UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 10-Q

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

For the quarterly period ended March 31, 2024

OR

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

Commission File Number 0-19311

BIOGEN INC.

(Exact name of registrant as specified in its charter)

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

225 Binney Street, Cambridge, MA 02142

(617) 679-2000

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

area code, of registrant’s principal executive offices)

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

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

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

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

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

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

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

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

The number of shares of the issuer’s Common Stock, $0.0005 par value, outstanding as of April 23, 2024, was 145,596,895 shares.

BIOGEN INC.

FORM 10-Q — Quarterly Report

For the Quarterly Period Ended March 31, 2024

TABLE OF CONTENTS

		Page
PART I — FINANCIAL INFORMATION
Item 1.	Financial Statements (unaudited)
	Condensed Consolidated Statements of Income — For the Three Months Ended March 31, 2024 and 2023	7
	Condensed Consolidated Statements of Comprehensive Income — For the Three Months Ended March 31, 2024 and 2023	8
	Condensed Consolidated Balance Sheets — As of March 31, 2024 and December 31, 2023	9
	Condensed Consolidated Statements of Cash Flow — For the Three Months Ended March 31, 2024 and 2023	10
	Condensed Consolidated Statements of Equity — For the Three Months Ended March 31, 2024 and 2023	11
	Notes to Condensed Consolidated Financial Statements	12
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	43
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	65
Item 4.	Controls and Procedures	67
PART II — OTHER INFORMATION
Item 1.	Legal Proceedings	68
Item 1A.	Risk Factors	68
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	83
Item 5.	Other Information	83
Item 6.	Exhibits	84
Signatures		85

2

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 Act) with the intention of obtaining the benefits of the “Safe Harbor” provisions of the Act. These forward-looking statements may be accompanied by such words as “aim,” “anticipate,” “believe,” “could,” "contemplate," "continue," “estimate,” “expect,” “forecast,” "goal," “intend,” “may,” “plan,” “potential,” “possible,” "predict," "project", "should," "target," “will,” “would” or the negative of these words or other words and terms of similar meaning. Reference is made in particular to forward-looking statements regarding:

•the anticipated amount, timing and accounting of revenue; 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;

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

•the potential impact of increased product competition in the 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 or biosimilar versions of our products or competing products;

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

•our plans and investments in our portfolio as well as implementation of our corporate strategy;

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

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

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

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

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

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

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

3

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

•our manufacturing capacity, use of third-party contract manufacturing organizations, plans and timing relating to changes in our manufacturing capabilities, activities in new or existing manufacturing facilities and the expected timeline for the gene therapy 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 collection of accounts receivable in such countries;

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

•the impact of new laws (including tax), regulatory requirements, judicial decisions and accounting standards.

These forward-looking statements involve risks and uncertainties, including those that are described in Item 1A. Risk Factors included in this report and elsewhere in this report, that could cause actual results to differ materially from those reflected in such statements. Because some of these risks and uncertainties cannot be predicted or quantified and some are beyond our control, you should not rely on our forward-looking statements as predictions of future events and you should not place undue reliance on these statements. Moreover, we operate in a very competitive and rapidly changing environment, new risks and uncertainties may emerge from time to time and it is not possible for us to predict all risks nor identify all uncertainties. Forward-looking statements speak only as of the date of this report and are based on information and estimates available to us at this time. Except as required by law, we do not undertake any obligation to publicly update any forward-looking statements, whether as a result of new information, future developments or otherwise. You should read this report with the understanding that our actual future results, performance, events and circumstances might be materially different from what we expect.

NOTE REGARDING COMPANY AND PRODUCT REFERENCES

References in this report to:

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

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

NOTE REGARDING TRADEMARKS

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

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

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

4

DEFINED TERMS

2023 Form 10-K	Annual Report on Form 10-K for the year ended December 31, 2023
2020 Share Repurchase Program	Board of Directors authorized program to repurchase up to $5.0 billion of our common stock
AbbVie	AbbVie Inc.
Acorda	Acorda Therapeutics, Inc.
AI	Artificial Intelligence
Alkermes	Alkermes plc
ALS	Amyotrophic Lateral Sclerosis
AOCI	Accumulated Other Comprehensive Income (Loss)
ASU	Accounting Standards Update
ATV	Antibody Transport Vehicle
BLA	Biologics License Application
Blackstone	Blackstone Life Sciences
CCPA	California Consumer Privacy Act
CHMP	Committee for Medicinal Products for Human Use
CISA	Cybersecurity and Infrastructure Security Agency
CJEU	Court of Justice of the European Union
CLE	Cutaneous Lupus Erythematosus
CLL	Chronic Lymphocytic Leukemia
CLO	Chief Legal Officer
CODM	Chief Operating Decision Maker
Convergence	Convergence Pharmaceuticals Ltd.
CRL	Complete Response Letter
CROs	Contract Research Organizations
DEA	Drug Enforcement Agency
Denali	Denali Therapeutics Inc.
District Court	U.S. District Court for the District of Massachusetts
DOJ	U.S. Department of Justice
EC	European Commission
Eisai	Eisai Co., Ltd.
EMA	European Medicines Agency
EPO	European Patent Office
ERM	Enterprise Risk Management
E.U.	European Union
FA	Friedreich's Ataxia
FASB	Financial Accounting Standards Board
FCPA	Foreign Corrupt Practices Act
FDA	U.S. Food and Drug Administration
FDIC	Federal Deposit Insurance Corporation
Fit for Growth	Cost saving program initiated in 2023
FSS	Federal Supply Schedule
Genentech	Genentech, Inc.
GILTI	Global Intangible Low Tax Income
GloBE	Global Anti-Base Erosion
GMP	Good Manufacturing Practices

5

DEFINED TERMS (continued)

Humana	Humana Inc.
IPR&D	In-process Research and Development
Ionis	Ionis Pharmaceuticals Inc.
IRA	Inflation Reduction Act of 2022
IT	Information Technology
IV	Intravenous
LRRK2	Leucine-Rich Repeat Kinase 2
MAA	Marketing Authorization Application
MDD	Major Depressive Disorder
MS	Multiple Sclerosis
Mylan Ireland	Mylan Ireland Ltd.
NCD	National Coverage Decision
NDA	New Drug Application
Neurimmune	Neurimmune SubOne AG
NMPA	National Medicinal Products Administration
OECD	Organization for Economic Co-operation and Development
OIE	Other (Income) Expense, Net
Polpharma	Polpharma Biologics S.A.
PPACA	Patient Protection and Affordable Care Act
PPD	Postpartum Depression
PPMS	Primary Progressive MS
PRV	Priority Review Voucher
R&D	Research and Development
Reata	Reata Pharmaceuticals, Inc.
RMS	Relapsing MS
RRMS	Relapsing-Remitting MS
RTP	Research Triangle Park
Sage	Sage Therapeutics, Inc.
Samsung Bioepis	Samsung Bioepis Co., Ltd.
Samsung BioLogics	Samsung BioLogics Co., Ltd.
Sangamo	Sangamo Therapeutics, Inc.
SEC	U.S. Securities and Exchange Commission
SG&A	Selling, General and Administrative
SLE	Systemic Lupus Erythematosus
SMA	Spinal Muscular Atrophy
SMN	Survival Motor Neuron
SOD1	Superoxide Dismutase 1
SWISSMEDIC	Swiss Agency for Therapeutic Products
TBA	Technical Boards of Appeal
Transition Toll Tax	A one-time mandatory deemed repatriation tax on accumulated foreign subsidiaries' previously untaxed foreign earnings
U.K.	United Kingdom
U.S.	United States
U.S. GAAP	Accounting Principles Generally Accepted in the U.S.
VA	Veterans Administration

6

PART I FINANCIAL INFORMATION

BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF INCOME

(unaudited, in millions, except per share amounts)

	For the Three Months Ended March 31,
	2024		2023
Revenue:
Product, net	$	1,711.9	$	1,763.3
Revenue from anti-CD20 therapeutic programs	394.0		399.5
Contract manufacturing, royalty and other revenue	184.6		300.2
Total revenue	2,290.5		2,463.0
Cost and expense:
Cost of sales, excluding amortization and impairment of acquired intangible assets	542.2		662.8
Research and development	452.9		570.6
Selling, general and administrative	581.5		605.0
Amortization and impairment of acquired intangible assets	78.3		50.2
Collaboration profit sharing/(loss reimbursement)	65.6		57.1
Restructuring charges	11.5		9.6
Other (income) expense, net	93.7		69.4
Total cost and expense	1,825.7		2,024.7
Income before income tax (benefit) expense	464.8		438.3
Income tax (benefit) expense	71.4		50.7
Net income	393.4		387.6
Net income (loss) attributable to noncontrolling interests, net of tax	—		(0.3)
Net income attributable to Biogen Inc.	$	393.4	$	387.9
Net income per share:
Basic earnings per share attributable to Biogen Inc.	$	2.71	$	2.69
Diluted earnings per share attributable to Biogen Inc.	$	2.70	$	2.67
Weighted-average shares used in calculating:
Basic earnings per share attributable to Biogen Inc.	145.2		144.4
Diluted earnings per share attributable to Biogen Inc.	145.9		145.2

See accompanying notes to these unaudited condensed consolidated financial statements.

7

BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME

(unaudited, in millions)

	For the Three Months Ended March 31,
	2024		2023
Net income (loss) attributable to Biogen Inc.	$	393.4	$	387.9
Other comprehensive income:
Unrealized gains (losses) on securities available for sale, net of tax	—		5.7
Unrealized gains (losses) on cash flow hedges, net of tax	14.7		(35.4)
Unrealized gains (losses) on pension benefit obligation, net of tax	(0.1)		0.5
Currency translation adjustment	(21.4)		22.1
Total other comprehensive income (loss), net of tax	(6.8)		(7.1)
Comprehensive income (loss) attributable to Biogen Inc.	386.6		380.8
Comprehensive income (loss) attributable to noncontrolling interests, net of tax	—		(0.3)
Comprehensive income (loss)	$	386.6	$	380.5

See accompanying notes to these unaudited condensed consolidated financial statements.

8

BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED BALANCE SHEETS

(unaudited, in millions, except per share amounts)

 

	As of March 31, 2024		As of December 31, 2023
ASSETS
Current assets:
Cash and cash equivalents	$	1,074.4	$	1,049.9
Accounts receivable, net of allowance for doubtful accounts of $2.2 and $2.4, respectively	1,604.5		1,664.1
Due from anti-CD20 therapeutic programs	395.2		435.9
Inventory	2,516.8		2,527.4
Other current assets	1,165.3		1,182.0
Total current assets	6,756.2		6,859.3
Property, plant and equipment, net	3,275.3		3,309.7
Operating lease assets	428.1		420.0
Intangible assets, net	8,284.7		8,363.0
Goodwill	6,227.4		6,219.2
Deferred tax asset	898.3		928.6
Investments and other assets	697.6		745.0
Total assets	$	26,567.6	$	26,844.8
LIABILITIES AND EQUITY
Current liabilities:
Current portion of term loan	$	250.0	$	150.0
Taxes payable	231.2		257.4
Accounts payable	387.0		403.3
Accrued expense and other	2,354.6		2,623.6
Total current liabilities	3,222.8		3,434.3
Notes payable and term loan	6,290.1		6,788.2
Deferred tax liability	658.1		641.8
Long-term operating lease liabilities	406.5		400.0
Other long-term liabilities	777.1		781.1
Total liabilities	11,354.6		12,045.4
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	329.5		302.5
Accumulated other comprehensive income (loss)	(160.5)		(153.7)
Retained earnings	18,021.0		17,627.6
Treasury stock, at cost	(2,977.1)		(2,977.1)
Total equity	15,213.0		14,799.4
Total liabilities and equity	$	26,567.6	$	26,844.8

See accompanying notes to these unaudited condensed consolidated financial statements.

9

BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOW

(unaudited, in millions)

	For the Three Months Ended March 31,
	2024		2023
Cash flow from operating activities:
Net income	$	393.4	$	387.6
Adjustments to reconcile net income to net cash flow from operating activities:
Depreciation and amortization	147.5		112.3
Excess and obsolescence charges related to inventory	27.5		17.4
Amortization of inventory step-up	44.1		—
Share-based compensation	72.8		75.6
Deferred income taxes	39.9		(64.5)
(Gain) loss on strategic investments	31.3		79.6
Other	25.4		31.4
Changes in operating assets and liabilities, net of effects of business acquired:
Accounts receivable	43.7		77.2
Due from anti-CD20 therapeutic programs	40.7		37.6
Inventory	(77.7)		27.9
Accrued expense and other current liabilities	(177.1)		(295.0)
Income tax assets and liabilities	(2.2)		65.0
Other changes in operating assets and liabilities, net	(56.1)		(96.8)
Net cash flow provided by (used in) operating activities	553.2		455.3
Cash flow from investing activities:
Purchases of property, plant and equipment	(45.9)		(66.6)
Proceeds from sales and maturities of marketable securities	—		406.7
Purchases of marketable securities	—		(1,321.2)
Acquisitions of intangible assets	(75.0)		(5.0)
Proceeds from sales of strategic investments	55.6		33.8
Other	(0.7)		(0.7)
Net cash flow provided by (used in) investing activities	(66.0)		(953.0)
Cash flow from financing activities:
Payments related to issuance of stock for share-based compensation arrangements, net	(46.9)		(60.1)
Repayment of borrowings and premiums paid	(400.0)		—
Net (distribution) contribution to noncontrolling interest	—		0.2
Other	7.3		16.5
Net cash flow provided by (used in) financing activities	(439.6)		(43.4)
Net increase (decrease) in cash and cash equivalents	47.6		(541.1)
Effect of exchange rate changes on cash and cash equivalents	(23.1)		20.0
Cash and cash equivalents, beginning of the period	1,049.9		3,419.3
Cash and cash equivalents, end of the period	$	1,074.4	$	2,898.2

See accompanying notes to these unaudited condensed consolidated financial statements.

10

BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY

(unaudited, in millions)

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

	December 31, 2023
	Preferred stock			Common stock			Additional paid-in capital		Accumulated other comprehensive loss		Retained earnings		Treasury stock			Total Biogen Inc. shareholders’ equity		Noncontrolling interests		Total equity
	Shares	Amount		Shares	Amount								Shares	Amount
Balance, December 31, 2022	—	$	—	167.9	$	0.1	$	73.3	$	(164.9)	$	16,466.5	(23.8)	$	(2,977.1)	$	13,397.9	$	(9.5)	$	13,388.4
Net income	—	—		—	—		—		—		387.9		—	—		387.9		(0.3)		387.6
Other comprehensive income (loss), net of tax	—	—		—	—		—		(7.1)		—		—	—		(7.1)		—		(7.1)
Capital contribution from noncontrolling interest	—	—		—	—		—		—		—		—	—		—		0.2		0.2
Issuance of common stock under stock option and stock purchase plans	—	—		0.1	—		20.1		—		—		—	—		20.1		—		20.1
Issuance of common stock under stock award plan	—	—		0.6	—		(80.2)		—		—		—	—		(80.2)		—		(80.2)
Compensation related to share-based payments	—	—		—	—		78.9		—		—		—	—		78.9		—		78.9
Other	—	—		—	—		(0.9)		—		—		—	—		(0.9)		—		(0.9)
Balance, March 31, 2023	—	$	—	168.6	$	0.1	$	91.2	$	(172.0)	$	16,854.4	(23.8)	$	(2,977.1)	$	13,796.6	$	(9.6)	$	13,787.0

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 worldwide. We have a broad portfolio of medicines to treat MS, have introduced the first approved treatment for SMA, co-developed treatments to address a defining pathology of Alzheimer’s disease and launched the first approved treatment to target a genetic cause of ALS. Through our 2023 acquisition of Reata we market the first and only drug approved in the U.S. and the E.U. for the treatment of Friedreich's Ataxia in adults and adolescents aged 16 years and older. We are focused on advancing our pipeline in neurology, specialized immunology and rare diseases. We support our drug discovery and development efforts through internal research and development programs and external collaborations.

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

We also have collaborations with Eisai on the commercialization of LEQEMBI for the treatment of Alzheimer's disease and Sage on the commercialization of ZURZUVAE for the treatment of PPD and we have certain business and financial rights with respect to RITUXAN for the treatment of non-Hodgkin's lymphoma, CLL and other conditions; RITUXAN HYCELA for the treatment of non-Hodgkin's lymphoma and CLL; GAZYVA for the treatment of CLL and follicular lymphoma; OCREVUS for the treatment of PPMS and RMS; LUNSUMIO for the treatment of relapsed or refractory follicular lymphoma; COLUMVI, a bispecific antibody for the treatment of non-Hodgkin's lymphoma; and have the option to add other potential anti-CD20 therapies, pursuant to our collaboration arrangements with Genentech, a wholly-owned member of the Roche Group.

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

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

Basis of Presentation

In the opinion of management, our condensed consolidated financial statements include all adjustments, consisting of normal recurring accruals, necessary for a fair statement of our financial statements for interim periods in accordance with U.S. GAAP. The information included in this quarterly report on Form 10-Q should be read in conjunction with our audited consolidated financial statements and the accompanying notes included in our 2023 Form 10-K. Our accounting policies are described in the Notes to Consolidated Financial Statements in our 2023 Form 10-K and updated, as necessary, in this report. The year-end condensed consolidated balance sheet data presented for comparative purposes was derived from our audited financial statements, but does not include all disclosures required by U.S. GAAP. The results of operations for the three months ended March 31, 2024, 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 worldwide innovative therapies for people living with serious neurological and neurodegenerative diseases as well as related therapeutic adjacencies.

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(unaudited, continued)

Consolidation

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

In determining whether we are the primary beneficiary of a variable interest entity, we apply a qualitative approach that determines whether we have both (1) the power to direct the economically significant activities of the entity and (2) the obligation to absorb losses of, or the right to receive benefits from, the entity that could potentially be significant to that entity. We continuously assess whether we are the primary beneficiary of a variable interest entity as changes to existing relationships or future transactions may result in us consolidating or deconsolidating one or more of our collaborators or partners. In November 2023 we terminated the Neurimmune Agreement, which resulted in the deconsolidation of our variable interest entity, Neurimmune. For additional information on the deconsolidation of Neurimmune, please read Note 20, Investments in Variable Interest Entities, to these condensed consolidated financial statements.

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 2023 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.

Climate-Related Disclosures

In March 2024 the SEC issued a final rule under SEC Release No. 33-11275, The Enhancement and Standardization of Climate-Related Disclosures for Investors. This new rule will require large accelerated filers to disclose material climate-related risks that are reasonably likely to have a material impact on its business, results of operations or financial condition. The required information about climate-related risks will also include disclosure of material direct greenhouse gas emissions from operations owned or controlled (Scope 1) and/or material indirect greenhouse gas emissions from purchased energy consumed in owned or controlled operations (Scope 2). Additionally, the new rules will require disclosure within the notes to the financial statements of the effects of severe weather events and other natural conditions and information on any climate-related targets or goals, subject to certain materiality thresholds. The final rule, if adopted, includes a phased-in compliance period which will begin phasing in with our annual report for the year ending December 31, 2025.

In April 2024 the SEC voluntarily stayed implementation of the new climate-related disclosure requirements pending judicial review. We are currently evaluating the potential impact that this new rule will have on our company's disclosures.

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(unaudited, continued)

Segment Reporting

In November 2023 the FASB issued ASU No. 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosure. This standard requires disclosure of significant segment expenses that are regularly provided to the CODM and included within each reported measure of segment profit or loss, an amount and description of its composition for other segment items to reconcile to segment profit or loss and the title and position of the entity's CODM. The amendments in this update also expand the interim segment disclosure requirements. All disclosure requirements under this standard are also required for public entities with a single reportable segment. This standard is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. Early adoption is permitted and the amendments in this update are required to be applied on a retrospective basis. We are currently evaluating the potential impact that this new standard will have on our condensed consolidated financial statements and related disclosures.

Note 2: Acquisitions

Reata Pharmaceuticals, Inc.

On September 26, 2023, we completed the acquisition of all of the issued and outstanding shares of Reata, a biopharmaceutical company focused on developing therapeutics that regulate cellular metabolism and inflammation in serious neurologic diseases. As a result of this transaction we acquired SKYCLARYS (omaveloxolone), the first and only drug approved in the U.S. and the E.U. for the treatment of Friedreich's Ataxia in adults and adolescents aged 16 years and older, as well as other clinical and preclinical pipeline programs. The acquisition of Reata is expected to complement our global portfolio of neuromuscular and rare disease therapies. The addition of SKYCLARYS is anticipated to provide potential operating synergies with SPINRAZA and QALSODY.

Under the terms of this acquisition, we paid Reata shareholders $172.50 in cash for each issued and outstanding Reata share, which totaled approximately $6.6 billion. In addition, we agreed to pay approximately $983.9 million in cash for Reata's outstanding equity awards, inclusive of employer taxes, of which approximately $590.5 million was attributable to pre-acquisition services and is therefore reflected as a component of total purchase price paid. Of the $983.9 million paid to Reata's equity award holders, we recognized approximately $393.4 million as compensation attributable to the post-acquisition service period, of which $196.4 million was recognized as a charge to selling, general and administrative expense with the remaining $197.0 million as a charge to research and development expense within our condensed consolidated statements of income for the year ended December 31, 2023. These amounts were associated with the accelerated vesting of stock options and RSUs previously granted to Reata employees and required no future services to vest.

We funded this acquisition through available cash, cash equivalents and marketable securities, supplemented by the issuance of a $1.0 billion term loan under our term loan credit agreement. For additional information on our term loan credit agreement, please read Note 13, 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 Reata is summarized as follows:

(In millions)	As of September 26, 2023
Cash consideration paid to Reata shareholders(1)	$	6,602.9
Fair value of Reata equity compensation pre-acquisition services and related taxes(2)	590.5
Total consideration	$	7,193.4

(1) Represents cash consideration transferred of $172.50 per outstanding Reata ordinary share based on 38.3 million Reata shares outstanding at closing.

(2) Represents the fair value of Reata stock options and stock units issued to Reata equity award holders and the related taxes attributable to pre-acquisition vesting services.

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(unaudited, continued)

Preliminary Purchase Price Allocation

The following table summarizes the provisional amounts recognized for assets acquired and liabilities assumed as of the acquisition date, as well as measurement period adjustments made year-to-date to the amounts initially recorded as of the acquisition date on September 26, 2023. The measurement period adjustments summarized below resulted from updates to our valuation assumptions related to the estimated amounts and timing of future cash flows associated with certain intangible assets, updates of our assumptions related to the quantities, selling location and remaining manufacturing and selling costs of acquired inventory, and other assets and liabilities. The related impact to our condensed consolidated statements of income that would have been recognized in previous periods if the adjustments were recognized as of the acquisition date is immaterial.

(In millions)	Amounts Recognized as of Acquisition Date (as adjusted) March 31, 2024
Cash and cash equivalents	$	267.3
Accounts receivable	15.9
Inventory	1,259.0
Other current assets	53.6
Intangible assets:
Completed technology for SKYCLARYS (U.S.)	4,200.0
In-process research and development (omaveloxolone)	2,300.0
Priority review voucher	100.0
Other clinical programs	40.0
Operating lease assets	121.2
Accrued expense and other(1)	(106.4)
Debt payable	(159.9)
Contingent payable to Blackstone	(300.0)
Deferred tax liability(1)	(916.5)
Operating lease liabilities	(151.8)
Other assets and liabilities, net	(2.5)
Total identifiable net assets	6,719.9
Goodwill(1)	473.5
Total assets acquired and liabilities assumed	$	7,193.4

(1) Includes measurement period adjustments recorded in the first quarter of 2024 that increased accrued expense and other by $4.9 million, deferred tax liability by $4.1 million and goodwill by $9.0 million.

Inventory: Total inventory acquired was approximately $1.3 billion, which reflects a step-up in the fair value of finished goods and work-in-process inventory for SKYCLARYS. 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. This fair value step-up adjustment is being amortized to cost of sales within our condensed consolidated statements of income as the inventory is sold, which is expected to be within approximately 3 years from the acquisition date. For the three months ended March 31, 2024, amortization from the fair value step-up adjustment as a result of inventory sold was approximately $44.1 million.

Intangible assets: Intangible assets are comprised of $4.2 billion related to SKYCLARYS commercialization rights in the U.S., $2.3 billion of IPR&D related to the omaveloxolone program outside the U.S., which had not yet received regulatory approval in the E.U. as of the acquisition date, $100.0 million related to a rare pediatric disease priority voucher which may be used to obtain priority review by the FDA for a future regulatory submission or sold to a third party and $40.0 million related to other clinical programs. The estimated fair values of the program related intangible assets were determined using a multi-period excess earnings method, a form of the income approach, utilizing a discount rate of 14.3% and the estimated fair value of the priority review voucher was based on recent external purchase and sale transactions of similar vouchers.

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(unaudited, continued)

Our valuation of the SKYCLARYS commercialization rights reflects the assumption that, using an economic consumption model, the related $4.2 billion intangible asset will be amortized over its expected economic life.

Upon SKYCLARYS receiving E.U. regulatory approval in February 2024, we began selling the product in certain countries in Europe, and began amortizing the $2.3 billion IPR&D asset related to the program outside the U.S. over its expected economic life using an economic consumption model.

These fair value measurements were based on significant inputs not observable in the market and thus represent Level 3 fair value measurements.

Leases: We assumed responsibility for a single-tenant, build-to-suit building of approximately 327,400 square feet of office and laboratory space located in Plano, Texas, with an initial lease term of 16 years. We recorded a lease liability of approximately $151.8 million, which represents the net present value of rental expense over the remaining lease term of approximately 15 years, with a corresponding right-of-use asset of approximately $121.2 million, which represents our estimate of the fair value for a market participant of the current rental market in the Dallas, Texas area. Included in our estimate of the market rental rate is the value of any leasehold improvements or tenant allowances related to the building. We do not intend to occupy this building and are evaluating opportunities to sublease the property.

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 $473.5 million, which is not deductible for tax purposes. The goodwill recognized from our acquisition of Reata is primarily the result of the deferred tax consequences from the transaction recorded for financial statement purposes.

Acquisition-related expenses: Acquisition-related expense, primarily comprised of regulatory, advisory and legal fees, and other transaction costs, totaled approximately $28.4 million and were recorded within selling, general and administrative expense within our condensed consolidated statements of income for the year ended December 31, 2023.

Assumptions in the Allocations of Purchase Price

The results of operations of Reata, along with the estimated fair values of the assets acquired and liabilities assumed in the Reata acquisition, have been included in our condensed consolidated financial statements since the closing of the Reata acquisition on September 26, 2023.

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

Note 3: Dispositions

Sale of Joint Venture Equity Interest in Samsung Bioepis

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

We elected the fair value option and measured the payments due to us from Samsung BioLogics at fair value. As of March 31, 2024, the estimated fair value of the second deferred payment using a risk-adjusted discount rate of 6.0% was approximately $436.1 million. This payment has been classified as a Level 3 measurement and is reflected in other current assets within our condensed consolidated balance sheets as of March 31, 2024.

For the three months ended March 31, 2024, we recognized a gain of approximately $6.1 million to reflect the change in fair value related to the second deferred payment due to us. For the three months ended March 31, 2023, we recognized gains of approximately $11.1 million and $6.2 million to reflect the changes in fair value related to

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(unaudited, continued)

the first and second deferred payments due to us, respectively. These changes were recorded in other (income) expense, net in our condensed consolidated statements of income.

For additional information on the sale of our equity interest in Samsung Bioepis, please read Note 3, Dispositions, to our consolidated financial statements included in our 2023 Form 10-K.

Note 4: Restructuring

2023 Fit for Growth Restructuring Program

In July 2023 we initiated additional cost saving measures as part of our Fit for Growth program to reduce operating costs, while improving operating efficiency and effectiveness. The Fit for Growth program is expected to generate approximately $1.0 billion in gross operating expense savings by the end of 2025, some of which will be reinvested in various initiatives. The Fit for Growth program is currently estimated to include net headcount reductions of approximately 1,000 employees and we expect to incur restructuring charges ranging from approximately $260.0 million to $280.0 million.

Total charges incurred from our 2023 cost saving initiatives are summarized as follows:

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

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

Reata Integration

Following the close of our Reata acquisition in September 2023, we implemented an integration plan designed to realize operating synergies through cost savings and avoidance. Under this initiative, we estimate we will incur total integration charges ranging from approximately $35.0 million to $40.0 million, related to severance and employment costs, which are expected to be paid by the end of 2024. These amounts were substantially incurred during 2023.

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

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

In connection with our acquisition of Reata we assumed responsibility for a single-tenant, build-to-suit building of approximately 327,400 square feet of office and laboratory space located in Plano, Texas, with an initial lease term of 16 years. We do not intend to occupy this building and are evaluating opportunities to sublease the property.

Charges and spending related to workforce reductions from our 2023 Fit for Growth program and Reata Integration are summarized as follows:

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(unaudited, continued)

	For the Three Months Ended March 31,
(In millions)	2024		2023
Restructuring reserve as of December 31	$	75.4	$	35.9
Expense	11.5		7.1
Payment	(42.2)		(15.6)
Foreign currency and other adjustments	0.8		0.6
Restructuring reserve as of March 31	$	45.5	$	28.0

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(unaudited, continued)

Note 5: Revenue

Product Revenue

Revenue by product is summarized as follows:

	For the Three Months Ended March 31,
	2024						2023
(In millions)	United States		Rest of World		Total		United States		Rest of World		Total
Multiple Sclerosis:
TECFIDERA	$	43.7	$	210.6	$	254.3	$	74.7	$	199.8	$	274.5
VUMERITY	105.9		21.6		127.5		93.5		14.7		108.2
Total Fumarate	149.6		232.2		381.8		168.2		214.5		382.7
AVONEX	111.2		67.3		178.5		102.6		69.8		172.4
PLEGRIDY	28.6		36.5		65.1		29.9		43.3		73.2
Total Interferon	139.8		103.8		243.6		132.5		113.1		245.6
TYSABRI	213.8		217.5		431.3		245.4		227.4		472.8
FAMPYRA	—		19.2		19.2		—		24.1		24.1
Subtotal: Multiple Sclerosis	503.2		572.7		1,075.9		546.1		579.1		1,125.2
Rare Disease:
SPINRAZA	148.5		192.8		341.3		146.7		296.6		443.3
QALSODY(1)	4.4		0.2		4.6		—		—		—
SKYCLARYS(2)	73.0		5.0		78.0		—		—		—
Subtotal: Rare Disease	225.9		198.0		423.9		146.7		296.6		443.3
Biosimilars:
BENEPALI	—		118.7		118.7		—		109.0		109.0
IMRALDI	—		54.8		54.8		—		54.4		54.4
FLIXABI	—		17.8		17.8		—		20.4		20.4
BYOOVIZ(3)	3.7		1.9		5.6		8.2		0.4		8.6
Subtotal: Biosimilars	3.7		193.2		196.9		8.2		184.2		192.4
Other(4)	13.3		1.9		15.2		0.4		2.0		2.4
Total product revenue	$	746.1	$	965.8	$	1,711.9	$	701.4	$	1,061.9	$	1,763.3

(1) QALSODY became commercially available in the U.S. during the second quarter of 2023.

(2) SKYCLARYS was obtained as part of our acquisition of Reata in September 2023. SKYCLARYS became commercially available in the U.S. during the second quarter of 2023 and we began recognizing revenue from SKYCLARYS in the U.S. during the fourth quarter of 2023, subsequent to our acquisition. SKYCLARYS was approved and became commercially available in the E.U. during the first quarter of 2024.

(3) BYOOVIZ became commercially available in certain international markets in 2023.

(4) Other includes FUMADERM, ADUHELM and ZURZUVAE, which became commercially available in the U.S. during the fourth quarter of 2023.

We recognized revenue from two wholesalers accounting for 25.6% and 11.7% of gross product revenue for the three months ended March 31, 2024, and 27.3% and 7.4% of gross product revenue for the three months ended March 31, 2023.

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(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, 2023	$	173.3	$	857.1	$	31.6	$	1,062.0
Current provisions relating to sales in current year	181.5		682.6		5.0		869.1
Adjustments relating to prior years	6.1		(16.9)		5.6		(5.2)
Payments/credits relating to sales in current year	(109.1)		(262.1)		(0.2)		(371.4)
Payments/credits relating to sales in prior years	(94.2)		(358.0)		(5.6)		(457.8)
Balance, March 31, 2024	$	157.6	$	902.7	$	36.4	$	1,096.7

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

(In millions)	As of March 31, 2024		As of December 31, 2023
Reduction of accounts receivable	$	139.7	$	135.5
Component of accrued expense and other	957.0		926.5
Total revenue-related reserves	$	1,096.7	$	1,062.0

Revenue from Anti-CD20 Therapeutic Programs

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

	For the Three Months Ended March 31,
(In millions)	2024		2023
Royalty revenue on sales of OCREVUS	$	302.7	$	283.6
Biogen’s share of pre-tax profits in the U.S. for RITUXAN, GAZYVA and LUNSUMIO	87.1		112.5
Other revenue from anti-CD20 therapeutic programs	4.2		3.4
Total revenue from anti-CD20 therapeutic programs	$	394.0	$	399.5

For additional information on our collaboration arrangements with Genentech, please read Note 19, Collaborative and Other Relationships, to our consolidated financial statements included in this report.

Contract Manufacturing, Royalty and Other Revenue

Contract manufacturing, royalty and other revenue is summarized in the table below.

	For the Three Months Ended March 31,
(In millions)	2024		2023
Contract manufacturing revenue	$	152.2	$	306.9
Royalty and other revenue	32.4		(6.7)
Total contract manufacturing, royalty and other revenue	$	184.6	$	300.2

Contract Manufacturing Revenue

Contract manufacturing revenue primarily reflects amounts earned under contract manufacturing agreements with our strategic customers. During the first quarter of 2023 we began recognizing contract manufacturing revenue for LEQEMBI, upon accelerated approval of LEQEMBI in the U.S. Prior to accelerated approval, our share of contract manufacturing amounts related to LEQEMBI were recognized in research and development expense within our condensed consolidated statements of income.

Royalty and Other Revenue

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

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(unaudited, continued)

Samsung Bioepis and our 50.0% share of LEQEMBI product revenue, net and cost of sales, including royalties, as we are not the principal.

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

Note 6: Inventory

The components of inventory are summarized as follows:

(In millions)	As of March 31, 2024		As of December 31, 2023
Raw materials	$	412.5	$	426.9
Work in process	1,851.3		1,926.8
Finished goods	347.9		255.4
Total inventory	$	2,611.7	$	2,609.1
Balance Sheet Classification:
Inventory	$	2,516.8	$	2,527.4
Investments and other assets	94.9		81.7
Total inventory	$	2,611.7	$	2,609.1

We recorded approximately $1.3 billion of acquired inventory, which includes measurement period adjustments, related to SKYCLARYS as a result of our acquisition of Reata in September 2023. 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. This fair value step-up adjustment is being 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. For the three months ended March 31, 2024, amortization from the fair value step-up adjustment as a result of inventory sold was approximately $44.1 million. For additional information on our acquisition of Reata, please read Note 2, Acquisitions, to these condensed consolidated financial statements.

Note 7: Intangible Assets and Goodwill

Intangible Assets

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

		As of March 31, 2024						As of December 31, 2023
(In millions)	Estimated Life	Cost		Accumulated Amortization		Net		Cost		Accumulated Amortization		Net
Completed technology:
Acquired and in-licensed rights and patents	2-22 years	$	10,480.2	$	(2,514.0)	$	7,966.2	$	8,180.2	$	(2,440.7)	$	5,739.5
Developed technology and other	13-31 years	3,548.6		(3,434.1)		114.5		3,548.6		(3,429.1)		119.5
Total completed technology		14,028.8		(5,948.1)		8,080.7		11,728.8		(5,869.8)		5,859.0
In-process research and development	Indefinite until commercialization	40.0		—		40.0		2,340.0		—		2,340.0
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		$	14,232.8	$	(5,948.1)	$	8,284.7	$	14,232.8	$	(5,869.8)	$	8,363.0

Amortization and Impairments

For the three months ended March 31, 2024, amortization and impairment of acquired intangible assets totaled $78.3 million, compared to $50.2 million in the prior year comparative period. The increase was primarily due to

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(unaudited, continued)

amortization for the Reata acquisition acquired intangible assets associated with SKYCLARYS. For the three months ended March 31, 2024 and 2023, we had no impairment charges.

Completed Technology

Completed technology primarily relates to our other marketed products and programs acquired through asset acquisitions, licenses and business combinations. Completed technology intangible assets are amortized over their estimated useful lives, which range between 2 to 31 years, with a remaining weighted average useful life of 12 years for acquired and in-licensed rights and patents and 10 years for developed technology and other. In connection with our acquisition of Reata in September 2023 we acquired SKYCLARYS, a commercially-approved product in the U.S., with an estimated fair value of approximately $4.2 billion, which includes measurement period adjustments. During the first quarter of 2024 SKYCLARYS was approved in the E.U. and became commercially available, which resulted in the reclassification of the related intangible asset, with an estimated fair value of approximately $2.3 billion, from IPR&D to completed technology.

IPR&D Related to Business Combinations

IPR&D represents the fair value assigned to research and development assets that we acquired as part of a business combination and had not yet reached technological feasibility at the date of acquisition. Included in IPR&D balances are adjustments related to foreign currency exchange rate fluctuations. The carrying value associated with our IPR&D assets as of December 31, 2023, related to the IPR&D programs we acquired in connection with our acquisition of Reata in September 2023, with an estimated fair value of approximately $2.3 billion, which includes measurement period adjustments. During the first quarter of 2024 SKYCLARYS was approved in the E.U. and became commercially available, which resulted in the reclassification of the related intangible asset from IPR&D to completed technology.

Priority Review Voucher

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

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

Estimated Future Amortization of Intangible Assets

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

(In millions)	As of March 31, 2024
2024 (remaining nine months)	$	265.0
2025	565.0
2026	660.0
2027	685.0
2028	710.0
2029	715.0

Goodwill

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

(In millions)	As of March 31, 2024
Goodwill, December 31, 2023	$	6,219.2
Goodwill resulting from Reata acquisition	9.0
Other	(0.8)
Goodwill, March 31, 2024	$	6,227.4

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

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BIOGEN INC. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

As of March 31, 2024, we had no accumulated impairment losses related to goodwill. Other includes adjustments related to foreign currency exchange rate fluctuations.

Note 8: Fair Value Measurements

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

	Fair Value Measurements on a Recurring Basis
	As of March 31, 2024
(In millions)	Total		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Cash equivalents	$	484.8	$	—	$	484.8	$	—
Marketable equity securities	329.5		329.5		—		—
Other current assets:
Receivable from Samsung BioLogics(1)	436.1		—		—		436.1
Derivative contracts	9.9		—		9.9		—
Other non-current assets:
Plan assets for deferred compensation	39.0		—		39.0		—
Total	$	1,299.3	$	329.5	$	533.7	$	436.1
Liabilities:
Derivative contracts	$	27.3	$	—	$	27.3	$	—
Total	$	27.3	$	—	$	27.3	$	—

(1) Represents the fair value of the current payment due from Samsung BioLogics as a result of the sale of our 49.9% equity interest in Samsung Bioepis to Samsung BioLogics during the second quarter of 2022, for which we elected the fair value option. For additional information on the sale of our equity interest in Samsung Bioepis, please read Note 3, Dispositions, to these condensed consolidated financial statements.

During the third quarter of 2023 we sold all of our marketable debt securities and used the proceeds to partially fund our acquisition of Reata. For additional information on our acquisition of Reata, please read Note 2, Acquisitions, to these condensed consolidated financial statements.

23

BIOGEN INC. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

	Fair Value Measurements on a Recurring Basis
	As of December 31, 2023
(In millions)	Total		Quoted Prices in Active Markets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Assets:
Cash equivalents	$	610.7	$	—	$	610.7	$	—
Marketable equity securities	416.8		416.8		—		—
Other current assets:
Receivable from Samsung BioLogics(1)	430.0		—		—		430.0
Derivative contracts	11.9		—		11.9		—
Other non-current assets:
Plan assets for deferred compensation	37.5		—		37.5		—
Total	$	1,506.9	$	416.8	$	660.1	$	430.0
Liabilities:
Derivative contracts