10.22* | | | | | | [Form of performance unit award agreement under the Biogen Idec Inc. 2008 Omnibus Equity Plan. Filed as Exhibit 10.2 to our Quarterly Report on Form 10-Q for the quarter ended March 31, 2014.](http://www.sec.gov/Archives/edgar/data/875045/000087504514000011/biib-2014331xex102.htm) | | |

| 10.24* | | | | | | [Form of restricted stock unit award agreement under the Biogen Idec Inc. 2008 Omnibus Equity Plan. Filed as Exhibit 10.1 to our Current Report on Form 8-K filed on August 1, 2008.](http://www.sec.gov/Archives/edgar/data/875045/000095013508005246/b71469biexv10w1.htm) | | |

| 10.25* | | | | | | [Form of nonqualified stock option award agreement under the Biogen Idec Inc. 2008 Omnibus Equity Plan. Filed as Exhibit 10.2 to our Current Report on Form 8-K filed on August 1, 2008.](http://www.sec.gov/Archives/edgar/data/875045/000095013508005246/b71469biexv10w2.htm) | | |

| 10.26* | | | | | | [Form of cash-settled performance shares award agreement under the Biogen Idec Inc. 2008 Omnibus Equity Plan. Filed as Exhibit 10.1 to our Quarterly Report on Form 10-Q for the quarter ended March 31, 2010.](http://www.sec.gov/Archives/edgar/data/875045/000095012310036233/b79987exv10w1.htm) | | |

| 10.32* | | | | | | [Biogen Idec Inc. Supplemental Savings Plan, as amended. Filed as Exhibit 10.23 to our Annual Report on Form 10-K for the year ended December 31, 2015.](http://www.sec.gov/Archives/edgar/data/875045/000087504516000042/biib-20151231xex1023.htm) | | |

| 10.33* | | | | | | [Biogen Idec Inc. Voluntary Board of Directors Savings Plan, as amended. Filed as Exhibit 10.24 to our Annual Report on Form 10-K for the year ended December 31, 2015.](http://www.sec.gov/Archives/edgar/data/875045/000087504516000042/biib-20151231xex1024.htm) | | |

| 10.36* | | | | | | [Annual Retainer Summary for Board of Directors (effective January 1, 2020). Filed as Exhibit 10.1 to our Quarterly Report on Form 10-Q for the quarter ended September 30, 2019.](http://www.sec.gov/Archives/edgar/data/875045/000087504519000041/biib-2019930xex101.htm) | | |

| 10.38* | | | | | | [Employment Agreement between Biogen Inc. and Michel Vounatsos dated December 18, 2016 and effective as of January 6, 2017. Filed as Exhibit 10.1 to our Current Report on Form 8-K filed on December 19, 2016.](http://www.sec.gov/Archives/edgar/data/875045/000087504516000076/biogenemploymentagreementf.htm) | | |

| 10.39* | | | | | | [Letter regarding employment arrangement of Michel Vounatsos dated May 2, 2022. Filed as Exhibit](https://www.sec.gov/Archives/edgar/data/875045/000087504522000013/exhibit101letteragreement.htm) [10.1 to our](https://www.sec.gov/Archives/edgar/data/875045/000087504522000013/exhibit101letteragreement.htm) [Current Report on Form 8-K filed on May 3, 2022.](https://www.sec.gov/Archives/edgar/data/875045/000087504522000013/exhibit101letteragreement.htm) | | |

| 10.42* | | | | | | [Letter regarding employment arrangement of Susan Alexander dated December 13, 2005. Filed as Exhibit 10.58 to our Annual Report on Form 10-K for the year ended December 31, 2009.](http://www.sec.gov/Archives/edgar/data/875045/000095012310010528/b77985exv10w58.htm) | | |

| 10.43* | | | | | | [Letter regarding employment arrangement of Chirfi Guindo dated October 12, 2017. Filed as Exhibit 10.41 to our Annual Report on Form 10-K for the year ended December 31, 2020.](https://www.sec.gov/Archives/edgar/data/0000875045/000087504521000010/biib-20201231xex1041.htm) | | |

| 10.44 | | | | | | [Joint Venture Agreement, dated December 6, 2011,](https://www.sec.gov/Archives/edgar/data/0000875045/000087504521000028/biib-2021331xex101.htm) [by and between Samsung BioLogics Co., Ltd. and Biogen Therapeutics Inc. (f/k/a Biogen Idec Therapeutics Inc.), as amended February 28, 2012, September 29, 2014, and February 20, 2019. Filed as Exhibit 10.1 to our Quarterly Report on Form 10-Q for the quarter ended March 31, 2021.](https://www.sec.gov/Archives/edgar/data/0000875045/000087504521000028/biib-2021331xex101.htm) | | |

| 10.46+ | | | | | | [First Amendment to Amended and Restated Collaboration Agreement, dated March 13, 2022, between Biogen MA Inc. and Eisai Co., LTD.](https://www.sec.gov/Archives/edgar/data/875045/000087504523000009/exhibit1046firstamendmentt.htm) | | |

| | | | | | | | | | | | | | | |

| Stelios Papadopoulos | | | | | | | | | | | | | | |

| /S/ ALEXANDER J. DENNER | | | | | | Director | | | | | | February 15, 2023 | | |

| Alexander J. Denner | | | | | | | | | | | | | | |

| /S/ CAROLINE D. DORSA | | | | | | Director | | | | | | February 15, 2023 | | |

| /S/ WILLIAM D. JONES | | | | | | Director | | | | | | February 15, 2023 | | |

| William D. Jones | | | | | | | | | | | | | | |

| /S/ RICHARD C. MULLIGAN | | | | | | Director | | | | | | February 15, 2023 | | |

| Richard C. Mulligan | | | | | | | | | | | | | | |

| Other | | | | | | 485.1 | | | | | | 476.3 | | | | | | 774.6 | | |

| Accounts receivable, net | | | 1,705.0 | | | | | | 1,549.4 | | |

| Notes payable | | | 6,281.0 | | | | | | 6,274.0 | | |

| (Gain)/loss on divestiture of Hillerød, Denmark manufacturing operations | | | — | | | | | | — | | | | | | (92.5) | | |

| Purchase of Sangamo Therapeutics, Inc. stock | | | — | | | | | | — | | | | | | (141.8) | | |

| Purchase of Denali Therapeutics Inc. stock | | | — | | | | | | — | | | | | | (423.7) | | |

| Purchase of Sage Therapeutics, Inc. stock | | | — | | | | | | — | | | | | | (441.0) | | |

| Proceeds from divestiture of Hillerød, Denmark manufacturing operations | | | — | | | | | | 28.1 | | | | | | — | | |

| Repayments of borrowings | | | — | | | | | | — | | | | | | (1,500.0) | | |

| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |