Aktieanalys – källarkiv Uppdaterad 2026-08-06T05:05:22Z

SEC EDGAR · 10-Q

10-Q – 2026-07-29 – biib-20260630.htm

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Omsättning
  • Item 2. Unregistered Sales of Equity Securities and Use of Proceeds | 100
  • 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 thi | • 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 impair
  • • 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 impair | • 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 reimb
  • • 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 impair | • 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 reimb | • 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 TECFIDER
  • • 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;
  • • 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;
  • • 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;
  • 2026 2025 2026 2025 | Revenue: | Product revenue, net $ 1,916.4 $ 1,878.7 $ 3,668.7 $ 3,605.2
Rörelseresultat
  • Net Gains/(Losses) | Reclassified from AOCI into Operating Income (in millions) Net Gains/(Losses) Excluded from Effectiveness Testing and | Recognized in Operating Income (in millions)
  • Reclassified from AOCI into Operating Income (in millions) Net Gains/(Losses) Excluded from Effectiveness Testing and | Recognized in Operating Income (in millions) | Location 2026 2025 Location 2026 2025
Periodens resultat
  • Net income attributable to Biogen Inc. $ 97.5 $ 634.8 $ 417.0 $ 875.3
  • Net income per share: | Basic earnings per share attributable to Biogen Inc. $ 0.66 $ 4.33 $ 2.83 $ 5.98
  • 2026 2025 2026 2025 | Net income attributable to Biogen Inc. $ 97.5 $ 634.8 $ 417.0 $ 875.3 | Other comprehensive income (loss):
  • Cash flow from operating activities: | Net income $ 417.0 $ 875.3 | Adjustments to reconcile net income to net cash flow from operating activities:
  • Net income $ 417.0 $ 875.3 | Adjustments to reconcile net income to net cash flow from operating activities: | Depreciation and amortization 440.5 377.5
  • 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
  • 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
  • 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 )
Resultat per aktie
  • Net income per share: | Basic earnings per share attributable to Biogen Inc. $ 0.66 $ 4.33 $ 2.83 $ 5.98 | Diluted earnings per share attributable to Biogen Inc. $ 0.66 $ 4.33 $ 2.81 $ 5.97
  • Basic earnings per share attributable to Biogen Inc. $ 0.66 $ 4.33 $ 2.83 $ 5.98 | Diluted earnings per share attributable to Biogen Inc. $ 0.66 $ 4.33 $ 2.81 $ 5.97
  • Weighted-average shares used in calculating: | Basic earnings per share attributable to Biogen Inc. 147.7 146.5 147.4 146.3 | Diluted earnings per share attributable to Biogen Inc. 148.7 146.7 148.6 146.7
  • Basic earnings per share attributable to Biogen Inc. 147.7 146.5 147.4 146.3 | Diluted earnings per share attributable to Biogen Inc. 148.7 146.7 148.6 146.7
  • Note 14: | Earnings per Share
  • Basic and diluted shares outstanding used in our earnings per share calculation are calculated as follows:
  • Dilutive potential common shares 1.0 0.2 1.2 0.4 | Shares used in calculating diluted earnings per share 148.7 146.7 148.6 146.7
  • As described below under Results of Operations , our net income and diluted earnings per share attributable to Biogen Inc. for the three months ended June 30, 2026, compared to the three months ended June 30, 2025, reflects the following:
Kassaflöde
  • Condensed Consolidated Statements of Cash Flow — For the Six Months Ended June 30, 2026 and 2025 | 11
  • 1.6 — ( 0.2 ) — | Unrealized gains (losses) on cash flow hedges, net of tax | 14.8 ( 105.8 ) 67.4 ( 163.6 )
  • BIOGEN INC. AND SUBSIDIARIES | CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOW | (unaudited, in millions)
  • 2026 2025 | Cash flow from operating activities: | Net income $ 417.0 $ 875.3
  • Net income $ 417.0 $ 875.3 | Adjustments to reconcile net income to net cash flow from operating activities: | Depreciation and amortization 440.5 377.5
  • Other changes in operating assets and liabilities, net ( 143.0 ) ( 75.5 ) | Net cash flow provided by (used in) operating activities 1,094.4 420.2 | Cash flow from investing activities:
  • Net cash flow provided by (used in) operating activities 1,094.4 420.2 | Cash flow from investing activities: | Purchases of property, plant and equipment ( 92.1 ) ( 63.7 )
  • Other ( 0.8 ) ( 30.6 ) | Net cash flow provided by (used in) investing activities ( 4,048.7 ) ( 104.3 ) | Cash flow from financing activities:
Likvida medel
  • Current assets: | Cash and cash equivalents $ 1,285.0 $ 3,008.5 | Current portion of marketable securities — 807.2
  • 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
  • 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
  • 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 $ 1,285.0 $ 2,758.8
  • Cash and cash equivalents, beginning of the period 3,008.5 2,375.0 | Cash and cash equivalents, end of the period $ 1,285.0 $ 2,758.8
  • Cash and cash equivalents $ 310.7 | Accounts receivable 384.4
  • 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:
  • Financial assets: | Cash and cash equivalents $ 1,285.0 $ 3,008.5 $ (1,723.5) (57.3) % | Marketable securities — current — 807.2 (807.2) (100.0)
Nettoskuld
  • Net income $ 417.0 $ 875.3 | Adjustments to reconcile net income to net cash flow from operating activities: | Depreciation and amortization 440.5 377.5
  • Other changes in operating assets and liabilities, net ( 143.0 ) ( 75.5 ) | Net cash flow provided by (used in) operating activities 1,094.4 420.2 | Cash flow from investing activities:
  • Other ( 0.8 ) ( 30.6 ) | Net cash flow provided by (used in) investing activities ( 4,048.7 ) ( 104.3 ) | Cash flow from financing activities:
  • Other ( 2.0 ) 0.1 | 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
  • 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 a | 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.
  • • We generated approximately $1.1 billion of net cash flow from operations for the six months ended June 30, 2026, compared to approximately $420.2 million in the prior year comparative period. The increase was primarily due to higher worldwide tax payments in 2025.
  • (In millions, except percentages) 2026 2025 % Change | Net cash flow provided by (used in) operating activities $ 1,094.4 $ 420.2 160.4 % | Net cash flow provided by (used in) investing activities (4,048.7) (104.3) nm
  • Net cash flow provided by (used in) operating activities $ 1,094.4 $ 420.2 160.4 % | Net cash flow provided by (used in) investing activities (4,048.7) (104.3) nm | Net cash flow provided by (used in) financing activities 1,252.2 (34.7) nm
Eget kapital
  • Equity: | Biogen Inc. shareholders’ equity: | Preferred stock, par value $ 0.001 per share
Antal aktier
  • 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 July 27, 2026, was 147,753,998 shares.
  • Basic and diluted shares outstanding used in our earnings per share calculation are calculated as follows:
  • Denominator: | Weighted average number of common shares outstanding 147.7 146.5 147.4 146.3 | Effect of dilutive securities:
  • (1) Dr. Singhal's Rule 10b5-1 trading arrangement provides for the sale of (i) up to 20,400 shares of our common stock and (ii) all of the shares of our common stock to be acquired under our Employee Stock Purchase Plan during the term of the 10b5-1 trading arrangement. The number of shares to be acquired under the plan is not determinable at this time as the purchase price for such shares will be determined at the end of the applicable purchase period under the plan. | 100
Antal anställda
  • • 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;
  • 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 v | 16
  • 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 $ 32 | 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.
  • 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 i | 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 impac t the availability and pricing of raw materials. For example, our primary
  • 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 fluct | 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
  • 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. | 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.
  • A breakdown or breach of our information systems could subject us to liability or interrupt our business operations. | We are increasingly dependent upon information systems and data to operate our business. Changes in how we operate have caused us to modify our business practices in ways that heighten this dependence, including changing the requirement that most of our office-based employees in the U.S. and our other key markets work from the office, with many of our employees now working in hybrid or full-remote positions. As a result, we are increasingly dependent upon our information systems to operate our b | Cybersecurity threats and incidents are increasing in their frequency, sophistication and intensity, and are becoming increasingly difficult to detect, particularly when they impact employees, vendors, customers or suppliers, and other companies in our supply chain. Cybersecurity threats and incidents are often carried out by motivated, well-resourced, skilled and persistent threat actors, including nation states, organized crime groups, “hacktivists” and may include or target employees or contr
  • We are increasingly dependent upon information systems and data to operate our business. Changes in how we operate have caused us to modify our business practices in ways that heighten this dependence, including changing the requirement that most of our office-based employees in the U.S. and our other key markets work from the office, with many of our employees now working in hybrid or full-remote positions. As a result, we are increasingly dependent upon our information systems to operate our b | Cybersecurity threats and incidents are increasing in their frequency, sophistication and intensity, and are becoming increasingly difficult to detect, particularly when they impact employees, vendors, customers or suppliers, and other companies in our supply chain. Cybersecurity threats and incidents are often carried out by motivated, well-resourced, skilled and persistent threat actors, including nation states, organized crime groups, “hacktivists” and may include or target employees or contr | 91
Bruttomarginal
  • 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 | 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.

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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 June 30, 2026
OR

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

Commission File Number 0-19311

BIOGEN INC.
(Exact name of registrant as specified in its charter)

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

225 Binney Street , Cambridge , MA 02142
( 617 )  679-2000
(Address, including zip code, and telephone number, including
area code, of registrant’s principal executive offices)
Securities registered pursuant to Section 12(b) of the Act:

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

Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days:     Yes    x     No   o
Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files):     Yes    x     No   o
Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and "emerging growth company" in Rule 12b-2 of the Exchange Act:

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

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o
Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    Yes   ☐     No   x
The number of shares of the issuer’s Common Stock, $0.0005 par value, outstanding as of July 27, 2026, was 147,753,998 shares.

Table of Contents

BIOGEN INC.
FORM 10-Q — Quarterly Report
For the Quarterly Period Ended June 30, 2026
TABLE OF CONTENTS
 

    Page
PART I — FINANCIAL INFORMATION

Item 1. Financial Statements (unaudited)

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 and Six Months Ended June 30, 2026 and 2025
9

Condensed Consolidated Balance Sheets — As of June 30, 2026 and December 31, 2025
10

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 and Six Months Ended June 30, 2026 and 2025
12

Notes to Condensed Consolidated Financial Statements
14

Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations
51

Item 3. Quantitative and Qualitative Disclosures About Market Risk
81

Item 4. Controls and Procedures
83

PART II — OTHER INFORMATION

Item 1. Legal Proceedings
84

Item 1A. Risk Factors
84

Item 2. Unregistered Sales of Equity Securities and Use of Proceeds
100

Item 5. Other Information
100

Item 6. Exhibits
101

Signatures
102

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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 and 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 Apellis, including future performance of the SKYCLARYS, EMPAVELI and SYFOVRE products, 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®, ASPAVELI®, COLUMVI®, ENBREL®, EYLEA®, FAMPYRA™, GAZYVA®, LEQEMBI®, HUMIRA®, LUCENTIS®, LUNSUMIO®, OCREVUS®, REMICADE®, 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.
5

Table of Contents

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
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

6

Table of Contents

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 June 30, For the Six Months Ended June 30,
2026 2025 2026 2025
Revenue:
Product revenue, net $ 1,916.4   $ 1,878.7   $ 3,668.7   $ 3,605.2  
Revenue from anti-CD20 therapeutic programs 513.5   467.3   932.6   845.5  
Alzheimer's collaboration revenue 63.7   54.9   123.2   87.9  
Contract manufacturing, royalty and other revenue 242.4   244.6   489.3   537.9  
Total revenue 2,736.0   2,645.5   5,213.8   5,076.5  
Cost and expense:
Cost of sales, excluding amortization and impairment of acquired intangible assets 776.9   605.0   1,437.9   1,234.3  
Research and development 529.6   399.0   1,068.6   833.1  
Acquired in-process research and development, upfront and milestone expense 164.0   46.6   198.0   247.3  
Selling, general and administrative 709.7   583.8   1,317.0   1,156.3  
Amortization and impairment of acquired intangible assets 168.2   130.9   304.7   242.7  
Collaboration profit sharing/(loss reimbursement) 68.8   75.0   143.0   133.1  
(Gain) loss on fair value remeasurement of contingent consideration 2.5   13.2   23.0   22.8  

Restructuring charges 165.4   ( 0.7 ) 173.3   34.6  

Other (income) expense, net 18.5   48.7   38.2   117.1  
Total cost and expense 2,603.6   1,901.5   4,703.7   4,021.3  
Income before income tax (benefit) expense 132.4   744.0   510.1   1,055.2  
Income tax (benefit) expense 34.9   109.2   93.1   179.9  

Net income attributable to Biogen Inc. $ 97.5   $ 634.8   $ 417.0   $ 875.3  

Net income per share:
Basic earnings per share attributable to Biogen Inc. $ 0.66   $ 4.33   $ 2.83   $ 5.98  
Diluted earnings per share attributable to Biogen Inc. $ 0.66   $ 4.33   $ 2.81   $ 5.97  

Weighted-average shares used in calculating:
Basic earnings per share attributable to Biogen Inc. 147.7   146.5   147.4   146.3  
Diluted earnings per share attributable to Biogen Inc. 148.7   146.7   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 June 30, For the Six Months Ended June 30,
  2026 2025 2026 2025
Net income attributable to Biogen Inc. $ 97.5   $ 634.8   $ 417.0   $ 875.3  
Other comprehensive income (loss):
Unrealized gains (losses) on securities available for sale, net of tax
1.6   —   ( 0.2 ) —  
Unrealized gains (losses) on cash flow hedges, net of tax
14.8   ( 105.8 ) 67.4   ( 163.6 )

Unrealized gains (losses) on pension benefit obligation, net of tax
( 0.3 ) 0.6   ( 0.8 ) 1.0  
Currency translation adjustments, net of tax ( 3.6 ) 41.6   ( 12.1 ) 60.7  
Total other comprehensive income (loss), net of tax 12.5   ( 63.6 ) 54.3   ( 101.9 )
Comprehensive income (loss) attributable to Biogen Inc. $ 110.0   $ 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 June 30, 2026 As of December 31, 2025
ASSETS
Current assets:
Cash and cash equivalents $ 1,285.0   $ 3,008.5  
Current portion of marketable securities —   807.2  
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 512.8   524.6  
Inventory 2,384.3   2,168.1  
Other current assets 1,238.0   1,123.3  
Total current assets 7,305.7   8,974.1  
Marketable securities —   431.9  
Property, plant and equipment, net 2,994.1   3,055.4  
Operating lease assets 245.7   265.4  
Intangible assets, net 13,516.4   9,178.5  
Goodwill 6,990.8   6,491.1  
Deferred tax asset 202.1   292.5  
Investments and other assets 831.8   750.6  
Total assets $ 32,086.6   $ 29,439.5  
LIABILITIES AND EQUITY
Current liabilities:
Current portion of term loan $ 800.0   $ —  
Taxes payable 86.9   114.8  
Accounts payable 403.9   432.0  
Accrued expense and other 2,626.3   2,802.6  
Total current liabilities 3,917.1   3,349.4  
Notes payable and term loan 7,290.3   6,286.8  
Deferred tax liability 945.5   507.6  
Long-term operating lease liabilities 264.8   290.4  
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 983.0   863.1  
Accumulated other comprehensive income (loss) ( 127.7 ) ( 182.0 )
Retained earnings 20,969.7   20,552.7  
Treasury stock, at cost ( 2,977.1 ) ( 2,977.1 )

Total equity 18,848.0   18,256.8  
Total liabilities and equity $ 32,086.6   $ 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 Six Months Ended June 30,
  2026 2025
Cash flow from operating activities:
Net income $ 417.0   $ 875.3  
Adjustments to reconcile net income to net cash flow from operating activities:
Depreciation and amortization 440.5   377.5  
Impairment of intangible assets —   3.5  
Excess and obsolescence charges related to inventory 9.9   14.3  
Amortization of acquired inventory step-up 310.4   103.9  
Acquired in-process research and development 100.0   —  
Share-based compensation 161.4   155.9  
Contingent consideration 23.0   22.8  
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 ( 166.0 ) ( 170.5 )
Due from anti-CD20 therapeutic programs 11.8   4.2  
Inventory 191.9   ( 27.9 )
Accrued expense and other current liabilities ( 292.9 ) ( 318.7 )
Income tax assets and liabilities 32.2   ( 534.7 )
Other changes in operating assets and liabilities, net ( 143.0 ) ( 75.5 )
Net cash flow provided by (used in) operating activities 1,094.4   420.2  
Cash flow from investing activities:
Purchases of property, plant and equipment ( 92.1 ) ( 63.7 )
Proceeds from sales and maturities of marketable securities 2,140.4   —  
Purchases of marketable securities ( 896.6 ) —  
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 ( 0.8 ) ( 30.6 )
Net cash flow provided by (used in) investing activities ( 4,048.7 ) ( 104.3 )
Cash flow from financing activities:

Payments related to issuance of stock for share-based compensation arrangements, net ( 49.1 ) ( 18.2 )
Proceeds from borrowings, net 2,400.0   1,733.4  
Repayments of borrowings ( 1,096.7 ) ( 1,750.0 )

Other ( 2.0 ) 0.1  
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 $ 1,285.0   $ 2,758.8  

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 June 30, 2026
  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, 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 Additional
paid-in
capital Accumulated
other
comprehensive
income (loss) Retained
earnings Treasury stock Total
equity
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  

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 are focused on advancing our pipeline, including significant late stage programs, in neurology, specialized immunology and rare diseases across multiple modalities. Our drug discovery and development efforts 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; 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 current and other potential anti-CD20 therapies, pursuant to our collaboration arrangements with Genentech, a wholly owned member of the Roche Group. Under the collaboration arrangements, we currently recognize revenue from the following products: OCREVUS, GAZYVA, RITUXAN, RITUXAN HYCELA, LUNSUMIO and 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 June 30, 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.
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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

Apellis Pharmaceuticals, Inc.
On May 14, 2026, we completed the acquisition of all of the issued and outstanding shares of Apellis, 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 acquisition we acquired 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, 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 products to our growth portfolio.
Under 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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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

Preliminary Purchase Price Allocation
The following table summarizes the preliminary purchase price allocation of the separately identifiable assets acquired and liabilities assumed as of May 14, 2026:

(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  

Inventory: Total inventory acquired was approximately $ 712.0 million, which reflects a step-up in the fair value of finished goods and work-in-process inventory for SYFOVRE and EMPAVELI. The fair value was determined based on the estimated selling price of the inventory, 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 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 %. T hese 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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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.
T J 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.
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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. U nder 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 a nd recognized a de minimis loss within our condensed consolidated statements of income for the six months ended June 30, 2025.

Note 4:
Restructuring

Apellis Integration
Following the closing of the Apellis acquisition, we implemented an integration plan designed to realize operating synergies through cost savings and avoidance. For the three and six months ended June 30, 2026, we recognized approximately $ 153.2  million of net pre-tax restructuring charges, primarily consisting of employee severance costs and the acceleration of bonus payments that were subject to a double-trigger provision.
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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   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  

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BIOGEN INC. AND SUBSIDIARIES
NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

Note 5:
Revenue

Product Revenue
Revenue by product is summarized as follows:

  For the Three Months Ended June 30,
2026 2025
(In millions) United
States Rest of
World Total United
States Rest of
World Total
Multiple Sclerosis:
TECFIDERA $ 32.4   $ 58.5   $ 90.9   $ 47.2   $ 146.4   $ 193.6  
VUMERITY 172.0   24.5   196.5   188.0   24.3   212.3  
Total Fumarate 204.4   83.0   287.4   235.2   170.7   405.9  
AVONEX 120.9   49.1   170.0   121.7   56.0   177.7  
PLEGRIDY 25.2   29.9   55.1   28.3   40.7   69.0  
Total Interferon 146.1   79.0   225.1   150.0   96.7   246.7  
TYSABRI 270.5   180.3   450.8   272.2   182.4   454.6  
Subtotal: Multiple Sclerosis 621.0   342.3   963.3   657.4   449.8   1,107.2  

Rare Disease:
SPINRAZA 204.3   197.6   401.9   149.3   243.4   392.7  
SKYCLARYS 82.3   85.6   167.9   78.0   52.3   130.3  
QALSODY 8.3   23.6   31.9   7.5   12.5   20.0  
Subtotal: Rare Disease 294.9   306.8   601.7   234.8   308.2   543.0  

Specialized Immunology:
SYFOVRE (1)
97.4   —   97.4   —   —   —  
EMPAVELI (1)
30.4   —   30.4   —   —   —  
Subtotal: Specialized Immunology 127.8   —   127.8   —   —   —  

Biosimilars:
BENEPALI —   106.8   106.8   —   112.1   112.1  
IMRALDI —   37.8   37.8   —   46.7   46.7  
FLIXABI —   8.1   8.1   —   14.3   14.3  
BYOOVIZ (2)
0.1   —   0.1   2.5   6.1   8.6  

Subtotal: Biosimilars 0.1   152.7   152.8   2.5   179.2   181.7  

Other:
ZURZUVAE 70.7   0.1   70.8   46.4   —   46.4  

Other (3)
—   —   —   —   0.4   0.4  
Subtotal: Other 70.7   0.1   70.8   46.4   0.4   46.8  
Total product revenue, net $ 1,114.5   $ 801.9   $ 1,916.4   $ 941.1   $ 937.6   $ 1,878.7  

(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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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

  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) EMPAVELI and SYFOVRE were obtained as part of our acquisition of Apellis in May 2026.
(3) In 2025 we completed the sale of our rights to TOFIDENCE and BYOOVIZ.
(4) Other includes FUMADERM and ADUHELM.
We 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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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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

(In millions) Discounts Contractual
Adjustments Returns Total
Balance, December 31, 2025 $ 115.7   $ 1,046.1   $ 49.0   $ 1,210.8  
Apellis acquisition 13.3   32.3   6.4   52.0  
Current provisions relating to sales in current year 439.8   1,352.1   13.4   1,805.3  
Adjustments relating to prior years ( 2.0 ) ( 69.2 ) 13.7   ( 57.5 )
Payments/credits relating to sales in current year ( 316.1 ) ( 745.0 ) ( 0.1 ) ( 1,061.2 )
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 June 30, 2026 As of December 31, 2025
Component of accrued expense and other $ 980.2   $ 1,000.4  
Reduction of accounts receivable 262.8   210.4  
Total revenue-related reserves $ 1,243.0   $ 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 June 30, For the Six Months Ended June 30,
(In millions) 2026 2025 2026 2025
Royalty revenue on sales of OCREVUS $ 381.4   $ 353.8   $ 698.6   $ 642.6  
Biogen’s share of pre-tax profits in the U.S. for RITUXAN, GAZYVA and LUNSUMIO 125.7   107.7   220.4   191.4  
Other revenue from anti-CD20 therapeutic programs 6.4   5.8   13.6   11.5  
Total revenue from anti-CD20 therapeutic programs $ 513.5   $ 467.3   $ 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 June 30, 2026, we recognized Alzheimer's collaboration revenue of approximately $ 63.7 million and $ 123.2 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.
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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 arrangements with Samsung Bioepis, Eisai and 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 June 30, 2026 As of December 31, 2025
Raw materials $ 308.0   $ 293.4  
Work in process 1,655.0   1,595.2  
Finished goods 557.0   424.9  
Total inventory $ 2,520.0   $ 2,313.5  

Balance Sheet Classification:
Inventory $ 2,384.3   $ 2,168.1  
Investments and other assets 135.7   145.4  
Total inventory $ 2,520.0   $ 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 Apellis in May 2026, we recorded approximately $ 712.0  million of acquired inventory related to SYFOVRE and EMPAVELI, inclusive of fair value step-up adjustments related to the acquired inventory of SYFOVRE and EMPAVELI totaling approximately $ 567.5  million. We expect these amounts to be fully amortized by the end of 2029. For the three and six months ended June 30, 2026, amortization from the fair value step-up adjustments, which was recorded as a component of cost of sales within our condensed consolidated statements of income, was approximately $ 69.7  million. For additional information on our acquisition of Apellis, please read Note 2, Acquisitions , to these condensed consolidated financial statements.
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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 June 30, 2026 As of December 31, 2025
(In millions) Estimated Life Cost Accumulated
Amortization Net Cost Accumulated
Amortization Net

Completed technology 1 - 30 years
$ 18,708.8   $ ( 6,992.4 ) $ 11,716.4   $ 14,067.3   $ ( 6,687.8 ) $ 7,379.5  
In-process research and development Indefinite until commercialization 1,636.0   —  1,636.0   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 $ 20,508.8   $ ( 6,992.4 ) $ 13,516.4   $ 15,866.3   $ ( 6,687.8 ) $ 9,178.5  

Amortization and Impairments
For the three and six months ended June 30, 2026, amortization and impairment of acquired intangible assets totaled $ 168.2 million and $ 304.7 million, compared to $ 130.9 million and $ 242.7 million, respectively, in the prior year comparative periods.
For the three and six months ended June 30, 2026, amortization of acquired intangible assets, excluding impairment charges, totaled $ 168.2 million and $ 304.7 million, respectively, compared to $ 127.4 million and $ 239.2 million, respectively in the prior year comparative per iods. The increases were primarily due to higher rates of amortization for the acquired intangible assets associated with SKYCLARYS. Additionally, we recorded $ 22.6 million 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. In connection with our acquisition of Apellis we acquired completed technology with an estimated fair value of approximately $ 4.6  billion, 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.
Completed technology intangible assets are amortized over their estimated useful lives, which range between approximately 1 to 30 years, with a remaining weighted average useful life of 13 years as of June 30, 2026.

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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 rollforward of the changes in our goodwill balance:

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

(1) Other includes adjustments related to foreign currency exchange rate fluctuations.
For additional information on our acquisition of Apellis, please read Note 2, Acquisitions , to 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 June 30, 2026
(In millions) Total Quoted Prices
in Active
Markets
(Level 1) Significant
Other Observable
Inputs
(Level 2) Significant
Unobservable
Inputs
(Level 3)
Assets:
Cash equivalents $ 569.4   $ —   $ 569.4   $ —  

Marketable equity securities 184.0   184.0   —   —  
Other current assets:

Derivative contracts 21.6   —   21.6   —  
Other non-current assets:
Convertible notes (1)
35.0   —   —   35.0  
Plan assets for deferred compensation 64.2   —   64.2   —  
Derivative contracts 7.7   —   7.7   —  
Total $ 881.9   $ 184.0   $ 662.9   $ 35.0  
Liabilities:
Other current liabilities:
Derivative contracts $ 26.6   $ —   $ 26.6   $ —  

Other non-current liabilities:

Contingent consideration obligations 273.5   —   —   273.5  
Total $ 300.1   $ —   $ 26.6   $ 273.5  

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

(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 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.
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 nor changes to our valuation techniques as of June 30, 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 June 30, 2026
(In millions) Fair Value Valuation Technique Significant
Unobservable Input(s) Range Weighted Average
Liabilities:
Contingent consideration obligations $ 269.4   Discounted cash flow Discount rate 5.9 %
5.9 %
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 June 30, 2026.
There were no transfers of assets or liabilities into or out of Level 3 as of June 30, 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 June 30, For the Six Months Ended June 30,
(In millions) 2026 2025 2026 2025
Fair value, beginning of period $ 266.9   $ 522.4   $ 246.4   $ 512.8  
Contingent consideration related to the acquisition of Apellis 4.1   —   4.1   —  
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 June 30, 2026 and December 31, 2025, contingent consideration liabilities of $ 273.5 million and $ 246.4 million, respectively, were classified as long-term and reflected as a component of other long-term liabilities in our condensed consolidated balance sheets.
F or the three and six months ended June 30, 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
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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 June 30, 2026 As of December 31, 2025
(In millions) Fair
Value Carrying
Value Fair
Value Carrying
Value
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:
2026 Term Loan two-year tranche (1)
999.9   1,000.0   —   —  
2.250 % Senior Notes due May 1, 2030
1,368.7   1,496.2   1,378.7   1,495.7  
5.050 % Senior Notes due January 15, 2031
404.6   398.1   413.0   398.0  
5.750 % Senior Notes due May 15, 2035
675.1   645.7   684.5   645.5  
5.200 % Senior Notes due September 15, 2045
1,031.3   1,101.7   1,029.5   1,101.5  
3.150 % Senior Notes due May 1, 2050
973.4   1,476.0   973.0   1,475.6  
3.250 % Senior Notes due February 15, 2051
458.9   482.3   461.8   480.3  
6.450 % Senior Notes due May 15, 2055
744.0   690.2   737.6   690.2  
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  

(1) In connection with our acquisition of Apellis 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 . For additional information on our 2026 Term Loan, please read Note 12, Indebtedness , to these condensed consolidated financial statements.
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 June 30, 2026 As of December 31, 2025
Money market funds $ 569.4   $ 2,027.7  
Overnight reverse repurchase agreements —   70.0  

Short-term debt securities —   15.4  
Commercial paper —   120.1  
Total
$ 569.4   $ 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 June 30, 2026
(In millions) Amortized
Cost Gross
Unrealized
Gains Gross
Unrealized
Losses Fair
Value

Marketable equity securities

Marketable equity securities, non-current $ 227.7   $ —   $ ( 43.7 ) $ 184.0  
Total marketable equity securities $ 227.7   $ —   $ ( 43.7 ) $ 184.0  

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  

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 December 31, 2025
(In millions) Estimated
Fair Value Amortized
Cost
Due in one year or less $ 807.2   $ 807.2  
Due after one year through five years 419.5   419.3  
Due after five years 12.4   12.4  
Total marketable debt securities $ 1,239.1   $ 1,238.9  

We funded 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. For additional information on our acquisition of Apellis, please read Note 2, Acquisitions , to these condensed 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:
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(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 June 30, 2026 and December 31, 2025, our strategic investment portfolio was comprised of investments totaling $ 248.7 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 June 30, 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 June 30, 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.
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 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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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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 June 30, 2026 As of December 31, 2025
Unrealized gains $ 13.6   $ —  
Unrealized (losses) ( 10.5 ) ( 73.3 )
Net unrealized gains (losses) $ 3.1   $ ( 73.3 )

We expect net unrealized gains of approximately $ 3.1  million to be settled over the next 18 months , of which approximately $ 1.7  million of 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 June 30, 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 tables summarize the effect of foreign currency forward contracts and forward currency options designated as hedging instruments in our condensed consolidated statements of income:

For the Three Months Ended June 30,
Net Gains/(Losses)
Reclassified from AOCI into Operating Income (in millions) Net Gains/(Losses) Excluded from Effectiveness Testing and
Recognized in Operating Income (in millions)
Location 2026 2025 Location 2026 2025
Revenue $ ( 9.2 ) $ ( 22.9 ) Revenue $ ( 3.0 ) $ ( 0.8 )
Operating expense ( 0.2 ) 6.6   Operating expense ( 0.6 ) ( 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 and
Recognized 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 $ 1,193.3 million and $ 1,193.7 million as of June 30, 2026 and December 31, 2025, respectively. Net losses of $ 11.2 million and $ 30.0 million related to these contracts were recorded as a component of other (income) expense, net for the three and six months ended June 30, 2026, compared to net gains of $ 27.7 million and $ 35.4 million, respectively, in the prior year comparative 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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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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

(In millions) Balance Sheet Location As of June 30, 2026 As of December 31, 2025
Cash Flow Hedging Instruments:
Asset derivative instruments Other current assets $ 17.0   $ 0.1  
Investments and other assets 7.7   0.4  
Liability derivative instruments Accrued expense and other ( 4.6 ) 54.0  
Other long-term liabilities —   2.2  

Other Derivative Instruments:
Asset derivative instruments Other current assets 4.6   9.9  
Liability derivative instruments Accrued expense and other ( 21.9 ) 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 $ 3.1  billion and $ 2.9  billion as of June 30, 2026 and December 31, 2025, respectively. For the three and six months ended June 30, 2026, depreciation expense totaled approximately $ 67.9 million and $ 135.8 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
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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.
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.
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 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 Currency
Translation Adjustments,
Net of Tax Total
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 Currency
Translation 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 )

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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
For the Three Months Ended June 30, For the Six Months Ended June 30,
2026 2025 2026 2025
Gains (losses) on securities available for sale $ ( 1.2 ) $ —   $ ( 1.2 ) $ —   Other (income) expense, net
0.2   —   0.2   —   Income tax (benefit) expense

Gains (losses) on cash flow hedges $ ( 9.2 ) $ ( 22.9 ) $ ( 33.5 ) $ ( 12.0 ) Revenue
( 0.2 ) 6.6   0.5   7.3   Operating expense
—   ( 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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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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 June 30, For the Six Months Ended June 30,
(In millions) 2026 2025 2026 2025
Numerator:
Net income attributable to Biogen Inc. $ 97.5   $ 634.8   $ 417.0   $ 875.3  
Denominator:
Weighted average number of common shares outstanding 147.7   146.5   147.4   146.3  
Effect of dilutive securities:

Time-vested restricted stock units 0.8   0.2   1.0   0.3  

Performance stock units settled in stock 0.2   —   0.2   0.1  
Dilutive potential common shares 1.0   0.2   1.2   0.4  
Shares used in calculating diluted earnings per share 148.7   146.7   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 June 30, For the Six Months Ended June 30,
(In millions) 2026 2025 2026 2025
Research and development
$ 32.3   $ 30.1   $ 67.1   $ 62.2  
Selling, general and administrative 48.0   48.0   101.0   100.0  

Subtotal 80.3   78.1   168.1   162.2  
Capitalized share-based compensation costs ( 3.0 ) ( 3.2 ) ( 6.8 ) ( 6.3 )
Share-based compensation expense included in total cost and expense 77.3   74.9   161.3   155.9  
Income tax effect ( 15.2 ) ( 14.9 ) ( 31.7 ) ( 30.9 )
Share-based compensation expense included in net income attributable to Biogen Inc. $ 62.1   $ 60.0   $ 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 June 30, For the Six Months Ended June 30,
(In millions) 2026 2025 2026 2025
Time-vested restricted stock units $ 66.6   $ 60.6   $ 137.5   $ 126.7  

Performance stock units settled in stock 11.8   15.0   25.1   28.6  
Employee stock purchase plan 1.9   1.6   5.5   5.1  

Stock options —   0.9   —   1.8  

Subtotal 80.3   78.1   168.1   162.2  
Capitalized share-based compensation costs ( 3.0 ) ( 3.2 ) ( 6.8 ) ( 6.3 )
Share-based compensation expense included in total cost and expense $ 77.3   $ 74.9   $ 161.3   $ 155.9  

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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

Note 16:
Income Taxes

Tax Rate
For the three and six months ended June 30, 2026, our effective tax rate was 26.4 % and 18.3 %, respectively, compared to 14.7 % and 17.0 %, respectively, in the prior year comparative periods. The increase in our effective tax rate for the three months ended June 30, 2026 was primarily driven by non-deductible expenses related to our Apellis acquisition and, to a lesser extent, the favorable deferred tax impacts of decreases in foreign withholding taxes recorded in the second quarter of 2025. The six months ended June 30, 2026, compared to the same period in 2025, also reflects favorable impacts of a current year settlement of a foreign tax audit and the vesting 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 June 30, For the Six Months Ended June 30,
(In millions) 2026 2025 2026 2025
Interest income $ ( 25.3 ) $ ( 32.3 ) $ ( 63.2 ) $ ( 56.2 )
Interest expense 82.3   72.6   149.9   132.6  
(Gains) losses on investments, net ( 41.6 ) ( 5.3 ) ( 63.9 ) 30.3  
Litigation related expense ( 0.4 ) 5.2   4.3   8.2  
Foreign exchange (gains) losses, net 6.5   10.4   13.0   6.6  
Other, net ( 3.0 ) ( 1.9 ) ( 1.9 ) ( 4.4 )
Total other (income) expense, net $ 18.5   $ 48.7   $ 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 June 30, For the Six Months Ended June 30,
(In millions) 2026 2025 2026 2025
Net (gains) losses recognized on equity securities $ ( 42.8 ) $ ( 5.3 ) $ ( 65.1 ) $ 30.3  
Less: Net (gains) losses realized on equity securities —   —   ( 3.2 ) ( 5.4 )
Net unrealized (gains) losses recognized on equity securities $ ( 42.8 ) $ ( 5.3 ) $ ( 61.9 ) $ 35.7  

The net unrealized gains recognized during the three months ended June 30, 2026, primarily reflect an increase in the aggregate fair value of our investment in Denali common stock of approximately $ 46.7  million.
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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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 $ 648.9  million and $ 693.6  million as of June 30, 2026 and December 31, 2025, respectively.
Accrued Expense and Other
Accrued expense and other consists of the following:

(In millions) As of June 30, 2026 As of December 31, 2025
Revenue-related reserves for discounts and allowances $ 980.2   $ 1,000.4  
Employee compensation and benefits 391.3   375.8  
Collaboration expense 198.8   280.0  
Royalties and licensing fees 337.8   302.4  

Other 718.2   844.0  
Total accrued expense and other $ 2,626.3   $ 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 $ 820.9 million and $ 748.5 million as of June 30, 2026 and December 31, 2025, respectively, and included accrued income taxes totaling $ 177.5 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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NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)

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.
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.
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BIOGEN INC. AND SUBSIDIARIES
NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
(unaudited, continued)