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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~~June 3130, 2026


☐			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

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~~July 27, 2026, was 147,~~637~~753,~~117~~998 shares.

Table of Contents

BIOGEN INC.

FORM 10-Q — Quarterly Report

For the Quarterly Period Ended ~~March~~June 3130, 2026

TABLE OF CONTENTS

		Page
PART I — FINANCIAL INFORMATION
Item 1.	Financial Statements (unaudited)
	Condensed Consolidated Statements of Income — For the Three Months Ended March 31, 2026 and 2025	8
	Condensed Consolidated Statements of Income — For the Three and Six Months Ended June 30, 2026 and 2025	8
	Condensed Consolidated Statements of Comprehensive Income — For the Three Months Ended March 31, 2026 and 2025	9
	Condensed Consolidated Statements of Comprehensive Income — For the Three and Six Months Ended June 30, 2026 and 2025	9
	Condensed Consolidated Balance Sheets — As of March 31, 2026 and December 31, 2025	10
	Condensed Consolidated Balance Sheets — As of June 30, 2026 and December 31, 2025	10
	Condensed Consolidated Statements of Cash Flow — For the Three Months Ended March 31, 2026 and 2025	11
	Condensed Consolidated Statements of Cash Flow — For the Six Months Ended June 30, 2026 and 2025	11
	Condensed Consolidated Statements of Equity — For the Three Months Ended March 31, 2026 and 2025	12
	Condensed Consolidated Statements of Equity — For the Three and Six Months Ended June 30, 2026 and 2025	12
	Notes to Condensed Consolidated Financial Statements	1314
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	4351
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	6781
Item 4.	Controls and Procedures	6983
PART II — OTHER INFORMATION
Item 1.	Legal Proceedings	7084
Item 1A.	Risk Factors	7084
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	86100
Item 5.	Other Information	86100
Item 6.	Exhibits	87101
Signatures		88102

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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,” "seek," “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, prospects and the timing of actions 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 and uncertainties, 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 exclusivities, as well as our ability to adequately enforce existing patents;

•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~~litifilimab;

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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, HI-Bio, Alcyone and ~~the potential acquisition of~~ Apellis, including future performance of the SKYCLARYS, EMPAVELI and SYFOVRE products, ~~further~~ development of the felzartamab product, future development of drug delivery solutions 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;

•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 Supernus, as well as the potential therapeutic scope of the development and commercialization of our and our collaborators’ pipeline products;

•the impacts of disruptions, turnover or changes in strategy, priorities or capabilities at our collaborators resulting from, for example, a change in control, and the related impacts on the commercialization or manufacturing of our shared 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 (or other legislative or executive acts that may modify or replace the IRA, such as the OBBBA) 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 continued and potential future impact of legislative and regulatory changes and priorities, including actions related to the MFN drug pricing policy;

•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,

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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;

•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 Part II, Item 1A. Risk Factors and Part I, 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 2025 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®, EMPAVELI®, PLEGRIDY®, QALSODY®, RITUXAN®, RITUXAN HYCELA®, SKYCLARYS®, SPINRAZA®, SYFOVRE®, TECFIDERA®, THECAFLEX DRX®, TYSABRI® and VUMERITY® are registered trademarks of Biogen.

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

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

NOTE REGARDING DISCLOSURES

From time to time, we have used, or expect in the future to use, our investor relations website (investors.biogen.com), the Biogen LinkedIn account (linkedin.com/company/biogen/-) and the Biogen X account (https://x.com/biogen) as a means of disclosing information to the public in a broad, non-exclusionary manner, including for purposes of the SEC’s Regulation Fair Disclosure (Reg FD). Accordingly, investors should monitor our investor relations website and these social media channels in addition to our press releases, SEC filings, public conference calls and websites, as the information posted on them could be material to investors.

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DEFINED TERMS

2025 Form 10-K			Annual Report on Form 10-K for the year ended December 31, 2025
2020 Share Repurchase Program			Board of Directors authorized program to repurchase up to $5.0 billion of our common stock
2023 Term Loan			$1.5 billion term loan credit agreement
2026 Term Loan			$2.0 billion term loan credit agreement
2025 Senior Notes			Senior Unsecured Notes Issued in May 2025
AbbVie			AbbVie Inc.
AI			Artificial Intelligence
Alcyone			Alcyone Therapeutics, Inc.
Alloy			Alloy Therapeutics, Inc.
ALS			Amyotrophic Lateral Sclerosis
Alteogen			Alteogen Inc.
AMR			Antibody-Mediated Rejection
AOCI			Accumulated Other Comprehensive Income (Loss)
Apellis			Apellis Pharmaceuticals, Inc.
ASO			Antisense Oligonucleotide
ASU			Accounting Standards Update
BLA			Biologics License Application
C3G			C3 Glomerulopathy
CCPA			California Consumer Privacy Act
CLE			Cutaneous Lupus Erythematosus
CLL			Chronic Lymphocytic Leukemia
CMS			Centers for Medicare & Medicaid Services
CNS			Central Nervous System
CODM			Chief Operating Decision Maker
CROs			Contract Research Organizations
CVR			Contingent Value Right
Denali			Denali Therapeutics Inc.
District Court			U.S. District Court for the District of Massachusetts
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
GA			Geographic Atrophy
Genentech			Genentech, Inc.
GloBE			Global Anti-Base Erosion
GMP			Good Manufacturing Practices
GPO			Group Purchasing Organization
HHS			U.S. Department of Health and Human Services
HI-Bio			Human Immunology Biosciences, Inc.
Humana			Humana Inc.
IC-MPGN			Immune Complex Membranoproliferative Glomerulonephritis
IEEPA			International Emergency Economic Powers Act
IgAN			Immunoglobulin A Nephropathy
IND			Investigational New Drug
IPR&D			In-process Research and Development

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DEFINED TERMS (continued)

IND			Investigational New Drug
IPR&D			In-process Research and Development
IRA			Inflation Reduction Act of 2022
IT			Information Technology
IV			Intravenous
LEQEMBI Collaboration Agreement			Amended and Restated Collaboration Agreement entered into by Biogen MA Inc. and Eisai Co., Ltd. on October 22, 2017, as amended on March 13, 2022
LRRK2			Leucine-Rich Repeat Kinase 2
MorphoSys			MorphoSys AG
MFN			Most-Favored-Nation
MS			Multiple Sclerosis
NCTI			Net CFC Tested Income, previously known as Global Intangible Low-Taxed Income or GILTI
Neurimmune			Neurimmune SubOne AG
NMPA			National Medical Products Administration
OBBBA			Public Law 119-21, commonly referred to as the One Big Beautiful Bill Act
OECD			Organization for Economic Co-operation and Development
Organon			Organon LLC
PDUFA			Prescription Drug User Fee Act
PHS Act			Public Health Service Act
PMN			Primary Membranous Nephropathy
PNH			Paroxysmal Nocturnal Hemoglobinuria
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
RNAi			RNA interference
RTP			Research Triangle Park
Sage			Sage Therapeutics, Inc.
Samsung Bioepis			Samsung Bioepis Co., Ltd.
SEC			U.S. Securities and Exchange Commission
SG&A			Selling, General and Administrative
SLE			Systemic Lupus Erythematosus
SMA			Spinal Muscular Atrophy
Sobi			Swedish Orphan Biovitrum AB (Publ)
SOD1			Superoxide Dismutase 1
Supernus			Supernus Pharmaceuticals, Inc.
SWISSMEDIC			Swiss Agency for Therapeutic Products
TJ Bio			TJ Biopharma (Hangzhou) Co., Ltd.
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,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
	2026		2025		2026		2025
Revenue:
Product revenue, net	$	1,~~752~~916.34	$	1,~~726~~878.57	$	3,668.7	$	3,605.2
Revenue from anti-CD20 therapeutic programs	~~419~~513.15		~~378~~467.23		932.6		845.5
Alzheimer's collaboration revenue	5963.57		3354.09		123.2		87.9
Contract manufacturing, royalty and other revenue	~~246~~242.94		~~293~~244.36		489.3		537.9
Total revenue	2,~~477~~736.80		2,~~431~~645.05		5,213.8		5,076.5
Cost and expense:
Cost of sales, excluding amortization and impairment of acquired intangible assets	~~661~~776.09		~~629~~605.30		1,437.9		1,234.3
Research and development	~~539~~529.06		~~434~~399.10		1,068.6		833.1
Acquired in-process research and development, upfront and milestone expense	34164.0		~~200~~46.76		198.0		247.3
Selling, general and administrative	~~607~~709.37		~~572~~583.58		1,317.0		1,156.3
Amortization and impairment of acquired intangible assets	~~136~~168.52		~~111~~130.89		304.7		242.7
Collaboration profit sharing/(loss reimbursement)	7468.28		5875.10		143.0		133.1
(Gain) loss on fair value remeasurement of contingent consideration	202.5		913.62		23.0		22.8
Restructuring charges	7165.94		35(0.37)		173.3		34.6
Other (income) expense, net	1918.75		6848.47		38.2		117.1
Total cost and expense	2,~~100~~603.16		21,~~119~~901.85		4,703.7		4,021.3
Income before income tax (benefit) expense	~~377~~132.74		~~311~~744.20		510.1		1,055.2
Income tax (benefit) expense	5834.29		70109.72		93.1		179.9
Net income attributable to Biogen Inc.	$	~~319~~97.5	$	~~240~~634.58	$	417.0	$	875.3
Net income per share:
Basic earnings per share attributable to Biogen Inc.	$	20.1766	$	14.6533	$	2.83	$	5.98
Diluted earnings per share attributable to Biogen Inc.	$	20.1566	$	14.6433	$	2.81	$	5.97
Weighted-average shares used in calculating:
Basic earnings per share attributable to Biogen Inc.	147.27		146.15		147.4		146.3
Diluted earnings per share attributable to Biogen Inc.	148.47		146.67		148.6		146.7

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,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
	2026		2025		2026		2025
Net income attributable to Biogen Inc.	$	~~319~~97.5	$	~~240~~634.58	$	417.0	$	875.3
Other comprehensive income (loss):
Unrealized gains (losses) on securities available for sale, net of tax	(1.8)6		—		(0.2)		—
Unrealized gains (losses) on cash flow hedges, net of tax	5214.68		(57105.8)		67.4		(163.6)
Unrealized gains (losses) on pension benefit obligation, net of tax	(0.53)		0.46		(0.8)		1.0
Currency translation adjustments, net of tax	(83.56)		1941.16		(12.1)		60.7
Total other comprehensive income (loss), net of tax	4112.85		(3863.36)		54.3		(101.9)
Comprehensive income (loss) attributable to Biogen Inc.	$	~~361~~110.30	$	~~202~~571.2	$	471.3	$	773.4

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, 2026		As of December 31, 2025
	As of June 30, 2026		As of December 31, 2025
ASSETS
Current assets:
Cash and cash equivalents	$	31,~~382~~285.70	$	3,008.5
Current portion of marketable securities	~~900.0~~—		807.2
Accounts receivable, net of allowance for doubtful accounts of $3.0 and $3.0, respectively	1,369.2		1,342.4
Accounts receivable, net of allowance for doubtful accounts of $2.9 and $3.0, respectively	1,885.6		1,342.4
Due from anti-CD20 therapeutic programs	~~421~~512.28		524.6
Inventory	12,~~949~~384.03		2,168.1
Other current assets	1,~~168~~238.30		1,123.3
Total current assets	97,~~190~~305.47		8,974.1
Marketable securities	~~465.6~~—		431.9
Property, plant and equipment, net	32,~~017~~994.91		3,055.4
Operating lease assets	~~251~~245.37		265.4
Intangible assets, net	913,~~053~~516.54		9,178.5
Goodwill	6,~~488~~990.78		6,491.1
Deferred tax asset	~~238~~202.21		292.5
Investments and other assets	~~777~~831.58		750.6
Total assets	$	2932,~~483~~086.16	$	29,439.5
LIABILITIES AND EQUITY
Current liabilities:
Taxes payable	$	93.6	$	114.8
Current portion of term loan	$	800.0	$	—
Accounts payable	358.5		432.0
Taxes payable	86.9		114.8
Accrued expense and other	2,546.8		2,802.6
Accounts payable	403.9		432.0
Total current liabilities	2,998.9		3,349.4
Accrued expense and other	2,626.3		2,802.6
Notes payable	6,288.5		6,286.8
Total current liabilities	3,917.1		3,349.4
Deferred tax liability	483.5		507.6
Notes payable and term loan	7,290.3		6,286.8
Long-term operating lease liabilities	273.4		290.4
Deferred tax liability	945.5		507.6
Other long-term liabilities	787.1		748.5
Long-term operating lease liabilities	264.8		290.4
Total liabilities	10,831.4		11,182.7
Other long-term liabilities	820.9		748.5
Total liabilities	13,238.6		11,182.7
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	~~896~~983.70		863.1
Accumulated other comprehensive income (loss)	(~~140~~127.27)		(182.0)
Retained earnings	20,~~872~~969.27		20,552.7
Treasury stock, at cost	(2,977.1)		(2,977.1)
Total equity	18,~~651~~848.70		18,256.8
Total liabilities and equity	$	2932,~~483~~086.16	$	29,439.5

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,
	For the Six Months Ended June 30,
	2026		2025
Cash flow from operating activities:
Net income	$	~~319~~417.50	$	~~240~~875.53
Adjustments to reconcile net income to net cash flow from operating activities:
Depreciation and amortization	~~204~~440.45		~~183~~377.25
Excess and obsolescence charges related to inventory	4.8		7.3
Impairment of intangible assets	—		3.5
Amortization of acquired inventory step-up	107.6		51.4
Excess and obsolescence charges related to inventory	9.9		14.3
Share-based compensation	84.0		81.0
Amortization of acquired inventory step-up	310.4		103.9
Contingent consideration	20.5		9.6
Acquired in-process research and development	100.0		—
Deferred income taxes	23.6		(27.8)
Share-based compensation	161.4		155.9
(Gain) loss on strategic investments	(19.0)		40.9
Contingent consideration	23.0		22.8
Other	28.0		6.7
Deferred income taxes	(4.0)		(59.1)
(Gain) loss on strategic investments	(61.8)		33.2
Other	64.0		16.0
Changes in operating assets and liabilities, net of effects of business acquired:
Accounts receivable	(33166.70)		(~~181~~170.05)
Due from anti-CD20 therapeutic programs	~~103~~11.48		~~70.~~4.2
Inventory	~~116~~191.29		62(27.09)
Accrued expense and other current liabilities	(~~243~~292.29)		(~~300~~318.57)
Income tax assets and liabilities	1832.42		69(534.17)
Other changes in operating assets and liabilities, net	(89143.0)		(5375.5)
Net cash flow provided by (used in) operating activities	~~645~~1,094.54		~~259~~420.32
Cash flow from investing activities:
Purchases of property, plant and equipment	(5192.21)		(3763.17)
Proceeds from sales and maturities of marketable securities	~~625.~~2,140.4		—
Purchases of marketable securities	(~~748~~896.86)		—
Acquired in-process research and development	(35.0)		—
Acquisition of Apellis, net of cash acquired	(5,065.1)		—
Acquired in-process research and development	(135.0)		—
Acquisitions of intangible assets	—		(10.0)
Proceeds from sales of strategic investments	0.5		—
Other	(0.28)		(030.26)
Net cash flow provided by (used in) investing activities	(~~209~~4,048.57)		(47104.3)
Cash flow from financing activities:
Payments related to issuance of stock for share-based compensation arrangements, net	(5549.1)		(2418.32)
Other	11.3		1.3
Proceeds from borrowings, net	2,400.0		1,733.4
Net cash flow provided by (used in) financing activities	(43.8)		(23.0)
Repayments of borrowings	(1,096.7)		(1,750.0)
Net increase (decrease) in cash and cash equivalents	392.2		189.0
Other	(2.0)		0.1
Effect of exchange rate changes on cash and cash equivalents	(18.0)		34.3
Net cash flow provided by (used in) financing activities	1,252.2		(34.7)
Net increase (decrease) in cash and cash equivalents	(1,702.1)		281.2
Effect of exchange rate changes on cash and cash equivalents	(21.4)		102.6
Cash and cash equivalents, beginning of the period	3,008.5		2,375.0
Cash and cash equivalents, end of the period	$	31,~~382~~285.70	$	2,~~598~~758.38

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, 2026
	For the Three Months Ended June 30, 2026
	Preferred stock			Common stock			Additionalpaid-incapital		Accumulatedothercomprehensiveincome (loss)		Retainedearnings		Treasury stock			Totalequity
	Shares	Amount		Shares	Amount								Shares	Amount
Balance, December 31, 2025	—	$	—	170.5	$	0.1	$	863.1	$	(182.0)	$	20,552.7	(23.8)	$	(2,977.1)	$	18,256.8
Net income	—	—		—	—		—		—		319.5		—	—		319.5
Other comprehensive income (loss), net of tax	—	—		—	—		—		41.8		—		—	—		41.8
Issuance of common stock under stock option and stock purchase plans	—	—		0.1	—		15.2		—		—		—	—		15.2
Issuance of common stock under stock award plan	—	—		0.8	—		(70.3)		—		—		—	—		(70.3)
Compensation related to share-based payments	—	—		—	—		88.1		—		—		—	—		88.1
Other	—	—		—	—		0.6		—		—		—	—		0.6
Balance, March 31, 2026	—	$	—	171.4	$	0.1	$	896.7	$	(140.2)	$	20,872.2	(23.8)	$	(2,977.1)	$	18,651.7
Net income	—	—		—	—		—		—		97.5		—	—		97.5
Other comprehensive income (loss), net of tax	—	—		—	—		—		12.5		—		—	—		12.5
Issuance of common stock under stock option and stock purchase plans	—	—		0.1	—		7.5		—		—		—	—		7.5
Issuance of common stock under stock award plan	—	—		—	—		(1.5)		—		—		—	—		(1.5)
Compensation related to share-based payments	—	—		—	—		80.3		—		—		—	—		80.3
Other	—	—		—	—		—		—		—		—	—		—
Balance, June 30, 2026	—	$	—	171.5	$	0.1	$	983.0	$	(127.7)	$	20,969.7	(23.8)	$	(2,977.1)	$	18,848.0
	For the Six Months Ended June 30, 2026
	Preferred stock			Common stock			Additionalpaid-incapital		Accumulatedothercomprehensiveincome (loss)		Retainedearnings		Treasury stock			Totalequity
	Shares	Amount		Shares	Amount								Shares	Amount
Balance, December 31, 2025	—	$	—	170.5	$	0.1	$	863.1	$	(182.0)	$	20,552.7	(23.8)	$	(2,977.1)	$	18,256.8
Net income	—	—		—	—		—		—		417.0		—	—		417.0
Other comprehensive income (loss), net of tax	—	—		—	—		—		54.3		—		—	—		54.3
Issuance of common stock under stock option and stock purchase plans	—	—		0.2	—		22.7		—		—		—	—		22.7
Issuance of common stock under stock award plan	—	—		0.8	—		(71.8)		—		—		—	—		(71.8)
Compensation related to share-based payments	—	—		—	—		168.5		—		—		—	—		168.5
Other	—	—		—	—		0.5		—		—		—	—		0.5
Balance, June 30, 2026	—	$	—	171.5	$	0.1	$	983.0	$	(127.7)	$	20,969.7	(23.8)	$	(2,977.1)	$	18,848.0

	For the Three Months Ended March 31, 2025
	Preferred stock			Common stock			Additionalpaid-incapital		Accumulatedothercomprehensiveincome (loss)		Retainedearnings		Treasury stock			Totalequity
	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

See accompanying notes to these unaudited condensed consolidated financial statements.

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BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - (Continued)

(unaudited, in millions)


	For the Three Months Ended June 30, 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, March 31, 2025	—	$	—	170.3	$	0.1	$	629.9	$	(174.5)	$	19,500.3	(23.8)	$	(2,977.1)	$	16,978.7
Net income	—	—		—	—		—		—		634.8		—	—		634.8
Other comprehensive income (loss), net of tax	—	—		—	—		—		(63.6)		—		—	—		(63.6)




Issuance of common stock under stock option and stock purchase plans	—	—		0.1	—		6.9		—		—		—	—		6.9
Issuance of common stock under stock award plan	—	—		—	—		(0.8)		—		—		—	—		(0.8)
Compensation related to share-based payments	—	—		—	—		78.1		—		—		—	—		78.1
Other	—	—		—	—		(0.1)		—		—		—	—		(0.1)
Balance, June 30, 2025	—	$	—	170.4	$	0.1	$	714.0	$	(238.1)	$	20,135.1	(23.8)	$	(2,977.1)	$	17,634.0

	For the Six Months Ended June 30, 2025
	Preferred stock			Common stock			Additional paid-in capital		Accumulated other comprehensive income (loss)		Retained earnings		Treasury stock			Total Biogen Inc. shareholders’ 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	—	—		—	—		—		—		875.3		—	—		875.3
Other comprehensive income (loss), net of tax	—	—		—	—		—		(101.9)		—		—	—		(101.9)




Issuance of common stock under stock option and stock purchase plans	—	—		0.3	—		22.1		—		—		—	—		22.1
Issuance of common stock under stock award plan	—	—		0.6	—		(40.3)		—		—		—	—		(40.3)
Compensation related to share-based payments	—	—		—	—		162.2		—		—		—	—		162.2
Other	—	—		—	—		0.6		—		—		—	—		0.6
Balance, June 30, 2025	—	$	—	170.4	$	0.1	$	714.0	$	(238.1)	$	20,135.1	(23.8)	$	(2,977.1)	$	17,634.0

See accompanying notes to these unaudited condensed consolidated financial statements.

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BIOGEN INC. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(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~~are afocused ~~broad~~on ~~portfolio~~advancing ofour ~~medicines to treat MS~~pipeline, ~~have~~including ~~introduced~~significant ~~the~~late ~~first~~stage ~~approved treatment for SMA~~programs, ~~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. Weacross ~~support~~multiple ~~our~~modalities. Our drug discovery and development efforts ~~through~~are supported by internal research and development programs, external collaborations and acquisitions of businesses and assets.

Our marketed products include VUMERITY, TYSABRI, TECFIDERA, AVONEX and PLEGRIDY for the treatment of MS; SPINRAZA for the treatment of SMA; SKYCLARYS for the treatment of FA; ~~and~~ QALSODY for the treatment of ALS; SYFOVRE for the treatment of GA; and EMPAVELI for the treatment of PNH, C3G and primary IC-MPGN.

We also have collaborations with Eisai on the commercialization of LEQEMBI for the treatment of Alzheimer's disease and Supernus on the commercialization of ZURZUVAE for the treatment of PPD. We have certain business and financial rights with ~~respect~~current ~~to RITUXAN for the treatment of non-Hodgkin's lymphoma, CLL~~ and other ~~conditions;~~potential ~~RITUXAN HYCELA for the treatment of non~~anti-~~Hodgkin's~~CD20 ~~lymphoma~~therapies, ~~and~~pursuant ~~CLL;~~to ~~GAZYVA~~our ~~for~~collaboration ~~the~~arrangements ~~treatment~~with ~~of CLL~~Genentech, ~~follicular~~a ~~lymphoma~~wholly ~~and~~owned ~~lupus~~member ~~nephritis;~~of ~~OCREVUS for~~ the ~~treatment~~Roche ofGroup. ~~PPMS~~Under ~~and RMS; LUNSUMIO for~~ the ~~treatment~~collaboration ~~of relapsed or refractory follicular lymphoma; COLUMVI~~arrangements, awe ~~bispecific~~currently ~~antibody~~recognize ~~for~~revenue ~~the~~from ~~treatment of non-Hodgkin's lymphoma; and have~~ the ~~option~~following toproducts: ~~add~~OCREVUS, ~~other~~GAZYVA, ~~potential anti-CD20 therapies~~RITUXAN, ~~pursuant~~RITUXAN ~~to our collaboration arrangements with Genentech~~HYCELA, aLUNSUMIO ~~wholly~~and ~~owned member of the Roche Group~~COLUMVI.

We commercialize a portfolio of biosimilars of advanced biologics including: BENEPALI, an etanercept biosimilar referencing ENBREL; IMRALDI, an adalimumab biosimilar referencing HUMIRA; and FLIXABI, an infliximab biosimilar referencing REMICADE.

For additional information on our collaboration arrangements, please read Note 18, 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 2025 Form 10-K. Our accounting policies are described in the Notes to Consolidated Financial Statements in our 2025 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 and six months ended ~~March~~June 3130, 2026, 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.

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.

1314

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BIOGEN INC. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

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 2025 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. 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, and expect to apply this standard prospectively upon adoption.

ASU No. 2025-06, Intangibles - Goodwill and Other - Internal-Use Software (Subtopic 350-40): Targeted Improvements to the Accounting for Internal-Use Software

This standard modernizes the accounting for software costs, including updating guidance on the recognition and measurement of costs incurred in connection with development and implementation activities related to internal-use software.

Annual reporting for fiscal periods beginning after December 15, 2027, and interim periods within those annual reporting periods. 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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BIOGEN INC. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)


Note 2:			Acquisitions

~~Proposed Acquisition of~~ Apellis Pharmaceuticals, Inc.

InOn ~~March~~May 14, 2026, we ~~entered~~completed ~~into~~the anacquisition ~~agreement~~of ~~to acquire~~ all of the issued and outstanding shares of Apellis ~~Pharmaceuticals~~, ~~Inc.,~~ a commercial-stage biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutic compounds to treat diseases with high unmet needs. As a result of this ~~proposed~~ acquisition we ~~would~~acquired ~~acquire~~ two FDA-approved products from Apellis: SYFOVRE (pegcetacoplan injection) for the treatment of ~~geographic atrophy, or~~ GA, an immune-mediated retinal disease; and EMPAVELI (pegcetacoplan) for the treatment of ~~paroxysmal nocturnal hemoglobinuria, or~~ PNH, a rare blood disorder, and ~~C3 glomerulopathy, or~~ C3G, and primary IC-MPGN, rare immune-mediated ~~complex~~kidney ~~membranoproliferative~~diseases. ~~glomerulonephritis,~~The oraddition ~~primary~~of ICApellis is expected to enhance our short-~~MPGN~~ and long-term revenue growth profile by adding two commercialized, indifferentiated, ~~rare~~specialized ~~immune-~~immunology products to our growth portfolio.

14Under the terms of this acquisition, Apellis shareholders were entitled to $41.00 in cash for each issued and outstanding Apellis share, which totaled approximately $5.3 billion, and one contractual, non-transferable contingent value right per share representing the right to receive contingent cash payments of up to an aggregate of $4.00 per share in cash, subject to the achievement of specified annual global net sales thresholds for SYFOVRE. In addition, the total purchase price included approximately $70.7 million of future consideration attributable to pre-acquisition services.

We funded this acquisition of Apellis with available cash and marketable securities on hand, supplemented by the issuance of a $2.0 billion term loan under our 2026 Term Loan and a $400.0 million drawdown from our revolving credit facility.

For additional information on our 2026 Term Loan, please read Note 12, Indebtedness, to these condensed consolidated financial statements.

We 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.

Purchase Price Consideration

Total consideration transferred for the acquisition of Apellis is summarized as follows:


(In millions)	As of May 14, 2026
Cash consideration paid/payable to Apellis shareholders	$	5,406.0

Contingent consideration(1)	4.1
Total consideration	$	5,410.1

(1) Contingent consideration represents the fair value of CVRs that are subject to the achievement of specified annual global net sales thresholds for SYFOVRE.

Apellis Compensation Expense: In connection with our acquisition, we converted Apellis's outstanding unvested equity awards into cash awards totaling $416.3 million. These awards will vest over the remaining requisite service periods of the original awards and are payable only if the applicable service conditions are satisfied, unless accelerated under specified termination provisions.

Of the total $416.3 million, approximately $70.7 million was attributable to pre-acquisition services and is therefore reflected as a component of total purchase price paid. The remaining $345.6 million is attributable to the post-acquisition service period, of which approximately $116.0 million was recognized at transaction close for employees who were immediately terminated upon the acquisition close date. The remaining cash awards will be recognized over the employees' remaining service vesting period; if any of these employees are terminated subsequent to the acquisition date and prior to the estimated service vesting period, all compensation expense not previously recognized will be accelerated due to a double-trigger provision, resulting in immediate recognition.

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BIOGEN INC. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

~~mediated~~Preliminary ~~kidney~~Purchase ~~diseases.~~Price The addition of Apellis is expected to enhance our short- and long-term revenue growth profile by adding two commercialized differentiated immunology and rare disease medicines to our growth portfolio.Allocation

~~Under~~The ~~the~~following ~~terms~~table ofsummarizes the ~~proposed~~preliminary ~~acquisition,~~purchase weprice ~~would~~allocation ~~pay Apellis shareholders $41.00 per share in cash, representing an expected total transaction value~~ of ~~approximately $5.6 billion, and one contractual, non-transferable contingent value right per share representing~~ the ~~right~~separately toidentifiable ~~receive~~assets ~~contingent~~acquired ~~cash~~and ~~payments~~liabilities ofassumed upas ~~to an aggregate~~ of ~~$4.00 in cash~~May 14, ~~subject to the achievement of specified annual global net sales thresholds for SYFOVRE.~~ 2026:

We plan to fund the proposed acquisition of Apellis through approximately $3.6 billion of available cash and marketable securities on hand, supplemented by approximately $2.0 billion in bank loans.


(In millions)	Amounts Recognized as of Acquisition Date May 14, 2026
Cash and cash equivalents	$	310.7
Accounts receivable	384.4
Inventory	712.0
Other current assets	46.1
Intangible assets (completed technology)	4,630.0
Operating lease assets	12.5
Accounts payable	(32.9)
Accrued expense and other	(117.4)
Senior secured term loan	(395.2)
Convertible note	(101.5)
Operating lease liabilities	(18.1)
Deferred tax liability	(522.1)
Other, net	0.1
Total identifiable net assets	4,908.6
Goodwill	501.5
Total assets acquired and liabilities assumed	$	5,410.1

WeInventory: ~~expect~~Total ~~this~~inventory ~~transaction~~acquired towas beapproximately ~~accounted~~$712.0 ~~for~~million, aswhich reflects a ~~business~~step-up ~~combination~~in the fair value of finished goods and towork-in-process ~~include~~inventory for SYFOVRE and EMPAVELI. The fair value was determined based on the ~~results~~estimated selling price of ~~operations~~the ininventory, less the remaining manufacturing and selling costs and a normal profit margin on those manufacturing and selling efforts. The fair value step-up adjustment will be amortized to cost of sales within our condensed consolidated ~~financial~~ statements of income when the inventory is sold, which is expected to be within approximately 3 years from the acquisition date.

Intangible assets: Intangible assets are comprised of $2.4 billion related to EMPAVELI commercialization rights in the U.S., $1.9 billion related to SYFOVRE commercialization rights and $380.0 million related to royalty rights associated with Sobi sales of EMPAVELI outside the U.S. under the brand name ASPAVELI. The estimated fair values of the program related intangible assets were determined using the multi-period excess earnings method and discounted cash flow method, forms of the income approach, and a discount rate of 13.25%. These fair value measurements were based on significant inputs that are not observable in the market and thus represent Level 3 fair value measurements.

The more significant assumptions utilized in our asset valuations related to commercialization rights included the estimated net cash flows for each year for each asset, including total revenue, cost of sales, research and development and other operating expense, the potential regulatory and commercial success risks, as well as other factors.

The more significant assumptions utilized in our asset valuation related to royalty rights included our estimated timing and volume of ASPAVELI sales by Sobi outside the U.S.

Senior secured term loan: In connection with our acquisition of Apellis we assumed responsibility for a senior secured term loan facility with Sixth Street Lending Partners of approximately $395.2 million, relating to the outstanding principal balance as of the acquisition date, accrued interest and prepayment fees incurred as a result of settling the term loan prior to its contractual maturity. We funded a post-close repayment of the senior secured term loan facility prior to its contractual maturity. As of June 30, 2026, the senior secured term loan was paid in full.

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BIOGEN INC. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

Convertible notes: In connection with our acquisition of Apellis we assumed the obligation for outstanding convertible notes of approximately $101.5 million, that upon the close of the acquisition would allow holders the option to convert notes into cash consideration. As of June 30, 2026, the outstanding convertible notes were paid in full with the exception of a de minimis amount. Our subsequent repayment represented a post-acquisition debt extinguishment.

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 $501.5 million, which is not deductible for tax purposes. The goodwill recognized from our acquisition of Apellis is primarily the result of the deferred tax consequences from the transaction recorded for financial statement purposes.

Acquisition-related expense: Acquisition-related expense, which was comprised primarily of regulatory, advisory and legal fees, and other transaction costs, totaled approximately $27.0 million and $30.8 million for the three and six months ended June 30, 2026, respectively, and are included within selling, general and administrative expense within our condensed consolidated statements of income.

Assumptions in the Allocations of Purchase Price

The results of operations of Apellis, along with the estimated fair values of the assets acquired and liabilities assumed in the Apellis acquisition, have been included in our condensed consolidated financial statements since the closing of the Apellis acquisition on May 14, 2026.

The Apellis operations had an immaterial impact to our results of operations for the three and six months ended June 30, 2026. Due to the immateriality of Apellis' revenues and expenses, additional pro forma information combining the results of operations of Biogen and Apellis have not been included.

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, including finalizing our assessment of the intangible assets, inventory, R&D programs, goodwill, leases, contingencies, and 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 from the preliminary estimates.

TJ Biopharma (Hangzhou) Co., Ltd.

In April 2026 we entered into an asset purchase agreement with TJ Biopharma (Hangzhou) Co., Ltd. to acquire TJ Bio's exclusive rights to felzartamab in the greater China region. With this agreement, we own exclusive worldwide rights to felzartamab.

Under the terms of this agreement we made an upfront payment of $100.0 million to TJ Bio, which was recorded in acquired in-process research and development, upfront and milestone expense within our condensed consolidated statements of income for the three and six months ended June 30, 2026.

TJ Bio will also be eligible to receive potential commercial and sales milestone payments of up to $20.0 million and $730.0 million, respectively, if all specified milestones set forth in this collaboration are achieved. In addition, we may pay TJ Bio tiered royalties on potential net sales of felzartamab in the greater China region in the mid-single digit to low-double digit percentages.

Additionally, we assumed regulatory and sales milestone obligations under a pre-existing agreement between TJ Bio and MorphoSys (a wholly-owned subsidiary of Novartis) and may pay MorphoSys tiered royalties on potential net sales of felzartamab in the greater China region.

Alcyone Therapeutics, Inc.

In November 2025 we completed the acquisition of all of the issued and outstanding shares of Alcyone Therapeutics, Inc., a clinical-stage biotechnology company focused on pediatric care through precision CNS therapeutics and dosing platforms. The lead asset acquired is ThecaFlex DRx, an implantable subcutaneous port and catheter device being investigated for the intrathecal delivery of ASOs, including SPINRAZA~~, that is designed to provide an alternative to repeat lumbar punctures in chronic intrathecal administration of medicines~~.

Total consideration for this transaction was approximately $85.0 million, comprising of a $50.0 million payment made upon closing and a $35.0 million payment that was considered probable as of December 31, 2025, and made upon FDA approval of a supplemental application in January 2026. This consideration was recorded within acquired in-process research and development, upfront and milestone expense within our consolidated statements of income for the year ended December 31, 2025, included in our 2025 Form 10-K.18

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BIOGEN INC. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

Total consideration for this transaction of approximately $85.0 million was recorded in acquired in-process research and development, upfront and milestone expense within our consolidated statements of income for the year ended December 31, 2025, and included a $35.0 million payment that was considered probable as of December 31, 2025, and made upon FDA approval of a supplemental application in January 2026.

We may pay additional development and regulatory milestone payments to the former shareholders of Alcyone of up to a total of $75.0 million if approval is received for ThecaFlex DRx administration of SPINRAZA or other additional pipeline products.

We accounted for this transaction as an asset acquisition as the value being acquired primarily relates to a single asset. Under the terms of this acquisition, we will oversee the end-to-end development, manufacturing and commercialization of ThecaFlex DRx.

Alcyone's remaining therapeutic assets were divested from Alcyone into Neela Therapeutics, Inc., a newly formed independent company, prior to the closing of this acquisition.

RayThera Inc.

In June 2026 we entered into a definitive agreement to acquire all of the issued and outstanding shares of RayThera Inc., a private biotechnology company focused on discovering and developing small molecule therapies in immunology. RayThera's portfolio includes a lead program which entered Phase 1 development during the third quarter of 2026 and other anti-inflammatory assets that could potentially treat immune-mediated conditions across a range of indications.

We have agreed to pay an upfront cash payment of $225.0 million upon closing, plus additional potential amounts payable upon the achievement of future clinical and regulatory milestones totaling $775.0 million.

We plan to account for this proposed acquisition as an asset acquisition as the value being acquired primarily relates to the lead program and will record the upfront payment in acquired in-process research and development, upfront and milestone expense within our condensed consolidated statements of income upon the completion of this proposed acquisition. We anticipate the proposed acquisition to close during the third quarter of 2026, subject to the satisfaction of customary closing conditions. Under the terms of this proposed acquisition, we will lead future development, manufacturing and global commercialization efforts.

The proposed acquisition excludes certain preclinical assets, which will be divested from RayThera into a newly formed independent company prior to the expected closing of this acquisition.


Note 3:			Dispositions

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 received a payment of approximately $51.0 million in July 2025 and recognized a de minimis loss within our condensed consolidated statements of income for the ~~three~~six months ended ~~March~~June 3130, 2025.


Note 4:			Restructuring

~~2023~~Apellis ~~Fit for Growth Restructuring Program~~Integration

InFollowing ~~2023~~the weclosing ~~initiated~~of ~~cost~~the ~~saving~~Apellis ~~measures~~acquisition, aswe ~~part~~implemented ofan ~~our~~integration ~~Fit~~plan ~~for~~designed ~~Growth program~~ to ~~reduce~~realize operating ~~costs,~~synergies ~~while~~through ~~improving~~cost ~~operating~~savings ~~efficiency~~ and ~~effectiveness~~avoidance. ~~The~~For ~~Fit~~the ~~for~~three ~~Growth~~and ~~program~~six ~~generated~~months ~~approximately~~ended ~~$1.0 billion~~June in30, ~~gross operating expense savings by the end of 2025~~2026, ~~some~~we ofrecognized ~~which~~approximately ~~has been reinvested in various initiatives~~$153.2 million ~~The~~of ~~Fit~~net ~~for~~pre-tax ~~Growth~~restructuring ~~program~~charges, ~~included~~primarily ~~net~~consisting ~~headcount reductions~~ of ~~approximately~~employee ~~1,400~~severance ~~employees~~costs and wethe ~~incurred~~acceleration ~~total~~of ~~restructuring~~bonus ~~charges~~payments ofthat ~~approximately~~were ~~$320.0 million~~subject byto ~~the~~a ~~end~~double-trigger ~~of 2025~~provision.

For the three months ended March 31, 2025, we recorded approximately $35.3 million in restructuring charges related to severance costs from our Fit for Growth program within restructuring charges in our condensed consolidated statements of income.19

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Restructuring Reserve

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 generated approximately $1.0 billion in gross operating expense savings by the end of 2025, some of which has been reinvested in various initiatives. The Fit for Growth program included net headcount reductions of approximately 1,400 employees and we incurred total restructuring charges of approximately $320.0 million by the end of 2025.

For the six months ended June 30, 2025, we recorded approximately $34.2 million in restructuring charges related to severance costs from our Fit for Growth program within restructuring charges in our condensed consolidated statements of income.

Restructuring Reserve

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

	Workforce Reductions
(In millions)	2026		2025
Restructuring reserve as of January 1	$	15.8		$	31.9
Expense	7.9			35.3
Payment	(10.3)			(25.8)
Foreign currency and other adjustments	0.2			(1.0)
Restructuring reserve as of March 31	$13.6	~~13.6~~		$40.4	~~40.4~~
Expense	165.4			(0.7)
Payment	(143.2)			(9.5)
Foreign currency and other adjustments	0.1			(1.0)
Restructuring reserve as of June 30	$	35.9		$	29.2

1620

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Note 5:			Revenue

Product Revenue

Revenue by product is summarized as follows:

	For the Three Months Ended March 31,
	For the Three Months Ended June 30,
	2026						2025
(In millions)	UnitedStates		Rest ofWorld		Total		UnitedStates		Rest ofWorld		Total
Multiple Sclerosis:
TECFIDERA	$	3132.4	$	7858.15	$	~~109~~90.59	$	3947.82	$	~~166~~146.34	$	~~206~~193.16
VUMERITY	~~153~~172.40		2524.65		~~179~~196.05		~~117~~188.10		2124.73		~~138~~212.83
Total Fumarate	~~184~~204.84		~~103~~83.70		~~288~~287.54		~~156~~235.92		~~188~~170.07		~~344~~405.9
AVONEX	~~108~~120.59		5449.71		~~163~~170.20		~~108~~121.67		5856.20		~~166~~177.87
PLEGRIDY	2425.32		4029.09		6455.31		2428.13		3540.47		5969.50
Total Interferon	~~132~~146.81		9479.70		~~227~~225.51		~~132~~150.70		9396.67		~~226~~246.37
TYSABRI	~~241~~270.85		~~199~~180.73		~~441~~450.58		~~200~~272.82		~~180~~182.74		~~381~~454.56
FAMPYRA(1)	—		—		—		—		0.3		0.3
Subtotal: Multiple Sclerosis	621.0		342.3		963.3		657.4		449.8		1,107.2
Subtotal: Multiple Sclerosis	559.4		398.1		957.5		490.4		462.6		953.0
Rare Disease:
SPINRAZA	~~142~~204.23		~~231~~197.86		~~374~~401.09		~~154~~149.43		~~269~~243.54		~~423~~392.97
SKYCLARYS	7182.83		7885.96		~~150~~167.79		6978.10		5452.83		~~123~~130.93
QALSODY	108.53		2223.06		3231.59		7.5		812.05		1520.50
Subtotal: Rare Disease	~~224~~294.59		~~332~~306.78		~~557~~601.27		~~231~~234.08		~~332~~308.32		~~563~~543.30
Specialized Immunology:
SYFOVRE(1)	97.4		—		97.4		—		—		—
EMPAVELI(1)	30.4		—		30.4		—		—		—
Subtotal: Specialized Immunology	127.8		—		127.8		—		—		—
Biosimilars:
BENEPALI	—		~~122~~106.18		~~122~~106.18		—		~~111~~112.31		~~111~~112.31
IMRALDI	—		4937.68		4937.68		—		4746.47		4746.47
FLIXABI	—		108.51		108.51		—		1314.13		1314.13
BYOOVIZ(2)	—0.1		—		—0.1		4.2.5		46.71		8.96
TOFIDENCE(2)	—		—		—		0.1		—		0.1
Subtotal: Biosimilars	0.1		152.7		152.8		2.5		179.2		181.7
Subtotal: Biosimilars	—		182.2		182.2		4.3		176.5		180.8
Other:
ZURZUVAE	5570.37		0.1		5570.48		2746.74		—		2746.74
Other(3)	—		—		—		~~0.4~~—		10.34		10.74
Subtotal: Other	5570.37		0.1		5570.48		2846.14		10.34		2946.48
Total product revenue, net	$	~~839~~1,114.25	$	~~913~~801.19	$	1,~~752~~916.34	$	~~753~~941.81	$	~~972~~937.76	$	1,~~726~~878.57

(1) EMPAVELI and SYFOVRE were obtained as part of our acquisition of Apellis in May 2026.

(2) In the fourth quarter of 2025 we completed the sale of our rights to BYOOVIZ.

(3) Other includes FUMADERM.

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	For the Six Months Ended June 30,
	2026						2025
(In millions)	United States		Rest of World		Total		United States		Rest of World		Total
Multiple Sclerosis:
TECFIDERA	$	63.8	$	136.6	$	200.4	$	87.0	$	312.7	$	399.7
VUMERITY	325.4		50.1		375.5		305.1		46.0		351.1
Total Fumarate	389.2		186.7		575.9		392.1		358.7		750.8
AVONEX	229.4		103.8		333.2		230.3		114.2		344.5
PLEGRIDY	49.5		69.9		119.4		52.4		76.1		128.5
Total Interferon	278.9		173.7		452.6		282.7		190.3		473.0
TYSABRI	512.3		380.0		892.3		473.0		363.1		836.1
FAMPYRA(1)	—		—		—		—		0.3		0.3
Subtotal: Multiple Sclerosis	1,180.4		740.4		1,920.8		1,147.8		912.4		2,060.2

Rare Disease:
SPINRAZA	346.5		429.4		775.9		303.7		512.9		816.6
SKYCLARYS	154.1		164.5		318.6		147.1		107.1		254.2
QALSODY	18.8		45.6		64.4		15.0		20.5		35.5
Subtotal: Rare Disease	519.4		639.5		1,158.9		465.8		640.5		1,106.3

Specialized Immunology:
SYFOVRE(2)	97.4		—		97.4		—		—		—
EMPAVELI(2)	30.4		—		30.4		—		—		—
Subtotal: Specialized Immunology	127.8		—		127.8		—		—		—

Biosimilars:
BENEPALI	—		228.9		228.9		—		223.4		223.4
IMRALDI	—		87.4		87.4		—		94.1		94.1
FLIXABI	—		18.6		18.6		—		27.4		27.4
BYOOVIZ(3)	0.1		—		0.1		6.7		10.8		17.5
TOFIDENCE(3)	—		—		—		0.1		—		0.1
Subtotal: Biosimilars	0.1		334.9		335.0		6.8		355.7		362.5

Other:
ZURZUVAE	126.0		0.2		126.2		74.1		—		74.1


Other(4)	—		—		—		0.4		1.7		2.1
Subtotal: Other	126.0		0.2		126.2		74.5		1.7		76.2
Total product revenue, net	$	1,953.7	$	1,715.0	$	3,668.7	$	1,694.9	$	1,910.3	$	3,605.2

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

(2) InEMPAVELI ~~2025~~and weSYFOVRE ~~completed~~were ~~the~~obtained ~~sale~~as part of our ~~rights~~acquisition toof ~~TOFIDENCE~~Apellis ~~and~~in ~~BYOOVIZ~~May 2026.

(3) ~~Other~~In ~~includes~~2025 ~~FUMADERM~~we completed the sale of our rights to TOFIDENCE and ~~ADUHELM~~BYOOVIZ.

We(4) ~~recognized~~Other ~~revenue~~includes ~~from~~FUMADERM ~~two wholesalers accounting for 27.3%~~ and 14ADUHELM.~~7% of gross product revenue for the three months ended March 31, 2026, compared to 25.9% and 14.1% of gross product revenue for the three months ended March 31, 2025.~~

17We recognized revenue from three wholesalers accounting for 29.9%, 16.5% and 10.9%, respectively of gross product revenue for the three months ended June 30, 2026, and 28.7%, 15.7% and 9.8%, respectively of gross product revenue for the six months ended June 30, 2026.

We recognized revenue from two wholesalers accounting for 28.2% and 15.8% of gross product revenue for the three months ended June 30, 2025, and 27.1% and 15.0% of gross product revenue for the six months ended June 30, 2025.

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

(In millions)	Discounts		ContractualAdjustments		Returns		Total
Balance, December 31, 2025	$	115.7	$	1,046.1	$	49.0	$	1,210.8
Current provisions relating to sales in current year	214.0		683.7		7.3		905.0
Apellis acquisition	13.3		32.3		6.4		52.0
Adjustments relating to prior years	0.8		(28.4)		10.4		(17.2)
Current provisions relating to sales in current year	439.8		1,352.1		13.4		1,805.3
Payments/credits relating to sales in current year	(133.4)		(255.3)		(0.1)		(388.8)
Adjustments relating to prior years	(2.0)		(69.2)		13.7		(57.5)
Payments/credits relating to sales in prior years	(92.3)		(426.0)		(14.9)		(533.2)
Payments/credits relating to sales in current year	(316.1)		(745.0)		(0.1)		(1,061.2)
Balance, March 31, 2026	$	104.8	$	1,020.1	$	51.7	$	1,176.6
Payments/credits relating to sales in prior years	(129.0)		(549.5)		(27.9)		(706.4)
Balance, June 30, 2026	$	121.7	$	1,066.8	$	54.5	$	1,243.0

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

(In millions)	As of ~~March~~June 3130, 2026		As of December 31, 2025
Component of accrued expense and other	$	~~961~~980.12	$	1,000.4
Reduction of accounts receivable	~~215~~262.58		210.4
Total revenue-related reserves	$	1,~~176~~243.60	$	1,210.8

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,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Royalty revenue on sales of OCREVUS	$	~~317~~381.24	$	~~288~~353.8	$	698.6	$	642.6
Biogen’s share of pre-tax profits in the U.S. for RITUXAN, GAZYVA and LUNSUMIO	94125.7		83107.7		220.4		191.4
Other revenue from anti-CD20 therapeutic programs	76.24		5.78		13.6		11.5
Total revenue from anti-CD20 therapeutic programs	$	~~419~~513.15	$	~~378~~467.23	$	932.6	$	845.5

For additional information on our collaboration arrangements with Genentech, please read Note 18, 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 and six months ended ~~March~~June 3130, 2026 ~~and 2025~~, we recognized Alzheimer's collaboration revenue of approximately $5963.57 million and $33123.02 million, respectively, compared to $54.9 million and $87.9 million, respectively, in the prior year comparative periods.

For additional information on our collaboration arrangements with Eisai, please read Note 18, Collaborative and Other Relationships, to these condensed consolidated financial statements.

~~Contract Manufacturing, Royalty and Other Revenue~~23

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

	For the Three Months Ended March 31,
(In millions)	2026		2025
Contract manufacturing revenue	$	237.2	$	282.3
Royalty and other revenue	9.7		11.0
Total contract manufacturing, royalty and other revenue	$	246.9	$	293.3

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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 June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Contract manufacturing revenue	$	232.4	$	225.0	$	469.6	$	507.3
Royalty and other revenue	10.0		19.6		19.7		30.6
Total contract manufacturing, royalty and other revenue	$	242.4	$	244.6	$	489.3	$	537.9

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, including arrangements with Sobi that we inherited through our acquisition of Apellis.

For additional information on our ~~license~~ arrangements with Samsung Bioepis, Eisai and ~~our collaboration arrangements with Eisai~~Sobi, please read Note 18, 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~~June 3130, 2026		As of December 31, 2025
Raw materials	$	~~278~~308.70	$	293.4
Work in process	1,~~351~~655.60		1,595.2
Finished goods	~~458~~557.20		424.9
Total inventory	$	2,~~088~~520.50	$	2,313.5
Balance Sheet Classification:
Inventory	$	12,~~949~~384.03	$	2,168.1
Investments and other assets	~~139~~135.57		145.4
Total inventory	$	2,~~088~~520.50	$	2,313.5

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

As a result of our acquisition of ~~Reata~~Apellis in ~~September~~May ~~2023~~2026, we recorded aapproximately ~~fair~~$712.0 million ~~value~~of ~~step-up~~acquired ~~adjustment~~inventory related to ~~the~~SYFOVRE ~~acquired~~and ~~inventory~~EMPAVELI, ofinclusive ~~SKYCLARYS~~ of ~~approximately $1.3 billion. This~~ fair value step-up ~~adjustment~~adjustments isrelated ~~being amortized~~ to ~~cost of sales as~~ the acquired inventory isof ~~sold~~SYFOVRE ~~or research~~ and ~~development~~EMPAVELI ~~expense~~totaling asapproximately ~~the inventory is used for clinical purposes within our condensed consolidated statements of income~~$567.5 million. We expect ~~this~~these ~~amount~~amounts to be fully amortized by the end of ~~2028~~2029. For the three ~~months ended March 31, 2026~~ and ~~2025,~~six ~~amortization from the fair value step-up adjustment was approximately $107.6 million and $51.4 million, respectively. For the three~~ months ended ~~March~~June 3130, 2026, amortization from the fair value step-up ~~adjustment includes approximately $56.8 million of inventory used for clinical purposes~~adjustments, which iswas ~~reflected~~recorded inas ~~research~~a ~~and~~component ~~development~~of ~~expense~~cost of sales within our condensed consolidated statements of income, was approximately $69.7 million. For additional information on our acquisition of ~~Reata~~Apellis, please read Note 2, Acquisitions, to ~~our~~these condensed consolidated financial statements ~~included in our 2025 Form 10-K~~.

1924

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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. We expect this amount to be fully amortized by the end of 2028. For the three and six months ended June 30, 2026, amortization from the fair value step-up adjustment was approximately $133.1 million and $240.7 million, respectively, compared to $52.5 million and $103.9 million, respectively, in the prior year comparative periods. For the three and six months ended June 30, 2026, amortization from the fair value step-up adjustment includes approximately $37.5 million and $94.3 million, respectively, of inventory used for clinical purposes, which is reflected in research and development expense within our condensed consolidated statements of income. For additional information on our acquisition of Reata, please read Note 2, Acquisitions, to our consolidated financial statements included in our 2025 Form 10-K.

These fair value step-up adjustments are being amortized to cost of sales as the inventory is sold or to research and development expense as the inventory is used for clinical purposes within our condensed consolidated statements of income.


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, 2026						As of December 31, 2025
		As of June 30, 2026						As of December 31, 2025
(In millions)	Estimated Life	Cost		AccumulatedAmortization		Net		Cost		AccumulatedAmortization		Net
Completed technology	1-30 years	$	1418,~~078~~708.8	$	(6,~~824~~992.34)	$	711,~~254~~716.54	$	14,067.3	$	(6,687.8)	$	7,379.5
In-process research and development	Indefinite until commercialization	1,~~635~~636.0		—		1,~~635~~636.0		1,635.0		—		1,635.0
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		$	1520,~~877~~508.8	$	(6,~~824~~992.34)	$	913,~~053~~516.54	$	15,866.3	$	(6,687.8)	$	9,178.5

Amortization and Impairments

For the three and six months ended ~~March~~June 3130, 2026, amortization and impairment of acquired intangible assets totaled $~~136~~168.52 million and $304.7 million, compared to $~~111~~130.89 million inand ~~the prior year comparative period~~$242.7 ~~The~~million, ~~increase~~respectively, ~~was~~in ~~primarily due to amortization for~~ the ~~acquired~~prior ~~intangible~~year ~~assets~~comparative ~~associated with SKYCLARYS and TYSABRI~~periods.

For the three and six months ended ~~March~~June 3130, 2026, amortization of acquired intangible assets, excluding impairment charges, totaled $168.2 million and ~~2025~~$304.7 million, respectively, compared to $127.4 million and $239.2 million, respectively in the prior year comparative periods. The increases were primarily due to higher rates of amortization for the acquired intangible assets associated with SKYCLARYS. Additionally, we ~~had~~recorded no$22.6 ~~impairment~~million ~~charges~~of amortization for the acquired intangible assets as part of our acquisition of Apellis for the three and six months ended June 30, 2026.

For the three and six months ended June 30, 2026, we had no impairment charges. For the three and six months ended June 30, 2025, amortization and impairment of acquired intangible assets reflect the impact of a $3.5 million impairment charge related to a compound acquired from HI-Bio.

Completed Technology

Completed technology primarily relates to our other marketed products and programs acquired through asset acquisitions, licenses and business combinations. ~~Completed~~In ~~technology~~connection ~~intangible~~with ~~assets~~our ~~are~~acquisition ~~amortized~~of ~~over~~Apellis ~~their~~we acquired completed technology with an estimated ~~useful~~fair ~~lives~~value of approximately $4.6 billion, ~~which~~comprised ~~range~~of ~~between~~$2.4 billion ~~approximately~~related to EMPAVELI commercialization rights in the U.S., $1.9 billion related to 30SYFOVRE ~~years,~~commercialization ~~with~~rights aand ~~remaining~~$380.0 million ~~weighted~~related ~~average~~to ~~useful~~royalty ~~life~~rights ofassociated 11with ~~years~~Sobi assales of ~~March~~EMPAVELI ~~31,~~outside ~~2026~~the U.S. under the brand name ASPAVELI.

~~IPR&D~~Completed ~~Related~~technology intangible assets are amortized over their estimated useful lives, which range between approximately 1 to ~~Business~~30 ~~Combinations~~years, with a remaining weighted average useful life of 13 years as of June 30, 2026.

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.25

The carrying value associated with our IPR&D assets as of March 31, 2026 and December 31, 2025, 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.

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, 2026
2026 (remaining nine months)	$	400.0
2027	485.0
2028	525.0
2029	575.0
2030	650.0
2031	700.0

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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 June 30, 2026
2026 (remaining six months)	$	345.0
2027	665.0
2028	735.0
2029	815.0
2030	925.0
2031	1,025.0

Goodwill

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

(In millions)	As of ~~March~~June 3130, 2026
Goodwill, December 31, 2025	$	6,491.1
Other(1)	(2.4)
Goodwill resulting from Apellis acquisition	501.5
Goodwill, March 31, 2026	$	6,488.7
Other(1)	(1.8)
Goodwill, June 30, 2026	$	6,990.8

(1) Other includes adjustments related to foreign currency exchange rate fluctuations.

AsFor ofadditional ~~March~~information ~~31,~~on ~~2026,~~our weacquisition ~~had~~of noApellis, ~~impairment~~please ~~losses~~read ~~related~~Note 2, Acquisitions, to ~~goodwill~~these condensed consolidated financial statements.

As of June 30, 2026, we had no impairment losses related to goodwill.


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, 2026
	As of June 30, 2026
(In millions)	Total		Quoted Pricesin ActiveMarkets(Level 1)		SignificantOther ObservableInputs(Level 2)		SignificantUnobservableInputs(Level 3)
Assets:
Cash equivalents	$	~~2,512~~569.84	$	—	$	~~2,512~~569.84	$	—
Marketable debt securities:
Marketable equity securities	184.0		184.0		—		—
Corporate debt securities	734.2		—		734.2		—
Government securities	547.3				547.3		—
Mortgage and other asset backed securities	84.1				84.1		—
Marketable equity securities	137.4		137.4		—		—
Other current assets:
Derivative contracts	1921.16		—		1921.16		—
Other non-current assets:
Convertible note(1)	35.0		—		—		35.0
Convertible notes(1)	35.0		—		—		35.0
Plan assets for deferred compensation	5664.82		—		5664.82		—
Derivative contracts	57.97		—		57.97		—
Total	$	~~4,132~~881.69	$	~~137~~184.40	$	~~3,960~~662.29	$	35.0
Liabilities:
Other current liabilities:
Derivative contracts	$	3826.26	$	—	$	3826.26	$	—
Other non-current liabilities:
Contingent consideration obligations	~~266~~273.95		—		—		~~266~~273.95
Total	$	~~305~~300.1	$	—	$	3826.26	$	~~266~~273.95

(1) Convertible notes includes a $30.0 million convertible note we invested in as part of our strategic research arrangement with City Therapeutics during 2025, as well as a $5.0 million convertible note we invested into Neela Therapeutics, Inc. during 2025. We elected the fair value option for both convertible notes. For additional information on the arrangement with City Therapeutics, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in our 2025 Form 10-K.26

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(1) Convertible notes includes a $30.0 million convertible note we invested in City Therapeutics as part of our strategic research arrangement with the company during 2025, as well as a $5.0 million convertible note we invested into Neela Therapeutics, Inc. during 2025. We elected the fair value option for both convertible notes. For additional information on the arrangement with City Therapeutics, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in our 2025 Form 10-K.


	Fair Value Measurements on a Recurring Basis
	As of December 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	$	2,233.2	$	—	$	2,233.2	$	—
Marketable debt securities:
Corporate debt securities	537.6		—		537.6		—
Government securities	648.8		—		648.8		—
Mortgage and other asset backed securities	52.7		—		52.7		—
Marketable equity securities	118.1		118.1		—		—
Other current assets:
Derivative contracts	10.0		—		10.0		—
Other non-current assets:
Convertible notes(1)	35.0		—		—		35.0
Plan assets for deferred compensation	52.2		—		52.2		—
Derivative contracts	0.4		—		0.4		—
Total	$	3,688.0	$	118.1	$	3,534.9	$	35.0
Liabilities:
Other current liabilities:
Derivative contracts	$	56.7	$	—	$	56.7	$	—

Other non-current liabilities:
Derivative contracts	2.2		—		2.2		—
Contingent consideration obligations	246.4		—		—		246.4
Total	$	305.3	$	—	$	58.9	$	246.4

(1) Convertible notes includes a $30.0 million convertible note we invested in City Therapeutics as part of our strategic research arrangement with ~~City~~the ~~Therapeutics~~company during 2025, as well as a $5.0 million convertible note we invested into Neela Therapeutics, Inc. during 2025. We elected the fair value option for both convertible notes. For additional information on the arrangement with City Therapeutics, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in our 2025 Form 10-K.

Our marketable equity securities represent investments in publicly traded equity securities. Our ability to liquidate our investment in Denali 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 investment in Denali common stock, please read Note 9, Financial Instruments, and Note 17, Other Consolidated Financial Statement Detail, to these condensed consolidated financial statements.

There have been no material impairments of our assets measured and carried at fair value asnor ~~of March 31, 2026 and December 31, 2025. In addition, there have been no~~ changes to our valuation techniques as of ~~March~~June 3130, 2026 and December 31, 2025.

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 2025 Form 10-K.

Level 3 Assets and Liabilities Held at Fair Value

The following tables present 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:

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Quantitative Information about Level 3 Fair Value Measurements

As of March 31, 2026

As of June 30, 2026

(In millions)

Fair Value

Valuation Technique

SignificantUnobservable Input(s)

Range

Weighted Average

Liabilities:

Contingent consideration obligations

~~266~~269.94

Discounted cash flow

Discount rate

5.79%

Expected timing of achievement of development milestones

2028

—

Quantitative Information about Level 3 Fair Value Measurements

As of December 31, 2025

(In millions)

Fair Value

Valuation Technique

Significant
Unobservable Input(s)

Range

Weighted Average

Liabilities:

Contingent consideration obligations

246.4

Discounted cash flow

Discount rate

5.3% - 5.4%

5.4%

Expected timing of achievement of development milestones

2028 - 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 75.0% to approximately 95.0% as of ~~March~~June 3130, 2026.

There were no transfers of assets or liabilities into or out of Level 3 as of ~~March~~June 3130, 2026 and December 31, 2025.

Contingent Consideration Obligations

In connection with our acquisition of HI-Bio in July 2024 and our acquisition of Apellis in May 2026 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:

	For the Three Months Ended March 31,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Fair value, beginning of period	$	~~246~~266.49	$	~~512~~522.84	$	246.4	$	512.8
Changes in fair value	20.5		9.6
Contingent consideration related to the acquisition of Apellis	4.1		—		4.1		—
Fair value, end of period	$	266.9	$	522.4
Changes in fair value	2.5		13.2		23.0		22.8
Payments	—		(0.7)		—		(0.7)
Fair value, end of period	$	273.5	$	534.9	$	273.5	$	534.9

Changes in the fair value of our contingent consideration obligations, other than changes due to payments, are recognized as a (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 2025 Form 10-K.

As of ~~March~~June 3130, 2026 and December 31, 2025, ~~approximately~~contingent consideration liabilities of $~~266~~273.95 million and $246.4 million, respectively, ~~of the fair value of our contingent consideration obligations~~ were classified as long-term and reflected as a component of other long-term liabilities in our condensed consolidated balance sheets.

For the three and six months ended ~~March~~June 3130, 2026, changes in the fair value of our contingent consideration obligations were primarily due to changes in the probabilities of success and expected timing of the achievement of certain remaining developmental milestones related to our acquisition of HI-Bio, and the recognition of a $4.1 million obligation related to the acquisition of Apellis.

During the second quarter of 2025 the first milestone related to the fourth patient dosed in a phase 3 clinical trial of felzartamab for AMR was achieved, resulting in a $150.0 million milestone payment made to the former shareholders of HI-Bio, which was paid during the third quarter of 2025. In October 2025 the second milestone related to the fourth patient dosed in a phase 3 clinical trial of felzartamab for IgAN was achieved, resulting in a $150.0 million milestone payment made to the former shareholders of HI-Bio during the fourth quarter of 2025.

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(unaudited, continued)

related to the fourth patient dosed in a phase 3 clinical trial of felzartamab for IgAN was achieved, resulting in a $150.0 million milestone payment made to the former shareholders of HI-Bio during the fourth quarter of 2025.

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, 2026				As of December 31, 2025
	As of June 30, 2026				As of December 31, 2025
(In millions)	FairValue		CarryingValue		FairValue		CarryingValue
Current portion:
2026 Term Loan 364-day tranche(1)	$	799.9	$	800.0	$	—	$	—
Current portion of notes payable	799.9		800.0		—		—
Non-current portion:
2.250% Senior Notes due May 1, 2030	$	1,369.5	$	1,495.9	$	1,378.7	$	1,495.7
2026 Term Loan two-year tranche(1)	999.9		1,000.0		—		—
5.050% Senior Notes due January 15, 2031	407.5		398.1		413.0		398.0
2.250% Senior Notes due May 1, 2030	1,368.7		1,496.2		1,378.7		1,495.7
5.750% Senior Notes due May 15, 2035	672.5		645.6		684.5		645.5
5.050% Senior Notes due January 15, 2031	404.6		398.1		413.0		398.0
5.200% Senior Notes due September 15, 2045	1,004.8		1,101.6		1,029.5		1,101.5
5.750% Senior Notes due May 15, 2035	675.1		645.7		684.5		645.5
3.150% Senior Notes due May 1, 2050	943.9		1,475.8		973.0		1,475.6
5.200% Senior Notes due September 15, 2045	1,031.3		1,101.7		1,029.5		1,101.5
3.250% Senior Notes due February 15, 2051	443.6		481.3		461.8		480.3
3.150% Senior Notes due May 1, 2050	973.4		1,476.0		973.0		1,475.6
6.450% Senior Notes due May 15, 2055	725.9		690.2		737.6		690.2
3.250% Senior Notes due February 15, 2051	458.9		482.3		461.8		480.3
Non-current portion of notes payable	5,567.7		6,288.5		5,678.1		6,286.8
6.450% Senior Notes due May 15, 2055	744.0		690.2		737.6		690.2
Total notes payable	$	5,567.7	$	6,288.5	$	5,678.1	$	6,286.8
Non-current portion of notes payable	6,655.9		7,290.2		5,678.1		6,286.8
Total notes payable	$	7,455.8	$	8,090.2	$	5,678.1	$	6,286.8

~~The~~(1) ~~fair~~In ~~values~~connection ofwith ~~each of~~ our ~~series~~acquisition of ~~Senior~~Apellis ~~Notes~~we ~~were~~drew ~~determined through market, observable and corroborated sources~~$2.0 billion ~~The~~from ~~changes in~~ the ~~fair values of our Senior Notes as of March 31,~~ 2026, ~~compared~~Term ~~to December 31~~Loan, ~~2025,~~comprised ~~are~~of ~~primarily~~a ~~related~~$1.0 billion tofloating ~~increases~~rate in364-day ~~U.S.~~tranche ~~treasury yields~~ and ~~credit~~a ~~spreads~~$1.0 billion ~~used~~floating torate ~~value~~two-year ~~our Senior Notes since December 31, 2025~~tranche. For additional information ~~related~~on to our ~~Senior~~2026 ~~Notes~~Term Loan, please read Note 1312, Indebtedness, to ~~our~~these condensed consolidated financial statements ~~included in our 2025 Form 10-K~~.

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 June 30, 2026, compared to December 31, 2025, are primarily related to increases in U.S. treasury yields, partially offset by lower credit spreads used to value our Senior Notes since December 31, 2025. For additional information related to our Senior Notes, please read Note 13, Indebtedness, to our consolidated financial statements included in our 2025 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~~June 3130, 2026		As of December 31, 2025
Money market funds	$	~~1,949~~569.4	$	2,027.7
Overnight reverse repurchase agreements	~~34.3~~—		70.0
Short-term debt securities	~~391.8~~—		15.4
Commercial paper	~~137.3~~—		120.1
Total	$	~~2,512~~569.84	$	2,233.2

The carrying values of our money market funds, overnight reverse repurchase agreements, short-term debt securities and commercial paper, including accrued interest, approximate 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 debt and equity securities, classified as available-for-sale:

	As of March 31, 2026
	As of June 30, 2026
(In millions)	AmortizedCost		GrossUnrealizedGains		GrossUnrealizedLosses		FairValue
Marketable debt securities
Corporate debt securities:
Current	$	418.2	$	—	$	(0.7)	$	417.5
Non-current	317.8		—		(1.1)		316.7
Government securities:
Current	482.6		—		(0.1)		482.5
Non-current	64.8		—		—		64.8
Mortgage and other asset backed securities:
Non-current	84.2		—		(0.1)		84.1
Total marketable debt securities	$	1,367.6	$	—	$	(2.0)	$	1,365.6
Marketable equity securities
Marketable equity securities, non-current	$	227.87	$	—	$	(9043.47)	$	~~137~~184.40
Total marketable equity securities	$	227.87	$	—	$	(9043.47)	$	~~137~~184.40


	As of December 31, 2025
(In millions)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value
Marketable debt securities
Corporate debt securities:
Current	$	246.8	$	—	$	—	$	246.8
Non-current	290.6		0.2		—		290.8
Government securities:
Current	560.4		—		—		560.4
Non-current	88.4		—		—		88.4
Mortgage and other asset backed securities:

Non-current	52.7		—		—		52.7
Total marketable debt securities	$	1,238.9	$	0.2	$	—	$	1,239.1

Marketable equity securities

Marketable equity securities, non-current	$	227.7	$	—	$	(109.6)	$	118.1
Total marketable equity securities	$	227.7	$	—	$	(109.6)	$	118.1

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

Summary of Contractual Maturities: Available-for-Sale Debt Securities

The estimated fair value and amortized cost of our marketable debt securities classified as available-for-sale by contractual maturity are summarized as follows:

	As of March 31, 2026				As of December 31, 2025
			As of December 31, 2025
(In millions)	~~EstimatedFair Value~~		~~AmortizedCost~~		EstimatedFair Value		AmortizedCost
Due in one year or less	$	~~900.0~~	$	~~900.8~~	$	807.2	$	807.2
Due after one year through five years	~~454.7~~		~~455.9~~		419.5		419.3
Due after five years	~~10.9~~		~~10.9~~		12.4		12.4
Total marketable debt securities	$	~~1,365.6~~	$	~~1,367.6~~	$	1,239.1	$	1,238.9

~~The~~We ~~average~~funded ~~maturity~~our Apellis acquisition through available cash, cash equivalents and marketable securities. As of June 30, 2026, we have sold all of our marketable debt securities. ~~classified~~For asadditional ~~available-for-sale~~information ason our acquisition of ~~March~~Apellis, 31please read Note 2, ~~2026~~Acquisitions, ~~was~~to ~~approximately~~these 10condensed ~~months~~consolidated financial statements.

Proceeds from Marketable Debt Securities

The proceeds from maturities and sales of marketable debt securities and any resulting realized gains and losses are summarized as follows:

	For the Three Months Ended March 31,
(In millions)	2026		2025
Proceeds from maturities and sales	$	625.2	$	—

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(unaudited, continued)


	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Proceeds from maturities and sales	$	1,515.2	$	—	$	2,140.4	$	—
Realized gains	0.2		—		0.2		—
Realized losses	1.5		—		1.5		—

Realized losses for the three and six months ended June 30, 2026, primarily relate to sales of corporate bonds.

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~~June 3130, 2026 and December 31, 2025, our strategic investment portfolio was comprised of investments totaling $~~205~~248.37 million and $186.6 million, respectively, which are included in investments and other assets within our condensed consolidated balance sheets.

The increase in our strategic investment portfolio as of ~~March~~June 3130, 2026, compared to December 31, 2025, was primarily due to the increase in the fair value of our investment in Denali common stock.

For additional information on our investments in Denali common stock, please read Note 8, Fair Value Measurements, and Note 17, Other Consolidated Financial Statement Detail, to these condensed consolidated financial statements.


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~~June 3130, 2026 and December 31, 2025, had durations of 1 to 18 months and 1 to 21 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.

26The 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 June 30, 2026		As of December 31, 2025
Euro	$	1,275.3	$	1,531.0
Swiss franc	108.8		—
British pound	49.5		—

Polish zloty	19.8		—
Canadian dollar	17.4		—
Total foreign currency forward contracts and options	$	1,470.8	$	1,531.0

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(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, 2026		As of December 31, 2025
Euro	$	1,332.6	$	1,531.0
Swiss franc	165.6		—
British pound	76.2		—
Polish zloty	33.0		—
Canadian dollar	24.7		—
Total foreign currency forward contracts and options	$	1,632.1	$	1,531.0

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~~June 3130, 2026		As of December 31, 2025
Unrealized gains	$	913.76	$	—
Unrealized (losses)	(2410.45)		(73.3)
Net unrealized gains (losses)	$	~~(14~~3.7)1	$	(73.3)

We expect net unrealized ~~losses~~gains of approximately $143.71 million to be settled over the next 18 months, of which approximately $161.47 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~~June 3130, 2026 and December 31, 2025, credit risk did not materially change the fair value of our foreign currency forward contracts and forward currency options.

The following ~~table~~tables ~~summarizes~~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,
For the Three Months Ended June 30,
Net Gains/(Losses)Reclassified from AOCI into Operating Income (in millions)					Net Gains/(Losses) Excluded from Effectiveness Testing andRecognized in Operating Income (in millions)
Location	2026		2025		Location	2026		2025
Revenue	$	(249.32)	$	10(22.9)	Revenue	$	4(3.10)	$	(0.48)
Operating expense	(0.72)		06.76		Operating expense	(10.16)		(1.0.8)
For the Six Months Ended June 30,
Net Gains/(Losses)Reclassified from AOCI into Operating Income (in millions)					Net Gains/(Losses) Excluded from Effectiveness Testing andRecognized in Operating Income (in millions)
Location	2026		2025		Location	2026		2025
Revenue	$	(33.5)	$	(12.0)	Revenue	$	1.1	$	(0.4)
Operating expense	0.5		7.3		Operating expense	(1.7)		(1.8)

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 $1,~~241~~193.13 million and $1,193.7 million as of ~~March~~June 3130, 2026 and December 31, 2025, respectively. Net losses of $1811.82 million and $30.0 million related to these contracts ~~was~~were recorded as a component of other (income) expense, net for the three and six months ended ~~March~~June 3130, 2026, compared to net gains of $727.7 million and $35.4 million, respectively, in the prior year comparative ~~period~~periods.

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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(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~~June 3130, 2026		As of December 31, 2025
Cash Flow Hedging Instruments:
Asset derivative instruments	Other current assets	$	1217.20	$	0.1
	Investments and other assets	57.97		0.4
Liability derivative instruments	Accrued expense and other	12(4.26)		54.0
	Other long-term liabilities	—		2.2
Other Derivative Instruments:
Asset derivative instruments	Other current assets	64.96		9.9
Liability derivative instruments	Accrued expense and other	26(21.09)		2.7


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 $~~2,998.~~3.1 billion ~~million~~ and $2~~,931~~.29 billion ~~million~~ as of ~~March~~June 3130, 2026 and December 31, 2025, respectively. For the three and six months ended ~~March~~June 3130, 2026 ~~and 2025~~, depreciation expense totaled approximately $67.9 million and $71135.48 million, respectively, compared to $66.9 million and $138.3 million, respectively, in the prior year comparative periods.


Note 12:			Indebtedness

2026 Term Loan Credit Agreement

In connection with our acquisition of Apellis we entered into a $2.0 billion term loan credit agreement. On the closing date of the Apellis acquisition we drew $2.0 billion from the 2026 Term Loan, comprised of a $1.0 billion floating rate 364-day tranche and a $1.0 billion floating rate two-year tranche. As of June 30, 2026, we had $1.8 billion outstanding under the term loan credit agreement, of which $800.0 million was outstanding under the 364-day tranche and $1.0 billion outstanding under the two-year tranche.

2025 Senior Notes

On May 12, 2025, we issued senior unsecured notes for an aggregate principal amount of $1.75 billion, consisting of the following:

•$400.0 million of 5.050% Senior Notes due January 15, 2031, valued at 99.981% of par;

•$650.0 million of 5.750% Senior Notes due May 15, 2035, valued at 99.924% of par; and

•$700.0 million of 6.450% Senior Notes due May 15, 2055, valued at 99.657% of par.

Our 2025 Senior Notes are senior unsecured obligations and may be redeemed at our option at any time at 100% of the principal amount plus accrued interest and, until a specified period before maturity, a specified make-whole amount. Our 2025 Senior Notes contain a change-of-control provision that, under certain circumstances, may require us to purchase our 2025 Senior Notes at a price equal to 101% of the principal amount plus accrued and unpaid interest to the date of repurchase.

We incurred approximately $13.9 million of costs associated with this offering which have been recorded as a reduction to the carrying amount of the debt on our condensed consolidated balance sheets. These costs will be amortized as additional interest expense using the effective interest rate method over the period from issuance ~~through maturity. The discounts will be amortized as additional interest expense over the period from issuance through maturity using the effective interest rate method.~~

Interest on our 2031 Senior Notes is payable January 15 and July 15 of each year, commencing January 15, 2026. Interest on our 2035 Senior Notes and 2055 Senior Notes is payable May 15 and November 15 of each year, commencing on November 15, 2025.33

4.050% Senior Notes due September 15, 2025

On September 15, 2015, we issued $1.75 billion aggregate principal amount of 4.050% Senior Notes due September 15, 2025, at 99.764% of par. In June 2025 we used the net proceeds from the sale of our 2025 Senior Notes to redeem our 4.050% Senior Notes due September 15, 2025, prior to maturity. No gain or loss was recognized upon redemption.

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through maturity. The discounts will be amortized as additional interest expense over the period from issuance through maturity using the effective interest rate method.

4.050% Senior Notes due September 15, 2025

2024 Revolving Credit Facility

In August 2024 we entered into a $1.5 billion, five-year senior unsecured revolving credit facility under which we are permitted to draw funds for working capital and general corporate purposes. The terms of the revolving credit facility include a financial covenant that requires us not to exceed a maximum consolidated leverage ratio. We borrowed $400.0 million under our revolving credit facility during the second quarter of 2026 and this borrowing was repaid in full in June 2026. As of June 30, 2026 and December 31, 2025, we had no outstanding borrowings and were in compliance with all covenants under this facility.


Note 13:			Equity

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, 2026
	For the Three Months Ended June 30, 2026
(In millions)	Unrealized Gains (Losses) on Securities Available for Sale, Net of Tax		Unrealized Gains (Losses) on Cash Flow Hedges,Net of Tax		Unrealized Gains (Losses) on Pension Benefit Obligation, Net of Tax		CurrencyTranslation Adjustments,Net of Tax		Total
Balance, December 31, 2025	$	0.2	$	(58.9)	$	(9.4)	$	(113.9)	$	(182.0)
Other comprehensive income (loss) before reclassifications	(1.8)		31.9		(0.5)		(8.5)		21.1
Amounts reclassified from AOCI	—		20.7		—		—		20.7
Net current period other comprehensive income (loss)	(1.8)		52.6		(0.5)		(8.5)		41.8
Balance, March 31, 2026	$	(1.6)	$	(6.3)	$	(9.9)	$	(122.4)	$	(140.2)
Other comprehensive income (loss) before reclassifications	0.6		6.6		(0.3)		(3.6)		3.3
Amounts reclassified from AOCI	1.0		8.2		—		—		9.2
Net current period other comprehensive income (loss)	1.6		14.8		(0.3)		(3.6)		12.5
Balance, June 30, 2026	$	—	$	8.5	$	(10.2)	$	(126.0)	$	(127.7)
	For the Six Months Ended June 30, 2026
(In millions)	Unrealized Gains (Losses) on Securities Available for Sale, Net of Tax		Unrealized Gains (Losses) on Cash Flow Hedges,Net of Tax		Unrealized Gains (Losses) on Pension Benefit Obligation, Net of Tax		CurrencyTranslation Adjustments,Net of Tax		Total
Balance, December 31, 2025	$	0.2	$	(58.9)	$	(9.4)	$	(113.9)	$	(182.0)
Other comprehensive income (loss) before reclassifications	(1.2)		38.5		(0.8)		(12.1)		24.4
Amounts reclassified from AOCI	1.0		28.9		—		—		29.9
Net current period other comprehensive income (loss)	(0.2)		67.4		(0.8)		(12.1)		54.3
Balance, June 30, 2026	$	—	$	8.5	$	(10.2)	$	(126.0)	$	(127.7)

	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		CurrencyTranslation 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)

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	For the Three Months Ended June 30, 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, March 31, 2025	$	(6.2)	$	(16.2)	$	(152.1)	$	(174.5)
Other comprehensive income (loss) before reclassifications	(120.4)		0.6		41.6		(78.2)
Amounts reclassified from AOCI	14.6		—		—		14.6
Net current period other comprehensive income (loss)	(105.8)		0.6		41.6		(63.6)
Balance, June 30, 2025	$	(112.0)	$	(15.6)	$	(110.5)	$	(238.1)

	For the Six Months Ended June 30, 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		Total
Balance, December 31, 2024	$	51.6	$	(16.6)	$	(171.2)	$	(136.2)
Other comprehensive income (loss) before reclassifications	(167.9)		1.0		60.7		(106.2)
Amounts reclassified from AOCI	4.3		—		—		4.3
Net current period other comprehensive income (loss)	(163.6)		1.0		60.7		(101.9)
Balance, June 30, 2025	$	(112.0)	$	(15.6)	$	(110.5)	$	(238.1)

The following table summarizes the amounts reclassified from AOCI:

(In millions)	Amounts Reclassified from AOCI				~~Income Statement Location~~				Income Statement Location
	For the Three Months Ended March 31,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
	2026		2025		2026		2025
Gains (losses) on cash flow hedges	$	(24.3)	$	10.9					Revenue
Gains (losses) on securities available for sale	$	(1.2)	$	—	$	(1.2)	$	—	Other (income) expense, net
	0.7		0.7						Operating expense
	0.2		—		0.2		—		Income tax (benefit) expense
	—		(0.1)						Other (income) expense, net
Gains (losses) on cash flow hedges	$	(9.2)	$	(22.9)	$	(33.5)	$	(12.0)	Revenue
	2.9		(1.2)						Income tax (benefit) expense
	(0.2)		6.6		0.5		7.3		Operating expense
Total reclassifications, net of tax	$	(20.7)	$	10.3
	—		(0.1)		—		(0.2)		Other (income) expense, net
	1.2		1.8		4.1		0.6		Income tax (benefit) expense
Total reclassifications, net of tax	$	(9.2)	$	(14.6)	$	(29.9)	$	(4.3)

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Note 14:			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,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Numerator:
Net income attributable to Biogen Inc.	$	~~319~~97.5	$	~~240~~634.58	$	417.0	$	875.3
Denominator:
Weighted average number of common shares outstanding	147.27		146.15		147.4		146.3
Effect of dilutive securities:
Time-vested restricted stock units	1.0.8		0.52		1.0		0.3
Performance stock units settled in stock	0.2		—		0.2		0.1
Dilutive potential common shares	1.20		0.52		1.2		0.4
Shares used in calculating diluted earnings per share	148.47		146.67		148.6		146.7

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


Note 15:			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,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Research and development	$	3432.83	$	3230.1	$	67.1	$	62.2
Selling, general and administrative	5348.0		5248.0		101.0		100.0
Subtotal	8780.83		8478.1		168.1		162.2
Capitalized share-based compensation costs	(3.80)		(3.12)		(6.8)		(6.3)
Share-based compensation expense included in total cost and expense	8477.03		8174.09		161.3		155.9
Income tax effect	(1615.52)		(1614.09)		(31.7)		(30.9)
Share-based compensation expense included in net income attributable to Biogen Inc.	$	6762.51	$	6560.0	$	129.6	$	125.0

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

	For the Three Months Ended March 31,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Time-vested restricted stock units	$	7066.96	$	6660.16	$	137.5	$	126.7
Performance stock units settled in stock	1311.38		1315.60		25.1		28.6
Employee stock purchase plan	31.69		31.56		5.5		5.1
Stock options	—		0.9		—		1.8
Subtotal	8780.83		8478.1		168.1		162.2
Capitalized share-based compensation costs	(3.80)		(3.12)		(6.8)		(6.3)
Share-based compensation expense included in total cost and expense	$	8477.03	$	8174.09	$	161.3	$	155.9

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Note 16:			Income Taxes

Tax Rate

For the three and six months ended ~~March~~June 3130, 2026 ~~and 2025~~, our effective tax rate was 1526.4% and 2218.3%, respectively, compared to 14.7% and 17.0%, respectively, in the prior year comparative periods. The ~~decrease~~increase in our effective tax rate for the three months ended June 30, 2026 was ~~partially~~primarily driven by ~~favorable~~non-deductible ~~impacts~~expenses ofrelated to our Apellis acquisition and, to a ~~current~~lesser ~~year~~extent, ~~settlement~~the favorable deferred tax impacts of adecreases in foreign ~~tax~~withholding ~~audit~~taxes ~~and~~recorded in the ~~vesting~~second quarter of ~~certain~~2025. ~~share~~The ~~based~~six ~~awards~~months ended June 30, ~~partially~~2026, ~~offset~~compared byto the ~~higher~~same ~~rate~~period in 2025, also reflects favorable impacts of ~~tax~~a oncurrent ~~NCTI~~year ~~due~~settlement toof a foreign tax audit and the ~~OBBBA~~vesting ~~enactment~~of certain share-based awards.

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 2022 or state, local or non-U.S. income tax examinations for years before 2013.

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.

For additional information on our income taxes, please read Note 17, Income Taxes, to our consolidated financial statements included in our 2025 Form 10-K.


Note 17:			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,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Interest income	$	(3725.93)	$	(2332.93)	$	(63.2)	$	(56.2)
Interest expense	6782.63		6072.06		149.9		132.6
(Gains) losses on investments, net	(2241.36)		35(5.63)		(63.9)		30.3
Litigation related expense	4(0.74)		35.02		4.3		8.2
Foreign exchange (gains) losses, net	6.5		(310.8)4		13.0		6.6
Other, net	1(3.10)		(21.59)		(1.9)		(4.4)
Total other (income) expense, net	$	1918.75	$	6848.47	$	38.2	$	117.1

The (gains) losses on investments, net, as reflected in the table above, relate to debt securities, 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,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Net (gains) losses recognized on equity securities	$	(2242.38)	$	35(5.63)	$	(65.1)	$	30.3
Less: Net (gains) losses realized on equity securities	~~(3.2)~~—		~~(5.4)~~—		(3.2)		(5.4)
Net unrealized (gains) losses recognized on equity securities	$	(1942.18)	$	41(5.03)	$	(61.9)	$	35.7

The net unrealized gains recognized during the three months ended ~~March~~June 3130, 2026, primarily reflect an increase in the aggregate fair value of our investment in Denali common stock of approximately $1946.27 million.

The net unrealized losses recognized during the three months ended March 31, 2025, primarily reflect a decrease in the aggregate fair value of our investment 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, which was later disposed of during the third quarter of 2025.37

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The net unrealized gains recognized during the three months ended June 30, 2025, primarily reflect an increase in the aggregate fair value of our investments in Sage and Denali common stock of approximately $10.1 million. Sage was later disposed of during the third quarter of 2025.

The net unrealized gains recognized during the six months ended June 30, 2026, primarily reflect an increase in the aggregate fair value of our investment in Denali common stock of approximately $65.9 million.

The net unrealized losses recognized during the six months ended June 30, 2025, primarily reflect a decrease in the aggregate fair value of our investments in Denali common stock of approximately $45.7 million, partially offset by an increase in the fair value of Sage common stock of approximately $23.0 million. Sage was later disposed of during the third quarter of 2025.

Other Current Assets

Other current assets includes prepaid taxes of $~~661~~648.69 million and $693.6 million as of ~~March~~June 3130, 2026 and December 31, 2025, respectively.

Accrued Expense and Other

Accrued expense and other consists of the following:

(In millions)	As of ~~March~~June 3130, 2026		As of December 31, 2025
Revenue-related reserves for discounts and allowances	$	~~961~~980.12	$	1,000.4
Employee compensation and benefits	~~192~~391.53		375.8
Collaboration expense	~~353~~198.58		280.0
Royalties and licensing fees	~~308~~337.58		302.4
Other	~~731~~718.2		844.0
Total accrued expense and other	$	2,~~546~~626.83	$	2,802.6

For additional information on our acquisition of Apellis, please read Note 2, Acquisitions, to these condensed consolidated financial statements.

Other Long-term Liabilities

Other long-term liabilities were $~~787~~820.19 million and $748.5 million as of ~~March~~June 3130, 2026 and December 31, 2025, respectively, and included accrued income taxes totaling $~~174~~177.25 million and $166.4 million, respectively.


Note 18:			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, follicular lymphoma and lupus nephritis; 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

Under our collaboration with Genentech, we are entitled to a tiered share of co-promotion operating profits and losses of RITUXAN in the U.S., as summarized in the table below. 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.

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GAZYVA

The Roche Group and its sub-licensees maintain sole responsibility for the development, manufacture and commercialization of GAZYVA and we are entitled to a tiered share of co-promotion operating profits and losses 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.

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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

Under our collaboration with Genentech, 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. The commercialization of COLUMVI does not impact the percentage of the co-promotion profits we receive for RITUXAN, LUNSUMIO or GAZYVA.

Profit-sharing Formulas

RITUXAN and LUNSUMIO Profit Share

Our current pre-tax 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. 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	%

In March 2023 the First Threshold Date was achieved when U.S. gross sales of GAZYVA within a consecutive 12-month period reached $500.0 million. As a result, beginning in April 2023 the pre-tax profit share for RITUXAN and LUNSUMIO has been 35.0%. The Second Threshold Date would be achieved on the first date in any calendar year in which U.S. gross sales of LUNSUMIO have reached $350.0 million.

GAZYVA Profit Share

Our current pre-tax profit-sharing formula for GAZYVA provides for a 35.0% share of operating profits earned in the U.S. in each calendar year.

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 2025 Form 10-K.

~~Ionis Pharmaceuticals, Inc.~~39

2017 SMA Collaboration Agreement

In December 2017 we entered into a collaboration agreement with Ionis to identify new ASO drug candidates for the potential treatment of SMA. Under this agreement, we have options to license therapies arising out of this collaboration and will be responsible for the development and commercialization of such therapies.

In December 2021 we exercised our option with Ionis and obtained a worldwide, exclusive, royalty-bearing license to develop and commercialize salanersen (BIIB115), an investigational ASO in development for SMA.

We may pay Ionis up to $155.0 million in additional development and regulatory milestone payments related to salanersen, including a $45.0 million milestone payment due upon the initiation of a Phase 3 trial. Upon commercialization, we may also pay Ionis up to $400.0 million in additional performance-based milestone payments and tiered royalties on potential net sales of such therapies ranging from the mid-teens to high-twenties percentages.

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Ionis Pharmaceuticals, Inc.

2018 Ionis Agreement

In the second quarter of 2026 we exercised our option with Ionis and obtained a worldwide, exclusive, royalty-bearing license to develop and commercialize a pre-clinical therapy under this agreement. In connection with the option exercise, we made a payment of $15.0 million to Ionis, which was recorded in acquired in-process research and development, upfront and milestone expense within our consolidated statements of income for the three and six months ended June 30, 2026.

2017 SMA Collaboration Agreement

In the second quarter of 2026 we recognized and paid a $45.0 million milestone payment due upon the initiation of a Phase 3 trial in salanersen, which was recorded in acquired in-process research and development, upfront and milestone expense within our consolidated statements of income for the three and six months ended June 30, 2026. Additionally, we may pay Ionis up to $110.0 million in additional development and regulatory milestone payments related to this program. Upon commercialization, we may also pay Ionis up to $400.0 million in additional performance-based milestone payments and tiered royalties on potential net sales of such therapies ranging from the mid-teens to high-twenties percentages.

For additional information on our collaboration arrangements with Ionis, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in our 2025 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 FDA granted traditional approval of LEQEMBI in July 2023. 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), Australia (September 2025), China (January 2024), Japan (September 2023) and other international markets. LEQEMBI monthly IV maintenance dosing for the treatment of early Alzheimer's disease was approved in the U.S. and China in January 2025 and September 2025, respectively, and LEQEMBI subcutaneous autoinjector (IQLIK) for weekly maintenance dosing and initiation dosing was approved in the U.S. in August 2025 and July 2026, respectively.

All costs, including research, development, sales and marketing expense, are shared equally between us and Eisai. We also 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.

Subject to the limitations in the LEQEMBI Collaboration Agreement, Eisai has final decision-making authority on all matters relating to the collaboration and serves as the lead of LEQEMBI development and regulatory submissions globally. We co-commercialize and co-promote LEQEMBI with Eisai. The LEQEMBI Collaboration Agreement provides that each commercialization plan shall allocate the responsibilities for the activities under the plan in an equitable fashion taking into account Biogen's and Eisai's respective capabilities and ~~provides~~provide a meaningful role for each party.

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:~~40

	For the Three Months Ended March 31,
(In millions)	2026		2025
Total development expense incurred by the collaboration related to the advancement of LEQEMBI	$	69.3	$	52.6
Biogen's share of the LEQEMBI Collaboration development expense reflected in research and development expense in our condensed consolidated statements of income	34.6		26.3
Total sales and marketing expense incurred by the LEQEMBI Collaboration	169.5		177.7
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	84.7		88.8

Amounts receivable from Eisai related to the agreements discussed above were approximately $7.0 million and $90.2 million as of March 31, 2026 and December 31, 2025, respectively. Amounts payable to Eisai related to the agreements discussed above were approximately $85.4 million and $95.5 million as of March 31, 2026 and December 31, 2025, 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 2025 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.

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


	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Total development expense incurred by the collaboration related to the advancement of LEQEMBI	$	61.5	$	54.9	$	130.8	$	107.5
Biogen's share of the LEQEMBI Collaboration development expense reflected in research and development expense in our condensed consolidated statements of income	30.8		27.5		65.4		53.8
Total sales and marketing expense incurred by the LEQEMBI Collaboration	155.2		171.2		324.7		348.9
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	77.6		85.7		162.3		174.5

Amounts receivable from Eisai related to the agreements discussed above were approximately $134.1 million and $90.2 million as of June 30, 2026 and December 31, 2025, respectively. Amounts payable to Eisai related to the agreements discussed above were approximately $92.5 million and $95.5 million as of June 30, 2026 and December 31, 2025, respectively.

UCB

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,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Total UCB collaboration development expense	$	29.43	$	2117.8	$	58.7	$	39.6
Biogen's share of the UCB collaboration development expense reflected in research and development expense in our condensed consolidated statements of income	14.76		108.9		29.3		19.8

Supernus Pharmaceuticals, Inc. (previously 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. In July 2025 Sage was acquired by Supernus. ZURZUVAE was approved in the U.S. in August 2023 and in the E.U. in September 2025.

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 Supernus potential tiered royalties in the high-teens to low-twenties percentages.

We share 50.0% of the net collaboration results in the U.S. with Supernus, which are recognized in collaboration profit sharing/(loss reimbursement) in our condensed consolidated statements of income. For the three and six months ended ~~March~~June 3130, 2026 ~~and 2025~~, we recognized net profit-sharing expense of approximately $1723.09 million and $1040.19 million, respectively, to reflect Supernus' 50.0% share of the net collaboration results, compared to net profit-sharing expense of approximately $17.8 million and $27.9 million, respectively, in the Uprior year comparative periods.S.

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

	For the Three Months Ended March 31,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Total Supernus collaboration development expense	$	1.2	$	21.45	$	2.4	$	3.9
Biogen's share of the Supernus collaboration development expense reflected in research and development expense in our condensed consolidated statements of income	0.6		10.28		1.2		2.0
Total sales and marketing expense incurred by the Supernus collaboration	4753.53		4345.57		100.8		89.2
Biogen's share of the Supernus 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	2326.7		2122.79		50.4		44.6

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.

In May 2026 Biogen and Denali announced topline results from the Phase 2b LUMA study evaluating BIIB122, which showed that BIIB122 did not meet its primary and secondary endpoints. Based on these results we and Denali will discontinue development of BIIB122 in idiopathic Parkinson's disease.

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

	For the Three Months Ended March 31,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Total Denali collaboration development expense	$	105.35	$	12.81	$	15.8	$	24.9
Biogen's share of the Denali collaboration development expense reflected in research and development expense in our condensed consolidated statements of income	63.23		7.72		9.5		14.9

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. Zorevunersen dosed its first patient in August 2025, advancing zorevunersen to a global Phase 3 trial.

35Under 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.

In connection with the closing of this transaction we made an upfront payment of $165.0 million to Stoke, which was recognized in acquired in-process research and development, upfront and milestone expense within our condensed consolidated statements of income for the six months ended June 30, 2025. We may also pay Stoke potential development and commercial milestone payments of up to $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.

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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.

In connection with the closing of this transaction we made an upfront payment of $165.0 million to Stoke, which was recognized in 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 potential development and commercial milestone payments of up to $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.

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

	For the Three Months Ended March 31,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Total Stoke collaboration development expense	$	1214.23	$	38.9	$	26.5	$	12.8
Biogen's share of the Stoke collaboration development expense reflected in research and development expense in our condensed consolidated statements of income	34.73		1.2.6		8.0		3.8

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. The transfer of commercialization rights for BYOOVIZ and OPUVIZ in the U.S. and Canada back to Samsung Bioepis was completed as of December 31, 2025.

In October 2025 we completed the sale of our remaining commercial rights to BYOOVIZ and OPUVIZ in Europe. Samsung Bioepis ~~will~~has ~~have~~ full responsibility for commercialization of BYOOVIZ upon the transfer of commercial rights from Biogen back to Samsung Bioepis, which became effective as of January 2026.

We reflected revenue on sales of BYOOVIZ to third parties in product revenue, net in our condensed consolidated statements of income and recorded 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.

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.

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.

36We 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 and six months ended June 30, 2026, we recognized net profit-sharing expense of approximately $44.9 million and $102.1 million, respectively, to reflect Samsung Bioepis' 50.0% sharing of the net collaboration profits, compared to net profit-sharing expense of approximately $57.2 million and $105.2 million, respectively, in the prior year comparative periods.

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 $3.5 million and $4.4 million as of June 30, 2026 and December 31, 2025, respectively. Amounts payable to

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WeSamsung ~~share~~Bioepis ~~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~~agreements ~~months~~discussed ~~ended~~above ~~March~~were ~~31,~~zero ~~2026~~ and ~~2025, we recognized net profit-sharing expense of~~ approximately $5742.27 million ~~and~~as ~~$48.0~~of ~~million,~~June ~~respectively~~30, to2026 ~~reflect~~and ~~Samsung~~December ~~Bioepis'~~31, ~~50.0%~~2025, ~~sharing of the net collaboration profits~~respectively.

Other Services

Amounts receivable from Samsung Bioepis related to the agreements discussed above were approximately $4.7 million and $4.4 million as of March 31, 2026 and December 31, 2025, respectively. Amounts payable to Samsung Bioepis related to the agreements discussed above were approximately $154.4 million and $42.7 million as of March 31, 2026 and December 31, 2025, 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 2025 Form 10-K.

Sobi

As part of our acquisition of Apellis, we have a collaboration and license agreement with Sobi to jointly develop and commercialize pegcetacoplan for use systemically or for local non-ophthalmological administration. Under the agreement, we have commercialization rights for EMPAVELI in the U.S. and Sobi has exclusive rights to commercialize pegcetacoplan as ASPAVELI in the rest of the world.

We supply pegcetacoplan to Sobi for development and for commercialization outside of the United States in accordance with a supply agreement between the parties.

Pursuant to the terms of our collaboration and license arrangement, as amended by a buy-down agreement entered into in July 2025 which reduces Sobi's royalty obligations by 90% subject to a defined cap, we are eligible to receive tiered royalties in the low single digits on net sales of ASPAVELI outside of the United States. If the defined cap is exceeded in a future period, the royalty terms in the original agreement will be reinstated, and we will earn royalties ranging from the high teens to high twenties on such net sales.

For the three and six months ended June 30, 2026, we recognized approximately $13.3 million in revenues from Sobi related to the agreements above, which are reflected as a component of contract manufacturing, royalty and other revenue in our condensed consolidated statements of income.

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.

~~Other~~Alteogen Inc.

~~For~~In ~~the three months ended~~ March ~~31,~~ 2026 ~~and~~we ~~2025,~~entered weinto ~~recorded~~an ~~approximately~~exclusive ~~$34.0 million~~license ~~and~~agreement ~~less~~with ~~than~~Alteogen $1Inc.~~0 million,~~ ~~respectively,~~to asenable ~~acquired~~the ~~in-process research and~~ development, ~~upfront~~of ~~and~~a ~~milestone~~subcutaneous ~~expense~~formulation ~~in our condensed consolidated statements~~ of ~~income~~two ~~related~~biologics tousing ~~other~~Alteogen's ~~research~~ALT-B4 ~~and~~hyaluronidase ~~discovery related arrangements~~technology.

In connection with the closing of this transaction we accrued an upfront payment of $20.0 million to Alteogen, which was recognized in acquired in-process research and development, upfront and milestone expense within our condensed consolidated statements of income for the six months ended June 30, 2026 and was paid during the second quarter of 2026.

Alteogen will also be eligible to receive a $10.0 million option payment if a second program is selected for development, as well as potential development, regulatory and commercial milestone payments and tiered royalties in the mid-single digit percentages on net sales of any combination products resulting from the collaboration.

Alloy Therapeutics, Inc.

In March 2026 we entered into a collaboration and license agreement with Alloy Therapeutics Inc. for the use of Alloy’s novel and proprietary AntiClastic ASO Platform. Through this collaboration, we plan to apply the platform to advance antisense therapeutics against multiple targets.

In connection with the closing of this transaction we accrued an upfront payment of $12.0 million to Alloy, which was recognized in acquired in-process research and development, upfront and milestone expense within our condensed consolidated statements of income for the six months ended June 30, 2026 and was paid during the second quarter of 2026.

Alloy will also be eligible to receive potential milestone payments and tiered royalties on any products resulting from the collaboration.

Royalty Pharma Funding Arrangement

In February 2025 we entered into a funding agreement with Royalty Pharma under which we received $200.0 million in 2025 and $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. This funding is being recognized as a reduction to research and development expense within our condensed consolidated statements of income, proportionate to the related expense. For the three months ended March 31, 2026 and 2025, we received $25.0 million and $50.0 million, respectively, from Royalty Pharma, which we recorded as reductions to research and development expense within our condensed consolidated statements of income. The final payment related to the funding agreement of $25.0 million was received in April 2026.

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 $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.44

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

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recognized by us as an obligation to perform contractual services. This funding was recognized as a reduction to research and development expense within our condensed consolidated statements of income, proportionate to the related expense. For the three and six months ended June 30, 2026, we received $25.0 million and $50.0 million, respectively, from Royalty Pharma, compared to $50.0 million and $100.0 million, respectively, in the prior year comparative periods. All funding has been received and the funding period has concluded as of June 30, 2026.

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

MorphoSys AG

As part of our acquisition of HI-Bio in July 2024, we acquired HI-Bio's pre-existing in-license commitments under third-party agreements with MorphoSys (a wholly-owned subsidiary of Novartis), which included tiered royalties on potential future net sales ranging from high-single digit to mid-teen percentages, as well as potential development, regulatory and commercial milestone payments of up to $130.0 million, $230.0 million and $640.0 million, respectively. These amounts included 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, which were earned during the first and second quarters of 2025 and recorded within acquired in-process research and development, upfront and milestone expense.

In April 2026 we entered into a definitive agreement with TJ Bio, where we assumed regulatory and sales milestone obligations under a pre-existing agreement between TJ Bio and MorphoSys and may pay MorphoSys tiered royalties on potential net sales of felzartamab in the greater China region. ~~For additional information on TJ Bio, please read Note 22, Subsequent Events, to these condensed consolidated financial statements.~~

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 paid in April 2025.Other

~~During~~For the ~~second~~three ~~quarter~~and ofsix ~~2025~~months weended ~~accrued~~June a30, ~~milestone~~2026, ~~payment~~we ~~due~~recorded toapproximately ~~MorphoSys of~~ $304.0 million ~~upon~~and ~~the~~$6.0 ~~first~~million, ~~patient dosed in a Phase 3 clinical trial of felzartamab for the treatment of IgAN~~respectively, ~~which~~as ~~was recorded within~~ acquired in-process research and development, upfront and milestone expense in our condensed consolidated statements of income related to other research and discovery related arrangements, compared to $16.6 million and ~~paid~~$17.3 million, respectively, in ~~July~~the ~~2025~~prior year comparative periods.


Note 19:			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~~June 3130, 2026 and December 31, 2025, the carrying value of our investments in certain biotechnology companies representing potential unconsolidated variable interest entities totaled $48.4 million and $49.8 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 2025 Form 10-K.

~~Note 20: Litigation~~45

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 2025 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.

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~~enforceability~~Note 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 position20: ~~(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.~~Litigation

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

We and certain current and former officers are defendants in ~~three~~four securities actions pending in the District Court, one filed byin November 2020 (Nadia Shash was named lead plaintiff and named in an amended complaint along with named plaintiff Amjad Khan in ~~November~~April ~~2020~~2021), 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 in byMay 2024 (Francis Clarity Stokes was named lead plaintiff and named along with Thomas Allen Gray ~~and~~in ~~Frances~~an ~~Clarity~~amended ~~Stokes~~complaint filed in ~~May~~December 2024), which relates to statements about LEQEMBI, TECFIDERA and VUMERITY, and one filed in August 2023 (Ray Peleckas and the Michigan Laborers’ Pension Fund were appointed lead plaintiffs and named in an amended complaint filed in October 2023), which relates to statements made by Apellis Pharmaceuticals, Inc. about SYFOVRE. All allege violations of federal securities laws under 15 U.S.C. §78j(b) and §78t(a) and 17 C.F.R. §240.10b-55c and seek declarations of the actions as class actions and monetary relief. In March 2026 the District Court dismissed the action brought by Thomas Allen Gray and Frances Clarity Stokes and they ~~have~~ appealed. In June 2026 Thomas Allen Gray requested voluntary dismissal of his appeal but the appeal by lead plaintiff Frances Clarity Stokes continues. In April 2026 the parties in the action brought by the Oklahoma Firefighters Pension and Retirement System reached an agreement in principle to settle the action and the District Court preliminarily approved the settlement in June 2026 and set a hearing on final approval for September 29, 2026. In March 2025 the District Court dismissed the action brought by Michigan Laborers' Pension Fund and Ray Peleckas. They appealed and the appeal is pending.

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 (Booth) in February 2022, one filed by Elaine Wang (Wang) in July 2022, one filed by Jonathan Blaufarb (Blaufarb I) in July 2024, one filed by Lawrence Hollin (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

IMRALDI is an adalimumab biosimilar manufactured by Samsung Bioepis that Biogen commercializes in Europe.

Fresenius Kabi has alleged infringement of national counterparts of its EP '3 145 488 Patent (the EP '488 Patent), including in Spain, Italy, France and Germany. 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 infringement of the French counterpart of the EP '488 Patent by a formulation of IMRALDI no longer commercialized in France. Fresenius Kabi alleges damages of approximately €19.1 million plus interest and costs. Biogen disputes infringement and the validity of the patent. Trial is set for June 2026.46

In May 2025 the Higher Regional Court of Düsseldorf, Germany held that a formulation of IMRALDI we no longer commercialize in Germany infringed the German counterpart of the EP '488 Patent, enjoined infringement and declared Fresenius Kabi's right to seek damages. Biogen has requested review of the decision by Germany's Federal Court of Justice and has challenged the validity of the patent in a separate proceeding.

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 providing MS patients with free medications and to charitable contributions to non-profit organizations that provide financial assistance to 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 in the U.S. District Court for the Northern District of California claiming that it was owed royalties on sales of TYSABRI that occurred after the expiration of a patent licensed by Genentech to Biogen. In November 2025 the court entered judgment against us for approximately $124.3 million. We appealed and the appeal is pending.

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Fresenius Kabi has alleged infringement of national counterparts of its EP '3 145 488 Patent (the EP '488 Patent), including in Spain, Italy, France and Germany, and has also threatened litigation in Switzerland. 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 infringement of the French counterpart of the EP '488 Patent by a formulation of IMRALDI no longer commercialized in France and alleging damages of approximately €19.1 million plus interest and costs. Biogen disputes infringement and challenges the validity of the patent. Trial was held in June 2026 and a decision is pending.

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 providing MS patients with free medications and making charitable contributions to non-profit organizations that provide financial assistance to MS patients. Humana alleges breach of contract, fraud and other claims under various state laws and seeks damages, attorneys' fees and costs.

Genentech Litigation

Antitrust Litigation

In October 2025 Local No. 1 Health Fund, the Mayor and City Council of Baltimore, Teamsters Local 237 Welfare Fund, Teamsters Local 237 Retirees' Benefit Fund, UFCW Local 1500 Welfare Fund, and Jacksonville Police Officers and Fire Fighters Health Insurance Trust filed an amended complaint against us in now consolidated proceedings in the U.S. District Court for the Northern District of Illinois (the Illinois federal court). The first complaint was filed in August 2024. The plaintiffs allege violations of federal antitrust laws including 15 U.S.C. §§ 1, 2 and 13(c), the Racketeer Influenced and Corrupt Organizations Act, 18 U.S.C. §1962(c) and of various state laws, based on allegations about our contracts with pharmacy benefit managers related to TECFIDERA and VUMERITY and other allegations. Plaintiffs seek declarations of the actions as class actions, monetary, declaratory and equitable relief, and attorneys' fees and costs.

In addition, in September 2025 Walgreen Co. and The Kroger Co. sued us in the Illinois federal court, alleging violations of 15 U.S.C. §§ 1 and 2 based on allegations about our contracts with pharmacy benefit managers related to TECFIDERA and VUMERITY and other allegations. They seek monetary, declaratory and equitable relief, and attorneys' fees and costs.

Neurimmune Litigation

In May 2025 we sued Neurimmune Holding AG and Neurimmune Subone AG (collectively, "Neurimmune") in the District Court seeking declaratory judgment and permanent injunctive relief regarding our rights under a terminated collaboration agreement related to aducanumab. In September 2025 Neurimmune counterclaimed for declaratory judgment, breach of contract and unfair competition under Massachusetts G.L. 93A and ~~seeking~~seeks monetary, declaratory and equitable relief and attorneys' fees and costs.

TECFIDERA E.U. Litigation

We have sued certain generic companies for damages for sales of generic versions of TECFIDERA in violation of our regulatory market protection, including Neuraxpharm Pharmaceuticals S.L., Neuraxpharm Netherlands B.V., Zaklady Farmaceutyczne Polpharma S.A., Sandoz B.V., Mylan Ireland Ltd. and Mylan B.V. in the District Court of Amsterdam Netherlands in November 2023; Sandoz A/S in the Danish Maritime and Commercial High Court in June 2024; and STADA Arzneimittel AG, STADA Nordic ApS, Sandoz A/S, Sandoz (Denmark) and Sandoz A/S (Finland), Glenmark Arzneimittel AG and Glenmark Pharmaceuticals Nordic AB in the Finnish Market Court in July 2024. All of these ~~parties have counterclaimed for damages based on our actions to enforce TECFIDERA's regulatory marketing protection.~~

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parties have counterclaimed for damages based on our actions to enforce TECFIDERA's regulatory marketing protection.

In September 2025 the European General Court annulled the May 2023 European Commission decision granting TECFIDERA an additional year of regulatory marketing protection extending until February 2025. We and the European Commission appealed and the appeal is pending.

In November 2025 the Technical Boards of Appeal of the European Patent Office revoked our EP 2 653 873 patent related to TECFIDERA, after which we stopped enforcing this patent and its national counterparts. Certain generic companies have filed claims ~~in the Danish Maritime and Commercial High Court~~ for ~~alleged~~ damages ~~due~~based toon injunctions we obtained prior to patent revocation,. ~~including~~Such ~~Sandoz~~claims ~~A/S~~have been filed in ~~October~~the ~~2025,~~Danish Maritime and Commercial High Court by Viatris ApS in January 2024, Glenmark Pharmaceuticals Nordic AB in July 2025, ~~and~~Sandoz A/S in October 2025, Neuraxpharm Sweden AB and Neuraxpharm Pharmaceuticals S.L. in February 2026 and in the Prague Municipal Court, Czechia, by Glenmark Pharmaceuticals s.r.o., Glenmark Pharmaceuticals Distribution s.r.o. and Zakłady Farmaceutyczne Polpharma S.A. in May 2026.

Germany Tax Matter

In December 2025 and January 2026 a German tax authority issued assessments against us of approximately €209.8 million including interest, which continues to accrue. We are challenging the assessments.

Other Matters

Government Investigations

In May 2024 the Italian Competition Authority informed us that it is investigating Biogen and other companies in relation to our biosimilar product BYOOVIZ.

In September 2025 we received a Civil Investigative Demand from the Louisiana Department of Justice for information regarding our policies relating to the purchase of drugs by healthcare organizations that are covered entities under Section 340B of the Public Health Service Act.

40In January 2026 we received a request for information regarding TECFIDERA from the European Commission Directorate-General for Competition. In July 2026 the Commission informed us that it has closed the matter.

In May 2026 the Italian Competition Authority announced that it is investigating Biogen in relation to our STRATIFY JCV assay.

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. In January 2026 we filed an amended complaint against Sandoz Inc. alleging infringement of U.S. Patent Nos. 10,233,245 and U.S. 11,292,845 and seeking damages. Trial against Sandoz Inc. is scheduled for April 2027.

Hatch-Waxman Act Litigation relating to SPINRAZA

In May and June 2026, Biogen filed patent infringement proceedings relating to SPINRAZA Orange-Book listed patents (U.S. Patent Nos. 9,926,559, 10,436,802 and 12,013,403) 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 Somerset Therapeutics, LLC, Somerset Pharma, LLC, Somerset Therapeutics Private Limited f/k/a Somerset Therapeutics Limited and Odin Pharmaceuticals, LLC (collectively, Somerset) and Cipla Ltd. and Cipla USA, Inc.

In June 2026, Biogen, Cold Spring Harbor Laboratory and Ionis Pharmaceuticals, Inc. filed patent infringement proceedings relating to additional SPINRAZA Orange-Book listed patents (U.S. Patent Nos. 8,361,977, 8,980,853 and 9,717,750) pursuant to the Hatch-Waxman Act in the U.S. District Court for the District of Delaware against Somerset.

Eisai Matter

In June 2025 we filed a request for arbitration in the International Court of Arbitration of the International Chamber of Commerce seeking adoption of a budget and commercialization plan for the European Territory that allocates commercialization activities to Biogen and Eisai in an equitable fashion taking into account our respective capabilities and provides a meaningful role for each party. A hearing is set for May 2027.

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In January 2026 we received a request for information regarding TECFIDERA from the European Commission Directorate-General for Competition.

TYSABRI Biosimilar Patent Matter

Eisai Matter

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 21:			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 2025 Form 10-K, contains additional information on our segment’s revenue and profits, including significant segment expense and other segment items.

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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,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026		2025
Total revenue	$	2,~~477~~736.80	$	2,~~431~~645.05	$	5,213.8	$	5,076.5
Less cost and expense:
Cost of sales, excluding amortization and impairment of acquired intangible assets:
Product cost of sales	~~478~~582.73		~~462~~415.20		1,061.0		877.2
Royalty cost of sales	~~182~~194.36		~~167~~190.10		376.9		357.1
Research and development:
Research and discovery	4041.56		4446.36		82.1		90.9
Early stage programs	6949.03		7251.49		118.3		124.3
Late stage programs	~~102~~119.58		4944.46		222.3		94.0
Marketed products	~~154~~151.28		8987.57		306.0		177.2
Other research and development costs(1)	~~172~~167.81		~~178~~168.52		339.9		346.7
Acquired in-process research and development, upfront and milestone expense	34164.0		~~200~~46.76		198.0		247.3
Selling, general and administrative	~~607~~709.37		~~572~~583.58		1,317.0		1,156.3
Other segment expense(2)	~~317~~458.03		~~353~~376.93		775.3		730.2
Net Income attributable to Biogen Inc.	$	~~319~~97.5	$	~~240~~634.58	$	417.0	$	875.3

(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.

~~Note 22: Subsequent Events~~50

TJ Biopharma Co., Ltd.

In April 2026 we entered into a definitive agreement with TJ Biopharma Co., Ltd. to acquire TJ Bio's exclusive rights to felzartamab in the greater China region. With this agreement, we will own exclusive worldwide rights to felzartamab.

Under the terms of this agreement we made an upfront payment of $100.0 million to TJ Bio, which will be recognized in acquired in-process research and development, upfront and milestone expense within our condensed consolidated statements of income during the second quarter of 2026.

Additionally, we assumed regulatory and sales milestone obligations under a pre-existing agreement between TJ Bio and MorphoSys and may pay MorphoSys tiered royalties on potential net sales of felzartamab in the greater China region.

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ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

The following discussion should be read in conjunction with our unaudited condensed consolidated financial statements (condensed consolidated financial statements) and the accompanying notes beginning on page 8 of this quarterly report on Form 10-Q and our audited consolidated financial statements and the accompanying notes included in our 2025 Form 10-K.

The results and operations of Apellis, along with the estimated fair values of the assets acquired and liabilities assumed in the Apellis acquisition, have been included in our condensed consolidated financial statements since the closing of the Apellis acquisition on May 14, 2026.

EXECUTIVE SUMMARY

INTRODUCTION

On May 14, 2026, we completed the acquisition of Apellis. As a result of this acquisition we acquired SYFOVRE for the treatment of geographic atrophy, or GA, an immune-mediated retinal disease; and EMPAVELI for the treatment of paroxysmal nocturnal hemoglobinuria, or PNH, a rare blood disorder, and C3 glomerulopathy, or C3G, and primary immune complex membranoproliferative glomerulonephritis, or primary IC-MPGN, in rare immune-mediated kidney diseases. For additional information on the acquisition of Apellis, please read Note 2, Acquisitions, to these condensed consolidated financial statements.

For additional information on our collaboration arrangements, please read Note 18, Collaborative and Other Relationships, to our condensed consolidated financial statements included in this report.

We seek to ensure an uninterrupted supply of medicines to patients around the world. To that end, we regularly review our manufacturing capacity, capabilities, processes and facilities. In order to support our future growth and drug development pipeline, we expanded our large molecule production capacity and built a large-scale biologics manufacturing facility in Solothurn, Switzerland. The Solothurn facility is operational and has been approved for the manufacture of LEQEMBI and TYSABRI. We believe that the Solothurn facility will support our anticipated near to mid-term needs for the manufacturing of biologic assets. The plant represents a significant increase in our overall manufacturing capacity. Additionally, we continue to invest to modernize, automate and support the capacity requirements for our pipeline and existing products at our existing manufacturing facilities in RTP, North Carolina. If we are unable to fully utilize our manufacturing facilities, we will incur additional excess capacity charges which would have a negative effect on our financial condition and results of operations.

In the longer term, our revenue growth will depend upon the successful clinical development, regulatory approval and launch of new commercial products as well as additional indications for our existing products, our ability to obtain and maintain patents and other rights related to our marketed products, assets originating from our research and development efforts and/or successful execution of external business development opportunities.

BUSINESS ENVIRONMENT

The biopharmaceutical industry and the markets in which we operate are intensely competitive. Many of our competitors are working to develop or have commercialized products similar to those we market. In addition, the commercialization of certain of our own approved products, products of our collaborators and pipeline product candidates may negatively impact future sales of our existing products.

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Our products and revenue streams continue to face increasing competition in many markets from the introduction of new originator therapies, generics, biosimilars of existing products and products approved under abbreviated regulatory pathways. Some of these products are likely to be sold at substantially lower prices than branded products. Accordingly, the introduction of such products as well as other lower-priced competing products has significantly reduced, and in the future may significantly reduce, both the price that we are able to charge for our products and the volume of products we sell, which can negatively impact our revenue. In addition, in some markets, when a generic or biosimilar version of one of our products is commercialized, it may be automatically substituted for our product and significantly reduce our revenue in a short period of time.

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Sales of our products depend, to a significant extent, on the availability and extent of adequate coverage, pricing and reimbursement from government health administration authorities, private health insurers and other organizations. When a new pharmaceutical product is approved, the availability of government and private reimbursement for that product may be uncertain, as is the pricing and the amount for which that product will be reimbursed.

~~Drug~~Our ~~prices~~future ~~are~~revenue ~~under~~growth ~~significant~~will ~~scrutiny~~depend inupon the ~~markets~~successful inclinical ~~which~~development, ~~our~~regulatory ~~products~~approval ~~are~~and ~~prescribed;~~launch ~~for~~of ~~example~~new ~~the~~commercial ~~IRA~~products ~~has~~as ~~certain~~well ~~provisions~~as ~~related~~additional toindications ~~drug~~for ~~pricing,~~our ~~including~~existing ~~the~~products, our ability ~~for the U.S. government~~ to ~~set~~obtain ~~prices~~and ~~for~~maintain ~~certain~~patents ~~drugs in Medicare. We expect drug pricing~~ and other ~~healthcare~~rights ~~costs~~related ~~will continue~~ to beour ~~subject~~marketed ~~to political and societal pressures on a global basis. As the policy environment remains dynamic~~products, weassets ~~will~~originating ~~continue~~from toour ~~monitor~~research ~~how uncertainty with respect to how the U.S.~~ and ~~foreign~~development ~~tariffs~~efforts and/or ~~the~~successful ~~U.S.~~execution ~~and~~of ~~international~~external ~~pricing may impact our~~ business indevelopment ~~the future~~opportunities.

~~Additionally,~~We ~~our~~seek ~~ability~~to ensure an uninterrupted supply of medicines to ~~set~~patients around the ~~price~~world. ~~for~~To that end, we regularly review our ~~products~~manufacturing ~~varies~~capacity, ~~significantly~~capabilities, ~~from~~processes ~~country~~and facilities. In order to ~~country~~support our future growth and drug development pipeline, aswe expanded our large molecule production capacity and built a ~~result~~large-scale biologics manufacturing facility in Solothurn, soSwitzerland. ~~can~~The ~~the~~Solothurn ~~price~~facility oris ~~reimbursement~~operational and has been approved for the manufacture of ~~our~~LEQEMBI ~~products~~and TYSABRI. ~~Governments~~We ~~may~~believe ~~use~~that athe ~~variety~~Solothurn offacility ~~cost-containment~~will ~~measures~~support our anticipated near to ~~control~~mid-term needs for the ~~cost~~manufacturing of ~~medicines,~~biologic ~~including~~assets. ~~price~~The ~~cuts~~plant represents a significant increase in our overall manufacturing capacity. Additionally, ~~mandatory~~we ~~rebates~~continue to invest to modernize, ~~value-based~~automate ~~pricing~~and support the capacity requirements for our pipeline and ~~reference~~existing ~~pricing~~products ~~(i.e.,~~at ~~referencing~~our ~~prices~~existing manufacturing facilities in ~~other~~RTP, ~~countries~~North ~~and~~Carolina. ~~using~~If ~~those~~we ~~reference~~are ~~prices~~unable to ~~set~~fully utilize our manufacturing facilities, we will incur additional excess capacity charges which would have a ~~price)~~negative effect on our financial condition and results of operations.

Our failure to obtain or maintain adequate coverage, pricing or reimbursement for our products could have an adverse effect on our business, reputation, revenue and results of operations, could curtail or eliminate our ability to adequately fund research and development programs for the discovery and commercialization of new products and/or could cause a decline or volatility in our stock price.

In addition to the impact of competition, pricing actions and other measures being taken worldwide designed to reduce healthcare costs and limit the overall level of government expenditures, our sales and operations could also be affected by other risks of doing business internationally, including the impact of public health epidemics on employees, the global economy and the delivery of healthcare treatments, geopolitical events, tariffs, supply chain disruptions, foreign currency exchange fluctuations, changes in intellectual property legal protections and changes in trade regulations and procedures.

For a detailed discussion on our business environment, please read Item 1. Business, in our 2025 Form 10-K. For additional information on our competition and pricing risks that could negatively impact our product sales, please read Item 1A. Risk Factors included in this report.

TECFIDERA

Multiple TECFIDERA generic entrants are now in North America, Brazil and the E.U. and have deeply discounted prices compared to TECFIDERA. The generic competition for TECFIDERA has significantly reduced our TECFIDERA revenue and we expect that TECFIDERA revenue will continue to decline. In November 2025 the Technical Boards of Appeal of the European Patent Office revoked our EP 2 653 873 patent related to TECFIDERA, after which we stopped enforcing this patent and its national counterparts.

For additional information, please read Note 20, Litigation, to our condensed consolidated financial statements included in this report.

TYSABRI

A biosimilar entrant of TYSABRI was approved in the U.S. and the E.U. in 2023. We expect the future sales of TYSABRI will continue to be adversely affected by the entrance of this biosimilar.

TECFIDERA

In November 2025 the Technical Boards of Appeal of the European Patent Office revoked our EP 2 653 873 patent related to TECFIDERA, after which we stopped enforcing this patent and its national counterparts. Multiple TECFIDERA generic entrants are now in North America, Brazil and the E.U. and have deeply discounted prices compared to TECFIDERA. The generic competition for TECFIDERA has significantly reduced our TECFIDERA revenue compared to prior periods, and we expect that TECFIDERA revenue will continue to decline.

For additional information, please read Note 20, Litigation, to our condensed consolidated financial statements included in this report.

BUSINESS UPDATE REGARDING MACROECONOMIC CONDITIONS AND OTHER POTENTIAL DISRUPTIONS

Significant portions of our business are conducted in Europe, Asia and other international geographies. Factors such as global health outbreaks, adverse weather events, geopolitical events or conflicts, tariffs, inflation, labor or raw material shortages and other supply chain disruptions could result in product shortages or other difficulties and delays or increased costs in manufacturing or distributing our products.

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material shortages and other supply chain disruptions could result in product shortages or other difficulties and delays or increased costs in manufacturing or distributing our products.

Economic conditions remain uncertain as markets continue to be impacted in part by continued inflationary pressures, higher interest rates, extreme weather events, global supply chain uncertainties and risks associated with geopolitical conflicts. Global supply chain disruptions, such as strikes, work stoppages, port congestion, port closures, trade restrictions, capacity constraints and other logistical problems, may affect our ability to do business.

INTERNATIONAL TRADE

Global conflicts or disputes and interruptions in international relationships, including tariffs, trade protection measures, economic embargoes, import or export licensing requirements and the imposition of trade sanctions or similar restrictions, may affect our ability to do business and the costs that we incur in providing products to our patients.

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In 2025 the U.S. imposed a series of tariffs on imports from nearly all countries, including tariffs pursuant to the IEEPA subject to certain exemptions. Trade-related tensions between the U.S. and China have also led to a series of tariffs and sanctions being imposed by the U.S. on imports from China and retaliatory tariffs imposed by China on U.S. imports, subject as well to exemptions.

Furthermore, in 2025, the U.S. reached a series of Framework Agreements with some countries and trading blocs including the E.U., Switzerland, the U.K., Japan and South Korea, carving U.S. tariff rates for certain import categories between 10.0% and 15.0%.

In February 2026 the U.S. Supreme Court issued a ruling striking down tariffs previously imposed under the IEEPA. The ultimate availability, timing and amount of any potential refunds of such tariffs remain highly uncertain and could be subject to further legal, regulatory and administrative developments. The amount of IEEPA tariff refunds, if any, that we ultimately recover may differ from the full amount we previously paid. Furthermore, any potential refunds or recoveries may be offset by refunds due to customers for payments made in connection with the IEEPA tariffs. As of this filing date, we have not recorded a receivable for any refund of IEEPA tariffs.

Following the Supreme Court's decision, the U.S. Administration ~~announced~~imposed ~~its~~a ~~intention~~10% tobaseline ~~impose~~tariff ~~other~~on ~~tariffs~~imports ~~under~~from ~~different~~nearly ~~authorities~~all ~~and~~countries, ~~introduced~~in ~~new~~addition to any existing non-IEEPA tariffs. The baseline tariff expired on ~~imports~~July ~~from~~24, ~~nearly~~2026. ~~all~~Effective ~~countries~~July 24, ~~imposing~~2026, athe U.S. Administration imposed new tariffs of 10.0% ~~baseline~~to ~~tariff~~12.5% inon ~~addition~~goods from approximately 60 economies under Section 301 of the Trade Act of 1974, subject to ~~any~~certain ~~existing~~exemptions, ~~non-IEEPA~~and ~~tariffs~~reduced rates for goods from certain economies where we have significant operations or commercial presence, such as the E.U. and Switzerland. There remains substantial uncertainty regarding the duration of existing and newly announced tariffs, potential changes or pauses to such tariffs, tariff levels and whether further additional tariffs or other retaliatory actions may be imposed, modified or suspended, and the impacts of such actions on our business.

The U.S. Secretary of Commerce previously initiated an investigation to determine the effects on the national security of imports of pharmaceuticals and pharmaceutical ingredients, including finished drug products, medical countermeasures, critical inputs such as active pharmaceutical ingredients, key starting materials and derivative products of those items, under Section 232 of the Trade Expansion Act of 1962. In April 2026 after the investigation concluded, the U.S. Administration issued a Proclamation imposing a 100% tariff on imports of patented pharmaceuticals, biologics and associated ingredients, subject to certain exemptions and reduced rates. The Proclamation tariffs are effective for certain categories on July 31, 2026, and others on September 29, 2026.

In June 2026, the EU Parliament published a list of tariffs’ exemptions for U.S. originating goods (including some pharmaceuticals) with an effective date of July 1, 2026, until December 31, 2029.

There is a high degree of uncertainty concerning what future steps countries and economic blocs will take in response to changes in global trade rules and economics.

We have a significant manufacturing presence in the U.S. While our portfolio is evolving, approximately three quarters of our 2025 U.S. product revenue was attributable to products that were largely manufactured in the U.S. However, we, and the biopharmaceutical industry, do utilize partners and production facilities located outside the U.S. for certain raw materials, ingredients, processes and components for our products and their delivery technologies. Engaging alternative suppliers may involve seeking additional regulatory approvals and incurring additional costs and risks associated with new suppliers. This may be costly in terms of time and resources needed or result in delays.

Key products that are currently manufactured primarily outside the U.S. are ~~TECFIDERA~~EMPAVELI, ~~VUMERITY~~LEQEMBI, TECFIDERA and ~~LEQEMBI~~VUMERITY. In 2024 we initiated a technology transfer process to enable us to manufacture LEQEMBI in the U.S., which was approved in January 2026.

Although certain starting materials for SKYCLARYS rely on a single supplier based in China, the manufacturing process, including active pharmaceutical ingredients and drug substance, is primarily conducted in the U.S.

We are working to mitigate potential exposure from tariffs across our network, and as of the date of this filing, we do not expect the tariffs currently applicable to our business to result in a material adverse effect on our operations in 2026. This is based on existing tariffs in place or potential tariffs as previously announced by the U.S. Administration, our manufacturing footprint and our inventory levels and market positioning. Should additional tariffs be enacted, our business could be impacted in the future and our results and operations could differ materially from our current expectations. We will continue to monitor the current and future global tariff landscape as it evolves.

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2026. This is based on existing tariffs in place or potential tariffs as previously announced by the U.S. Administration, our manufacturing footprint and our inventory levels and market positioning. Should additional tariffs be enacted, our business could be impacted in the future and our results and operations could differ materially from our current expectations. We will continue to monitor the current and future global tariff landscape as it evolves.

GEOPOLITICAL TENSIONS

The ongoing geopolitical tensions related to Russia's invasion of Ukraine and the military conflict in the Middle East and other global geopolitical developments have resulted in global business disruptions and economic volatility. For example, sanctions and other restrictions have been levied on the government and businesses in Russia. Although we do not have affiliates or employees in either Russia or Ukraine, we do provide various therapies to patients in Russia through a distributor. Government sanctions on the export of certain manufacturing materials to Russia may delay or limit our ability to get new products approved. The impact of the conflict on our operations and financial performance remains uncertain and will depend on future developments, including the severity and duration of the conflict between Russia and Ukraine, its impact on regional and global economic conditions and whether the conflict spreads or has effects on countries outside Ukraine and Russia.

We are closely monitoring ongoing geopolitical tensions in the Middle East, including the recent conflict involving the U.S., Israel and Iran, and the related regional instability. The ongoing geopolitical conflicts in the region could lead to significant disruption of fuel and energy supplies and increases in global fuel prices, which could heighten inflationary pressures, disrupt global supply chains and adversely impact the availability and pricing of raw materials. For example, our primary shipping method for resources and finished goods is through air freight. We will continue to evaluate and take actions to mitigate any potential impacts on our business, results of operations and financial condition. Although the long-term effects remain uncertain, this geopolitical conflict did not have any material effects on our results of operations for the three months ended March 31, 2026.53

WeTable will continue to monitor the ongoing conflict between Russia and Ukraine as well as the military conflict in the Middle East and other global geopolitical developments and assess any potential impacts on our business, supply chain, partners or customers, as well as any factors that could have an adverse effect on our results of operations. Revenue generated from sales in Russia and Ukraine represent less than 2.0% of total revenue for the three months ended March 31, 2026 and 2025. Additionally, revenue generated from sales in the broader Middle East region represents less than 3.0% of total revenue for the three months ended March 31, 2026 and 2025.Content

we do not have affiliates or employees in either Russia or Ukraine, we do provide various therapies to patients in Russia through a distributor. Government sanctions on the export of certain manufacturing materials to Russia may delay or limit our ability to get new products approved. The impact of the conflict on our operations and financial performance remains uncertain and will depend on future developments, including the severity and duration of the conflict between Russia and Ukraine, its impact on regional and global economic conditions and whether the conflict spreads or has effects on countries outside Ukraine and Russia.

We will continue to monitor the ongoing conflict between Russia and Ukraine as well as the military conflict in the Middle East and other global geopolitical developments and assess any potential impacts on our business, supply chain, partners or customers, as well as any factors that could have an adverse effect on our results of operations. Revenue generated from sales in Russia and Ukraine represent less than 2.0% of total revenue for the three and six months ended June 30, 2026 and 2025. Additionally, revenue generated from sales in the broader Middle East region represents less than 3.0% of total revenue for the three and six months ended June 30, 2026 and 2025.

FACTORS AFFECTING PHARMACEUTICAL PRICING AND OTHER DEVELOPMENTS

InDrug ~~August~~prices ~~2022~~are ~~the~~under ~~IRA~~significant ~~was~~scrutiny ~~signed~~in ~~into~~the ~~law~~markets in ~~the~~which ~~U.S.~~our ~~The~~products ~~IRA~~are ~~introduced~~prescribed; ~~new~~for ~~tax~~example ~~provisions,~~the ~~including~~IRA ahas ~~15.0%~~certain ~~corporate~~provisions ~~alternative~~related ~~minimum~~to ~~tax~~drug ~~and~~pricing, aincluding ~~1.0%~~the ~~excise~~ability ~~tax~~for onthe ~~stock repurchases~~U.S. ~~The~~government ~~provisions~~to ofset ~~the~~prices ~~IRA~~for ~~are~~certain ~~effective~~drugs ~~for~~in ~~periods~~Medicare. ~~after~~We ~~December~~expect ~~31,~~drug ~~2022.~~pricing ~~The~~and ~~IRA~~other ~~did~~healthcare ~~not~~costs ~~result~~will incontinue ~~any~~to ~~material~~be ~~adjustments~~subject to ~~our~~political ~~income~~and ~~tax~~societal ~~provision~~pressures oron ~~other~~a ~~income~~global ~~tax~~basis. ~~balances~~As asthe ofpolicy ~~March~~environment 31remains dynamic, ~~2026~~we ~~and~~will ~~December~~continue ~~31,~~to ~~2025.~~monitor ~~Preliminary~~how ~~guidance~~uncertainty ~~has~~with ~~been~~respect ~~issued~~to byhow the ~~IRS~~U.S. and weforeign ~~expect~~tariffs ~~additional guidance~~ and ~~regulations~~the ~~to be issued in future periods~~U.S. Weand ~~continue~~international topricing ~~assess~~may ~~its potential~~ impact on our business ~~and~~in ~~results~~the ~~of operations as further information becomes available~~future.

Additionally, our ability to set the price for our products varies significantly from country to country and, as a result, so can the price or reimbursement of our products. Governments may use a variety of cost-containment measures to control the cost of medicines, including price cuts, mandatory rebates, value-based pricing and reference pricing (i.e., referencing prices in other countries and using those reference prices to set a price).

In August 2022 the IRA was signed into law in the U.S. The IRA introduced new tax provisions, including a 15.0% corporate alternative minimum tax and a 1.0% excise tax on stock repurchases. The provisions of the IRA are effective for periods after December 31, 2022. The IRA did not result in any material adjustments to our income tax provision or other income tax balances as of June 30, 2026 and December 31, 2025. Preliminary guidance has been issued by the IRS and we expect additional guidance and regulations to be issued in future periods. We continue to assess its potential impact on our business and results of operations as further information becomes available.

The IRA also contains substantial drug pricing reforms that may have a significant impact on the pharmaceutical industry in the U.S. This includes the following:

(i) allowing CMS to negotiate prices for select high-cost Medicare Part D drugs (beginning in 2026) and Part B drugs (beginning in 2028) to reduce out-of-pocket prescription drug costs for beneficiaries, potentially resulting in higher contributions from plans and manufacturers;

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(ii) drug inflationary rebate requirements to penalize manufacturers from raising the prices of Medicare covered single-source drugs and biologics beyond the inflation-adjusted rate, beginning in 2022 for Part D drugs and 2023 for Part B drugs;

(iii) to incentivize biosimilar development, the IRA provides an 8.0% Medicare Part B add-on payment for qualifying biosimilar products for a five-year period; and

(iv) Medicare Part D redesign which replaces the current coverage gap provisions and establishes a $2,000 cap for out-of-pocket costs for Medicare beneficiaries beginning in 2025, with manufacturers being responsible for up to 10.0% of costs up to the $2,000 cap and up to 20.0% after that cap is reached.

The IRA's drug pricing controls and Medicare Part D redesign had an adverse impact on our sales, particularly for our products that are more substantially reliant on Medicare reimbursement. The IRA Medicare Part D redesign had a modest net unfavorable impact to our full-year 2025 revenue of approximately $90.0 million, concentrated in our SKYCLARYS and MS portfolio product revenue, approximately a quarter of which was associated with SKYCLARYS.

46The degree of impact from this legislation on our business depends on a number of forthcoming implementation actions by regulatory authorities, which may be further impacted by other legislative acts that may modify or replace the IRA, such as the OBBBA, as discussed below. The full extent of the IRA's impact on our sales and, in turn, our business, remains uncertain.

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The degree of impact from this legislation on our business depends on a number of forthcoming implementation actions by regulatory authorities, which may be further impacted by other legislative acts that may modify or replace the IRA, such as the OBBBA, as discussed below. The full extent of the IRA's impacts on our sales and, in turn, our business, remains uncertain.

Additionally, in May 2025 the U.S. government issued an executive order aiming to establish an MFN drug pricing policy that would tie U.S. drug prices to the prices paid for drugs in other developed countries. If HHS sets MFN pricing targets for prescription drugs, including the use of international reference pricing to set drug prices in the U.S., it could result in reduced prices and reimbursement for certain of our products in the U.S. We continue to evaluate the potential impact of this executive order. This executive order and any additional legislation, regulations or initiatives related to drug pricing, such as the CMS-proposed MFN initiatives, the Global Benchmark for Efficient Drug Pricing for certain Medicare Part B drugs and the Guarding U.S. Medicare Against Rising Drug Costs for certain Medicare Part D drugs, could create additional uncertainty around the timing and prioritization around worldwide commercial efforts and adversely impact our business and results of operations.

2025 LEGISLATION AND TAX REFORM

On July 4, 2025, the U.S. signed into law the H.R.1 legislation formally titled "An Act to Provide for Reconciliation Pursuant to Title II of H. Con. Res. 14", commonly referred to as the OBBBA.

The OBBBA contains tax provisions, such as the permanent extension or revision of certain expiring provisions of the Tax Cuts and Jobs Act enacted in 2017, modifications to the international tax framework and the restoration of favorable tax treatment for certain business provisions. The provisions of the OBBBA have multiple effective dates, with certain provisions effective in 2025 and others implemented through 2027.

Given the complexity of tax laws, related regulations and interpretations, our current estimates may require revision as additional information becomes available regarding the application of the OBBBA provisions.

The OBBBA also enacts significant potential changes to Medicaid funding and rescinds or does not continue elements of the PPACA. The OBBBA implements additional eligibility rules on government health plans, expands administrative procedures around enrollment, modifies how states can obtain federal funding for Medicaid and no longer extends ACA premium subsidies. Additional federal and state guidance is expected to be issued in order to implement these OBBBA provisions, most of which have effective dates in 2027 and 2028.

At this time, we are unable to determine the overall impact that the OBBBA will have on our business, results of operations and financial condition, or the impact the OBBBA will have on the pharmaceutical industry as a whole because any such impact will depend upon developing interpretations of the OBBBA provisions and implementing regulations, which may be material.

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FINANCIAL HIGHLIGHTS

As described below under Results of Operations, our net income and diluted earnings per share attributable to Biogen Inc. for the three months ended ~~March~~June 3130, 2026, compared to the three months ended ~~March~~June 3130, 2025, reflects the following:


TOTAL REVENUE

Increased

$4690.85 million or 13.94%


DILUTED EARNINGS PER SHARE

~~Increased~~Decreased

$03.5167 or 3184.18%


PRODUCT REVENUE, NET

Increased

$2537.87 million or 12.50%

•MSRare disease revenue increased $458.57 million, or 010.58%

•~~Rare~~Specialized ~~disease~~immunology revenue ~~decreased~~of $6127.18 million~~, or 1.1%~~

•~~The increase in~~ MS ~~product~~ revenue ~~was~~decreased ~~primarily~~$143.9 ~~due to an increase in global TYSABRI and VUMERITY revenue driven by favorable pricing and channel dynamics as well as the favorable impact of foreign currency exchange~~million, ~~partially~~or ~~offset by a decrease in global demand of TECFIDERA, particularly in Europe, driven by generic competition~~13.0%

•The ~~decrease~~increase in rare disease product revenue was primarily due to ~~unfavorable~~revenue ~~inventory~~growth ~~dynamics~~from ~~resulting~~our ~~from~~launch products, including SKYCLARYS and QALSODY as well as the ~~timing~~launch of ~~shipments~~the ~~for~~high ~~SPINRAZA~~dose inregimen ~~certain~~of ~~international markets~~SPINRAZA, partially offset by ~~revenue~~unfavorable ~~growth~~inventory dynamics resulting from ~~our~~timing ~~new~~of ~~product~~shipments ~~launches,~~of ~~including~~SPINRAZA ~~SKYCLARYS~~in ~~and~~certain ~~QALSODY~~international markets.

•~~ZURZUVAE~~U.S. revenue offor SYFOVRE and EMPAVELI was $55127.48 million, inwhich ~~the~~we ~~first~~began ~~quarter~~recognizing ofduring ~~2026~~the ~~was~~quarter, ~~driven~~subsequent byto ~~the~~our ~~continued~~acquisition ~~launch~~of inApellis ~~the~~on UMay 14, 2026.S.

•The decrease in MS product revenue was primarily due to a decrease in global demand of TECFIDERA, particularly in Europe, resulting from generic competition as well as decrease in global demand of our Interferon products as patients continue the long-term trend of transitioning to oral and higher efficacy therapies.

•ZURZUVAE revenue of $70.8 million in the second quarter of 2026 was driven by the continued launch in the U.S.


TOTAL COST AND EXPENSE

~~Decreased~~Increased

$19702.71 million or 036.9%

•Cost of sales increased $31171.79 million, or 528.04%

•R&D expense increased $~~104~~130.96 million, or 2432.27%

•SG&A expense increased $34125.89 million, or 621.16%

•Acquired IPR&D, upfront and milestone expense ~~decreased~~increased $~~166~~117.74 million, or 83251.19%

•The increase in cost of sales was primarily due to higher ~~period~~amortization costs associated with the acquired inventory fair value step-up adjustment, which increased by $112.8 million, as well as higher revenues.

•The increase in R&D expense was primarily due to approximately $5637.85 million of step-up amortization related to SKYCLARYS inventory, ~~and~~ higher spend on clinical trials, including felzartamab, salanersen and litifilimab as well as operating expense from Apellis.

•The increase in SG&A expense was primarily due to the inclusion of the commercial and management operations of Apellis subsequent to our acquisition of the company and an increase in operational spending on sales and marketing activities in support of our U.S. and international product launches.

•The ~~decrease~~increase in acquired IPR&D, upfront and milestone expense was due to ~~higher~~$164.0 million in upfront and milestone payments in the ~~first~~second quarter of ~~2025 of $200.7 million~~2026, ~~compared~~primarily todriven ~~$34.0~~by ~~million~~our inagreement ~~the~~with ~~first~~TJ ~~quarter of 2026~~Bio.


FINANCIAL CONDITION, LIQUIDITY AND CAPITAL RESOURCES

•Cash, cash equivalents and marketable securities totaled approximately $41.73 billion as of ~~March~~June 3130, 2026, compared to approximately $4.2 billion as of December 31, 2025. The decrease was primarily due to total consideration paid of $5.1 billion for our acquisition of Apellis, net of cash acquired, partially offset by net borrowings of $1.8 billion.

•We generated approximately $~~645~~1.51 ~~million~~billion of net cash flow from operations for the ~~three~~six months ended ~~March~~June 3130, 2026, compared to approximately $~~259~~420.32 million in the prior year comparative period. The increase was primarily due to higher worldwide tax payments in 2025.

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RECENT DEVELOPMENTS

ACQUISITIONS

APELLIS PHARMACEUTICALS, INC.

InOn ~~March~~May 14, 2026, we ~~entered~~completed ~~into~~the anacquisition ~~agreement~~of ~~to acquire~~ all of the issued and outstanding shares of Apellis ~~Pharmaceuticals~~, ~~Inc.,~~ a commercial-stage biopharmaceutical company focused on the discovery, development and commercialization of novel therapeutic compounds to treat diseases with high unmet needs. As a result of this ~~proposed~~ acquisition we ~~would~~acquired ~~acquire~~ two FDA-approved products from Apellis: SYFOVRE (pegcetacoplan injection) for the treatment of GA, an immune-mediated retinal disease; and EMPAVELI (pegcetacoplan) for the treatment of PNH, a rare blood disorder, and C3G and primary IC-MPGN, in rare immune-mediated kidney diseases. The addition of Apellis is expected to enhance our short- and long-term revenue growth profile by adding two commercialized, differentiated, specialized immunology ~~and~~products ~~rare disease medicines~~ to our growth portfolio.

Under the terms of ~~the~~this ~~proposed~~ acquisition, weApellis ~~would~~shareholders ~~pay~~were ~~Apellis~~entitled ~~shareholders~~to $41.00 ~~per~~ ~~share~~ in cash, ~~representing~~for aneach ~~expected~~issued ~~total~~and ~~transaction~~outstanding ~~value~~Apellis ofshare, which totaled approximately $5.63 billion, and one contractual, non-transferable contingent value right per share representing the right to receive contingent cash payments of up to an aggregate of $4.00 per share in cash, subject to the achievement of specified annual global net sales thresholds for SYFOVRE. In addition, the total purchase price included approximately $70.7 million of future consideration attributable to pre-acquisition services.

We ~~plan~~funded tothis ~~fund the proposed~~ acquisition of Apellis ~~through~~with ~~approximately $3.6 billion of~~ available cash and marketable securities on hand, supplemented by ~~approximately~~the issuance of a $2.0 billion interm ~~bank~~loan ~~loans.~~under Weour ~~expect~~2026 ~~this~~Term ~~transaction~~Loan toand bea ~~accounted~~$400.0 million ~~for~~drawdown asfrom aour ~~business~~revolving ~~combination~~credit facility.

~~COLLABORATIVE~~We ~~AND~~accounted ~~OTHER~~for ~~RELATIONSHIPS~~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.

TJFor ~~BIOPHARMA~~additional ~~CO.~~information on our acquisition of Apellis, ~~LTD~~please read Note 2, Acquisitions, to our condensed consolidated financial statements included in this report.

InRAYTHERA ~~April 2026 we entered into a definitive agreement with TJ Biopharma Co~~INC.~~, Ltd. to acquire TJ Bio's exclusive rights to felzartamab in the greater China region. With this agreement, we will own exclusive worldwide rights to felzartamab.~~

~~Under~~In ~~the~~June ~~terms~~2026 ofwe ~~this~~entered into a definitive agreement weto ~~made~~acquire anall ~~upfront~~of ~~payment~~the issued and outstanding shares of ~~$100~~RayThera Inc.~~0 million~~, toa TJprivate ~~Bio,~~biotechnology ~~which~~company ~~will~~focused beon ~~recognized~~discovering inand ~~acquired~~developing ~~in-process~~small ~~research~~molecule ~~and~~therapies ~~development,~~in ~~upfront~~immunology. ~~and~~RayThera's ~~milestone~~portfolio ~~expense~~includes ~~within~~a ~~our~~lead ~~condensed~~program ~~consolidated~~which ~~statements~~entered ofPhase ~~income~~1 development during the ~~second~~third quarter of 2026 and other anti-inflammatory assets that could potentially treat immune-mediated conditions across a range of indications.

The proposed acquisition excludes certain preclinical assets, which will be divested from RayThera into a newly formed independent company prior to the expected closing of this acquisition.

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

TJ BIOPHARMA (HANGZHOU) CO., LTD.

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COLLABORATIVE AND OTHER RELATIONSHIPS

ALTEOGEN INC.

In March 2026 we entered into an exclusive license agreement with Alteogen Inc. to enable the development of a subcutaneous formulation of ~~felzartamab~~two biologics using Alteogen's ALT-B4 hyaluronidase technology.

In connection with the closing of this transaction we accrued an upfront payment of $20.0 million to Alteogen, which was recognized in acquired in-process research and development, upfront and milestone expense within our condensed consolidated statements of income for the ~~three~~six months ended ~~March~~June 3130, 2026, ~~which~~and was ~~subsequently~~ paid induring ~~April~~the second quarter of 2026.

Alteogen will also be eligible to receive a $10.0 million option payment if a second program is selected for development, ~~and~~as well as potential development, regulatory and commercial milestone payments ~~of up to $39.0 million, $80.0 million~~ and ~~$430.0~~tiered ~~million~~royalties ~~respectively, if all specified milestones set forth~~ in ~~this~~the ~~collaboration~~mid-single ~~for~~digit ~~both~~percentages ~~programs are achieved. In addition, we may pay Alteogen tiered royalties~~ on ~~potential~~ net sales of any combination products ~~under~~resulting ~~this~~from ~~collaboration in~~ the ~~mid-single digit percentages~~collaboration.

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ALLOY THERAPEUTICS, INC.

In March 2026 we entered into a collaboration and license agreement with Alloy Therapeutics Inc. for the use of Alloy’s novel and proprietary AntiClastic ASO Platform. Through this collaboration, we ~~will~~plan to apply the platform to advance antisense therapeutics against multiple targets.

In connection with the closing of this transaction we accrued an upfront payment of $12.0 million to Alloy, which was recognized in acquired in-process research and development, upfront and milestone expense within our condensed consolidated statements of income for the ~~three~~six months ended ~~March~~June 3130, 2026., Weand ~~expect~~was ~~this upfront milestone to be~~ paid during the second quarter of 2026.

Alloy will also be eligible to receive potential milestone payments and tiered royalties on any products resulting from the collaboration.

DEVELOPMENTS IN KEY COLLABORATIVE RELATIONSHIPS

LEQEMBI (lecanemab)

United States

Key developments related to LEQEMBI in the U.S. during 2026 consisted of the following:

•In May 2026 the FDA extended the review period by three months for the supplemental BLA for LEQEMBI subcutaneous autoinjector, LEQEMBI IQLIK, for a weekly initiation dose, with a new PDUFA action date of August 24, 2026; in July 2026 the FDA approved the supplemental BLA.

•In March 2026 we and our collaboration partner Eisai announced new real-world findings from an analysis of long-term treatment persistence and baseline characteristics among people receiving IV lecanemab. The findings showed that most patients continue with ongoing maintenance therapy after the initial 18 months of treatment.

•In January 2026 the FDA accepted for review the supplemental BLA for LEQEMBI subcutaneous autoinjector, LEQEMBI IQLIK, for a weekly starting dose, with a PDUFA action date of May 24, 2026.

Rest of World

Key developments related to LEQEMBI (lecanemab) in rest of world markets during 2026 consisted of the following:

•In February 2026 the BLA for LEQEMBI subcutaneous autoinjector was designated for Priority Review by the NMPA in China.

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OTHER KEY DEVELOPMENTS

BIIB091

•In July 2026 we announced that the Phase 2 data in relapsing-remitting multiple sclerosis has achieved proof-of-concept and that we will be exploring next steps for the asset.

ZURZUVAE (zuranalone)

•In September 2025 the EC approved ZURZUVAE in the E.U. for the treatment of PPD in adults following childbirth, offering the first and only treatment indicated for PPD in the E.U. In July 2026 ZURZUVAE launched in Germany.

DIRANERSEN (BIIB080)

•In May 2026, we announced topline results from the Phase 2 CELIA study evaluating diranersen, an investigational ASO therapy targeting tau, in individuals with early Alzheimer's disease. CELIA did not meet its primary endpoint assessing dose response; based upon what we believe to be an unprecedented combination of reduction in tau pathology and clinical benefit, including cognition, we plan to advance diranersen to registrational development.

LITIFILIMAB

•In March 2026 we announced positive results from the Phase 2 part of the AMETHYST Phase 2/3 study (Part A) of litifilimab in people living with CLE. The Phase 2 part of the AMETHYST study met its primary endpoint of reduction of disease activity in people living with CLE at Week 16, with more litifilimab participants achieving clear/almost clear skin. If approved, litifilimab could be the first targeted therapy for this disease.

•In January 2026 the FDA granted Breakthrough Therapy designation for litifilimab for the treatment of CLE.

SALANERSEN (BIIB115)

•In March 2026 we presented additional results from the Phase 1b study of salanersen, an ASO given once a year for the treatment of SMA. The data showed support for the safety and effectiveness of salanersen over one year of treatment in children with SMA who had the potential for improvement due to suboptimal clinical status with prior gene therapy.

•In June 2026 the FDA granted Breakthrough Therapy designation for salanersen for the treatment of SMA.

SPINRAZA (nusinersen)

•In March 2026 the FDA approved the high dose regimen of SPINRAZA, which is comprised of 50 mg/5 mL and 28mg/5 mL doses for the treatment of SMA.

•In January 2026 the EC granted marketing authorization for a high dose regimen of SPINRAZA in the E.U. for the treatment of 5q SMA, which is the most common form of the disease and represents approximately 95% of all SMA cases. The high dose regimen is comprised of 50 mg/5 mL and 28 mg/5 mL doses and individuals transitioning from the 12 mg dose will receive one 50 mg dose in place of their next 12 mg dose, followed by 28 mg maintenance doses every four months thereafter.

50DISCONTINUED PROGRAMS AND STUDIES

BIIB122

•In May 2026 we and our collaboration partner Denali, announced topline results from the Phase 2b LUMA study evaluating BIIB122, an investigational small molecule inhibitor of LRRK2 in individuals with early-stage Parkinson's disease. Results from the study show that BIIB122 did not meet its primary and secondary endpoints. Based on these results we and Denali will discontinue development of BIIB122 in idiopathic Parkinson's disease.

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RESULTS OF OPERATIONS

REVENUE

The following revenue discussion should be read in conjunction with Note 5, Revenue, to our condensed consolidated financial statements included in this report.

Revenue is summarized as follows:

	For the Three Months Ended March 31,
	For the Three Months Ended June 30,
(In millions, except percentages)	2026				2025				$ Change		% Change
Product revenue, net:
United States	$	~~839~~1,114.25	3340.97	%	$	~~753~~941.81	3135.06	%	$	85173.4	1118.34	%
Rest of world	~~913~~801.19		3629.83		~~972~~937.76		4035.04		(59135.67)		(614.15)
Total product revenue, net	1,~~752~~916.34		70.70		1,~~726~~878.57		71.0		2537.87		12.50
Revenue from anti-CD20 therapeutic programs	~~419~~513.15		1618.98		~~378~~467.23		1517.57		4046.92		109.89
Alzheimer's collaboration revenue(1)	5963.57		2.43		3354.09		12.41		268.58		8016.30
Contract manufacturing, royalty and other revenue	~~246~~242.94		108.09		~~293~~244.36		129.12		(462.42)		(150.89)
Total revenue	$	2,~~477~~736.80	100.0	%	$	2,~~431~~645.05	100.0	%	$	4690.85	13.94	%
	For the Six Months Ended June 30,
(In millions, except percentages)	2026				2025				$ Change		% Change
Product revenue, net:
United States	$	1,953.7	37.5	%	$	1,694.9	33.4	%	$	258.8	15.3	%
Rest of world	1,715.0		32.9		1,910.3		37.6		(195.3)		(10.2)
Total product revenue, net	3,668.7		70.4		3,605.2		71.0		63.5		1.8
Revenue from anti-CD20 therapeutic programs	932.6		17.9		845.5		16.7		87.1		10.3
Alzheimer's collaboration revenue(1)	123.2		2.3		87.9		1.7		35.3		40.2
Contract manufacturing, royalty and other revenue	489.3		9.4		537.9		10.6		(48.6)		(9.0)
Total revenue	$	5,213.8	100.0	%	$	5,076.5	100.0	%	$	137.3	2.7	%

(1) Alzheimer's collaboration revenue consists of our 50.0% share of LEQEMBI product revenue, net and cost of sales, including royalties.

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PRODUCT REVENUE

Product revenue is summarized as follows:

	For the Three Months Ended March 31,
	For the Three Months Ended June 30,
	2026								2025
(In millions, except percentages)	UnitedStates		Rest ofWorld		Total		%Total		UnitedStates		Rest ofWorld		Total		%Total		$Change		% Change
Multiple Sclerosis	$	~~559~~621.40	$	~~398~~342.13	$	~~957~~963.53	5450.62	%	$	~~490~~657.4	$	~~462~~449.68	$	~~953~~1,107.02	5558.29	%	$	4(143.59)	0(13.50)	%
Rare Disease	~~224~~294.59		~~332~~306.78		~~557~~601.27		31.84		~~231~~234.08		~~332~~308.32		~~563~~543.30		3228.69		(658.1)7		(110.1)8
Biosimilars	—		182.2		182.2		10.4		4.3		176.5		180.8		10.5		1.4		0.8
Specialized Immunology(1)	127.8		—		127.8		6.7		—		—		—		—		127.8		—
Other(1)	55.3		0.1		55.4		3.2		28.1		1.3		29.4		1.7		26.0		88.4
Biosimilars	0.1		152.7		152.8		8.0		2.5		179.2		181.7		9.7		(28.9)		(15.9)
Total product revenue, net	$	839.2	$	913.1	$	1,752.3	100.0	%	$	753.8	$	972.7	$	1,726.5	100.0	%	$	25.8	1.5	%
Other(2)	70.7		0.1		70.8		3.7		46.4		0.4		46.8		2.5		24.0		51.3
Total product revenue, net	$	1,114.5	$	801.9	$	1,916.4	100.0	%	$	941.1	$	937.6	$	1,878.7	100.0	%	$	37.7	2.0	%
	For the Six Months Ended June 30,
	2026								2025
(In millions, except percentages)	UnitedStates		Rest ofWorld		Total		%Total		UnitedStates		Rest ofWorld		Total		%Total		$Change		% Change
Multiple Sclerosis	$	1,180.4	$	740.4	$	1,920.8	52.4	%	$	1,147.8	$	912.4	$	2,060.2	57.1	%	$	(139.4)	(6.8)	%
Rare Disease	519.4		639.5		1,158.9		31.6		465.8		640.5		1,106.3		30.7		52.6		4.8
Specialized Immunology(1)	127.8		—		127.8		3.5		—		—		—		—		127.8		—
Biosimilars	0.1		334.9		335.0		9.1		6.8		355.7		362.5		10.1		(27.5)		(7.6)
Other(2)	126.0		0.2		126.2		3.4		74.5		1.7		76.2		2.1		50.0		65.6
Total product revenue, net	$	1,953.7	$	1,715.0	$	3,668.7	100.0	%	$	1,694.9	$	1,910.3	$	3,605.2	100.0	%	$	63.5	1.8	%

(1) ~~Other~~Specialized Immunology includes ~~ZURZUVAE~~EMPAVELI and SYFOVRE, ~~FUMADERM~~which ~~and~~were ~~ADUHELM~~obtained as part of our acquisition of Apellis in May 2026.

51(2) Other includes ZURZUVAE, FUMADERM and ADUHELM.

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MULTIPLE SCLEROSIS

•Global TYSABRI revenue ~~increased~~decreased $603.08 million, from $~~381~~454.56 million in 2025 to $~~441~~450.58 million in 2026, or 150.78%, primarily due to ~~favorable channel dynamics,~~ a ~~favorable~~decrease ~~pricing change~~ in ~~estimates in the~~ U.S., ~~an increase in rest of world~~ demand ~~driven~~resulting byfrom ~~the~~increased ~~subcutaneous~~competition ~~offering~~ and ~~the~~timing ~~favorable~~of ~~impact~~shipments ofin ~~foreign~~certain ~~currency~~international ~~exchange~~markets. The ~~increase~~decrease was partially offset by a ~~decrease~~favorable pricing change in the U.S. ~~demand~~and ~~driven~~the byfavorable ~~increased~~impact ~~competition~~of foreign currency exchange.

•Global VUMERITY revenue ~~increased~~decreased $4015.28 million, from $~~138~~212.83 million in 2025 to $~~179~~196.05 million in 2026, or 297.04%, primarily due to ~~favorable~~inventory ~~pricing and channel~~ dynamics ~~in the U~~.~~S., an increase in rest of world demand and the favorable impact of foreign currency exchange.~~

•Global TECFIDERA revenue decreased $96102.67 million, from $~~206~~193.16 million in 2025 to $~~109~~90.59 million in 2026, or 4653.90%, driven by a decrease in global demand, particularly in Europe, as a result of multiple TECFIDERA generic entrants.

•Global Interferon revenue ~~increased~~decreased $121.26 million, from $~~226~~246.37 million in 2025 to $~~227~~225.51 million in 2026, or 08.58%, driven by ana ~~increase~~decrease in ~~pricing~~global indemand ~~the~~as ~~U.S.~~patients ~~and~~continue the ~~favorable~~long-term ~~impact~~trend of ~~foreign~~transitioning ~~currency~~to ~~exchange,~~oral ~~offset~~and byhigher aefficacy ~~decrease~~therapies, inpartially ~~demand~~offset asby ~~patients~~an ~~transition~~increase toin ~~higher~~pricing ~~efficacy~~in ~~therapies~~the U.S.

In•Global ~~2026~~TYSABRI ~~we expect total MS~~ revenue ~~will~~increased ~~decline~~$56.2 asmillion, afrom ~~result~~$836.1 ofmillion ~~increasing competition for many of our MS products~~ in ~~both~~2025 ~~the~~to U$892.S.3 ~~and~~million ~~rest of world markets. We expect TECFIDERA revenue will be adversely impacted by accelerating generic competition~~ in ~~certain~~2026, ~~markets~~or ~~in the E~~6.~~U. Additionally~~7%, aprimarily ~~biosimilar~~due ~~entrant~~to ofa ~~TYSABRI~~favorable ~~was~~pricing ~~approved~~change in the U.S. and the ~~E.U.~~favorable inimpact ~~2023. We expect the future sales~~ of ~~TYSABRI~~foreign ~~will~~currency ~~continue to be adversely affected by the entrance of this biosimilar~~exchange. ~~We expect the decline to be partially offset by continued increasing demand for VUMERITY.~~

52•Global VUMERITY revenue increased $24.4 million, from $351.1 million in 2025 to $375.5 million in 2026, or 6.9%, primarily due to favorable pricing in the U.S., partially offset by inventory dynamics.

•Global TECFIDERA revenue decreased $199.3 million, from $399.7 million in 2025 to $200.4 million in 2026, or 49.9%, driven by a decrease in global demand, particularly in Europe, as a result of multiple TECFIDERA generic entrants.

•Global Interferon revenue decreased $20.4 million, from $473.0 million in 2025 to $452.6 million in 2026, or 4.3%, driven by a decrease in global demand as patients continue the long-term trend of transitioning to oral and higher efficacy therapies, partially offset by an increase in pricing in the U.S. and the favorable impact of foreign currency exchange.

MS revenue includes sales from TECFIDERA, VUMERITY, AVONEX, PLEGRIDY and TYSABRI.

In 2026 we expect total MS revenue will decline as a result of high levels of competition for many of our MS products in both the U.S. and rest of world markets. We expect TECFIDERA revenue will be adversely impacted by accelerating generic competition in certain markets in the E.U., and we expect TYSABRI revenue to continue to be adversely affected by the entrance of a biosimilar.

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RARE DISEASE

•U.S. SPINRAZA revenue ~~decreased~~increased $1255.20 million, from $~~154~~149.43 million in 2025 to $~~142~~204.23 million in 2026, or 736.98%, primarily ~~due~~driven toby ~~lower~~ demand and ~~unfavorable~~stocking ~~inventory~~for ~~dynamics~~the high-dose regimen.

•Rest of world SPINRAZA revenue decreased $3745.78 million, from $~~269~~243.54 million in 2025 to $~~231~~197.86 million in 2026, or 1418.08%, primarily due to unfavorable inventory dynamics ~~driven~~resulting byfrom ~~the~~ timing of shipments of SPINRAZA in certain international markets, ~~compared~~partially tooffset ~~the~~by ~~first~~higher ~~quarter~~pricing of ~~2025. The decrease was also driven by a one-time VAT refund received during~~ the ~~first~~high ~~quarter~~dose ofregimen ~~2025~~and ~~of approximately $18.1 million, partially offset by~~ the favorable impact of foreign currency exchange.

•Global SKYCLARYS revenue increased $2637.86 million, from $~~123~~130.93 million in 2025 to $~~150~~167.79 million in 2026, or 2128.69%, primarily related to an increase in ~~rest~~global ofdemand ~~world~~mostly ~~sales volumes~~ driven by the continued launch in Europe and certain other international markets~~, partially offset by unfavorable inventory dynamics in the U~~.S.

•Global QALSODY revenue increased $1711.09 million, from $1520.50 million in 2025 to $3231.59 million in 2026, or ~~109~~59.75%, primarily related to an increase in rest of world sales volumes driven by the continued launch in international markets.

•U.S. SPINRAZA revenue increased $42.8 million, from $303.7 million in 2025 to $346.5 million in 2026, or 14.1% primarily driven by demand and stocking for the high-dose regimen.

•Rest of world SPINRAZA revenue decreased $83.5 million, from $512.9 million in 2025 to $429.4 million in 2026, or 16.3%, primarily due to unfavorable inventory dynamics resulting from timing of shipments of SPINRAZA in certain international markets, partially offset by the favorable impact of foreign currency exchange.

•Global SKYCLARYS revenue increased $64.4 million, from $254.2 million in 2025 to $318.6 million in 2026, or 25.3%, primarily related to an increase in global demand mostly driven by the continued launch in Europe and certain other international markets.

•Global QALSODY revenue increased $28.9 million, from $35.5 million in 2025 to $64.4 million in 2026, or 81.4%, primarily related to an increase in rest of world sales volumes driven by the continued launch in Europe.

Rare disease revenue includes sales from SPINRAZA, QALSODY and SKYCLARYS.

In 2026 we expect growth in rare disease revenue due to the continued launch of SKYCLARYS in Europe and other international markets as well as the continued launch of QALSODY in Europe. We anticipate global SPINRAZA revenue growth to be relatively flat in 2026.

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SPECIALIZED IMMUNOLOGY

•In connection with our acquisition of Apellis on May 14, 2026, we acquired SYFOVRE (pegcetacoplan injection) for the treatment of GA, an immune-mediated retinal disease and EMPAVELI (pegcetacoplan) for the treatment of PNH, a rare blood disorder, and C3G and IC-MPGN, rare immune-mediated kidney diseases. U.S. revenue for SYFOVRE and EMPAVELI were $97.4 million and $30.4 million, respectively for the three and six months ended June 30, 2026.

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

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BIOSIMILARS

•For the three and six months ended ~~March~~June 3130, 2026, compared to the same ~~period~~periods ofin 2025, the ~~increase~~decreases in biosimilar revenue ~~was~~were primarily due to ~~the~~a ~~favorable~~decrease ~~impact~~in ofsales ~~foreign~~volume ~~currency~~and ~~exchange~~unfavorable pricing resulting from competition, partially offset by athe ~~decrease~~favorable inimpact ~~sales~~of ~~volumes~~foreign currency exchange.

Biosimilars revenue includes sales from BENEPALI, IMRALDI, FLIXABI, BYOOVIZ and TOFIDENCE. In 2025 we completed the sale of our rights to TOFIDENCE and BYOOVIZ.


OTHER PRODUCT REVENUE

ZURZUVAE

~~Global~~For three months ended June 30, 2026, global ZURZUVAE revenue increased $2724.74 million, from $2746.74 million in 2025 to $5570.48 million in 2026, or ~~100~~52.06%. For six months ended June 30, 2026, global ZURZUVAE revenue increased $52.1 million, from $74.1 million in 2025 to $126.2 million in 2026 or 70.3%. The increases were primarily due to higher demand resulting from an increase in total patients in the U.S. We anticipate growth in U.S. ZURZUVAE revenue as we expect total patients to continue to increase in 2026.

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REVENUE FROM ANTI-CD20 THERAPEUTIC PROGRAMS

Our share of RITUXAN, including RITUXAN HYCELA, GAZYVA and LUNSUMIO collaboration operating profits in the U.S., royalty revenue on sales of OCREVUS and other revenue from anti-CD20 therapeutic programs are summarized in the table below. For purposes of this discussion, we refer to RITUXAN and RITUXAN HYCELA collectively as RITUXAN.

	For the Three Months Ended March 31,
	For the Three Months Ended June 30,				For the Six Months Ended June 30,
(In millions)	2026		2025		2026	2025
Royalty revenue on sales of OCREVUS	$	~~317~~381.24	$	~~288~~353.8

Filing Compare · BIOGEN INC.