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 September 30, 2023

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 November 7, 2023, was 144,898,112 shares.

BIOGEN INC.

FORM 10-Q — Quarterly Report

For the Quarterly Period Ended September 30, 2023

TABLE OF CONTENTS

		Page
PART I — FINANCIAL INFORMATION
Item 1.	Financial Statements (unaudited)
	Condensed Consolidated Statements of Income — For the Three and Nine Months Ended September 30, 2023 and 2022	7
	Condensed Consolidated Statements of Comprehensive Income — For the Three and Nine Months Ended September 30, 2023 and 2022	8
	Condensed Consolidated Balance Sheets — As of September 30, 2023 and December 31, 2022	9
	Condensed Consolidated Statements of Cash Flow — For the Nine Months Ended September 30, 2023 and 2022	10
	Condensed Consolidated Statements of Equity — For the Three and Nine Months Ended September 30, 2023 and 2022	11
	Notes to Condensed Consolidated Financial Statements	15
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	51
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	80
Item 4.	Controls and Procedures	82
PART II — OTHER INFORMATION
Item 1.	Legal Proceedings	83
Item 1A.	Risk Factors	83
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	98
Item 5.	Other Information	98
Item 6.	Exhibits	99
Signatures		100

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,” “estimate,” “expect,” “forecast,” "goal," “intend,” “may,” “plan,” “potential,” “possible,” “will,” “would” and 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 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 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 the COVID-19 pandemic and other global health outbreaks on our business and operations, including sales, expense, reserves and allowances, the supply chain, manufacturing, cyber-attacks or other privacy or data security incidents, research and development costs, clinical trials and employees;

•the current and potential impacts of the conflict in Ukraine, including impacts on our operations, sales and the possible disruptions or delays in our plans to conduct clinical trial activities in affected regions;

•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

3

timeline for the remaining portion of the Solothurn manufacturing facility to begin manufacturing products or product candidates and 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. You should not place undue reliance on these statements. Forward-looking statements speak only as of the date of this report. 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.

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®, 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

2022 Form 10-K	Annual Report on Form 10-K for the year ended December 31, 2022
2020 Share Repurchase Program	Board of Directors authorized program to repurchase up to $5.0 billion of our common stock
300 Binney Street	300 Binney Street, Cambridge, MA
AI	Artificial Intelligence
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
cGMP	current Good Manufacturing Practices
CJEU	Court of Justice of the European Union
CLE	Cutaneous Lupus Erythematosus
CLL	Chronic Lymphocytic Leukemia
CMS	Centers for Medicare & Medicaid Services
Convergence	Convergence Pharmaceuticals Ltd.
CRL	Complete Response Letter
CROs	Contract Research Organizations
DEA	Drug Enforcement Agency
Denali	Denali Therapeutics Inc.
DPN	Diabetic Painful Neuropathy
EC	European Commission
Eisai	Eisai Co., Ltd.
EMA	European Medicines Agency
ERISA	Employee Retirement Income Security Act of 1974
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
Genentech	Genentech, Inc.
GILTI	Global Intangible Low Tax Income
GloBE	Global Anti-Base Erosion
GMP	Good Manufacturing Practice
Humana	Humana Inc.
IPR&D	In-process Research and Development
Ionis	Ionis Pharmaceuticals Inc.
IRA	Inflation Reduction Act of 2022
LRRK2	Leucine-Rich Repeat Kinase 2

5

DEFINED TERMS (continued)

MAA	Marketing Authorization Application
MDD	Major Depressive Disorder
MHRA	Medicines and Healthcare products Regulatory Agency
MS	Multiple Sclerosis
Mylan Ireland	Mylan Ireland Ltd.
NCD	National Coverage Decision
NDA	New Drug Application
NDS	New Drug Submission
Neurimmune	Neurimmune SubOne AG
NMPA	National Medicinal Products Administration
OECD	Organization for Economic Co-operation and Development
Polpharma	Polpharma Biologics S.A.
PPACA	Patient Protection and Affordable Care Act
PPD	Postpartum Depression
PPMS	Primary Progressive MS
R&D	Research and Development
Reata	Reata Pharmaceuticals, Inc.
RMS	Relapsing 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.
SG&A	Selling, General and Administrative
SLE	Systemic Lupus Erythematosus
SMA	Spinal Muscular Atrophy
SOD1	Superoxide Dismutase 1
SVB	Silicon Valley Bank
SWISSMEDIC	Swiss Agency for Therapeutic Products
TGN	Trigeminal Neuralgia
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.

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 September 30,				For the Nine Months Ended September 30,
	2023		2022		2023		2022
Revenue:
Product, net	$	1,805.2	$	1,962.1	$	5,414.3	$	6,083.3
Revenue from anti-CD20 therapeutic programs	420.9		416.9		1,253.8		1,252.6
Contract manufacturing, royalty and other revenue	304.2		129.5		781.2		293.5
Total revenue	2,530.3		2,508.5		7,449.3		7,629.4
Cost and expense:
Cost of sales, excluding amortization and impairment of acquired intangible assets	659.6		469.5		1,915.1		1,707.4
Research and development	736.3		549.2		1,891.1		1,629.5
Selling, general and administrative	788.2		563.3		1,941.2		1,770.8
Amortization and impairment of acquired intangible assets	60.9		56.5		164.0		190.9
Collaboration profit sharing/(loss reimbursement)	50.5		45.3		164.5		(42.6)
(Gain) loss on fair value remeasurement of contingent consideration	—		(2.1)		—		(13.7)
Restructuring charges	76.0		15.4		120.0		124.1
Gain on sale of building	—		(503.7)		—		(503.7)
Other (income) expense, net	300.0		(56.0)		248.2		(221.3)
Total cost and expense	2,671.5		1,137.4		6,444.1		4,641.4
Income (loss) before income tax (benefit) expense and equity in loss of investee, net of tax	(141.2)		1,371.1		1,005.2		2,988.0
Income tax (benefit) expense	(72.9)		236.2		92.6		578.5
Equity in (income) loss of investee, net of tax	—		—		—		(2.6)
Net income (loss)	(68.3)		1,134.9		912.6		2,412.1
Net income (loss) attributable to noncontrolling interests, net of tax	(0.2)		0.2		1.2		(84.4)
Net income (loss) attributable to Biogen Inc.	$	(68.1)	$	1,134.7	$	911.4	$	2,496.5
Net income (loss) per share:
Basic earnings (loss) per share attributable to Biogen Inc.	$	(0.47)	$	7.86	$	6.30	$	17.12
Diluted earnings (loss) per share attributable to Biogen Inc.	$	(0.47)	$	7.84	$	6.26	$	17.07
Weighted-average shares used in calculating:
Basic earnings (loss) per share attributable to Biogen Inc.	144.8		144.4		144.7		145.8
Diluted earnings (loss) per share attributable to Biogen Inc.	144.8		144.8		145.5		146.2

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 September 30,				For the Nine Months Ended September 30,
	2023		2022		2023		2022
Net income (loss) attributable to Biogen Inc.	$	(68.1)	$	1,134.7	$	911.4	$	2,496.5
Other comprehensive income:
Unrealized gains (losses) on securities available for sale, net of tax	14.5		(1.0)		15.7		(19.0)
Unrealized gains (losses) on cash flow hedges, net of tax	29.6		5.9		1.1		79.0
Gains (losses) on net investment hedges, net of tax	—		—		—		(25.5)
Unrealized gains (losses) on pension benefit obligation, net of tax	(0.1)		1.5		0.6		4.2
Currency translation adjustment	(30.5)		(59.6)		(11.8)		(95.6)
Total other comprehensive income (loss), net of tax	13.5		(53.2)		5.6		(56.9)
Comprehensive income (loss) attributable to Biogen Inc.	(54.6)		1,081.5		917.0		2,439.6
Comprehensive income (loss) attributable to noncontrolling interests, net of tax	(0.2)		0.2		1.2		(84.4)
Comprehensive income (loss)	$	(54.8)	$	1,081.7	$	918.2	$	2,355.2

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 September 30, 2023		As of December 31, 2022
ASSETS
Current assets:
Cash and cash equivalents	$	2,287.9	$	3,419.3
Marketable securities	—		1,473.5
Accounts receivable, net	1,781.4		1,705.0
Due from anti-CD20 therapeutic programs	428.3		431.4
Inventory	2,982.4		1,344.4
Other current assets	974.1		1,417.6
Total current assets	8,454.1		9,791.2
Marketable securities	0.1		705.7
Property, plant and equipment, net	3,301.6		3,298.6
Operating lease assets	460.9		403.9
Intangible assets, net	7,344.6		1,850.1
Goodwill	6,807.5		5,749.0
Deferred tax asset	1,069.8		1,226.4
Investments and other assets	754.6		1,529.2
Total assets	$	28,193.2	$	24,554.1
LIABILITIES AND EQUITY
Current liabilities:
Current portion of term loan	$	500.0	$	—
Taxes payable	243.8		259.9
Accounts payable	440.1		491.5
Accrued expense and other	3,838.4		2,521.4
Total current liabilities	5,022.3		3,272.8
Notes payable and term loan	6,786.4		6,281.0
Deferred tax liability	728.1		334.7
Long-term operating lease liabilities	428.8		333.0
Other long-term liabilities	747.9		944.2
Total liabilities	13,713.5		11,165.7
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	242.2		73.3
Accumulated other comprehensive income (loss)	(159.3)		(164.9)
Retained earnings	17,377.9		16,466.5
Treasury stock, at cost	(2,977.1)		(2,977.1)
Total Biogen Inc. shareholders’ equity	14,483.8		13,397.9
Noncontrolling interests	(4.1)		(9.5)
Total equity	14,479.7		13,388.4
Total liabilities and equity	$	28,193.2	$	24,554.1

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 Nine Months Ended September 30,
	2023		2022
Cash flow from operating activities:
Net income	$	912.6	$	2,412.1
Adjustments to reconcile net income to net cash flow from operating activities:
Depreciation and amortization	354.7		398.6
Excess and obsolescence charges related to inventory	62.1		321.6
Share-based compensation	209.3		186.9
Contingent consideration	—		(13.7)
Deferred income taxes	(377.7)		(139.8)
(Gain) loss on strategic investments	275.7		160.3
(Gain) loss on equity method investments	—		(2.6)
Gain on sale of equity interest in Samsung Bioepis	—		(1,505.4)
Gain on sale of building	—		(503.7)
Other	98.6		147.8
Changes in operating assets and liabilities, net of effects of business acquired:
Accounts receivable	(76.5)		(109.5)
Due from anti-CD20 therapeutic programs	3.1		(3.0)
Inventory	(34.9)		(338.3)
Accrued expense and other current liabilities	293.9		632.3
Income tax assets and liabilities	(114.8)		(100.2)
Other changes in operating assets and liabilities, net	(71.4)		15.9
Net cash flow provided by (used in) operating activities	1,534.7		1,559.3
Cash flow from investing activities:
Purchases of property, plant and equipment	(211.8)		(153.9)
Proceeds from sales and maturities of marketable securities	7,380.8		3,104.7
Purchases of marketable securities	(5,140.7)		(2,805.9)
Acquisition of Reata, net of cash acquired	(6,335.6)		—
Proceeds from sale of equity interest in Samsung Bioepis	788.1		990.3
Proceeds from sale of building	—		582.6
Acquisitions of intangible assets	(34.4)		(1.9)
Proceeds from sales of strategic investments	106.2		—
Other	(1.3)		1.8
Net cash flow provided by (used in) investing activities	(3,448.7)		1,717.7
Cash flow from financing activities:
Purchases of treasury stock	—		(750.0)
Payments related to issuance of stock for share-based compensation arrangements, net	(48.0)		(5.8)
Repayment of borrowings and premiums paid	(159.9)		(1,002.2)
Proceeds from borrowings, net	997.2		—
Net (distribution) contribution to noncontrolling interest	4.2		12.2
Other	1.9		5.9
Net cash flow provided by (used in) financing activities	795.4		(1,739.9)
Net increase (decrease) in cash and cash equivalents	(1,118.6)		1,537.1
Effect of exchange rate changes on cash and cash equivalents	(12.8)		(122.9)
Cash and cash equivalents, beginning of the period	3,419.3		2,261.4
Cash and cash equivalents, end of the period	$	2,287.9	$	3,675.6

See accompanying notes to these unaudited condensed consolidated financial statements.

10

BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY

(unaudited, in millions)

	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, June 30, 2023	—	$	—	168.6	$	0.1	$	170.7	$	(172.8)	$	17,446.0	(23.8)	$	(2,977.1)	$	14,466.9	$	(6.4)	$	14,460.5
Net loss	—	—		—	—		—		—		(68.1)		—	—		(68.1)		(0.2)		(68.3)
Other comprehensive income (loss), net of tax	—	—		—	—		—		13.5		—		—	—		13.5		—		13.5
Capital contribution from noncontrolling interest	—	—		—	—		—		—		—		—	—		—		2.5		2.5
Issuance of common stock under stock option and stock purchase plans	—	—		0.1	—		9.3		—		—		—	—		9.3		—		9.3
Issuance of common stock under stock award plan	—	—		—	—		(2.7)		—		—		—	—		(2.7)		—		(2.7)
Compensation related to share-based payments	—	—		—	—		64.8		—		—		—	—		64.8		—		64.8
Other	—	—		—	—		0.1		—		—		—	—		0.1		—		0.1
Balance, September 30, 2023	—	$	—	168.7	$	0.1	$	242.2	$	(159.3)	$	17,377.9	(23.8)	$	(2,977.1)	$	14,483.8	$	(4.1)	$	14,479.7

See accompanying notes to these unaudited condensed consolidated financial statements.

11

BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - (Continued)

(unaudited, in millions)

	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	—	—		—	—		—		—		911.4		—	—		911.4		1.2		912.6
Other comprehensive income (loss), net of tax	—	—		—	—		—		5.6		—		—	—		5.6		—		5.6
Capital contribution from noncontrolling interest	—	—		—	—		—		—		—		—	—		—		4.2		4.2
Issuance of common stock under stock option and stock purchase plans	—	—		0.2	—		38.7		—		—		—	—		38.7		—		38.7
Issuance of common stock under stock award plan	—	—		0.6	—		(86.7)		—		—		—	—		(86.7)		—		(86.7)
Compensation related to share-based payments	—	—		—	—		217.8		—		—		—	—		217.8		—		217.8
Other	—	—		—	—		(0.9)		—		—		—	—		(0.9)		—		(0.9)
Balance, September 30, 2023	—	$	—	168.7	$	0.1	$	242.2	$	(159.3)	$	17,377.9	(23.8)	$	(2,977.1)	$	14,483.8	$	(4.1)	$	14,479.7

See accompanying notes to these unaudited condensed consolidated financial statements.

12

BIOGEN INC. AND SUBSIDIARIES

CONDENSED CONSOLIDATED STATEMENTS OF EQUITY - (Continued)

(unaudited, in millions)

	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, June 30, 2022	—	$	—	169.0	$	0.1	$	—	$	(110.4)	$	14,959.9	(23.8)	$	(2,977.1)	$	11,872.5	$	(9.1)	$	11,863.4
Net income	—	—		—	—		—		—		1,134.7		—	—		1,134.7		0.2		1,134.9
Other comprehensive income (loss), net of tax	—	—		—	—		—		(53.2)		—		—	—		(53.2)		—		(53.2)
Capital contribution from noncontrolling interest	—	—		—	—		—		—		—		—	—		—		0.2		0.2
Repurchase of common stock pursuant to the 2020 Share Repurchase Program, at cost	—	—		—	—		—		—		—		(1.2)	(250.0)		(250.0)		—		(250.0)
Retirement of common stock pursuant to the 2020 Share Repurchase Program, at cost	—	—		(1.2)	—		(71.5)		—		(178.5)		1.2	250.0		—		—		—
Issuance of common stock under stock option and stock purchase plans	—	—		—	—		8.6		—		—		—	—		8.6		—		8.6
Issuance of common stock under stock award plan	—	—		—	—		(2.8)		—		—		—	—		(2.8)		—		(2.8)
Compensation related to share-based payments	—	—		—	—		65.7		—		—		—	—		65.7		—		65.7
Balance, September 30, 2022	—	$	—	167.8	$	0.1	$	—	$	(163.6)	$	15,916.1	(23.8)	$	(2,977.1)	$	12,775.5	$	(8.7)	$	12,766.8

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)

	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, 2021	—	$	—	170.8	$	0.1	$	68.2	$	(106.7)	$	13,911.7	(23.8)	$	(2,977.1)	$	10,896.2	$	63.5	$	10,959.7
Net income	—	—		—	—		—		—		2,496.5		—	—		2,496.5		(84.4)		2,412.1
Other comprehensive income (loss), net of tax	—	—		—	—		—		(56.9)		—		—	—		(56.9)		—		(56.9)
Capital contribution from noncontrolling interest	—	—		—	—		—		—		—		—	—		—		12.2		12.2
Repurchase of common stock pursuant to the 2020 Share Repurchase Program, at cost	—	—		—	—		—		—		—		(3.6)	(750.0)		(750.0)		—		(750.0)
Retirement of common stock pursuant to the 2020 Share Repurchase Program, at cost	—	—		(3.6)	—		(257.9)		—		(492.1)		3.6	750.0		—		—		—
Issuance of common stock under stock option and stock purchase plans	—	—		0.2	—		37.5		—		—		—	—		37.5		—		37.5
Issuance of common stock under stock award plan	—	—		0.4	—		(43.2)		—		—		—	—		(43.2)		—		(43.2)
Compensation related to share-based payments	—	—		—	—		194.1		—		—		—	—		194.1		—		194.1
Other	—	—		—	—		1.3		—		—		—	—		1.3		—		1.3
Balance, September 30, 2022	—	$	—	167.8	$	0.1	$	—	$	(163.6)	$	15,916.1	(23.8)	$	(2,977.1)	$	12,775.5	$	(8.7)	$	12,766.8

See accompanying notes to these unaudited condensed consolidated financial statements.

14

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 and co-developed two treatments to address a defining pathology of Alzheimer's disease. We are focused on advancing our pipeline in neurology, neuropsychiatry, 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; QALSODY for the treatment of ALS, which was granted accelerated approval by the FDA during the second quarter of 2023; ADUHELM for the treatment of Alzheimer's disease; and FUMADERM for the treatment of severe plaque psoriasis. We have collaborations with Eisai on the commercialization of LEQEMBI for the treatment of Alzheimer's disease, which was granted traditional approval by the FDA in the third quarter of 2023, and Sage on the commercialization of ZURZUVAE for the treatment of PPD. ZURZUVAE was approved by the FDA in the third quarter of 2023, pending DEA scheduling, which was completed in the fourth quarter of 2023. 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, which was granted accelerated approval by the FDA during the second quarter of 2023; 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.

On September 26, 2023, we completed the acquisition of Reata. As a result of this transaction we acquired SKYCLARYS, the first and only drug approved by the FDA for the treatment of Friedreich's Ataxia in adults and adolescents aged 16 years and older. For additional information on our acquisition of Reata, please read Note 2, Acquisitions, to these condensed consolidated financial statements.

We commercialize 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. We also have the exclusive rights to commercialize TOFIDENCE, a tocilizumab biosimilar referencing ACTEMRA, which was approved by the FDA during the third quarter of 2023. We continue to develop the 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). For additional information on our collaboration arrangements with Genentech, please read Note 19, Collaborative and Other Relationships, to our audited consolidated financial statements included in our 2022 Form 10-K.

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 2022 Form 10-K. Our accounting policies are described in the Notes to Consolidated Financial Statements in our 2022 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 nine months ended September 30,

15

BIOGEN INC. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

2023, 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.

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.

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 2022 Form 10-K.

Business Combinations

Business combinations are recorded using the acquisition method of accounting. The results of operations of the acquired company are included in our results of operations beginning on the acquisition date, and assets acquired and liabilities assumed are recognized on the acquisition date at their respective fair values. Any excess of consideration transferred over the net carrying value of the assets acquired and liabilities assumed as of the acquisition date is recognized as goodwill. Transaction and restructuring costs related to business combinations are expensed as incurred. The fair value of assets acquired and liabilities assumed in certain cases may be subject to revision based on the final determination of fair value during a period of time not to exceed 12 months from the acquisition date. If we determine the assets acquired do not meet the definition of a business, the transaction will be accounted for as an asset acquisition rather than a business combination.

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.

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BIOGEN INC. AND SUBSIDIARIES

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS

(unaudited, continued)

Fair Value Measurements

In June 2022 the FASB issued ASU No. 2022-03, Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions. This standard clarifies that a contractual restriction on the sale of an equity security is not considered part of the unit of account of the equity security and, therefore, is not considered in measuring fair value. This standard becomes effective for us on January 1, 2024. We elected to early adopt this standard on a prospective basis during the third quarter of 2022. Upon adoption, we recorded an immaterial amount in other (income) expense, net in our condensed consolidated statements of income, as a result of removing the impact of the remaining contractual sale restrictions from the fair value measurement of certain shares in Sage.

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, the first and only drug approved by the FDA 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 three and nine months ended September 30, 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. Approximately $980.0 million of the $983.9 million payment to the equity award holders was made in October 2023.

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.

17

BIOGEN INC. AND SUBSIDIARIES

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 September 26, 2023:

(In millions)	As of September 26, 2023
Cash and cash equivalents	$	267.3
Accounts receivable	15.9
Inventory	1,692.0
Other current assets	53.6
Intangible assets:
Completed technology for SKYCLARYS (U.S.)	3,600.0
In-process research and development (omaveloxolone)	1,900.0
Priority review voucher	100.0
Other clinical programs	20.0
Operating lease assets	122.4
Accrued expense and other	(98.9)
Debt payable	(159.9)
Contingent payable to Blackstone(1)	(300.0)
Deferred tax liability	(922.5)
Operating lease liabilities	(151.8)
Other assets and liabilities, net	(2.0)
Total identifiable net assets	6,136.1
Goodwill	1,057.3
Total assets acquired and liabilities assumed	$	7,193.4

(1) For additional information on the contingent payable to Blackstone, please read Note 18, Other Consolidated Financial Statement Detail, to these condensed consolidated financial statements.

Inventory: Total inventory acquired was approximately $1.7 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 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 $3.6&#