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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-Q

☒			QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2025

OR

☐			TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

Commission File Number 0-19311

BIOGEN INC.

(Exact name of registrant as specified in its charter)

Delaware						33-0112644
(State or other jurisdiction of incorporation or organization)						(I.R.S. Employer Identification No.)

225 Binney Street, Cambridge, MA 02142

(617) 679-2000

(Address, including zip code, and telephone number, including

area code, of registrant’s principal executive offices)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class						Trading Symbol(s)						Name of each exchange on which registered
Common Stock, $0.0005 par value						BIIB						The Nasdaq Global Select Market

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days: Yes x No o

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files): Yes x No o

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and "emerging growth company" in Rule 12b-2 of the Exchange Act:

Large accelerated filer			x						Accelerated filer			☐
Non-accelerated filer			☐						Smaller reporting company			☐
									Emerging growth company			☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐ No x

The number of shares of the issuer’s Common Stock, $0.0005 par value, outstanding as of April 30, 2025, was 146,527,832 shares.

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BIOGEN INC.

FORM 10-Q — Quarterly Report

For the Quarterly Period Ended March 31, 2025

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						Page
PART I — FINANCIAL INFORMATION
Item 1.			Financial Statements (unaudited)
			Condensed Consolidated Statements of Income — For the Three Months Ended March 31, 2025 and 2024			8
			Condensed Consolidated Statements of Comprehensive Income — For the Three Months Ended March 31, 2025 and 2024			9
			Condensed Consolidated Balance Sheets — As of March 31, 2025 and December 31, 2024			10
			Condensed Consolidated Statements of Cash Flow — For the Three Months Ended March 31, 2025 and 2024			11
			Condensed Consolidated Statements of Equity — For the Three Months Ended March 31, 2025 and 2024			12
			Notes to Condensed Consolidated Financial Statements			13
Item 2.			Management’s Discussion and Analysis of Financial Condition and Results of Operations			44
Item 3.			Quantitative and Qualitative Disclosures About Market Risk			68
Item 4.			Controls and Procedures			70
PART II — OTHER INFORMATION
Item 1.			Legal Proceedings			71
Item 1A.			Risk Factors			71
Item 2.			Unregistered Sales of Equity Securities and Use of Proceeds			87
Item 5.			Other Information			87
Item 6.			Exhibits			88
Signatures						89

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NOTE REGARDING FORWARD-LOOKING STATEMENTS

This report contains forward-looking statements that are being made pursuant to the provisions of the Private Securities Litigation Reform Act of 1995 (the PSLRA) with the intention of obtaining the benefits of the “Safe Harbor” provisions of the PSLRA. These forward-looking statements may be accompanied by such words as “aim,” “anticipate,” "assume," “believe,” “contemplate,” “continue," "could," “estimate,” “expect,” “forecast,” “goal,” “guidance,” “hope,” “intend,” “may,” “objective,” "outlook," “plan,” “possible,” "potential," “predict,” “project,” “should,” “target,” “will,” “would” or the negative of these words or other words and terms of similar meaning. Given their forward-looking nature, these statements involve substantial risks and uncertainties and may be based on inaccurate assumptions. This report includes, among others, forward-looking statements regarding:

• our expected financial and operating performance;

• our long-term strategy and supporting business plans, including our product pipeline;

• our expectations about continued growth through acquisitions and key collaborative relationships and funding arrangements;

• our belief that our long-term competitive position depends upon our success in discovering and developing innovative, cost-effective products that serve unmet medical needs, along with our ability to manufacture products efficiently and to launch and market them effectively in a highly competitive environment;

• our ability to obtain and maintain adequate coverage, pricing and reimbursement from third-party payors;

• our expectations regarding certain legal and regulatory proceedings and investigations; and

• our belief that our existing funds, when combined with cash generated from operations and our access to additional financing resources, if needed, are sufficient to satisfy our operating, working capital, strategic alliance, milestone payment, capital expenditure and debt service requirements for the foreseeable future.

These forward-looking statements are based on management's current beliefs and assumptions and on information currently available to management. Given their nature, we cannot assure that any outcome expressed in these forward-looking statements will be realized in whole or in part. We caution that these statements are subject to risks and uncertainties, many of which are outside of our control and could cause future events or results to be materially different from those stated or implied in this document, including, among others, factors relating to:

• our substantial dependence on the anticipated amount, timing and accounting of revenue from our products, including from the successful development of new products and approval of additional indications for our existing products, including but not limited to LEQEMBI and SKYCLARYS;

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

• expectations, plans and prospects relating to product approvals, approvals of additional indications for our existing products, sales, pricing, growth, reimbursement and launch of our marketed and pipeline products all of which is subject to governmental and regulatory oversight, and therefore subject to risks, including but not limited to those related to approvals, unfavorable or delayed reimbursements and coverage determinations, and changes in reimbursement policies or practices of payors and other third-parties;

• the potential impact of increased product competition in the biopharmaceutical and healthcare industry, as well as any other markets in which we compete, including increased competition from new originator therapies, generics, prodrugs and biosimilars of existing products and products approved under abbreviated regulatory pathways, including generic, prodrugs or biosimilar versions of our marketed products or competing products, including but not limited to, increased competition from TECFIDERA generic entrants in the U.S. and international markets and a biosimilar entrant of TYSABRI;

• patent terms, patent term extensions, patent office actions and expected availability and periods of regulatory exclusivity, as well as our ability to adequately enforce existing patents, including our European patent related to TECFIDERA;

• our ability to effectively implement our corporate strategy which includes significant investment in product and pipeline candidates, including but not limited to felzartamab, litifilimab and nusinersen;

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• the successful execution of our strategic and growth initiatives, including acquisitions, and our ability to realize the anticipated benefits from our acquisitions of Reata and HI-Bio, including future performance of the SKYCLARYS product and further development of the felzartamab product and anticipated synergies;

• 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, including collaboration agreements, as well as the potential benefits and results of, and the anticipated completion of, certain business development transactions, reorganizations and cost-reduction measures, including our Fit for Growth program;

• the expectations, development plans and anticipated timelines, including costs and timing of potential clinical trials, regulatory filing approvals and/or discontinuation, of our products, drug candidates and pipeline programs, including collaborations with third-parties including but not limited to Eisai and Sage, 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, including those related to our patents and other proprietary and intellectual property rights, tax audits, assessments and settlements, pricing matters, sales and promotional practices, product liability, investigations and other matters;

• our ability to commercialize biosimilars, which is subject to risks such as our reliance on third-parties, competitive challenges, regulatory compliance, adequate supply, intellectual property and regulatory challenges and failure to gain market and patient acceptance;

• our ability to finance our present and future operations and business initiatives and obtain funding for such activities on favorable terms;

• our ability to attract, retain and motivate qualified individuals for management and other employee positions in a highly competitive environment, including potential difficulty in retaining talent following acquisitions or following the discontinuation or underperformance of one or more marketed, pre-clinical or clinical programs;

• adverse safety events involving our marketed or pipeline products, generic, prodrugs or biosimilar versions of our marketed products or any other products from the same class as one of our products;

• the current and potential impacts of geopolitical tensions, acts of war and other large-scale crises, including impacts to our operations, sales and the possible disruptions or delay in our plans to conduct clinical trial activities in areas of geopolitical tension, including tensions between the U.S., China and other countries, regions affected by Russia's invasion of Ukraine and the military conflict in the Middle East;

• the direct and indirect impact of global health outbreaks or adverse weather events on our business and operations, including sales, expense, reserves and allowances, the supply chain, manufacturing, research and development costs, clinical trials and employees;

• our use of information technology systems and data and the potential impacts of any breakdowns, interruptions, invasions, corruptions, data breaches, destructions and/or other cybersecurity incidents of such systems or those of our business partners;

• our incorporation of technologies using AI into some of our processes;

• the potential impact of healthcare reform in the U.S., including the IRA and the impact of the IRA Medicare Part D redesign, 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, as well as the potential impact of legislative and regulatory changes and priorities;

• our manufacturing capacity, including our ability to effectively manufacture biosimilars, reliance on third-party contract manufacturing organizations, plans and timing relating to changes in our manufacturing capabilities, our ability to adequately address global bulk supply risks, our ability to fully utilize our manufacturing facilities, including our Solothurn facility, activities in new or existing manufacturing facilities and the expected timeline for the gene therapy, clinical packaging and other manufacturing facility in RTP, North Carolina to be operational;

• the impact of the continued uncertainty of the credit and economic conditions in certain countries and our ability to collect accounts receivable in such countries;

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• the impact of the increased volatility in the financial markets on our ability to obtain financing;

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

• changes in our effective tax rate and obligations in various jurisdictions in which we are subject to taxation; and

• the impact of new laws, regulatory actions, judicial decisions, accounting standards and tariffs or trade restrictions, including any newly imposed U.S. tariffs and any responsive non-U.S. tariffs applicable to our products or operations, as well as the potential global macroeconomic effect of tariffs or trade restrictions.

These forward-looking statements involve risks and uncertainties, including those that are described in Item 1A. Risk Factors and Item 2. Management's Discussion and Analysis of Financial Condition and Results of Operations included in this report and elsewhere in this report, that could cause actual results to differ materially from those reflected in such statements. The factors identified above should not be construed as an exhaustive list of factors that could affect our future results and should be read in conjunction with the other cautionary statements that are included in our 2024 Form 10-K. 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. Forward-looking statements speak only as of the date of this report and are based on information and estimates available to us at this time. Except as required by law, we do not undertake any obligation to publicly update any forward-looking statements, whether as a result of new information, future developments or otherwise. 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.

NOTE REGARDING COMPANY AND PRODUCT REFERENCES

References in this report to:

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

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

NOTE REGARDING TRADEMARKS

ADUHELM®, AVONEX®, BYOOVIZ®, PLEGRIDY®, QALSODY®, RITUXAN®, RITUXAN HYCELA®, SKYCLARYS®, SPINRAZA®, TECFIDERA®, TYSABRI® and VUMERITY® are registered trademarks of Biogen.

BENEPALI™, FLIXABI™, FUMADERM™, IMRALDI™ and OPUVIZ™ are trademarks of Biogen.

ACTEMRA®, COLUMVI®, ENBREL®, EYLEA®, GAZYVA®, LEQEMBI®, HUMIRA®, LUCENTIS®, LUNSUMIO®, OCREVUS®, REMICADE®, ZURZUVAE™ and other trademarks referenced in this report are the property of their respective owners.

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DEFINED TERMS

2024 Form 10-K			Annual Report on Form 10-K for the year ended December 31, 2024
2020 Share Repurchase Program			Board of Directors authorized program to repurchase up to $5.0 billion of our common stock
2024 ESPP			Biogen Inc. 2024 Employee Stock Purchase Plan
2015 ESPP			Biogen Inc. 2015 Employee Stock Purchase Plan
2023 Term Loan			$1.5 billion term loan credit agreement
AbbVie			AbbVie Inc.
AI			Artificial Intelligence
ALS			Amyotrophic Lateral Sclerosis
AMR			Antibody-Mediated Rejection
AOCI			Accumulated Other Comprehensive Income (Loss)
ASO			Antisense Oligonucleotide
ASU			Accounting Standards Update
BLA			Biologics License Application
CCPA			California Consumer Privacy Act
CLE			Cutaneous Lupus Erythematosus
CLL			Chronic Lymphocytic Leukemia
CMS			Centers for Medicare & Medicaid Services
CODM			Chief Operating Decision Maker
Convergence			Convergence Pharmaceuticals Ltd.
CRL			Complete Response Letter
CROs			Contract Research Organizations
DEA			Drug Enforcement Agency
Denali			Denali Therapeutics Inc.
District Court			U.S. District Court for the District of Massachusetts
DOJ			U.S. Department of Justice
EC			European Commission
Eisai			Eisai Co., Ltd.
EMA			European Medicines Agency
E.U.			European Union
FA			Friedreich Ataxia
FASB			Financial Accounting Standards Board
FCPA			Foreign Corrupt Practices Act
FDA			U.S. Food and Drug Administration
Fit for Growth			Cost saving program initiated in 2023
Genentech			Genentech, Inc.
GILTI			Global Intangible Low Tax Income
GloBE			Global Anti-Base Erosion
GMP			Good Manufacturing Practices
HI-Bio			Human Immunology Biosciences, Inc.
Humana			Humana Inc.
IgAN			Immunoglobulin A Nephropathy
IPR&D			In-process Research and Development
IRA			Inflation Reduction Act of 2022
IT			Information Technology
IV			Intravenous
LRRK2			Leucine-Rich Repeat Kinase 2

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DEFINED TERMS (continued)

MAA			Marketing Authorization Application
MDD			Major Depressive Disorder
MorphoSys			MorphoSys AG
MS			Multiple Sclerosis
NDA			New Drug Application
Neurimmune			Neurimmune SubOne AG
OECD			Organization for Economic Co-operation and Development
ODD			Orphan Drug Designation
Organon			Organon LLC
PDUFA			Prescription Drug User Fee Act
PMN			Primary Membranous Nephropathy
PPACA			Patient Protection and Affordable Care Act
PPD			Postpartum Depression
PPMS			Primary Progressive MS
PRV			Priority Review Voucher
R&D			Research and Development
Reata			Reata Pharmaceuticals, Inc.
RMS			Relapsing MS
RRMS			Relapsing-Remitting MS
RTP			Research Triangle Park
Sage			Sage Therapeutics, Inc.
Samsung Bioepis			Samsung Bioepis Co., Ltd.
Samsung BioLogics			Samsung BioLogics Co., Ltd.
Sangamo			Sangamo Therapeutics, Inc.
SEC			U.S. Securities and Exchange Commission
SG&A			Selling, General and Administrative
SLE			Systemic Lupus Erythematosus
SMA			Spinal Muscular Atrophy
SOD1			Superoxide Dismutase 1
SWISSMEDIC			Swiss Agency for Therapeutic Products
Transition Toll Tax			A one-time mandatory deemed repatriation tax on accumulated foreign subsidiaries' previously untaxed foreign earnings
U.K.			United Kingdom
U.S.			United States
U.S. GAAP			Accounting Principles Generally Accepted in the U.S.
VA			Veterans Affairs
VAT			Value-added Tax

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PART I FINANCIAL INFORMATION

BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF INCOME

(unaudited, in millions, except per share amounts)

			For the Three Months Ended March 31,
			2025						2024
Revenue:
Product revenue, net			$	1,726.5					$	1,711.9
Revenue from anti-CD20 therapeutic programs			378.2						394.0
Alzheimer's collaboration revenue			33.0						2.8
Contract manufacturing, royalty and other revenue			293.3						181.8
Total revenue			2,431.0						2,290.5
Cost and expense:
Cost of sales, excluding amortization and impairment of acquired intangible assets			629.3						542.2
Research and development			434.1						445.4
Acquired in-process research and development, upfront and milestone expense			200.7						7.5
Selling, general and administrative			572.5						581.5
Amortization and impairment of acquired intangible assets			111.8						78.3
Collaboration profit sharing/(loss reimbursement)			58.1						65.6
(Gain) loss on fair value remeasurement of contingent consideration			9.6						—
Restructuring charges			35.3						11.5
Other (income) expense, net			68.4						93.7
Total cost and expense			2,119.8						1,825.7
Income before income tax (benefit) expense			311.2						464.8
Income tax (benefit) expense			70.7						71.4
Net income attributable to Biogen Inc.			$	240.5					$	393.4
Net income per share:
Basic earnings per share attributable to Biogen Inc.			$	1.65					$	2.71
Diluted earnings per share attributable to Biogen Inc.			$	1.64					$	2.70
Weighted-average shares used in calculating:
Basic earnings per share attributable to Biogen Inc.			146.1						145.2
Diluted earnings per share attributable to Biogen Inc.			146.6						145.9

See accompanying notes to these unaudited condensed consolidated financial statements.

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BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

(unaudited, in millions)

			For the Three Months Ended March 31,
			2025						2024
Net income attributable to Biogen Inc.			$	240.5					$	393.4
Other comprehensive income (loss):
Unrealized gains (losses) on cash flow hedges, net of tax			(57.8)						14.7
Unrealized gains (losses) on pension benefit obligation, net of tax			0.4						(0.1)
Currency translation adjustments, net of tax			19.1						(21.4)
Total other comprehensive income (loss), net of tax			(38.3)						(6.8)
Comprehensive income (loss) attributable to Biogen Inc.			$	202.2					$	386.6

See accompanying notes to these unaudited condensed consolidated financial statements.

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BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED BALANCE SHEETS

(unaudited, in millions, except per share amounts)

			As of March 31, 2025						As of December 31, 2024
ASSETS
Current assets:
Cash and cash equivalents			$	2,598.3					$	2,375.0
Accounts receivable, net of allowance for doubtful accounts of $1.4 and $2.2, respectively			1,602.9						1,404.8
Due from anti-CD20 therapeutic programs			393.6						464.0
Inventory			2,273.9						2,460.5
Other current assets			757.3						752.5
Total current assets			7,626.0						7,456.8
Property, plant and equipment, net			3,132.4						3,181.3
Operating lease assets			346.4						356.4
Intangible assets, net			9,584.6						9,691.2
Goodwill			6,477.1						6,478.9
Deferred tax asset			307.5						324.2
Investments and other assets			559.1						560.5
Total assets			$	28,033.1					$	28,049.3
LIABILITIES AND EQUITY
Current liabilities:
Current portion of notes payable			$	1,749.1					$	1,748.6
Taxes payable			626.1						548.3
Accounts payable			391.5						424.2
Accrued expense and other			2,530.7						2,807.7
Total current liabilities			5,297.4						5,528.8
Notes payable			4,548.7						4,547.2
Deferred tax liability			133.2						190.5
Long-term operating lease liabilities			323.4						334.5
Other long-term liabilities			751.7						732.3
Total liabilities			11,054.4						11,333.3
Commitments, contingencies and guarantees
Equity:
Biogen Inc. shareholders’ equity:
Preferred stock, par value $0.001 per share			—						—
Common stock, par value $0.0005 per share			0.1						0.1
Additional paid-in capital			629.9						569.4
Accumulated other comprehensive income (loss)			(174.5)						(136.2)
Retained earnings			19,500.3						19,259.8
Treasury stock, at cost			(2,977.1)						(2,977.1)
Total equity			16,978.7						16,716.0
Total liabilities and equity			$	28,033.1					$	28,049.3

See accompanying notes to these unaudited condensed consolidated financial statements.

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BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOW

(unaudited, in millions)

			For the Three Months Ended March 31,
			2025						2024
Cash flow from operating activities:
Net income			$	240.5					$	393.4
Adjustments to reconcile net income to net cash flow from operating activities:
Depreciation and amortization			183.2						147.5
Excess and obsolescence charges related to inventory			7.3						27.5
Amortization of acquired inventory step-up			51.4						44.1
Share-based compensation			81.0						72.8
Contingent consideration			9.6						—
Deferred income taxes			(27.8)						39.9
(Gain) loss on strategic investments			40.9						31.3
Other			6.7						25.4
Changes in operating assets and liabilities, net of effects of business acquired:
Accounts receivable			(181.0)						43.7
Due from anti-CD20 therapeutic programs			70.4						40.7
Inventory			62.0						(77.7)
Accrued expense and other current liabilities			(300.5)						(177.1)
Income tax assets and liabilities			69.1						(2.2)
Other changes in operating assets and liabilities, net			(53.5)						(56.1)
Net cash flow provided by (used in) operating activities			259.3						553.2
Cash flow from investing activities:
Purchases of property, plant and equipment			(37.1)						(45.9)
Acquisitions of intangible assets			(10.0)						(75.0)
Proceeds from sales of strategic investments			—						55.6
Other			(0.2)						(0.7)
Net cash flow provided by (used in) investing activities			(47.3)						(66.0)
Cash flow from financing activities:
Payments related to issuance of stock for share-based compensation arrangements, net			(24.3)						(46.9)
Repayment of borrowings			—						(400.0)
Other			1.3						7.3
Net cash flow provided by (used in) financing activities			(23.0)						(439.6)
Net increase (decrease) in cash and cash equivalents			189.0						47.6
Effect of exchange rate changes on cash and cash equivalents			34.3						(23.1)
Cash and cash equivalents, beginning of the period			2,375.0						1,049.9
Cash and cash equivalents, end of the period			$	2,598.3					$	1,074.4

See accompanying notes to these unaudited condensed consolidated financial statements.

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BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY

(unaudited, in millions)

			For the Three Months Ended March 31, 2025
			Preferred stock												Common stock												Additional paid-in capital						Accumulated other comprehensive income (loss)						Retained earnings						Treasury stock																								Total equity
			Shares						Amount						Shares						Amount															Shares						Amount
Balance, December 31, 2024			—						$	—					169.5						$	0.1					$	569.4					$	(136.2)					$	19,259.8					(23.8)						$	(2,977.1)																	$	16,716.0
Net income			—						—						—						—						—						—						240.5						—						—																		240.5
Other comprehensive income (loss), net of tax			—						—						—						—						—						(38.3)						—						—						—																		(38.3)
Issuance of common stock under stock option and stock purchase plans			—						—						0.2						—						15.2						—						—						—						—																		15.2
Issuance of common stock under stock award plan			—						—						0.6						—						(39.5)						—						—						—						—																		(39.5)
Compensation related to share-based payments			—						—						—						—						84.1						—						—						—						—																		84.1
Other			—						—						—						—						0.7						—						—						—						—																		0.7
Balance, March 31, 2025			—						$	—					170.3						$	0.1					$	629.9					$	(174.5)					$	19,500.3					(23.8)						$	(2,977.1)																	$	16,978.7

			For the Three Months Ended March 31, 2024
			Preferred stock												Common stock												Additional paid-in capital						Accumulated other comprehensive income (loss)						Retained earnings						Treasury stock												Total equity
			Shares						Amount						Shares						Amount															Shares						Amount
Balance, December 31, 2023			—						$	—					168.7						$	0.1					$	302.5					$	(153.7)					$	17,627.6					(23.8)						$	(2,977.1)					$	14,799.4
Net income			—						—						—						—						—						—						393.4						—						—						393.4
Other comprehensive income (loss), net of tax			—						—						—						—						—						(6.8)						—						—						—						(6.8)
Issuance of common stock under stock option and stock purchase plans			—						—						0.1						—						15.7						—						—						—						—						15.7
Issuance of common stock under stock award plan			—						—						0.6						—						(62.6)						—						—						—						—						(62.6)
Compensation related to share-based payments			—						—						—						—						76.1						—						—						—						—						76.1
Other			—						—						—						—						(2.2)						—						—						—						—						(2.2)
Balance, March 31, 2024			—						$	—					169.4						$	0.1					$	329.5					$	(160.5)					$	18,021.0					(23.8)						$	(2,977.1)					$	15,213.0

See accompanying notes to these unaudited condensed consolidated financial statements.

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(unaudited)

Note 1:			Summary of Significant Accounting Policies

References in these notes to "Biogen," the "company," "we," "us" and "our" refer to Biogen Inc. and its consolidated subsidiaries.

Business Overview

Biogen is a global biopharmaceutical company focused on discovering, developing and delivering innovative therapies for people living with serious and complex diseases. We have a broad portfolio of medicines to treat MS, have introduced the first approved treatment for SMA, co-developed treatments to address a defining pathology of Alzheimer’s disease and launched the first approved treatment to target a genetic cause of ALS. We market the first and only drug approved in the U.S., the E.U. and certain international markets for the treatment of FA in adults and adolescents aged 16 years and older. We are focused on advancing our pipeline in neurology, specialized immunology and rare diseases. We support our drug discovery and development efforts through internal research and development programs, external collaborations and acquisitions.

Our marketed products include TECFIDERA, VUMERITY, AVONEX, PLEGRIDY and TYSABRI for the treatment of MS; SPINRAZA for the treatment of SMA; SKYCLARYS for the treatment of FA; QALSODY for the treatment of ALS; and FUMADERM for the treatment of severe plaque psoriasis.

We also have 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. 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 for the treatment of relapsed or refractory follicular lymphoma; COLUMVI, a bispecific antibody for the 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 commercialize a portfolio of biosimilars of advanced biologics including: BENEPALI, an etanercept biosimilar referencing ENBREL; IMRALDI, an adalimumab biosimilar referencing HUMIRA; FLIXABI, an infliximab biosimilar referencing REMICADE; and BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, in certain international markets. We also have commercialization rights related to OPUVIZ, an aflibercept biosimilar referencing EYLEA, in certain international markets.

For additional information on our collaboration arrangements, please read Note 19, Collaborative and Other Relationships, to these unaudited condensed consolidated financial statements (condensed consolidated financial statements).

Basis of Presentation

In the opinion of management, our condensed consolidated financial statements include all adjustments, consisting of normal recurring accruals, necessary for a fair statement of our financial statements for interim periods in accordance with U.S. GAAP. The information included in this quarterly report on Form 10-Q should be read in conjunction with our audited consolidated financial statements and the accompanying notes included in our 2024 Form 10-K. Our accounting policies are described in the Notes to Consolidated Financial Statements in our 2024 Form 10-K and updated, as necessary, in this report. The year-end condensed consolidated balance sheet data presented for comparative purposes was derived from our audited financial statements, but does not include all disclosures required by U.S. GAAP. The results of operations for the three months ended March 31, 2025, are not necessarily indicative of the operating results for the full year or for any other subsequent interim period.

We operate as one operating segment, focused on discovering, developing and delivering innovative therapies for people living with serious and complex diseases.

During the first quarter of 2025 we began presenting acquired in-process research and development, upfront and milestone expense as a separate line item in our condensed consolidated statements of income. Acquired in-process research and development, upfront and milestone expense includes costs incurred in connection with collaboration and license agreements such as upfront and milestone payments and, when applicable, premiums on equity securities and asset acquisitions of acquired in-process research and development, and were previously

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included in research and development expense. Prior periods have been reclassified to conform to the current period presentation. The reclassification had no impact on our total cost and expense, net income attributable to Biogen Inc., earnings per share or total equity.

Consolidation

Our condensed consolidated financial statements reflect our financial statements, those of our wholly-owned subsidiaries and variable interest entities where we are the primary beneficiary. For consolidated entities where we own or are exposed to less than 100.0% of the economics, we record net income (loss) attributable to noncontrolling interests, net of tax in our condensed consolidated statements of income equal to the percentage of the economic or ownership interest retained in such entities by the respective noncontrolling parties. Intercompany balances and transactions are eliminated in consolidation.

In determining whether we are the primary beneficiary of a variable interest entity, we apply a qualitative approach that determines whether we have both (1) the power to direct the economically significant activities of the entity and (2) the obligation to absorb losses of, or the right to receive benefits from, the entity that could potentially be significant to that entity. We continuously assess whether we are the primary beneficiary of a variable interest entity as changes to existing relationships or future transactions may result in us consolidating or deconsolidating one or more of our collaborators or partners.

Use of Estimates

The preparation of our condensed consolidated financial statements requires us to make estimates, judgments and assumptions that may affect the reported amounts of assets, liabilities, equity, revenue and expense and related disclosure of contingent assets and liabilities. On an ongoing basis we evaluate our estimates, judgments and assumptions. We base our estimates on historical experience and on various other assumptions that we believe are reasonable, the results of which form the basis for making judgments about the carrying values of assets, liabilities and equity and the amount of revenue and expense. Actual results may differ from these estimates.

Significant Accounting Policies

There have been no material changes to our significant accounting policies disclosed in Note 1, Summary of Significant Accounting Policies, to our audited consolidated financial statements included in our 2024 Form 10-K.

New Accounting Pronouncements

From time to time, new accounting pronouncements are issued by the FASB or other standard setting bodies that we adopt as of the specified effective date. Unless otherwise discussed below, we do not believe that the adoption of recently issued standards have had or may have a material impact on our condensed consolidated financial statements or disclosures.

Standard						Description						Effective Date						Effects on the financial statements
ASU No. 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures						This standard establishes incremental disaggregation of income tax disclosures pertaining to the effective tax rate reconciliation and income taxes paid. The amendments in this update are required to be applied on a prospective basis with the option to apply it retrospectively.						Annual reporting for fiscal years beginning after December 15, 2024. Early adoption is permitted.						We are currently evaluating the potential impact that this new standard will have on our consolidated financial statements and related disclosures.
ASU No. 2024-03, Income Statement (Subtopic 220-40): Reporting Comprehensive Income - Expense Disaggregation Disclosures						This standard requires disclosure in the notes to the financial statements, at each interim and annual reporting period, of specified information about certain costs and expense including purchases of inventory, employee compensation, depreciation and intangible asset amortization included in each relevant expense caption. This standard also requires a qualitative description of the amounts remaining in relevant expense captions that are not separately disaggregated, as well as disclosure of the total amount of selling expenses, and, in annual reporting periods, an entity’s definition of selling expenses.						Annual reporting for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted.						We are currently evaluating the potential impact that this new standard will have on our consolidated financial statements and related disclosures.

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Note 2:			Acquisitions

Human Immunology Biosciences

On July 2, 2024, we completed the acquisition of all of the issued and outstanding shares of HI-Bio, a privately-held clinical-stage biotechnology company focused on targeted therapies for patients with severe immune-mediated diseases. HI-Bio's lead asset, felzartamab, an anti-CD38 antibody, is currently being evaluated for three leading indications, AMR, PMN and IgAN. Felzartamab has received Breakthrough Therapy Designation and ODD from the FDA for development in the treatment of PMN and AMR. Subsequent to our acquisition, felzartamab received ODD in the E.U. in IgAN and solid organ transplantation. The acquisition of HI-Bio is expected to augment our pipeline and build on our expertise in immunology.

Under the terms of this acquisition, we paid shareholders of HI-Bio approximately $1.15 billion at closing and may pay up to an additional $650.0 million in potential development and regulatory milestone payments. The $1.15 billion paid includes approximately $74.5 million related to HI-Bio's outstanding, non-vested equity awards, inclusive of employer taxes, of which $56.4 million was recognized as share-based compensation payments to settle non-vested equity awards attributable to the post-acquisition service period and therefore not reflected as a component of total purchase price paid. Of the total $56.4 million, we recognized approximately $42.5 million as a charge to research and development expense with the remaining $13.9 million as a charge to selling, general and administrative expense within our consolidated statements of income for the year ended December 31, 2024, included in our 2024 Form 10-K. These amounts were associated with the accelerated vesting of stock options and RSUs previously granted to HI-Bio employees and required no future services to vest.

Upon closing we also paid an additional $43.7 million related to working capital adjustments as of the transaction close date, which was included as a component of total purchase price paid.

We funded this acquisition through available cash on hand and accounted for this acquisition as a business combination using the acquisition method of accounting in accordance with ASC Topic 805, Business Combinations, and recorded assets acquired and liabilities assumed at their respective fair values as of the acquisition date.

In addition to the lead program felzartamab, the HI-Bio pipeline acquired includes izastobart/HIB210, an anti-C5aR1 antibody, and the potential for continued development in a range of complement-mediated diseases.

Purchase Price Consideration

Total consideration transferred for the acquisition of HI-Bio is summarized as follows:

(In millions)						As of July 2, 2024
Cash consideration paid to HI-Bio shareholders(1)						$	1,137.3
Contingent consideration						485.1
Total consideration						$	1,622.4

(1) Represents total consideration paid to shareholders of HI-Bio of $1.15 billion, plus an additional $43.7 million related to working capital adjustments as of the transaction close date, less $56.4 million of cash paid for HI-Bio's outstanding, non-vested equity awards, inclusive of employer taxes, which were recognized as compensation attributable to the post-acquisition service period and therefore not reflected as a component of total consideration.

Contingent Consideration: We may make certain contingent payments to the former shareholders of HI-Bio upon the achievement of certain development and regulatory milestones. As of the acquisition date, the maximum aggregate amount payable for these potential milestones was $650.0 million. The acquisition-date fair value of these milestones was approximately $485.1 million and was estimated utilizing a probability-adjusted discounted cash flow calculation using an appropriate discount rate dependent on the nature and timing of the milestone payments, which ranged from 6.2% to 7.0%, and probabilities of technological and regulatory success ranging from 67.0% to near-certain probability. Of the total contingent consideration, approximately $279.3 million related to milestones classified as short-term and reflected as a component of accrued expense and other with the remaining $205.8 million reflected as a component of other long-term liabilities within our condensed consolidated balance sheets. The short-term liability related to the fourth patient dosed in a Phase 3 clinical trial of felzartamab in a first and second indication, which would trigger milestone payments of $150.0 million each.

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Subsequent changes in the fair value of the contingent consideration obligation are being recognized as (gain) loss on fair value remeasurement of contingent consideration within our condensed consolidated statements of income. This fair value measurement is based on significant inputs that are not observable in the market and thus represent Level 3 fair value measurements. For additional information related to the fair value of this obligation, please read Note 8, Fair Value Measurements, to these condensed consolidated financial statements.

Other Contractual Commitments: We acquired HI-Bio's pre-existing in-license commitments under third-party agreements with MorphoSys, which include tiered royalties on potential future sales of felzartamab and izastobart/HIB210, ranging from high-single digit to mid-teen percentages, as well as potential development, regulatory and commercial milestone payments related to felzartamab and izastobart/HIB210 of up to $130.0 million, $230.0 million and $640.0 million, respectively. These contingencies were not recorded in our financial statements as of the transaction close date because the achievement of these milestones was not considered probable.

Preliminary Purchase Price Allocation

The following table summarizes the preliminary purchase price allocation of the separately identifiable assets acquired and liabilities assumed as of July 2, 2024:

(In millions)																		Amounts Recognized as of Acquisition Date (as adjusted) March 31, 2025
Cash and cash equivalents																		$	62.5
Intangible assets:
IPR&D - felzartamab (IgAN)																		920.0
IPR&D - felzartamab (AMR)																		450.0
IPR&D - felzartamab (PMN)																		265.0
Other clinical programs																		7.9
Prepaid expense and other assets																		1.0
Operating lease assets																		1.2
Accounts payable																		(1.1)
Accrued liabilities																		(35.0)
Deferred tax liability(1)																		(299.3)
Operating lease liabilities																		(1.2)
Total identifiable net assets																		1,371.0
Goodwill(1)																		251.4
Total assets acquired and liabilities assumed																		$	1,622.4

(1) Includes measurement period adjustments recorded during the first quarter of 2025 that decreased deferred tax liability and goodwill by approximately $5.1 million, as a result of certain income tax adjustments.

Intang****ible assets: Intangible assets comprised of $1.6 billion of IPR&D related to HI-Bio's lead asset felzartamab. This includes $920.0 million of IPR&D related to felzartamab indication for IgAN, $450.0 million of IPR&D related to felzartamab indication for AMR and $265.0 million of IPR&D related to felzartamab indication for PMN. The estimated fair values of the program related intangible assets were determined using a multi-period excess earnings method, a form of the income approach, utilizing cash flow analyses and a discount rate of 14.5%. These fair value measurements were based on significant inputs that are not observable in the market and thus represent Level 3 fair value measurements.

Goodwill: Goodwill was calculated as the excess of the consideration transferred over the net assets recognized and represents the future economic benefits arising from the other assets acquired that could not be individually identified and separately recognized. We recognized goodwill of approximately $251.4 million, which includes measurement period adjustments, and is not deductible for tax purposes. The goodwill recognized from our acquisition of HI-Bio is primarily the result of the deferred tax consequences from the transaction recorded for financial statement purposes.

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Acquisition-related expenses: Acquisition-related expense, primarily comprised of advisory and legal fees, and other transaction costs, totaled approximately $2.8 million and were recorded within selling, general and administrative expense within our consolidated statements of income for the year ended December 31, 2024, included in our 2024 Form 10-K.

Assumptions in the Allocations of Purchase Price

The results of operations of HI-Bio, along with the estimated fair values of the assets acquired and liabilities assumed in the HI-Bio acquisition, have been included in our condensed consolidated financial statements since the closing of the HI-Bio acquisition on July 2, 2024.

Our preliminary estimate of the fair value of the specifically identifiable assets acquired and liabilities assumed as of the date of acquisition is subject to the finalization of management's analysis related to certain matters, such as finalizing our assessment of income taxes. The final determination of these fair values will be completed as additional information becomes available but no later than one year from the acquisition date. The final determination may result in asset and liability fair values that are different than the preliminary estimates.

Subsequent to the acquisition date, our results of operations include the results of operations of HI-Bio. HI-Bio operations had an immaterial impact on our results of operations for the three months ended March 31, 2025. Due to the immateriality of HI-Bio's revenue and expense, additional pro forma information combining the results of operations of Biogen and HI-Bio have not been included.

Note 3:			Dispositions

Sale of Joint Venture Equity Interest in Samsung Bioepis

In April 2022 we completed the sale of our 49.9% equity interest in Samsung Bioepis to Samsung BioLogics in exchange for total consideration of approximately $2.3 billion. Under the terms of this transaction, we received approximately $1.0 billion in cash at closing, with approximately $1.3 billion in cash to be deferred over two payments. The first deferred payment of $812.5 million was received in April 2023 and the second deferred payment of $437.5 million was received in April 2024.

For the three months ended March 31, 2024, we recognized a gain of approximately $6.1 million to reflect the change in fair value associated with the passage of time related to the second deferred payment due to us, which was received in April 2024, and recorded in other (income) expense, net within our condensed consolidated statements of income.

For additional information on the sale of our equity interest in Samsung Bioepis, please read Note 3, Dispositions, to our consolidated financial statements included in our 2024 Form 10-K.

Sale of TOFIDENCE

In March 2025 we completed the sale of our regulatory and commercial rights in the U.S. for TOFIDENCE, a tocilizumab biosimilar referencing ACTEMRA, to Organon. Under the terms of this transaction, we will receive a payment of $51.0 million, which we expect to receive in July 2025, and recognized a de minimis loss within our condensed consolidated statements of income for the three months ended March 31, 2025.

Note 4:			Restructuring

2023 Fit for Growth Restructuring Program

In 2023 we initiated cost saving measures as part of our Fit for Growth program to reduce operating costs, while improving operating efficiency and effectiveness. The Fit for Growth program is expected to generate approximately $1.0 billion in gross operating expense savings by the end of 2025, some of which will be reinvested in various initiatives. The Fit for Growth program is currently estimated to include net headcount reductions of approximately 1,400 employees and we expect to incur total restructuring charges ranging from approximately $300.0 million to $310.0 million. As of March 31, 2025, cumulative total restructuring charges incurred in connection with our Fit for Growth program totaled approximately $300.0 million.

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Total charges incurred from our 2023 Fit for Growth program are summarized as follows:

						For the Three Months Ended March 31,
						2025																		2024
(In millions)						Severance Costs						Accelerated Depreciation and Other Costs						Total						Severance Costs						Accumulated Depreciation and Other Costs						Total
Selling, general and administrative						$	—					$	(3.9)					$	(3.9)					$	—					$	1.4					$	1.4
Research and development						—						5.1						5.1						—						4.9						4.9
Restructuring charges						35.3						—						35.3						9.3						—						9.3
Total charges						$	35.3					$	1.2					$	36.5					$	9.3					$	6.3					$	15.6

Other Costs: includes costs associated with items such as asset abandonment and write-offs, facility closure costs, pretax gains and losses resulting from the termination of certain leases, employee non-severance expense, consulting fees and other costs.

Reata Integration

Following the close of our Reata acquisition in September 2023, we implemented an integration plan designed to realize operating synergies through cost savings and avoidance. Under this initiative, we estimate we will incur total integration charges of approximately $35.0 million related to severance and employment costs. These severance and employment costs were substantially incurred during 2023.

Total charges incurred from our Reata integration are summarized as follows:

						For the Three Months Ended March 31,
						2025																		2024
(In millions)						Severance Costs						Accelerated Depreciation and Other Costs						Total						Severance Costs						Accumulated Depreciation and Other Costs						Total
Selling, general and administrative						$	—					$	1.8					$	1.8					$	—					$	1.8					$	1.8
Research and development						—						2.3						2.3						—						2.7						2.7
Restructuring charges						(0.2)						—						(0.2)						2.2						—						2.2
Total charges						$	(0.2)					$	4.1					$	3.9					$	2.2					$	4.5					$	6.7

In connection with our acquisition of Reata we assumed responsibility for a single-tenant, build-to-suit building of approximately 327,400 square feet of office and laboratory space located in Plano, Texas, with an initial lease term of 16 years. We do not intend to occupy this building and are evaluating opportunities to sublease the property. For additional information on our acquisition of Reata, please read Note 2, Acquisitions, to our consolidated financial statements included in our 2024 Form 10-K.

Restructuring Reserve

Charges and spending related to workforce reductions are summarized as follows:

						Workforce Reductions
(In millions)						2025						2024
Restructuring reserve as of January 1						$	31.9																	$	75.4
Expense						35.3																		11.5
Payment						(25.8)																		(42.2)
Foreign currency and other adjustments						(1.0)																		0.8
Restructuring reserve as of March 31						$	40.4																	$	45.5

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Note 5:			Revenue

Product Revenue

Revenue by product is summarized as follows:

						For the Three Months Ended March 31,
						2025																		2024
(In millions)						United States						Rest of World						Total						United States						Rest of World						Total
Multiple Sclerosis:
TECFIDERA						$	39.8					$	166.3					$	206.1					$	43.7					$	210.6					$	254.3
VUMERITY						117.1						21.7						138.8						105.9						21.6						127.5
Total Fumarate						156.9						188.0						344.9						149.6						232.2						381.8
AVONEX						108.6						58.2						166.8						111.2						67.3						178.5
PLEGRIDY						24.1						35.4						59.5						28.6						36.5						65.1
Total Interferon						132.7						93.6						226.3						139.8						103.8						243.6
TYSABRI						200.8						180.7						381.5						213.8						217.5						431.3
FAMPYRA(1)						—						0.3						0.3						—						19.2						19.2
Subtotal: Multiple Sclerosis						490.4						462.6						953.0						503.2						572.7						1,075.9
Rare Disease:
SPINRAZA						154.4						269.5						423.9						148.5						192.8						341.3
SKYCLARYS(2)						69.1						54.8						123.9						73.0						5.0						78.0
QALSODY(3)						7.5						8.0						15.5						4.4						0.2						4.6
Subtotal: Rare Disease						231.0						332.3						563.3						225.9						198.0						423.9
Biosimilars:
BENEPALI						—						111.3						111.3						—						118.7						118.7
IMRALDI						—						47.4						47.4						—						54.8						54.8
FLIXABI						—						13.1						13.1						—						17.8						17.8
BYOOVIZ						4.2						4.7						8.9						3.7						1.9						5.6
TOFIDENCE						0.1						—						0.1						—						—						—
Subtotal: Biosimilars						4.3						176.5						180.8						3.7						193.2						196.9
Other:
ZURZUVAE						27.7						—						27.7						12.4						—						12.4
Other(4)						0.4						1.3						1.7						0.9						1.9						2.8
Subtotal: Other						28.1						1.3						29.4						13.3						1.9						15.2
Total product revenue, net						$	753.8					$	972.7					$	1,726.5					$	746.1					$	965.8					$	1,711.9

(1) Effective January 1, 2025, our collaboration and license agreement for FAMPYRA global commercialization rights was terminated.

(2) SKYCLARYS became commercially available in the E.U. during the first quarter of 2024.

(3) QALSODY became commercially available in the E.U. during the second quarter of 2024.

(4) Other includes FUMADERM and ADUHELM.

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We recognized revenue from two wholesalers accounting for 25.9% and 14.1% of gross product revenue for the three months ended March 31, 2025, compared to 25.6% and 11.7% of gross product revenue for the three months ended March 31, 2024.

An analysis of the change in reserves for discounts and allowances is summarized as follows:

(In millions)						Discounts						Contractual Adjustments						Returns						Total
Balance, December 31, 2024						$	162.7					$	880.8					$	48.1					$	1,091.6
Current provisions relating to sales in current year						185.7						689.7						5.6						881.0
Adjustments relating to prior years						1.4						(31.4)						3.9						(26.1)
Payments/credits relating to sales in current year						(118.3)						(229.6)						(0.1)						(348.0)
Payments/credits relating to sales in prior years						(64.9)						(359.5)						(3.7)						(428.1)
Balance, March 31, 2025						$	166.6					$	950.0					$	53.8					$	1,170.4

The total reserves above, which are included in our condensed consolidated balance sheets, are summarized as follows:

(In millions)						As of March 31, 2025						As of December 31, 2024
Reduction of accounts receivable						$	205.2					$	154.1
Component of accrued expense and other						965.2						937.5
Total revenue-related reserves						$	1,170.4					$	1,091.6

Revenue from Anti-CD20 Therapeutic Programs

Revenue from anti-CD20 therapeutic programs is summarized in the table below. For the purposes of this footnote, we refer to RITUXAN and RITUXAN HYCELA collectively as RITUXAN.

						For the Three Months Ended March 31,
(In millions)						2025						2024
Royalty revenue on sales of OCREVUS						$	288.8					$	302.7
Biogen’s share of pre-tax profits in the U.S. for RITUXAN, GAZYVA and LUNSUMIO						83.7						87.1
Other revenue from anti-CD20 therapeutic programs						5.7						4.2
Total revenue from anti-CD20 therapeutic programs						$	378.2					$	394.0

For additional information on our collaboration arrangements with Genentech, please read Note 19, Collaborative and Other Relationships, to these condensed consolidated financial statements.

Alzheimer's Collaboration Revenue

Alzheimer's collaboration revenue consists of our 50.0% share of LEQEMBI product revenue, net and cost of sales, including royalties, as we are not the principal. We began recognizing Alzheimer's collaboration revenue upon the accelerated approval of LEQEMBI in the U.S. during the first quarter of 2023.

For the three months ended March 31, 2025 and 2024, we recognized approximately $33.0 million and $2.8 million, respectively, of Alzheimer's collaboration revenue within our condensed consolidated statements of income.

For additional information on our collaboration arrangements with Eisai, please read Note 19, Collaborative and Other Relationships, to these condensed consolidated financial statements.

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Contract Manufacturing, Royalty and Other Revenue

Contract manufacturing, royalty and other revenue is summarized as follows:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Contract manufacturing revenue						$	282.3					$	152.2
Royalty and other revenue						11.0						29.6
Total contract manufacturing, royalty and other revenue						$	293.3					$	181.8

Contract Manufacturing Revenue

Contract manufacturing revenue primarily reflects amounts earned under contract manufacturing agreements with our strategic customers and batches of LEQEMBI related to our collaboration with Eisai.

Royalty and Other Revenue

Royalty and other revenue primarily reflects royalty revenue on biosimilar products from our license arrangements with Samsung Bioepis and royalties we receive from net sales on products related to patents that we have out-licensed.

For additional information on our license arrangements with Samsung Bioepis and our collaboration arrangements with Eisai, please read Note 19, Collaborative and Other Relationships, to these condensed consolidated financial statements.

Note 6:			Inventory

The components of inventory are summarized as follows:

(In millions)						As of March 31, 2025						As of December 31, 2024
Raw materials						$	306.4					$	317.8
Work in process						1,717.0						1,882.8
Finished goods						367.9						353.8
Total inventory						$	2,391.3					$	2,554.4
Balance Sheet Classification:
Inventory						$	2,273.9					$	2,460.5
Investments and other assets						117.4						93.9
Total inventory						$	2,391.3					$	2,554.4

Long-term inventory is included in investments and other assets within our condensed consolidated balance sheets.

As a result of our acquisition of Reata in September 2023 we recorded a fair value step-up adjustment related to the acquired inventory of SKYCLARYS of approximately $1.3 billion. This fair value step-up adjustment is being amortized to cost of sales within our condensed consolidated statements of income as the inventory is sold, which we expect will be sold or used by the end of 2028. For the three months ended March 31, 2025 and 2024, amortization from the fair value step-up adjustment was approximately $51.4 million and $44.1 million, respectively. For additional information on our acquisition of Reata, please read Note 2, Acquisitions, to our consolidated financial statements included in our 2024 Form 10-K.

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

Note 7:			Intangible Assets and Goodwill

Intangible Assets

Intangible assets, net of accumulated amortization, impairment charges and adjustments are summarized as follows:

												As of March 31, 2025																		As of December 31, 2024
(In millions)						Estimated Life						Cost						Accumulated Amortization						Net						Cost						Accumulated Amortization						Net
Completed technology						2-31 years						$	14,103.6					$	(6,325.9)					$	7,777.7					$	14,138.4					$	(6,254.1)					$	7,884.3
In-process research and development						Indefinite until commercialization						1,642.9						—						1,642.9						1,642.9						—						1,642.9
Priority review voucher						Indefinite						100.0						—						100.0						100.0						—						100.0
Trademarks and trade names						Indefinite						64.0						—						64.0						64.0						—						64.0
Total intangible assets												$	15,910.5					$	(6,325.9)					$	9,584.6					$	15,945.3					$	(6,254.1)					$	9,691.2

Amortization and Impairments

For the three months ended March 31, 2025, amortization and impairment of acquired intangible assets, totaled $111.8 million, compared to $78.3 million in the prior year comparative period. The increase was primarily due to amortization for the acquired intangible assets associated with SKYCLARYS and TYSABRI.

For the three months ended March 31, 2025 and 2024, we had no impairment charges.

Completed Technology

Completed technology primarily relates to our other marketed products and programs acquired through asset acquisitions, licenses and business combinations. Completed technology intangible assets are amortized over their estimated useful lives, which range between 2 to 31 years, with a remaining weighted average useful life of 12 years.

IPR&D Related to Business Combinations

IPR&D represents the fair value assigned to research and development assets that we acquired as part of a business combination and had not yet reached technological feasibility at the date of acquisition. Included in IPR&D balances are adjustments related to foreign currency exchange rate fluctuations.

The carrying value associated with our IPR&D assets as of March 31, 2025 and December 31, 2024, primarily relates to the IPR&D programs we acquired in connection with our acquisition of HI-Bio in July 2024, with an estimated fair value of approximately $1.6 billion.

Priority Review Voucher

In connection with our acquisition of Reata in September 2023 we acquired a rare pediatric disease PRV which may be used to obtain priority review by the FDA for a future regulatory submission or sold to a third party. We recorded the PRV based on its estimated fair value of $100.0 million as an intangible asset. The estimated fair value of the PRV was based on external purchase and sale transactions of similar vouchers at the time of acquisition.

For additional information on our acquisitions of Reata and HI-Bio, please read Note 2, Acquisitions, to our consolidated financial statements included in our 2024 Form 10-K.

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

Estimated Future Amortization of Intangible Assets

The estimated future amortization of finite-lived intangible assets for the next five years is expected to be as follows:

(In millions)						As of March 31, 2025
2025 (remaining nine months)						$	350.0
2026						560.0
2027						600.0
2028						630.0
2029						665.0
2030						700.0

Goodwill

The following table provides a roll forward of the changes in our goodwill balance:

(In millions)						As of March 31, 2025
Goodwill, December 31, 2024						$	6,478.9
Goodwill resulting from HI-Bio acquisition(1)						(5.1)
Other						3.3
Goodwill, March 31, 2025						$	6,477.1

(1) Goodwill resulting from HI-Bio acquisition for the three months ended March 31, 2025, relates to HI-Bio measurement period adjustments recognized during the first quarter of 2025 related to certain income tax adjustments. For additional information on our acquisition of HI-Bio, please read Note 2, Acquisitions, to these condensed consolidated financial statements.

As of March 31, 2025, we had no accumulated impairment losses related to goodwill. Other includes adjustments related to foreign currency exchange rate fluctuations.

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(unaudited, continued)

Note 8:			Fair Value Measurements

The tables below present information about our assets and liabilities that are regularly measured and carried at fair value and indicate the level within the fair value hierarchy of the valuation techniques we utilized to determine such fair value:

						Fair Value Measurements on a Recurring Basis
						As of March 31, 2025
(In millions)						Total						Quoted Prices in Active Markets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)
Assets:
Cash equivalents						$	2,109.0					$	—					$	2,109.0					$	—
Marketable equity securities						146.9						146.9						—						—
Other current assets:
Derivative contracts						40.2						—						40.2						—
Other non-current assets:
Plan assets for deferred compensation						47.8						—						47.8						—
Total						$	2,343.9					$	146.9					$	2,197.0					$	—
Liabilities:
Other current liabilities:
Derivative contracts						$	32.5					$	—					$	32.5					$	—
Contingent consideration obligations						294.3						—						—						294.3
Other non-current liabilities:
Derivative contracts						0.8						—						0.8						—
Contingent consideration obligations						228.1						—						—						228.1
Total						$	555.7					$	—					$	33.3					$	522.4

						Fair Value Measurements on a Recurring Basis
						As of December 31, 2024
(In millions)						Total						Quoted Prices in Active Markets (Level 1)						Significant Other Observable Inputs (Level 2)						Significant Unobservable Inputs (Level 3)
Assets:
Cash equivalents						$	1,664.9					$	—					$	1,664.9					$	—
Marketable equity securities						179.7						179.7						—						—
Other current assets:
Derivative contracts						62.5						—						62.5						—
Other non-current assets:
Plan assets for deferred compensation						42.8						—						42.8						—
Total						$	1,949.9					$	179.7					$	1,770.2					$	—
Liabilities:
Other current liabilities:
Derivative contracts						$	11.7					$	—					$	11.7					$	—
Contingent consideration obligations						291.2						—						—						291.2
Other non-current liabilities:
Contingent consideration obligations						221.6						—						—						221.6
Total						$	524.5					$	—					$	11.7					$	512.8

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

Our marketable equity securities represent investments in publicly traded equity securities. Our ability to liquidate our investments in Denali and Sage may be limited by the size of our interest, the volume of market related activity, our concentrated level of ownership and potential restrictions resulting from our status as a collaborator. Therefore, we may realize significantly less than the current value of such investments.

For additional information on our investments in Denali and Sage common stock, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in our 2024 Form 10-K.

There have been no material impairments of our assets measured and carried at fair value as of March 31, 2025 and December 31, 2024. In addition, there have been no changes to our valuation techniques as of March 31, 2025 and December 31, 2024.

For a description of our validation procedures related to prices provided by third-party pricing services and our option pricing valuation model, please read Note 1, Summary of Significant Accounting Policies - Fair Value Measurements, to our consolidated financial statements included in our 2024 Form 10-K.

Level 3 Assets and Liabilities Held at Fair Value

The following table presents quantitative information, as of the dates indicated, about the valuation techniques and significant unobservable inputs used in the valuation of our Level 3 financial assets and liabilities measured at fair value on a recurring basis:

						Quantitative Information about Level 3 Fair Value Measurements
						As of March 31, 2025
(In millions)						Fair Value						Valuation Technique						Significant Unobservable Input(s)						Range						Weighted Average
Liabilities:
Contingent consideration obligations						$	522.4					Discounted cash flow						Discount rate						5.8% - 5.9%						5.9		%
																		Expected timing of achievement of development milestones						2025 - 2030						—

The weighted average discount rates were calculated based on the relative fair values of each distinct contingent consideration obligation related to our acquisition of HI-Bio in July 2024. In addition, we apply various probabilities of technological and regulatory success to the valuation models to estimate the fair values of these contingent consideration obligations, which ranged from approximately 70.0% to near certain probability as of March 31, 2025.

There were no transfers of assets or liabilities into or out of Level 3 as of March 31, 2025 and December 31, 2024.

Contingent Consideration Obligations

In connection with our acquisition of HI-Bio in July 2024 we agreed to make additional payments based upon the achievement of certain milestone events. The following table provides a roll forward of the fair value of our contingent consideration obligations, which were classified as Level 3 measurements:

(In millions)						As of March 31, 2025
Fair value, beginning of period						$	512.8
Changes in fair value						9.6
Fair value, end of period						$	522.4

Changes in the fair value of our contingent consideration obligations are recorded in (gain) loss on fair value remeasurement of contingent consideration in our condensed consolidated statements of income. The fair values of the contingent consideration liabilities were based on a probability-adjusted discounted cash flow calculation using Level 3 fair value measurements and inputs. For additional information on the valuation techniques and inputs utilized in the valuation of our financial assets and liabilities, please read Note 1, Summary of Significant Accounting Policies, to our consolidated financial statements included in our 2024 Form 10-K.

As of March 31, 2025, approximately $294.3 million of the fair value of the total contingent consideration obligations were classified as short-term and reflected as a component of accrued expense and other within our condensed consolidated balance sheets with the remaining $228.1 million reflected as a component of other long-term liabilities in our condensed consolidated balance sheets.

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

For the three months ended March 31, 2025, the changes in the fair value of our contingent consideration obligations were primarily due to changes in interest rates used to revalue our contingent consideration liabilities and the passage of time.

Financial Instruments Not Carried at Fair Value

Other Financial Instruments

Due to the short-term nature of certain financial instruments, the carrying value reflected in our condensed consolidated balance sheets for current accounts receivable, due from anti-CD20 therapeutic programs, other current assets, accounts payable and accrued expense and other, approximates fair value.

Debt Instruments

The fair and carrying values of our debt instruments, which are Level 2 liabilities, are summarized as follows:

						As of March 31, 2025												As of December 31, 2024
(In millions)						Fair Value						Carrying Value						Fair Value						Carrying Value
Current portion:
4.050% Senior Notes due September 15, 2025						$	1,746.1					$	1,749.1					$	1,741.0					$	1,748.6
Current portion of notes payable						1,746.1						1,749.1						1,741.0						1,748.6
Non-current portion:
2.250% Senior Notes due May 1, 2030						1,323.3						1,495.0						1,295.6						1,494.7
5.200% Senior Notes due September 15, 2045						1,008.2						1,101.2						1,008.0						1,101.1
3.150% Senior Notes due May 1, 2050						945.4						1,475.1						943.7						1,475.0
3.250% Senior Notes due February 15, 2051						448.7						477.4						448.9						476.4
Non-current portion of notes payable						3,725.6						4,548.7						3,696.2						4,547.2
Total notes payable						$	5,471.7					$	6,297.8					$	5,437.2					$	6,295.8

The fair values of each of our series of Senior Notes were determined through market, observable and corroborated sources. The changes in the fair values of our Senior Notes as of March 31, 2025, compared to December 31, 2024, are primarily related to decreases in U.S. treasury yields, partially offset by increases in credit spreads used to value our Senior Notes since December 31, 2024. For additional information related to our Senior Notes, please read Note 13, Indebtedness, to our consolidated financial statements included in our 2024 Form 10-K.

Note 9:			Financial Instruments

The following table summarizes our financial assets with maturities of less than 90 days from the date of purchase included in cash and cash equivalents in our condensed consolidated balance sheets:

(In millions)						As of March 31, 2025						As of December 31, 2024
Money market funds						$	2,109.0					$	1,664.9
Total						$	2,109.0					$	1,664.9

The carrying value of our money market funds approximates fair value due to their short-term maturities.

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(unaudited, continued)

Our marketable equity securities gains (losses) are recorded in other (income) expense, net in our condensed consolidated statements of income. The following tables summarize our marketable equity securities, classified as available-for-sale:

						As of March 31, 2025
(In millions)						Amortized Cost						Gross Unrealized Gains						Gross Unrealized Losses						Fair Value
Marketable equity securities
Marketable equity securities, non-current						$	668.7					$	—					$	(521.8)					$	146.9
Total marketable equity securities						$	668.7					$	—					$	(521.8)					$	146.9

						As of December 31, 2024
(In millions)						Amortized Cost						Gross Unrealized Gains						Gross Unrealized Losses						Fair Value
Marketable equity securities
Marketable equity securities, non-current						$	668.7					$	—					$	(489.0)					$	179.7
Total marketable equity securities						$	668.7					$	—					$	(489.0)					$	179.7

Strategic Investments

Our strategic investment portfolio includes investments in equity securities of certain biotechnology companies, which are reflected within our disclosures included in Note 8, Fair Value Measurements, to these condensed consolidated financial statements, as well as venture capital funds where the underlying investments are in equity securities of certain biotechnology companies and non-marketable equity securities.

As of March 31, 2025 and December 31, 2024, our strategic investment portfolio was comprised of investments totaling $186.0 million and $226.7 million, respectively, which are included in investments and other assets within our condensed consolidated balance sheets.

The decrease in our strategic investment portfolio for the three months ended March 31, 2025, was primarily due to the decrease in the fair value of our investment in Denali common stock, partially offset by an increase in the fair value of our investment in Sage common stock.

For additional information on our investments in Denali and Sage common stock, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in our 2024 Form 10-K.

Note 10:			Derivative Instruments

Foreign Currency Forward Contracts - Hedging Instruments

Due to the global nature of our operations, portions of our revenue and operating expense are recorded in currencies other than the U.S. dollar. The value of revenue and operating expense measured in U.S. dollars is therefore subject to changes in foreign currency exchange rates. We enter into foreign currency forward contracts and foreign currency options with financial institutions with the primary objective to mitigate the impact of foreign currency exchange rate fluctuations on our international revenue and operating expense.

Foreign currency forward contracts and foreign currency options in effect as of March 31, 2025 and December 31, 2024, had durations of 1 to 15 months and 1 to 12 months, respectively. These contracts have been designated as cash flow hedges and unrealized gains and losses on the portion of these foreign currency forward contracts and foreign currency options that are included in the effectiveness test are reported in AOCI. Realized gains and losses of such contracts and options are recognized in revenue when the sale of product in the currency being hedged is recognized and in operating expense when the expense in the currency being hedged is recorded. We recognize all cash flow hedge reclassifications from AOCI and fair value changes of excluded portions in the same line item in our condensed consolidated statements of income that have been impacted by the hedged item.

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

The notional amount of foreign currency forward contracts and foreign currency options that were entered into to hedge forecasted revenue and operating expense is summarized as follows:

						Notional Amount
(In millions)						As of March 31, 2025						As of December 31, 2024
Euro						$	1,603.6					$	1,062.6
British pound						102.5						133.8
Swiss franc						191.6						—
Canadian dollar						30.2						38.6
Total foreign currency forward contracts and options						$	1,927.9					$	1,235.0

The pre-tax portion of the fair value of these foreign currency forward contracts and foreign currency options that were included in AOCI in total equity is summarized as follows:

(In millions)						As of March 31, 2025						As of December 31, 2024
Unrealized gains						$	16.6					$	50.6
Unrealized (losses)						(30.7)						(0.3)
Net unrealized gains (losses)						$	(14.1)					$	50.3

We expect the net unrealized losses of approximately $14.1 million to be settled over the next 15 months, of which approximately $13.4 million of these net unrealized losses are expected to be settled over the next 12 months, with any amounts in AOCI to be reported as an adjustment to revenue or operating expense. We consider the impact of our and our counterparties’ credit risk on the fair value of the contracts as well as the ability of each party to execute its contractual obligations. As of March 31, 2025 and December 31, 2024, credit risk did not materially change the fair value of our foreign currency forward contracts and forward currency options.

The following tables summarize the effect of foreign currency forward contracts and forward currency options designated as hedging instruments in our condensed consolidated statements of income:

For the Three Months Ended March 31,
Net Gains/(Losses) Reclassified from AOCI into Operating Income (in millions)																		Net Gains/(Losses) Excluded from Effectiveness Testing and Recognized in Operating Income (in millions)
Location						2025						2024						Location						2025						2024
Revenue						$	10.9					$	2.9					Revenue						$	0.4					$	0.2
Operating expense						0.7						(2.1)						Operating expense						(1.0)						(1.2)

Foreign Currency Forward Contracts - Other Derivative Instruments

We also enter into other foreign currency forward contracts, usually with durations of one month or less, to mitigate the foreign currency risk related to certain balance sheet positions. We have not elected hedge accounting for these transactions.

The aggregate notional amount of these outstanding foreign currency forward contracts was $866.7 million and $738.7 million as of March 31, 2025 and December 31, 2024, respectively. Net gains of $7.7 million and net losses of $24.3 million related to these contracts were recorded as a component of other (income) expense, net for the three months ended March 31, 2025 and 2024, respectively.

Summary of Derivative Instruments

While certain of our derivative instruments are subject to netting arrangements with our counterparties, we do not offset derivative assets and liabilities in our condensed consolidated balance sheets. The amounts in the table below would not be substantially different if the derivative assets and liabilities were offset.

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

The following table summarizes the fair value and presentation in our condensed consolidated balance sheets of our outstanding derivative instruments, including those designated as hedging instruments:

(In millions)						Balance Sheet Location						As of March 31, 2025						As of December 31, 2024
Cash Flow Hedging Instruments:
Asset derivative instruments						Other current assets						$	22.6					$	58.4
Liability derivative instruments						Accrued expense and other						28.8						0.3
						Other long-term liabilities						0.8						—
Other Derivative Instruments:
Asset derivative instruments						Other current assets						17.6						4.1
Liability derivative instruments						Accrued expense and other						3.7						11.4

Note 11:			Property, Plant and Equipment

Property, plant and equipment are recorded at historical cost, net of accumulated depreciation. Accumulated depreciation on property, plant and equipment was $2,742.9 million and $2,670.8 million as of March 31, 2025 and December 31, 2024, respectively. For the three months ended March 31, 2025 and 2024, depreciation expense totaled approximately $71.4 million and $69.3 million, respectively.

Note 12:			Leases

New Corporate Headquarters Lease

In March 2025 we entered into a lease agreement with MIT Investment Management Company and BioMed Realty for the lease of approximately 580,000 square feet of office and research and development space located at 75 Broadway, Cambridge, Massachusetts, which will be used as our new global corporate headquarters. The new lease is intended to replace two existing leases, both in Cambridge, Massachusetts, including our current corporate headquarters. We expect the initial lease term of approximately 15.5 years to commence on May 31, 2028. The estimated minimum lease payments as a result of the new lease total approximately $1.5 billion over the initial lease term. We have an option to extend the lease for three extension periods of five years each and one six month short-term extension, at then market-based rates. We will account for this lease as a right-of-use asset and lease liability upon the lease commencement date.

For additional information on our accounting policies relating to leases, please read Note 1, Summary of Significant Accounting Policies - Leases, to our consolidated financial statements included in our 2024 Form 10-K.

Note 13:			Indebtedness

2023 Term Loan Credit Agreement

In connection with our acquisition of Reata in September 2023 we entered into a $1.5 billion term loan credit agreement. On the closing date of the Reata acquisition we drew $1.0 billion from the 2023 Term Loan, comprised of a $500.0 million floating rate 364-day tranche and a $500.0 million floating rate three-year tranche. The remaining unused commitment of $500.0 million was terminated. As of December 31, 2023, we repaid $350.0 million of the 364--day tranche. The remaining $150.0 million portion of the 364-day tranche was repaid during the first quarter of 2024.

Additionally, during the first quarter of 2024 we repaid $250.0 million of the three-year tranche, with the remaining $250.0 million portion being subsequently repaid in full during the second quarter of 2024. For additional information on our acquisition of Reata, please read Note 2, Acquisitions, to our consolidated financial statements included in our 2024 Form 10-K.

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

Note 14:			Equity

Share Repurchases

In October 2020 our Board of Directors authorized our 2020 Share Repurchase Program, which is a program to repurchase up to $5.0 billion of our common stock. Our 2020 Share Repurchase Program does not have an expiration date. All shares repurchased under our 2020 Share Repurchase Program were retired. There were no share repurchases of our common stock during the three months ended March 31, 2025 and 2024. Approximately $2.1 billion remained available under our 2020 Share Repurchase Program as of March 31, 2025.

Accumulated Other Comprehensive Income (Loss)

The following tables summarize the changes in AOCI, net of tax by component:

												For the Three Months Ended March 31, 2025
(In millions)												Unrealized Gains (Losses) on Cash Flow Hedges, Net of Tax												Unrealized Gains (Losses) on Pension Benefit Obligation, Net of Tax						Currency Translation Adjustments, Net of Tax						Total
Balance, December 31, 2024												$	51.6											$	(16.6)					$	(171.2)					$	(136.2)
Other comprehensive income (loss) before reclassifications												(47.5)												0.4						19.1						(28.0)
Amounts reclassified from AOCI												(10.3)												—						—						(10.3)
Net current period other comprehensive income (loss)												(57.8)												0.4						19.1						(38.3)
Balance, March 31, 2025												$	(6.2)											$	(16.2)					$	(152.1)					$	(174.5)

												For the Three Months Ended March 31, 2024
(In millions)												Unrealized Gains (Losses) on Cash Flow Hedges, Net of Tax												Unrealized Gains (Losses) on Pension Benefit Obligation, Net of Tax						Currency Translation Adjustments, Net of Tax						Total
Balance, December 31, 2023												$	(25.0)											$	(2.6)					$	(126.1)					$	(153.7)
Other comprehensive income (loss) before reclassifications												15.4												(0.1)						(21.4)						(6.1)
Amounts reclassified from AOCI												(0.7)												—						—						(0.7)
Net current period other comprehensive income (loss)												14.7												(0.1)						(21.4)						(6.8)
Balance, March 31, 2024												$	(10.3)											$	(2.7)					$	(147.5)					$	(160.5)

The following table summarizes the amounts reclassified from AOCI:

(In millions)						Amounts Reclassified from AOCI												Income Statement Location
			For the Three Months Ended March 31,
			2025						2024
Gains (losses) on cash flow hedges						$	10.9					$	2.9																	Revenue
						0.7						(2.1)																		Operating expense
						(0.1)						0.1																		Other (income) expense, net
						(1.2)						(0.2)																		Income tax (benefit) expense
Total reclassifications, net of tax						$	10.3					$	0.7

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

Note 15:			Earnings per Share

Basic and diluted shares outstanding used in our earnings per share calculation are calculated as follows:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Numerator:
Net income attributable to Biogen Inc.						$	240.5					$	393.4
Denominator:
Weighted average number of common shares outstanding						146.1						145.2
Effect of dilutive securities:
Time-vested restricted stock units						0.5						0.5
Performance stock units settled in stock						—						0.2
Dilutive potential common shares						0.5						0.7
Shares used in calculating diluted earnings per share						146.6						145.9

Amounts excluded from the calculation of net income per diluted share because their effects were anti-dilutive were insignificant.

Note 16:			Share-Based Payments

Share-based Compensation Expense

The following table summarizes share-based compensation expense included in our condensed consolidated statements of income:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Research and development						$	32.1					$	27.4
Selling, general and administrative						52.0						44.0
Subtotal						84.1						71.4
Capitalized share-based compensation costs						(3.1)						(3.3)
Share-based compensation expense included in total cost and expense						81.0						68.1
Income tax effect						(16.0)						(12.9)
Share-based compensation expense included in net income attributable to Biogen Inc.						$	65.0					$	55.2

The following table summarizes share-based compensation expense associated with each of our share-based compensation programs:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Time-vested restricted stock units						$	66.1					$	57.3
Performance stock units settled in stock						13.6						10.5
Employee stock purchase plan						3.5						4.5
Performance stock units settled in cash						—						(2.1)
Stock options						0.9						0.9
Market stock units						—						0.3
Subtotal						84.1						71.4
Capitalized share-based compensation costs						(3.1)						(3.3)
Share-based compensation expense included in total cost and expense						$	81.0					$	68.1

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(unaudited, continued)

We estimate the fair value of our obligations associated with our performance stock units settled in cash at the end of each reporting period through expected settlement. Cumulative adjustments to these obligations are recognized each quarter to reflect changes in the stock price and estimated outcome of the performance-related conditions.

Note 17:			Income Taxes

Tax Rate

A reconciliation between the U.S. federal statutory tax rate and our effective tax rate is summarized as follows:

			For the Three Months Ended March 31,
			2025						2024
Statutory rate			21.0		%				21.0		%
State taxes			1.9						1.5
Taxes on foreign earnings, including valuation allowances			(9.9)						(3.7)
Tax credits			(1.9)						(2.5)
Purchased inventory valuation step-up and intangible assets			2.7						1.3
GILTI			1.3						(2.7)
Share-based compensation awards			5.5						0.7
Other, including permanent items			2.1						(0.2)
Effective tax rate			22.7		%				15.4		%

Changes in Tax Rate

For the three months ended March 31, 2025, compared to the same period in 2024, the increase in our effective tax rate was partially driven by the impacts of certain share-based compensation awards that vested during the first quarter of 2025 and the changes in the territorial mix of our profitability. This is partially offset by benefits related to a decrease in our foreign valuation allowance and our estimate of our Pillar Two minimum tax liabilities, both of which are included in our taxes on foreign earnings, including valuation allowance.

Accounting for Uncertainty in Income Taxes

We and our subsidiaries are routinely examined by various taxing authorities. We file income tax returns in various U.S. states and in U.S. federal and other foreign jurisdictions. With few exceptions, we are no longer subject to U.S. federal tax examination for years before 2021 or state, local or non-U.S. income tax examinations for years before 2013.

The U.S. Internal Revenue Service and other national tax authorities routinely examine our intercompany transfer pricing with respect to intellectual property related transactions and it is possible that they may disagree with one or more positions we have taken with respect to such valuations.

It is reasonably possible that we will adjust the value of our uncertain tax positions related to certain transfer pricing, collaboration matters, withholding taxes and other issues as we receive additional information from various taxing authorities, including reaching settlements with such authorities.

We estimate that it is reasonably possible that our gross unrecognized tax benefits, exclusive of interest, could

decrease by up to approximately $40.0 million in the next 12 months as a result of various audit closures, settlements and expiration of the statute of limitations.

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Note 18:			Other Consolidated Financial Statement Detail

Other (Income) Expense, Net

Components of other (income) expense, net, are summarized as follows:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Interest income						$	(23.9)					$	(17.4)
Interest expense						60.0						69.2
(Gains) losses on investments, net						35.6						30.6
Foreign exchange (gains) losses, net						(3.8)						9.4
Other, net						0.5						1.9
Total other (income) expense, net						$	68.4					$	93.7

The (gains) losses on investments, net, as reflected in the table above, relate to equity securities of certain biotechnology companies, venture capital funds where the underlying investments are in equity securities of certain biotechnology companies and non-marketable equity securities.

The following table summarizes our (gains) losses on investments, net that relate to our equity securities held during the following periods:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Net (gains) losses recognized on equity securities						$	35.6					$	30.6
Less: Net (gains) losses realized on equity securities						(5.4)						4.9
Net unrealized (gains) losses recognized on equity securities						$	41.0					$	25.7

The net unrealized losses recognized during the three months ended March 31, 2025, primarily reflect a decrease in the aggregate fair value of our investments in Denali common stock of approximately $48.5 million, partially offset by an increase in the fair value of Sage common stock of approximately $15.7 million.

The net unrealized losses recognized during the three months ended March 31, 2024, primarily reflect a decrease in the aggregate fair value of our investments in Sage and Denali common stock of approximately $27.7 million, partially offset by an increase in the fair value of Sangamo common stock of approximately $1.4 million.

Accrued Expense and Other

Accrued expense and other consists of the following:

(In millions)						As of March 31, 2025						As of December 31, 2024
Revenue-related reserves for discounts and allowances						$	965.2					$	937.5
Employee compensation and benefits						192.3						375.8
Collaboration expense						233.1						309.0
Royalties and licensing fees						166.9						190.2
Current portion of contingent consideration obligations						294.3						291.2
Other						678.9						704.0
Total accrued expense and other						$	2,530.7					$	2,807.7

Other Long-term Liabilities

Other long-term liabilities were $751.7 million and $732.3 million as of March 31, 2025 and December 31, 2024, respectively, and included accrued income taxes totaling $162.1 million and $156.7 million, respectively.

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Note 19:			Collaborative and Other Relationships

Genentech, Inc. (Roche Group)

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 for the treatment of relapsed or refractory follicular lymphoma; COLUMVI, a bispecific antibody for the 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. For purposes of this footnote, we refer to RITUXAN and RITUXAN HYCELA collectively as RITUXAN.

RITUXAN

Genentech and its affiliates are responsible for the worldwide manufacture of RITUXAN as well as all development and commercialization activities as follows:

*•*U.S.: We have co-exclusively licensed our rights to develop, commercialize and market RITUXAN in the U.S.

*•*Canada: We have co-exclusively licensed our rights to develop, commercialize and market RITUXAN in Canada.

GAZYVA

The Roche Group and its sub-licensees maintain sole responsibility for the development, manufacture and commercialization of GAZYVA in the U.S. The level of gross sales of GAZYVA in the U.S. has impacted our percentage of the co-promotion profits for RITUXAN and LUNSUMIO, as summarized in the table below.

OCREVUS

Pursuant to the terms of our collaboration arrangements with Genentech, we receive a tiered royalty on U.S. net sales from 13.5% and increasing up to 24.0% if annual net sales exceed $900.0 million. There will be a 50.0% reduction to these royalties upon the first entry of an FDA approved biosimilar to OCREVUS.

In addition, we receive a gross 3.0% royalty on net sales of OCREVUS outside the U.S., with the royalty period lasting 11 years from the first commercial sale of OCREVUS on a country-by-country basis.

The commercialization of OCREVUS does not impact the percentage of the co-promotion profits we receive for RITUXAN, LUNSUMIO or GAZYVA. Genentech is solely responsible for development and commercialization of OCREVUS and funding future costs. Genentech cannot develop OCREVUS in CLL, non-Hodgkin's lymphoma or rheumatoid arthritis.

OCREVUS royalty revenue is based on our estimates from third party and market research data of OCREVUS sales occurring during the corresponding period. Differences between actual and estimated royalty revenue will be adjusted for in the period in which they become known, which is generally expected to be the following quarter.

LUNSUMIO

We are entitled to a tiered share of co-promotion operating profits and losses in the U.S., as summarized in the table below. In addition, we receive low-single digit royalties on sales of LUNSUMIO outside the U.S.

COLUMVI

Genentech has sole decision-making rights on the commercialization of COLUMVI within the U.S. and we receive tiered royalties in the mid-single digit range on net sales of COLUMVI in the U.S. Under the terms of this agreement, we have no payment obligations. The commercialization of COLUMVI does not impact the percentage of the co-promotion profits we receive for RITUXAN, LUNSUMIO or GAZYVA.

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Profit-sharing Formulas

RITUXAN and LUNSUMIO Profit Share

Our current pretax co-promotion profit-sharing formula for RITUXAN and LUNSUMIO in the U.S. provides for a 30.0% share on the first $50.0 million of combined co-promotion operating profits earned each calendar year. As a result of the FDA approval of LUNSUMIO our share of the combined annual co-promotion profits for RITUXAN and LUNSUMIO in excess of $50.0 million varies upon the following events, as summarized in the table below:

After LUNSUMIO Approval until the First Threshold Date			37.5		%
After First Threshold Date until the Second Threshold Date			35.0		%
After Second Threshold Date			30.0		%

First Threshold Date means the earlier of (i) the first day of the calendar quarter following the date U.S. gross sales of GAZYVA within any consecutive 12-month period have reached $500.0 million or (ii) the first date in any calendar year in which U.S. gross sales of LUNSUMIO have reached $150.0 million.

Second Threshold Date means the later of (i) the first date in any calendar year in which U.S. gross sales of LUNSUMIO have reached $350.0 million or (ii) January 1 of the calendar year following the calendar year in which the First Threshold Date occurs.

In March 2023 the First Threshold Date was achieved. As a result, beginning in April 2023 the pre-tax profit share for RITUXAN and LUNSUMIO was 35.0%.

GAZYVA Profit Share

Our current pretax profit-sharing formula for GAZYVA provides for a 35.0% share on the first $50.0 million of operating profits earned each calendar year. Our share of annual co-promotion profits in excess of $50.0 million varies upon the following events, as summarized in the table below:

Until Second GAZYVA Threshold Date			37.5		%
After Second GAZYVA Threshold Date			35.0		%

Second GAZYVA Threshold Date means the first day of the calendar quarter following the date U.S. gross sales of GAZYVA within any consecutive 12-month period have reached $500.0 million. The Second GAZYVA Threshold Date can be achieved regardless of whether GAZYVA has been approved in a non-CLL indication.

In March 2023 the Second GAZYVA Threshold Date was achieved. As a result, beginning in April 2023 the pre-tax profit share for GAZYVA was 35.0%.

For additional information on our collaboration arrangements with Genentech, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in our 2024 Form 10-K.

Eisai Co., Ltd.

LEQEMBI (lecanemab) Collaboration

We have a collaboration agreement with Eisai to jointly develop and commercialize LEQEMBI (lecanemab), an anti-amyloid antibody for the treatment of Alzheimer's disease (the LEQEMBI Collaboration).

Eisai serves as the lead of LEQEMBI development and regulatory submissions globally with both companies co-commercializing and co-promoting the product, and Eisai having final decision-making authority. All costs, including research, development, sales and marketing expense, are shared equally between us and Eisai. We and Eisai co-promote LEQEMBI and share profits and losses equally. We currently have a supply agreement with Eisai to manufacture LEQEMBI drug substance and drug product through the end of 2031.

In July 2023 the FDA granted traditional approval of LEQEMBI. Prior to receiving traditional approval, LEQEMBI had been granted accelerated approval by the FDA in January 2023, at which time it became commercially available in the U.S. Outside of the U.S., LEQEMBI is now approved in the E.U. (April 2025), China (January 2024), Japan (September 2023) and other international markets. Additionally, in January 2025 the FDA approved LEQEMBI monthly IV maintenance dosing for the treatment of early Alzheimer's disease.

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Upon commercialization of LEQEMBI in the U.S., we began recognizing our 50.0% share of LEQEMBI product revenue, net and cost of sales, including royalties, within Alzheimer's collaboration revenue in our condensed consolidated statements of income, as we are not the principal.

Our share of LEQEMBI sales and marketing expense and development expense are recorded within selling, general and administrative expense and research and development expense, respectively, within our condensed consolidated statements of income.

A summary of development and sales and marketing expense related to the LEQEMBI Collaboration is as follows:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Total development expense incurred by the collaboration related to the advancement of LEQEMBI						$	52.6					$	87.3
Biogen's share of the LEQEMBI Collaboration development expense reflected in research and development expense in our condensed consolidated statements of income						26.3						43.6
Total sales and marketing expense incurred by the LEQEMBI Collaboration						177.7						173.9
Biogen's share of the LEQEMBI Collaboration sales and marketing expense reflected in selling, general and administrative expense in our condensed consolidated statements of income						88.8						86.9

Amounts receivable from Eisai related to the agreements discussed above were approximately $115.5 million and $16.7 million as of March 31, 2025 and December 31, 2024, respectively. Amounts payable to Eisai related to the agreements discussed above were approximately $122.6 million and $138.0 million as of March 31, 2025 and December 31, 2024, respectively.

For additional information on our collaboration arrangements with Eisai, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in our 2024 Form 10-K.

UCB

We have a collaboration agreement with UCB, effective November 2003, to jointly develop and commercialize dapirolizumab pegol, an anti-CD40L pegylated Fab, for the potential treatment of SLE and other future agreed indications. Either we or UCB may propose development of dapirolizumab pegol in additional indications. If the parties do not agree to add an indication as an agreed indication to the collaboration, we or UCB may, at the sole expense of the applicable party, pursue development in such excluded indication(s), subject to an opt-in right of the non-pursuing party after proof of clinical activity.

All costs incurred for agreed indications, including research, development, sales and marketing expense, are shared equally between us and UCB. If marketing approval is obtained, both companies will jointly commercialize dapirolizumab pegol and share profits and losses equally.

A summary of development expense related to the UCB collaboration agreement is as follows:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Total UCB collaboration development expense						$	21.8					$	16.6
Biogen's share of UCB collaboration development expense reflected in research and development expense in our condensed consolidated statements of income						10.9						8.3

Sage Therapeutics, Inc.

In November 2020 we entered into a global collaboration and license agreement with Sage to jointly develop and commercialize ZURZUVAE (zuranolone) for the treatment of PPD and potential treatment of MDD and BIIB124 (SAGE-324) for the potential treatment of essential tremor with potential in other neurological conditions such as epilepsy. In July 2024 we and Sage announced that the Phase 2 KINETIC 2 dose-range study of BIIB124 did not meet its endpoints. Based on these results, we discontinued our further development of BIIB124 and terminated our rights under the collaboration and license agreement specific to BIIB124, effective February 17, 2025.

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In August 2023 the FDA approved ZURZUVAE for adults with PPD, pending DEA scheduling, which was completed in October 2023. Upon approval, ZURZUVAE 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. In October 2024 we and Sage agreed to not pursue further development of zuranolone for the potential treatment of MDD. This decision was based on the significant new investment and time we expect would be needed to conduct the additional studies required to support approval of this indication.

Under this collaboration, both companies will share equal responsibility and costs for development as well as profits and losses for commercialization in the U.S. Outside of the U.S., we are responsible for development and commercialization, excluding Japan, Taiwan and South Korea, with respect to zuranolone and may pay Sage potential tiered royalties in the high teens to low twenties. During the fourth quarter of 2023 we accrued a milestone payment due to Sage of $75.0 million upon the first commercial sale of ZURZUVAE for PPD in the U.S., which was recorded within intangible assets, net in our condensed consolidated balance sheets, and subsequently paid in January 2024.

For the three months ended March 31, 2025 and 2024, we recognized net profit-sharing expense of approximately $10.1 million and $5.0 million, respectively, to reflect Sage's 50.0% share of net collaboration results in the U.S., which are recognized in collaboration profit sharing/(loss reimbursement) in our condensed consolidated statements of income.

A summary of development and sales and marketing expense related to the Sage collaboration is as follows:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Total Sage collaboration development expense						$	2.4					$	11.6
Biogen's share of Sage collaboration development expense reflected in research and development expense in our condensed consolidated statements of income						1.2						5.8
Total sales and marketing expense incurred by the Sage collaboration						43.5						27.6
Biogen's share of Sage collaboration sales and marketing expense reflected in selling, general and administrative expense and collaboration profit sharing/(loss reimbursement) in our condensed consolidated statements of income						21.7						13.8

Denali Therapeutics Inc.

In August 2020 we entered into a collaboration and license agreement with Denali to co-develop and co-commercialize BIIB122, a small molecule inhibitor of LRRK2 for Parkinson's disease (LRRK2 Collaboration).

Under the LRRK2 Collaboration, both companies share responsibility and costs for global development based on specified percentages as well as profits and losses for commercialization in the U.S. and China. Outside the U.S. and China we are responsible for commercialization and may pay Denali potential tiered royalties.

A summary of development expense related to the Denali collaboration is as follows:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Total Denali collaboration development expense						$	12.8					$	14.2
Biogen's share of Denali collaboration development expense reflected in research and development expense in our condensed consolidated statements of income						7.7						8.5

Stoke Therapeutics, Inc.

In February 2025 we entered into a collaboration and license agreement with Stoke to co-develop and commercialize zorevunersen, an investigational ASO that targets the SCN1A gene for the potential treatment of Dravet syndrome, a rare form of genetic epilepsy associated with refractory seizures and neurodevelopmental impairments.

Under the terms of this agreement, Stoke will continue to lead global development and retain exclusive development and commercialization rights for zorevunersen in the U.S., Canada and Mexico and we will have exclusive rights to commercialize zorevunersen in the rest of the world. Both companies will share responsibility for external clinical development costs, where Stoke is responsible for 70.0% of these development costs and we are responsible for the remaining 30.0% of these development costs.

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In connection with the closing of this transaction we made an upfront payment of $165.0 million to Stoke, which was recognized as acquired in-process research and development, upfront and milestone expense within our condensed consolidated statements of income for the three months ended March 31, 2025. We may also pay Stoke development and commercial milestone payments that could total up to approximately $50.0 million and $335.0 million, respectively, if all the specified milestones set forth in this collaboration are achieved. In addition, we may pay Stoke tiered royalties on potential net sales of any products developed under this collaboration in the low double-digit to high teen percentages.

We also have an exclusive option to license certain future follow-on ASO products targeting the SCN1A gene in all territories worldwide other than the U.S., Canada and Mexico, in exchange for separate milestone, cost sharing and royalty considerations.

A summary of development expense related to the Stoke collaboration agreement is as follows:

(In millions)						For the Three Months Ended March 31, 2025
Total Stoke collaboration development expense						$	3.9
Biogen's share of Stoke collaboration development expense reflected in research and development expense in our condensed consolidated statements of income						1.2

Other Research and Discovery Arrangements and Funding Arrangements

These arrangements may include the potential for future milestone payments based on the achievement of certain clinical and commercial development payable over a period of several years.

Royalty Pharma Funding Arrangement

In February 2025 we entered into a funding agreement with Royalty Pharma under which we will receive up to $200.0 million in 2025 and up to $50.0 million in 2026 to co-fund our development costs for the litifilimab program. As there is a substantive transfer of risk to the financial partner for the amount invested, the development funding will be recognized by us as an obligation to perform contractual services. We plan to recognize this funding as a reduction to research and development expense within our condensed consolidated statements of income, proportionate to the related expenses. For the three months ended March 31, 2025, we recorded a $50.0 million reduction to research and development expense within our condensed consolidated statements of income.

If the litifilimab clinical trials are successful for the indications based on the applicable clinical trials, upon regulatory approval in the U.S. or certain major markets in the world, Royalty Pharma will be eligible to receive approval-based fixed milestone payments of up to a total of $250.0 million. The milestone payments due upon approval will be recorded as a component of other (income) expense, net within our condensed consolidated statements of income, when incurred.

If litifilimab receives regulatory approval, Royalty Pharma will be eligible to royalties of a mid-single digits percentage of the applicable net sales. Royalties on net sales will be recorded as cost of sales within our condensed consolidated statements of income.

MorphoSys AG

As part of our acquisition of HI-Bio, we acquired HI-Bio's pre-existing in-license commitments under third-party agreements with MorphoSys, which include tiered royalties on potential future sales of felzartamab and izastobart/HIB210, ranging from high-single digit to mid-teen percentages, as well as potential development, regulatory and commercial milestone payments related to felzartamab and izastobart/HIB210 of up to $130.0 million, $230.0 million and $640.0 million, respectively. This amount includes milestone payments due upon the first patient dosed in a Phase 3 clinical trial of felzartamab in a first and second indication of $35.0 million and $30.0 million, respectively. During the first quarter of 2025 we accrued a milestone payment due to MorphoSys of $35.0 million upon the first patient dosed in a Phase 3 clinical trial of felzartamab for the treatment of AMR, which was recorded within acquired in-process research and development, upfront and milestone expense in our condensed consolidated statements of income for the three months ended March 31, 2025, and subsequently paid in April 2025.

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Samsung Bioepis Co., Ltd.

2019 Development and Commercialization Agreement

In December 2019 we completed a transaction with Samsung Bioepis and secured the exclusive rights to commercialize two potential ophthalmology biosimilar products, BYOOVIZ, a ranibizumab biosimilar referencing LUCENTIS, and OPUVIZ, an aflibercept biosimilar referencing EYLEA, in major markets worldwide, including the U.S., Canada, Europe, Japan and Australia. The agreement established that Samsung Bioepis will be responsible for development and will supply both products to us at a pre-specified gross margin of approximately 45.0%.

In October 2024 we notified Samsung Bioepis of our decision to terminate our 2019 Development and Commercialization Agreement (the DCA Agreement) solely within the U.S. and Canada. As a result of this termination we recognized impairment charges of approximately $20.2 million, which were recorded within amortization and impairment of acquired intangible assets within our consolidated statements of income for the year ended December 31, 2024, included in our 2024 Form 10-K. Biogen will transfer commercialization rights for BYOOVIZ and OPUVIZ in the U.S. and Canada back to Samsung Bioepis over a period of up to 18 months. During this transition period, we will continue to commercialize BYOOVIZ. The termination does not impact the other markets in the DCA Agreement.

In the fourth quarter of 2024 we made a milestone payment of $15.0 million to Samsung Bioepis related to the approval of OPUVIZ in the E.U., which was recorded within intangible assets, net in our condensed consolidated balance sheets. We may also pay Samsung Bioepis up to approximately $150.0 million in additional sales-based milestones associated with the remaining major markets covered by the agreement.

2013 Commercial Agreement

In December 2013 we entered into an agreement with Samsung Bioepis to commercialize, over a 10-year term, three anti-TNF biosimilar product candidates which includes IMRALDI, an adalimumab biosimilar referencing HUMIRA, FLIXABI, an infliximab biosimilar referencing REMICADE, and BENEPALI, an etanercept biosimilar referencing ENBREL, in Europe.

In July 2024 we exercised an option to extend this agreement by an additional five years, and paid Samsung Bioepis an option exercise fee of $60.0 million, which was recognized in intangible assets, net within our condensed consolidated balance sheets as of December 31, 2024.

We reflect revenue on sales of BENEPALI, IMRALDI and FLIXABI to third parties in product revenue, net in our condensed consolidated statements of income and record the related cost of revenue and sales and marketing expense in our condensed consolidated statements of income to their respective line items when these costs are incurred. Royalty payments to AbbVie on sales of IMRALDI are recognized in cost of sales within our condensed consolidated statements of income.

We share 50.0% of the profit or loss related to our 2013 commercial agreement with Samsung Bioepis, which is recognized in collaboration profit sharing/(loss reimbursement) in our condensed consolidated statements of income. For the three months ended March 31, 2025 and 2024, we recognized net profit-sharing expense of approximately $48.0 million and $60.6 million, respectively, to reflect Samsung Bioepis' 50.0% sharing of the net collaboration profits.

Other Services

Simultaneous with the formation of Samsung Bioepis, we also entered into a license agreement with Samsung Bioepis. Under this license agreement, we granted Samsung Bioepis an exclusive license to use, develop, manufacture and commercialize biosimilar products created by Samsung Bioepis using Biogen product-specific technology. In exchange, we receive single-digit royalties on biosimilar products developed and commercialized by Samsung Bioepis. Royalty revenue under the license agreement is recognized as a component of contract manufacturing, royalty and other revenue in our condensed consolidated statements of income.

Amounts receivable from Samsung Bioepis related to the agreements discussed above were approximately $3.9 million and $7.6 million as of March 31, 2025 and December 31, 2024, respectively. Amounts payable to Samsung Bioepis related to the agreements discussed above were approximately $72.9 million and $60.8 million as of March 31, 2025 and December 31, 2024, respectively.

For additional information on our collaboration arrangements with Samsung Bioepis and our other significant collaboration arrangements, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in our 2024 Form 10-K.

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(unaudited, continued)

Note 20:			Investments in Variable Interest Entities

Unconsolidated Variable Interest Entities

We have relationships with various variable interest entities that we do not consolidate as we lack the power to direct the activities that significantly impact the economic success of these entities. These relationships include investments in certain biotechnology companies and research collaboration agreements.

As of March 31, 2025 and December 31, 2024, the carrying value of our investments in certain biotechnology companies representing potential unconsolidated variable interest entities totaled $19.3 million and $23.6 million, respectively. Our maximum exposure to loss related to these variable interest entities is limited to the carrying value of our investments.

We have also entered into research collaboration agreements with certain variable interest entities where we are required to fund certain development activities. These development activities are included in research and development expense in our condensed consolidated statements of income as they are incurred. We have provided no financing to these variable interest entities other than previous contractually required amounts.

For additional information on our investments in variable interest entities, please read Note 20, Investments in Variable Interest Entities, to our consolidated financial statements included in our 2024 Form 10-K.

Note 21:			Litigation

We are currently involved in various claims, investigations and legal proceedings, including the matters described below. For information as to our accounting policies relating to claims and legal proceedings, including use of estimates and contingencies, please read Note 1, Summary of Significant Accounting Policies, to our consolidated financial statements included in our 2024 Form 10-K.

With respect to some loss contingencies, an estimate of the possible loss or range of loss cannot be made until management has further information, including, for example, (i) which claims, if any, will survive dispositive motion practice; (ii) information to be obtained through discovery; (iii) information as to the parties' damages claims and supporting evidence; (iv) the parties’ legal theories; and (v) the parties' settlement positions. If an estimate of the possible loss or range of loss can be made at this time, it is included in the potential loss contingency description below.

The claims and legal proceedings in which we are involved also include challenges to the scope, validity or enforceability of the patents relating to our products, pipeline or processes and challenges to the scope, validity or enforceability of the patents held by others. These include claims by third parties that we infringe their patents. An adverse outcome in any of these proceedings could result in one or more of the following and have a material impact on our business or consolidated results of operations and financial position: (i) loss of patent protection; (ii) inability to continue to engage in certain activities; and (iii) payment of significant damages, royalties, penalties and/or license fees to third parties.

Loss Contingencies

Securities Litigation asserted against Biogen

We and certain current and former officers are defendants in three securities actions pending in the District Court, one filed by Nadia Shash and Amjad Khan in November 2020, which relates to statements about ADUHELM, one filed by the Oklahoma Firefighters Pension and Retirement System in February 2022, which relates to statements about ADUHELM, and one filed by Thomas Allen Gray in June 2024, which relates to statements about LEQEMBI, TECFIDERA and VUMERITY. All allege violations of federal securities laws under 15 U.S.C. §78j(b) and §78t(a) and 17 C.F.R. §240.10b-5 and seek declarations of the actions as class actions and monetary relief.

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Derivative Actions

We and members of the Board of Directors are named as defendants in five derivative actions pending in the District Court, one filed by The Booth Family Trust in February 2022, one filed by Elaine Wang in July 2022, one filed by Jonathan Blaufarb (Blaufarb I) in July 2024, one filed by Lawrence Hollin in October 2024 and one filed by Jonathan Blaufarb (Blaufarb II) in October 2024. The Booth, Wang and Blaufarb II actions relate to ADUHELM and other matters, and the Blaufarb I and Hollin actions relate to statements about LEQEMBI, our compliance controls, 2023 earnings guidance and other matters. The actions allege breach of fiduciary duty, waste of corporate assets and other common law claims, and violations of the Securities Exchange Act of 1934, 15 U.S.C. §78a et seq. The actions seek declaratory and injunctive relief, monetary relief payable to Biogen, and attorneys’ fees and costs payable to the plaintiffs. All derivative actions are stayed.

IMRALDI Patent Litigation

In June 2022 Fresenius Kabi filed a claim for damages and injunctive relief against Biogen France SAS in the Tribunal de Grande Instance de Paris alleging that IMRALDI, the adalimumab biosimilar product of Samsung Bioepis that Biogen commercializes in Europe, infringes the French counterpart of the EP ‘488 Patent. In March 2024 the Düsseldorf Regional Court dismissed Fresenius Kabi's claim of infringement of the German counterpart of the EP '488 Patent and Fresenius Kabi has appealed to the Higher Regional Court of Düsseldorf and a decision is pending.

Litigation with Former Convergence Shareholders

In 2015 Biogen acquired Convergence, a U.K. company. In 2019 Shareholder Representative Services LLC, on behalf of the former shareholders of Convergence, asserted claims of $200.0 million for alleged breaches of the contract pursuant to which we acquired Convergence. In June 2023 Shareholder Representative Services LLC and 24 former shareholders filed a suit against us in the High Court of Justice of England and Wales asserting one of the 2019 claims and seeking payment of $49.9 million, interest and costs. Trial is scheduled for the second quarter of 2025.

Humana Patient Assistance Litigation

In February 2025 Humana filed suit against Biogen Inc., Biogen U.S. Corp. and Advanced Care Scripts, Inc. in Jefferson Circuit Court in Kentucky alleging damages related to our providing MS patients with free medications and making charitable contributions to non-profit organizations that assist MS patients. Humana alleges breach of contract, fraud and other claims under various state laws and seeks damages, attorneys' fees and costs.

Genentech Litigation

In February 2023 Genentech, Inc. filed suit against us in the U.S. District Court for the Northern District of California and claims that it is owed royalties of approximately $92.7 million on sales of TYSABRI that occurred after the expiration of a patent licensed by Genentech to Biogen, plus interest and costs. Trial is scheduled to begin in the second quarter of 2025.

Lender Litigation

In April 2025, by agreement of the parties, the court discontinued with prejudice the previously disclosed suit filed in 2024 by BioPharma Credit PLC, BPCR Limited Partnership, and BioPharma Credit Investments V (Master) LP against us and Reata Pharmaceuticals, Inc. in the Supreme Court of the State of New York alleging breach of a loan agreement with Reata.

Antitrust Litigation

In August 2024 we were sued by Local No. 1 Health Fund and in September 2024 we were sued by the Mayor and City Council of Baltimore, New York State Teamsters Council Health and Hospital Fund, Teamsters Local 237 Welfare Fund and Teamsters Local 237 Retirees' Benefit Fund, in cases filed in the U.S. District Court for the Northern District of Illinois. After the cases were consolidated for pre-trial purposes, UFCW Local 1500 Welfare Fund sued us along with these plaintiffs in a consolidated amended complaint filed in November 2024. The plaintiffs allege violations of federal antitrust laws including 15 U.S.C. §§ 1, 2 and 13(c) and of various state laws, based on contracts with pharmacy benefit managers related to TECFIDERA and VUMERITY. Plaintiffs seek declarations of the actions as class actions, monetary, declaratory and equitable relief, and attorneys' fees and costs.

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Other Matters

Government Investigations

In April 2025 the SEC Division of Enforcement informed us that it has closed the matter in which we had received subpoenas seeking information relating to ADUHELM and its launch and our equity plans, and in April 2025 the DOJ informed us that it has closed the matter in which we had received subpoenas seeking information relating to our business operations in several foreign countries.

As previously disclosed, we have received subpoenas from the SEC seeking information relating to our business operations in several foreign countries.

The Italian Competition Authority is investigating Biogen and other companies in relation to our biosimilar product BYOOVIZ.

TYSABRI Biosimilar Patent Matter

In September 2022 we filed an action in the U.S. District Court for the District of Delaware against Sandoz Inc., other Sandoz entities and Polpharma Biologics S.A. under the Biologics Price Competition and Innovation Act, 42 U.S.C. §262, seeking a declaratory judgment of patent infringement. Trial is scheduled for the second quarter of 2025.

Hatch-Waxman Act Litigation relating to VUMERITY Orange-Book Listed Patents

In July 2023 Biogen and Alkermes Pharma Ireland Limited filed patent infringement proceedings relating to VUMERITY Orange-Book listed patents (U.S. Patent Nos. 8,669,281, 9,090,558 and 10,080,733) pursuant to the Drug Price Competition and Patent Term Restoration Act of 1984 (the Hatch-Waxman Act) in the U.S. District Court for the District of Delaware against Zydus Worldwide DMCC, Zydus Pharmaceuticals (USA) Inc. and Zydus Lifesciences Limited. Trial is scheduled for the third quarter of 2025.

Product Liability and Other Legal Proceedings

We are also involved in product liability claims and other legal proceedings incidental to our normal business activities. While the outcome of any of these proceedings cannot be accurately predicted, we do not believe the ultimate resolution of any of these existing matters would have a material adverse effect on our business or financial condition.

Note 22:			Segment Information

We operate and are managed as one operating segment, and derive revenue from activities related to the discovery, development and delivery of innovative therapies for people living with serious and complex diseases.

Our research and development organization is responsible for the research and discovery of new product candidates and supports development and registration efforts for potential future products. Our pharmaceutical, operations and technology organization manages the development of the manufacturing processes, clinical trial supply, commercial product supply, distribution, buildings and facilities. Our commercial organization is responsible for U.S. and international development of our commercial products. We are also supported by corporate staff functions.

Our CEO, as the CODM, manages and allocates resources to the operations of our company on a total company basis by assessing the overall level of resources available and deciding how to best deploy these resources across functions, therapeutic areas and research and development projects that are in line with our long-term company-wide strategic goals. In making these decisions, our CEO is provided with and uses consolidated financial information for purposes of evaluating performance, forecasting future period financial results, allocating resources and setting incentive targets. The CODM performs this assessment based on the segment’s net income. Through this analysis, which includes a comparison to budgeted results, the CODM assesses performance and how to allocate resources across the functions discussed above. The measure of segment assets used in determining how to manage and allocate resources is reported within our condensed consolidated balance sheets as total assets.

The table presented below, which was prepared in accordance with the accounting policies discussed in Note 1, Summary of Significant Accounting Policies, to our consolidated financial statements included in our 2024 Form 10-K, contains additional information on enterprise-wide disclosures about product revenue, other revenue and long-lived assets, as well as our segment’s revenue and profits, including significant segment expense and other segment items. Revenue is primarily attributed to individual countries based on location of the customer or licensee.

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Additional Segment Information

The following table includes additional information about reported segment revenue, significant segment expense and segment measure of profitability:

						For the Three Months Ended March 31,
(In millions)						2025						2024
Total revenue						$	2,431.0					$	2,290.5
Less cost and expense:
Cost of sales, excluding amortization and impairment of acquired intangible assets:
Product cost of sales						462.2						377.7
Royalty cost of sales						167.1						164.5
Research and development:
Research and discovery						44.3						47.6
Early stage programs						72.4						84.1
Late stage programs						49.4						32.6
Marketed products						89.5						118.1
Other research and development costs(1)						178.5						163.0
Acquired in-process research and development, upfront and milestone expense						200.7						7.5
Selling, general and administrative						572.5						581.5
Other segment expense(2)						353.9						320.5
Net Income attributable to Biogen Inc.						$	240.5					$	393.4

(1) Other research and development costs primarily consist of indirect costs incurred in support of overall research and development activities and non-specific programs, including activities that benefit multiple programs, such as management costs, as well as depreciation, information technology and facility-based expenses and are not allocated to a specific program or stage.

(2) Other segment expense includes: amortization and impairment of acquired intangible assets; collaboration profit sharing/(loss reimbursement); (gain) loss on fair value remeasurement of contingent consideration; restructuring charges; other (income) expense, net; and income tax (benefit) expense.

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