BIIB / Biogen Inc. - SEC फाइलिंग, वार्षिक रिपोर्ट, प्रॉक्सी स्टेटमेंट

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 31, 2025 BIOGEN INC. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 31, 2025 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

Letter regarding employment arrangement of Priya Singhal dated January 3, 2023.

EXHIBIT 10.1 1/3/2023 Priya Singhal [email protected] Dear Priya, I am pleased to offer you a promotion to Executive Vice President (EVP), Head of Drug Development effective January 5th, 2023. This position will report to Biogen’s Chief Executive Officer, Chris Viehbacher. The specific terms of our offer are as follows: Salary: This is a full-time, exempt position and your starting annual s

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission File Number 0-19311 BIOGEN INC. (Exact name of registrant as specified in its

Biogen reports strong second quarter 2025 results and increases full year 2025 guidance

Press Release Cambridge, Mass. – July 31, 2025 Biogen reports strong second quarter 2025 results and increases full year 2025 guidance Second quarter 2025 total revenue $2.6 billion, increased 7% year-over-year; GAAP diluted EPS $4.33, increased 8% year-over-year; Non-GAAP diluted EPS $5.47, increased 4% year-over-year •GAAP and Non-GAAP diluted EPS includes an approximately ($0.26) impact from $4

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 7, 2025 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (IR

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 17, 2025 Biogen Inc. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 17, 2025 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) INFORMATION REQUIRED IN PROXY STATEMENT SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934

DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A (Rule 14a-101) INFORMATION REQUIRED IN PROXY STATEMENT SCHEDULE 14A INFORMATION Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, fo

Underwriting Agreement, dated May 6, 2025, by and among the Company, BofA Securities, Inc., Citigroup Global Markets Inc. and J.P. Morgan Securities LLC, as representatives of the several underwriters named in Schedule I thereto.

EX-1.1 Exhibit 1.1 Execution Version Biogen Inc. 5.050% Senior Notes due 2031 5.750% Senior Notes due 2035 6.450% Senior Notes due 2055 Underwriting Agreement May 6, 2025 BofA Securities, Inc. Citigroup Global Markets Inc. J.P. Morgan Securities LLC As representatives of the several Underwriters named in Schedule I hereto, c/o BofA Securities, Inc.   One Bryant Park   New York, New York 10036-6728

Fourth Supplemental Indenture, dated as of May 12, 2025, between the Company and U.S. Bank Trust Company, National Association (as successor to U.S. Bank, National Association), including the forms of Global Notes attached as Exhibit A, Exhibit B and Exhibit C, respectively, thereto

Exhibit 4.2 BIOGEN INC., as Issuer and U.S. Bank Trust Company, National Association, as Trustee Fourth Supplemental Indenture Dated as of May 12, 2025 TABLE OF CONTENTS Page ARTICLE I DEFINITIONS SECTION 2 Section 1.1. Certain Terms Defined in the Indenture 2 Section 1.2. Definitions 2 ARTICLE II FORM AND TERMS OF THE NOTES 6 Section 2.1. Form and Dating 6 Section 2.2. Terms of the Notes 7 Sectio

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTIONS 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): May 6, 2025 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I.

Calculation of Filing Fee Tables (Form Type) Biogen Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered and Carry Forward Securities

Exhibit 107 Calculation of Filing Fee Tables 424(b)(2) (Form Type) Biogen Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered and Carry Forward Securities Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry Forw

$1,750,000,000 Biogen Inc. $400,000,000 5.050% Senior Notes due 2031 $650,000,000 5.750% Senior Notes due 2035 $700,000,000 6.450% Senior Notes due 2055

Table of Contents Filed pursuant to Rule 424(b)(2) Registration No. 333-286915 Prospectus Supplement (To Prospectus Dated May 1, 2025) $1,750,000,000 Biogen Inc. $400,000,000 5.050% Senior Notes due 2031 $650,000,000 5.750% Senior Notes due 2035 $700,000,000 6.450% Senior Notes due 2055 We are offering $400,000,000 aggregate principal amount of our 5.050% Senior Notes due 2031 (the “notes due 2031

Subject to completion, dated May 6, 2025

Table of Contents Filed pursuant to Rule 424(b)(2) Registration No. 333-286915 The information in this preliminary prospectus supplement and the accompanying prospectus is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities and we are not soliciting an offer to buy these securities in any jurisdiction whe

$1,750,000,000 Biogen Inc. $400,000,000 5.050% Senior Notes Due 2031 $650,000,000 5.750% Senior Notes Due 2035 $700,000,000 6.450% Senior Notes Due 2055 PRICING TERM SHEET $400,000,000 5.050% Senior Notes Due 2031 Issuer Biogen Inc. Principal Amount

Filed pursuant to Rule 433 Registration No.: 333-286915 Free Writing Prospectus dated May 6, 2025 Relating to Preliminary Prospectus Supplement dated May 6, 2025 (to Prospectus dated May 1, 2025) $1,750,000,000 Biogen Inc. $400,000,000 5.050% Senior Notes Due 2031 $650,000,000 5.750% Senior Notes Due 2035 $700,000,000 6.450% Senior Notes Due 2055 PRICING TERM SHEET $400,000,000 5.050% Senior Notes

Powers of Attorney of Biogen Inc. (included on signature pages to this Registration Statement)**

As filed with the Securities and Exchange Commission on May 1, 2025 No. 333-    UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-3 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 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 N

Filing Fee Table**

Exhibit 107 Calculation of Filing Fee Tables FORM S-3 (Form Type) Biogen Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered and Carry Forward Securities Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered (2) Proposed  Maximum  Offering  Price Per  Unit (2)  Maximum  Aggregate  Offering  Price (2)  Fee Rate Amount of Registr

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 1, 2025 BIOGEN INC. (Exact na

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 1, 2025 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (IRS

Form 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended March 31, 2025 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission File Number 0-19311 BIOGEN INC. (Exact name of registrant as specified in its

Form T-1 Statement of Eligibility of Trustee under the Trust Indenture Act of 1939, as amended, of U.S. Bank Trust Company, National Association (as successor-in-interest to U.S. Bank National Association), as trustee**

EX-25.1 Exhibit 25.1 SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE ☐ Check if an Application to Determine Eligibility of a Trustee Pursuant to Section 305(b)(2) U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION (Exact name of Trustee as specified in its charter) 91-1821036

Biogen reports strong first quarter 2025 results

Press Release Cambridge, Mass. – May 1, 2025 Biogen reports strong first quarter 2025 results First quarter 2025 total revenue $2.4 billion, increased 6% year-over-year; GAAP diluted EPS $1.64; Non-GAAP diluted EPS $3.02 •Product revenue increased 3% at constant currency and 1% at actual currency year-over-year, aided in part by the timing of SPINRAZA shipments •GAAP and Non-GAAP diluted EPS inclu

Your Vote Counts! BIOGEN INC. 2025 Annual Meeting Vote by June 16, 2025 11:59 PM ET BIOGEN INC. 225 BINNEY STREET CAMBRIDGE, MA 02142 V69530-P28515 You invested in BIOGEN INC. and it’s time to vote! You have the right to vote on proposals being prese

DEFA14A Your Vote Counts! BIOGEN INC. 2025 Annual Meeting Vote by June 16, 2025 11:59 PM ET BIOGEN INC. 225 BINNEY STREET CAMBRIDGE, MA 02142 V69530-P28515 You invested in BIOGEN INC. and it’s time to vote! You have the right to vote on proposals being presented at the Annual Meeting. This is an important notice regarding the availability of proxy materials for the stockholder meeting to be held o

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒     Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☒

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 12, 2025 BIOGEN INC. (Ex

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 12, 2025 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number

Voluntary Board of Directors Savings Plan.

EXHIBIT 10.14 BIOGEN INC. VOLUNTARY BOARD OF DIRECTORS SAVINGS PLAN (Plan Provisions as in Effect on January 1, 2024) TABLE OF CONTENTS ARTICLE 1 DEFINITIONS...........................................................................................................1 1.1 Purpose and Effective Date..............................................................................................1 ARTICLE

Biogen reports fourth quarter and full year 2024 results and provides full year 2025 financial guidance

Press Release Cambridge, Mass. – Feb. 12, 2025 Biogen reports fourth quarter and full year 2024 results and provides full year 2025 financial guidance Fourth quarter 2024 total revenue $2.5 billion, 3% growth YoY; GAAP diluted EPS $1.83, 7% growth YoY; Non-GAAP diluted EPS $3.44, 17% growth YoY Full year 2024 total revenue $9.7 billion, 2% decline YoY; GAAP diluted EPS $11.18, 40% growth YoY; Non-

Biogen Inc. Supplemental Savings Plan.

EXHIBIT 10.15 BIOGEN INC. SUPPLEMENTAL SAVINGS PLAN (Plan Provisions as in Effect on January 1, 2024) TABLE OF CONTENTS Page ARTICLE 1 INTRODUCTION 1 1.1 Purpose and Effective Date 1 ARTICLE 2 DEFINITIONS 1 2.1 401(k) restoration 1 2.2 Applicable compensation 1 2.3 Base salary 1 2.4 Biogen 1 2.5 Biogen SERP 2 2.6 Board 2 2.7 Change in Control 2 2.8 Code 2 2.9 Committee 2 2.10 Compensation Committe

BIOGEN INC.

Exhibit 21 BIOGEN INC. The following is a list of subsidiaries of Biogen Inc. as of December 31, 2024, omitting some subsidiaries which, considered in the aggregate, would not constitute a significant subsidiary. SUBSIDIARY STATE OR OTHER JURISDICTION OF INCORPORATION OR ORGANIZATION Biogen Foundation Inc. Massachusetts Biogen MA Inc. Massachusetts Biogen Realty Corporation Massachusetts Biogen Re

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 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 cha

Policy relating to insider trading.

Exhibit 19.1 Global Insider Trading and Information Policy Purpose 1.1Introduction. U.S. federal and state securities laws prohibit the purchase or sale of a company’s securities by persons who possess Material, Nonpublic Information. These laws also prohibit persons from making Selective Disclosure. Many countries in addition to the U.S. also have laws prohibiting Insider Trading. 1.2Purpose. The

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 13, 2025 Biogen Inc. (Exa

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 13, 2025 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

DNLI / Denali Therapeutics Inc. / BIOGEN INC. - SC 13G/A Passive Investment

SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* DENALI THERAPEUTICS INC. (Name of Issuer) Common Stock, $0.01 par value (Title of Class of Securities) 24823R105 (CUSIP Number) October 30, 2024 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the r

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 30, 2024 BIOGEN INC. (Exa

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 30, 2024 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

Biogen reports third quarter 2024 results and raises full year 2024 financial guidance

Press Release Cambridge, Mass. – October 30, 2024 Biogen reports third quarter 2024 results and raises full year 2024 financial guidance Third quarter 2024 revenue $2.5 billion; GAAP diluted EPS $2.66; Non-GAAP diluted EPS $4.08 Continued progress executing across the commercial portfolio •Product launches in Alzheimer's disease, rare disease, and depression each delivered sequential revenue growt

Regulation FD Disclosure

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 28, 2024 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

Michael McDonnell, Executive Vice President and Chief Financial Officer to Retire in February 2025 Robin Kramer, Chief Accounting Officer, to Succeed Him

Exhibit 99.1 Michael McDonnell, Executive Vice President and Chief Financial Officer to Retire in February 2025 Robin Kramer, Chief Accounting Officer, to Succeed Him CAMBRIDGE, Mass., Oct. 28, 2024 (GLOBE NEWSWIRE) – Biogen Inc. (Nasdaq: BIIB) today announced that Michael McDonnell, Biogen’s Executive Vice President and Chief Financial Officer, plans to retire from the company on February 28, 202

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

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, 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

Letter regarding employment arrangement of Robin Kramer dated October 28, 2024

Exhibit 10.1 10/28/2024 Robin Kramer [ ] Dear Robin, I am pleased to offer you a promotion to Executive Vice President (EVP), Chief Financial Officer effective February 28, 2025. This position will report to Biogen’s Chief Executive Officer, Chris Viehbacher. The specific terms of our offer are as follows: Salary: This is a full-time, exempt position and your starting annual salary will be $750,00

BIIB / Biogen Inc. / STATE STREET CORP Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. )* BIOGEN INC (Name of Issuer) COMMON STOCK (Title of Class of Securities) 09062X103 (CUSIP Number) September 30, 2024 (Date of Event Which Requires Filing of This Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is filed: ý Rule

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 11, 2024 Biogen Inc. (E

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 11, 2024 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Numbe

SGMO / Sangamo Therapeutics, Inc. / BIOGEN INC. - SC 13G/A Passive Investment

SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 2)* SANGAMO THERAPEUTICS, INC. (Name of Issuer) Common Stock, $0.01 par value (Title of Class of Securities) 800677106 (CUSIP Number) August 14, 2024 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 12, 2024 Biogen Inc. (Exac

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 12, 2024 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

Credit Agreement, dated as of August 12, 2024, among Biogen Inc., Bank of America, N.A., as administrative agent, swing line lender and the L/C issuer, and the other lenders party thereto

Exhibit 10.1 EXECUTION VERSION CUSIP Numbers: Deal: 09074KAH0 Revolver: 09074KAJ6 CREDIT AGREEMENT Dated as of August 12, 2024 among BIOGEN INC., as the Borrower, BANK OF AMERICA, N.A., as the Administrative Agent, the Swing Line Lender and the L/C Issuer, CITIBANK, N.A., DEUTSCHE BANK SECURITIES INC., GOLDMAN SACHS BANK USA, JPMORGAN CHASE BANK, N.A., MIZUHO BANK, LTD., MORGAN STANLEY SENIOR FUND

Form of restricted stock unit award agreement for non-employee Director's under the Biogen Inc. 2024 Omnibus Equity Plan.

Exhibit 10.5 NON-EMPLOYEE DIRECTOR RESTRICTED STOCK UNIT AWARD AGREEMENT GRANTED UNDER BIOGEN INC. 2024 OMNIBUS EQUITY PLAN 1.Grant of Restricted Stock Units Pursuant to the Biogen Inc. 2024 Omnibus Equity Plan (as it may be amended from time to time, the “Plan”), Biogen Inc. (the “Company”) hereby grants to you, a non-employee director of the Company or one of its Affiliates (the “Participant”),

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 1, 2024 BIOGEN INC. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): August 1, 2024 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (

Form of restricted stock award agreement under the Biogen Inc. 2024 Omnibus Equity Plan. Filed as Exhibit 10.4 to our Quarterly Report on Form 10-Q for the quarter ended June 30, 2024.

Exhibit 10.4 RESTRICTED STOCK UNIT AWARD AGREEMENT GRANTED UNDER BIOGEN INC. 2024 OMNIBUS EQUITY PLAN 1.Grant of Restricted Stock Units Pursuant to the Biogen Inc. 2024 Omnibus Equity Plan (as it may be amended from time to time, the “Plan”), Biogen Inc. (the “Company”) hereby grants to you, an employee or service provider of the Company or one of its Affiliates (the “Participant”), on each of the

Form of performance share award agreement under the Biogen Inc. 2024 Omnibus Equity Plan.

Exhibit 10.3 PERFORMANCE STOCK UNITS AWARD AGREEMENT GRANTED UNDER BIOGEN INC. 2024 OMNIBUS EQUITY PLAN 1.Grant of Performance Stock Units Pursuant to the Biogen Inc. 2024 Omnibus Equity Plan (as it may be amended from time to time, the “Plan”), Biogen Inc. (the “Company”) hereby grants to you, an employee or service provider of the Company or one of its Affiliates (the “Participant”), on each of

Biogen reports strong second quarter 2024 results and raises full year 2024 financial guidance; Second quarter 2024 total revenue of $2.5 billion, GAAP diluted EPS of $4.00 and Non-GAAP diluted EPS of $5.28

EX-99.1 2 exhibit991-q22024pressrele.htm EX-99.1 Press Release Cambridge, Mass. – Aug. 1, 2024 Biogen reports strong second quarter 2024 results and raises full year 2024 financial guidance; Second quarter 2024 total revenue of $2.5 billion, GAAP diluted EPS of $4.00 and Non-GAAP diluted EPS of $5.28 Second quarter total revenue was flat at actual currency and up 1% at constant currency, with GAAP

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 20, 2024 Biogen Inc. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 20, 2024 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

Certificate of Amendment of Biogen Inc.’s Amended and Restated Certificate of Incorporation, as amended.

Exhibit 3.1 CERTIFICATE OF AMENDMENT TO THE CERTIFICATE OF INCORPORATION OF BIOGEN INC. Pursuant to Section 242 of the General Corporation Law of the State of Delaware Biogen Inc. (hereinafter referred to as the “Corporation”), a corporation duly organized and existing under the Delaware General Corporation Law (the “DGCL”), does hereby certify as follows: FIRST: That resolutions were duly adopted

Certificate of Amendment of Biogen Inc.’s Amended and Restated Certificate of Incorporation, as amended.

Exhibit 4.4 CERTIFICATE OF AMENDMENT TO THE CERTIFICATE OF INCORPORATION OF BIOGEN INC. Pursuant to Section 242 of the General Corporation Law of the State of Delaware Biogen Inc. (hereinafter referred to as the “Corporation”), a corporation duly organized and existing under the Delaware General Corporation Law (the “DGCL”), does hereby certify as follows: FIRST: That resolutions were duly adopted

As filed with the Securities and Exchange Commission on June 20, 2024

As filed with the Securities and Exchange Commission on June 20, 2024 Registration No.

Filing Fee Table.

Exhibit 107 Filing Fee Table Form S-8 (Form Type) Biogen Inc. (Exact Name of Registrant as Specified in its Charter) Table 1: Newly Registered Securities Security Type Security Class Title Fee Calculation Rule Amount Registered(1) Proposed Maximum Offering Price Per Share Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Equity Common stock, par value $0.0005 per share, reserved

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒     Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☒

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 1)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 1) Filed by the Registrant ☒      Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 24, 2024 BIOGEN INC. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 24, 2024 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (

Biogen reports first quarter 2024 GAAP EPS growth of 1% and Non-GAAP EPS growth of 8%

Press Release Cambridge, Mass. – Apr. 24, 2024 Biogen reports first quarter 2024 GAAP EPS growth of 1% and Non-GAAP EPS growth of 8% First quarter revenue $2.3 billion; GAAP diluted EPS $2.70; Non-GAAP diluted EPS $3.67 First quarter product revenue decreased 3% and total revenue decreased 7%, while GAAP operating income grew 10% and Non-GAAP operating income grew 24%; meaningful improvement in bo

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒     Filed by a Party other than the Registrant ☐ Check the appropriate box: ☒ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐

Description of Securities.

Exhibit 4.6 DESCRIPTION OF THE REGISTRANT’S SECURITIES REGISTERED PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934 As of December 31, 2023, Biogen Inc. (the “Company”) has one class of securities registered under Section 12 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”): our Common Stock. Description of Common Stock The following description of our Common Stoc

etter regarding employment arrangement of Rachid Izzar dated August

July 29, 2019 Dear Rachid, I am pleased to extend you this offer of employment to join Biogen with the job title of President, Intercontinental.

Filed as Exhibit 97.1 to our Annual Report on Form 10-K for the year ended December 31, 2023.

FINAL BIOGEN INC. POLICY FOR RECOUPMENT OF INCENTIVE COMPENSATION 1.Introduction In accordance with Section 10D of the Securities Exchange Act of 1934, as amended (the Exchange Act”), and the regulations promulgated thereunder, the Board of Directors (the “Board”) of Biogen Inc.(the “Company”) has adopted a policy (the “Policy”) providing for the Company’s recoupment of certain incentive-based com

BIOGEN INC.

Exhibit 21 BIOGEN INC. The following is a list of subsidiaries of Biogen Inc. as of December 31, 2023, omitting some subsidiaries which, considered in the aggregate, would not constitute a significant subsidiary. SUBSIDIARY STATE OR OTHER JURISDICTION OF INCORPORATION OR ORGANIZATION Biogen Foundation Inc. Massachusetts Biogen MA Inc. Massachusetts Biogen Realty Corporation Massachusetts Biogen Re

Letter amending employment arrangement of Susan Alexander dated February 28, 2020.

February 28, 2020 VIA ELECTRONIC DELIVERY Susan Alexander [*] Dear Susan: Reference is made to your offer letter dated December 13, 2005 (“Offer Letter”), between you and Biogen Idec (now Biogen Inc.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 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 cha

, Samsung BioLogics Co., Ltd. and Samsung Bioepis Co., Ltd, dated April 20, 2020.

Execution Version JVA TERMINATION AGREEMENT THIS JVA TERMINATION AGREEMENT (this “Agreement”) is entered into this 20th day of April, 2022, by and between: (1)Biogen Therapeutics Inc.

Biogen reports fourth quarter and full year 2023 results and expects return to Non-GAAP EPS growth in 2024

Press Release Cambridge, Mass. – Feb. 13, 2024 Biogen reports fourth quarter and full year 2023 results and expects return to Non-GAAP EPS growth in 2024 Fourth quarter 2023 revenue $2.4 billion; GAAP diluted EPS $1.71; Non-GAAP diluted EPS $2.95 •GAAP and Non-GAAP diluted EPS negatively impacted by $0.35 related to previously disclosed closeout costs for ADUHELM Full year 2023 revenue $9.8 billio

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 13, 2024 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number

BIIB / Biogen Inc. / PRIMECAP MANAGEMENT CO/CA/ - PRIMECAP MANAGEMENT CO/CA/ Passive Investment

SC 13G/A 1 biiba2621224.htm PRIMECAP MANAGEMENT CO/CA/ UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 26)* Biogen Inc. (Name of Issuer) COM (Title of Class of Securities) 09062X103 (CUSIP Number) December 31, 2023 (Date of Event which Requires Filing of this Statement) Check the appropriate box to design

DNLI / Denali Therapeutics Inc. / BIOGEN INC. - SC 13G/A Passive Investment

SC 13G/A 1 d589107dsc13ga.htm SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* DENALI THERAPEUTICS INC. (Name of Issuer) Common Stock, $0.01 par value (Title of Class of Securities) 24823R105 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of this Statement) Check the app

BIIB / Biogen Inc. / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SC 13G/A 1 tv0011-biogeninc.htm SCHEDULE 13G/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 10)* Name of issuer: Biogen Inc Title of Class of Securities: Common Stock CUSIP Number: 09062X103 Date of Event Which Requires Filing of this Statement: January 31, 2024 Check the appropriate box to designate the rule pursu

SGMO / Sangamo Therapeutics, Inc. / BIOGEN INC. - SC 13G/A Passive Investment

SC 13G/A 1 d662582dsc13ga.htm SC 13G/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* SANGAMO THERAPEUTICS, INC. (Name of Issuer) Common Stock, $0.01 par value (Title of Class of Securities) 800677106 (CUSIP Number) December 31, 2023 (Date of Event Which Requires Filing of this Statement) Check the a

BIIB / Biogen Inc. / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 9)* Name of issuer: Biogen Inc Title of Class of Securities: Common Stock CUSIP Number: 09062X103 Date of Event Which Requires Filing of this Statement: December 29, 2023 Check the appropriate box to designate the rule pursuant to which this Schedule is filed: ☒ Rule 13d

Fifth Amended and Restated Bylaws. Filed as Exhibit 3.1 to our Current Report on Form 8-K filed on December 12, 2023.

Exhibit 3.1 FIFTH AMENDED AND RESTATED BYLAWS OF BIOGEN INC. TABLE OF CONTENTS Page ARTICLE 1 Offices 1 1.1 Registered Office 1 1.2 Other Offices 1 ARTICLE 2 Meeting of Stockholders 1 2.1 Place of Meeting 1 2.2 Annual Meeting 1 2.3 Special Meetings Called by Directors or Officers 4 2.3A Special Meetings Called by Stockholders 4 2.4 Notice of Meetings 7 2.5 List of Stockholders 8 2.6 Organization a

Marked Fifth Amended and Restated Bylaws of Biogen Inc.

Exhibit 3.2 FOURTHFIFTH AMENDED AND RESTATED BYLAWS OF BIOGEN INC. TABLE OF CONTENTS Page ARTICLE 1 Offices 1 1.1 Registered Office 1 1.2 Other Offices 1 ARTICLE 2 Meeting of Stockholders 1 2.1 Place of Meeting 1 2.2 Annual Meeting 1 2.3 Special Meetings Called by Directors or Officers 4 2.3A Special Meetings Called by Stockholders 5 2.4 Notice of Meetings 68 2.5 List of Stockholders 78 2.6 Organi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 6, 2023 Biogen Inc. (Exa

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): December 6, 2023 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 8, 2023 BIOGEN INC. (Exa

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 8, 2023 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

Biogen reports third quarter 2023 results and updates full year 2023 guidance

Press Release Cambridge, Mass. – Nov. 8, 2023 Biogen reports third quarter 2023 results and updates full year 2023 guidance Third quarter revenue $2,530 million; GAAP diluted EPS $(0.47); Non-GAAP diluted EPS $4.36 Poised for leadership in Alzheimer's disease with ongoing LEQEMBI launch and development of tau-directed ASO (BIIB080) •New data support potential for subcutaneous formulation of LEQEMB

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 6, 2023 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 26, 2023 Biogen Inc. (Exac

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 26, 2023 Biogen Inc. (Exact name of Registrant as specified in its charter) Delaware 0-19311 33-0112644 (State of Incorporation) (Commission File Number) (I.R.S. Employer Ident

RETA / Reata Pharmaceuticals Inc - Class A / BIOGEN INC. - SC 13D/A Activist Investment

SC 13D/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D/A (Amendment No. 1)* Under the Securities Exchange Act of 1934 REATA PHARMACEUTICALS, INC. (Name of Issuer) Class A Common Stock, par value $0.001 per share (Title of Class of Securities) 75615P 103 (CUSIP Number) Biogen Inc. 225 Binney Street Cambridge, Massachusetts 02142 (617) 679-2000 Attention: Wende

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): September 26, 2023 BIOGEN INC. (

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): September 26, 2023 BIOGEN INC. (Exact Name of Registrant as Specified in Charter) Delaware 0-19311 33-0112644 (State or Other Jurisdiction of Incorporation) (Commission File Number)

Biogen Completes Acquisition of Reata Pharmaceuticals

EX-99.1 Exhibit 99.1 Biogen Completes Acquisition of Reata Pharmaceuticals • Reata acquisition bolsters Biogen’s rare disease portfolio with the addition of SKYCLARYS® (omaveloxolone), the first and only FDA approved treatment for Friedreich’s ataxia in the U.S. CAMBRIDGE, Mass., Sept. 26, 2023 (GLOBE NEWSWIRE) – Biogen Inc. (Nasdaq: BIIB) – has completed the acquisition of Reata Pharmaceuticals,

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 28, 2023 BIOGEN INC. (Exa

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): August 28, 2023 BIOGEN INC. (Exact Name of Registrant as Specified in Charter) Delaware 0-19311 33-0112644 (State or Other Jurisdiction of Incorporation) (Commission File Number) (IR

Credit Agreement, dated as of August 28, 2023, among Biogen Inc., JPMorgan Chase Bank N.S., as administrative agent and the other lenders party thereto. Filed as Exhibit 10.1 to our Current Report on Form 8-K filed on September 1, 2023.

Exhibit 10.1 EXECUTION VERSION TERM LOAN CREDIT AGREEMENT Dated as of August 28, 2023 among BIOGEN INC., as the Borrower, JPMORGAN CHASE BANK, N.A., as Administrative Agent and The Other Lenders Party Hereto JPMORGAN CHASE BANK, N.A., BANK OF AMERICA, N.A., BANK OF CHINA, NEW YORK BRANCH, CITIBANK, N.A., DEUTSCHE BANK SECURITIES INC., MIZUHO BANK, LTD., MORGAN STANLEY SENIOR FUNDING, INC., U.S. BA

RETA / Reata Pharmaceuticals Inc - Class A / BIOGEN INC. - SC 13D Activist Investment

SC 13D UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 REATA PHARMACEUTICALS, INC. (Name of Issuer) Class A Common Stock, par value $0.001 per share (Title of Class of Securities) 75615P 103 (CUSIP Number) Biogen Inc. 225 Binney Street Cambridge, Massachusetts 02142 (617) 679-2000 Attention: Wendell Taylor, Assistant Se

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): July 28, 2023 BIOGEN INC. (Exact

DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): July 28, 2023 BIOGEN INC. (Exact Name of Registrant as Specified in Charter) Delaware 0-19311 33-0112644 (State or Other Jurisdiction of Incorporation) (Commission File Numbe

Voting and Support Agreement, dated as of July 28, 2023, by and among Biogen Inc., River Acquisition, Inc. and each stockholder of Reata Pharmaceuticals, Inc., set forth on Exhibit A thereto

EX-10.1 Exhibit 10.1 Execution Version VOTING AND SUPPORT AGREEMENT THIS VOTING AND SUPPORT AGREEMENT is dated as of July 28, 2023 (this “Agreement”), by and among each stockholder of Reata Pharmaceuticals, Inc., a Delaware corporation (the “Company”), set forth on Exhibit A hereto (each a “Holder” and collectively the “Holders”), Biogen Inc., a Delaware corporation (“Parent”), and River Acquisiti

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): July 28, 2023 BIOGEN INC. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): July 28, 2023 BIOGEN INC. (Exact Name of Registrant as Specified in Charter) Delaware 0-19311 33-0112644 (State or Other Jurisdiction of Incorporation) (Commission File Number) (IRS

Agreement and Plan of Merger by and among Reata Pharmaceuticals, Inc., Biogen Inc. and River Acquisition, Inc. dated as of July 28, 2023. Filed as Exhibit 2.1 to our current report on Form 8-K filed July 31, 2023.

EX-2.1 Exhibit 2.1 Execution Version AGREEMENT AND PLAN OF MERGER by and among REATA PHARMACEUTICALS, INC., BIOGEN INC. and RIVER ACQUISITION, INC. Dated as of July 28, 2023 TABLE OF CONTENTS Page ARTICLE I DEFINITIONS & INTERPRETATIONS 1.1 Certain Definitions 2 1.2 Additional Definitions 13 1.3 Certain Interpretations 15 ARTICLE II THE MERGER 2.1 The Merger 16 2.2 The Effective Time 16 2.3 The Cl

Fourth Amended and Restated Bylaws of Biogen Inc.

Exhibit 3.1 FOURTH AMENDED AND RESTATED BYLAWS OF BIOGEN INC. TABLE OF CONTENTS Page ARTICLE 1 Offices 1 1.1 Registered Office 1 1.2 Other Offices 1 ARTICLE 2 Meeting of Stockholders 1 2.1 Place of Meeting 1 2.2 Annual Meeting 1 2.3 Special Meetings Called by Directors or Officers 4 2.3A Special Meetings Called by Stockholders 4 2.4 Notice of Meetings 6 2.5 List of Stockholders 7 2.6 Organization

Voting and Support Agreement, dated as of July 28, 2023, by and among Biogen Inc., River Acquisition, Inc. and each stockholder of Reata Pharmaceuticals, Inc., set forth on Exhibit A thereto

EX-10.3 Exhibit 10.3 Execution Version VOTING AND SUPPORT AGREEMENT THIS VOTING AND SUPPORT AGREEMENT is dated as of July 28, 2023 (this “Agreement”), by and among each stockholder of Reata Pharmaceuticals, Inc., a Delaware corporation (the “Company”), set forth on Exhibit A hereto (each a “Holder” and collectively the “Holders”), Biogen Inc., a Delaware corporation (“Parent”), and River Acquisiti

Voting and Support Agreement, dated as of July 28, 2023, by and among Biogen Inc., River Acquisition, Inc. and each stockholder of Reata Pharmaceuticals, Inc., set forth on Exhibit A thereto

EX-10.2 Exhibit 10.2 Execution Version VOTING AND SUPPORT AGREEMENT THIS VOTING AND SUPPORT AGREEMENT is dated as of July 28, 2023 (this “Agreement”), by and among each stockholder of Reata Pharmaceuticals, Inc., a Delaware corporation (the “Company”), set forth on Exhibit A hereto (each a “Holder” and collectively the “Holders”), Biogen Inc., a Delaware corporation (“Parent”), and River Acquisiti

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): July 28, 2023 BIOGEN INC. (Exact

DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): July 28, 2023 BIOGEN INC. (Exact Name of Registrant as Specified in Charter) Delaware 0-19311 33-0112644 (State or Other Jurisdiction of Incorporation) (Commission File Numbe

Biogen to Acquire Reata Pharmaceuticals SKYCLARYS® recently approved in US as the only treatment indicated for patients with Friedreich’s ataxia Proposed acquisition represents meaningful step forward in Biogen’s strategy for sustainable growth, addi

Exhibit 99.1 CONFIDENTIAL PLANNING MATERIALS NOT FOR EXTERNAL DISTRIBUTION DRAFT SUBJECT TO FURTHER REVIEW July 28, 2023 Project River: Announcement Press Release Biogen to Acquire Reata Pharmaceuticals SKYCLARYS® recently approved in US as the only treatment indicated for patients with Friedreich’s ataxia Proposed acquisition represents meaningful step forward in Biogen’s strategy for sustainable

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15 (d) of The Securities Exchange Act of 1934 Date of report (Date of earliest event reported): July 28, 2023 BIOGEN INC. (Exact Name of Registrant as Specified in Charter) Delaware 0-19311 33-0112644 (State or Other Jurisdiction of Incorporation) (Commission File Number) (IRS

Forward-looking statements This presentation contains forward-looking statements, relating to: our strategy and plans; potential of, and expectations for, our commercial business and pipeline programs; capital allocation and investment strategy; clin

EX-99.2 Exhibit 99.2 Proposed Acquisition of Reata Pharmaceuticals, Inc. Investor Webcast July 28, 2023 Forward-looking statements This presentation contains forward-looking statements, relating to: our strategy and plans; potential of, and expectations for, our commercial business and pipeline programs; capital allocation and investment strategy; clinical development programs, clinical trials, an

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 25, 2023 BIOGEN INC. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 25, 2023 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 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

Biogen reports second quarter 2023 results and reaffirms full year 2023 guidance; LEQEMBI launched in the U.S.

Press Release Cambridge, Mass. – July 25, 2023 Biogen reports second quarter 2023 results and reaffirms full year 2023 guidance; LEQEMBI launched in the U.S. Second quarter revenue $2,456 million; GAAP diluted EPS $4.07; Non-GAAP diluted EPS $4.02 Poised for leadership in Alzheimer's disease with launch of LEQEMBI in the U.S. New "Fit for Growth" program expected to generate approximately $1 billi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 26, 2023 Biogen Inc. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 26, 2023 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 1)

DEFR14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 1) Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Pro

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Pro

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 3, 2023 Biogen Inc. (Exact na

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 3, 2023 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (IRS

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

DEFA14A Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☒ Defi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 25, 2023 BIOGEN INC. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 25, 2023 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

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, 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

Strong progress toward three potential launches in 2023; Company reports first quarter 2023 results and reaffirms full year 2023 guidance

Strong progress toward three potential launches in 2023; Company reports first quarter 2023 results and reaffirms full year 2023 guidance First quarter 2023 financial results •First quarter revenue $2,463 million; GAAP diluted EPS $2.

Letter regarding employment arrangement of Ginger Gregory dated June 9, 2017.

Exhibit 10.2 CERTAIN INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY [***], HAS BEEN OMITTED BECAUSE IT IS BOTH NOT MATERIAL AND IS THE TYPE THAT BIOGEN INC. TREATS AS PRIVATE OR CONFIDENTIAL. June 9, 2017 Ginger Gregory [***] Dear Ginger, I am pleased to extend you this offer of employment to join Biogen with the job title of EVP, Chief Human Resources Officer. This position will report to Mich

etter regarding employment arrangement of Nicole Murphy dated January 28, 2022. Filed as Exhi

Exhibit 10.3 1/28/2022 Nicole Murphy [email protected] Dear Nicole, I am pleased to offer you a promotion to Executive Vice President (EVP), Head of Pharmaceutical Operations & Technology effective February 1, 2022. This position will report to Biogen's Chief Executive Officer, Michel Vounatsos. The effective date of this new position will be arranged following your formal acceptance of thi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 12, 2023 Biogen Inc. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 12, 2023 Biogen Inc. (Exact name of Registrant as specified in its charter) Delaware 0-19311 33-0112644 (State of Incorporation) (Commission File Number) (I.R.S. Employer Identi

Fourth Amended and Restated Bylaws of Biogen Inc.

EX-3.1 Exhibit 3.1 FOURTH AMENDED AND RESTATED BYLAWS OF BIOGEN INC. TABLE OF CONTENTS Page ARTICLE 1 Offices 1 1.1 Registered Office 1 1.2 Other Offices 1 ARTICLE 2 Meeting of Stockholders 1 2.1 Place of Meeting 1 2.2 Annual Meeting 1 2.3 Special Meetings Called by Directors or Officers 4 2.3A Special Meetings Called by Stockholders 4 2.4 Notice of Meetings 6 2.5 List of Stockholders 7 2.6 Organi

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 5, 2023 Biogen Inc. (Exact

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): March 5, 2023 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

Amended and Restated Collaboration Agreement, dated October 22, 2017, between Biogen MA Inc. and Eisai Co., LTD. Filed as Exhibit 10.45 to our Annual Report on Form 10-K for the year ended December 31, 2022.

EXHIBIT 10.45 CERTAIN INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY [***], HAS BEEN OMITTED BECAUSE IT IS BOTH NOT MATERIAL AND IS THE TYPE THAT BIOGEN INC. TREATS AS PRIVATE OR CONFIDENTIAL. Execution Version AMENDED AND RESTATED COLLABORATION AGREEMENT dated as of October 22, 2017 between BIOGEN MA INC. and EISAI CO., LTD. 1325396161 TABLE OF CONTENTS Page ARTICLE 1 DEFINITIONS 1 ARTICLE 2 C

Amendment to Credit Agreement, dated as of February 7, 2023, by and among Biogen Inc., Bank of America, N.A., as administrative agent, swing line lender and the L&C issuer, and the other lenders party thereto.

EXHIBIT 10.3 EXECUTION VERSION AMENDMENT TO CREDIT AGREEMENT THIS AMENDMENT TO CREDIT AGREEMENT (this “Agreement”), dated as of February 7, 2023 (the “Amendment Effective Date”), is entered into among BIOGEN INC., a Delaware corporation (the “Borrower”), each Lender party hereto, and BANK OF AMERICA, N.A., as the Administrative Agent, the Swing Line Lender, and the L/C Issuer. All capitalized term

First Amendment to Amended and Restated Collaboration Agreement, dated March 13, 2022, between Biogen MA Inc. and Eisai Co., LTD. Filed as Exhibit 10.46 to our Annual Report on Form 10-K for the year ended December 31, 2022.

EXHIBIT 10.46 FIRST AMENDMENT TO AMENDED AND RESTATED COLLABORATION AGREEMENT This First Amendment to the Amended and Restated Collaboration Agreement (this “Amendment”) is entered into as of March 13, 2022 (the “Amendment Effective Date”), by and between Eisai Co., Ltd., a Japanese corporation, with a place of business at 4-6-10, Koishikawa, Bunkyo-ku Tokyo 112-8088, Japan (“Eisai”) and Biogen MA

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 15, 2023 BIOGEN INC. (Ex

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 15, 2023 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 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 cha

BIOGEN INC.

Exhibit 21 BIOGEN INC. The following is a list of subsidiaries of Biogen Inc. as of December 31, 2022, omitting some subsidiaries which, considered in the aggregate, would not constitute a significant subsidiary. SUBSIDIARY STATE OR OTHER JURISDICTION OF INCORPORATION OR ORGANIZATION Biogen Foundation Inc. Massachusetts Biogen MA Inc. Massachusetts Biogen Realty Corporation Massachusetts Biogen Re

Form of nonqualified stock option award agreement under Biogen Inc. 2017 Omnibus Equity Plan. Filed as Exhibit 10.20 to our Annual Report on Form 10-K for the year ended December 31, 2022.

EXHIBIT 10.20 NONQUALIFIED STOCK OPTION AWARD AGREEMENT GRANTED UNDER BIOGEN INC. 2017 OMNIBUS EQUITY PLAN 1.Grant of Options Pursuant to the Biogen Inc. 2017 Omnibus Equity Plan (as it may be amended, modified, or supplemented from time to time, the “Plan”), Biogen Inc. (the “Company") hereby grants an employee of the Company or its Affiliates (the “Participant”), on (the “Grant Date”), a nonqual

Biogen advances significant potential growth drivers; Company reports full year 2022 results and provides full year 2023 guidance

Biogen advances significant potential growth drivers; Company reports full year 2022 results and provides full year 2023 guidance Full year 2022 revenue and Non-GAAP EPS exceed guidance •Fourth quarter revenue $2,544 million; GAAP diluted EPS $3.

BIIB / Biogen Inc / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SC 13G/A 1 tv0413-biogeninc.htm SCHEDULE 13G/A SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 8)* Name of issuer: Biogen Inc. Title of Class of Securities: Common Stock CUSIP Number: 09062X103 Date of Event Which Requires Filing of this Statement: December 30, 2022 Check the appropriate box to designate the rule purs

BIIB / Biogen Inc / PRIMECAP MANAGEMENT CO/CA/ - PRIMECAP MANAGEMENT CO/CA/ Passive Investment

SC 13G/A 1 biiba2520923.htm PRIMECAP MANAGEMENT CO/CA/ UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 25)* Biogen Inc. (Name of Issuer) COM (Title of Class of Securities) 09062X103 (CUSIP Number) December 31, 2022 (Date of Event which Requires Filing of this Statement) Check the appropriate box to design

Employment Agreement, dated November 10, 2022, by and between Biogen Inc. and Christopher A. Viehbacher. Filed as Exhibit 10.1 to our Current Report on Form 8-K filed on November 10, 2022.

Exhibit 10.1 EXECUTION VERSION EMPLOYMENT AGREEMENT EMPLOYMENT AGREEMENT (?Agreement?) dated November 10, 2022 between BIOGEN INC., a Delaware corporation (the ?Company?), and Christopher A. Viehbacher (the ?Executive?). WHEREAS, the Company wishes to employ the Executive to serve as the Company?s President and Chief Executive Officer, and the Executive is willing to be employed and serve in such

Regulation FD Disclosure, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 10, 2022 Biogen Inc. (Exact name of Registrant as specified in its charter) Delaware 0-19311 33-0112644 (State of Incorporation) (Commission File Number) (I.R.S. Employer Ide

Biogen Names Christopher Viehbacher President and Chief Executive Officer Distinguished Industry Leader Brings Extensive International Experience in Large Pharmaceutical and Entrepreneurial Biotech Companies

Exhibit 99.1 Biogen Names Christopher Viehbacher President and Chief Executive Officer Distinguished Industry Leader Brings Extensive International Experience in Large Pharmaceutical and Entrepreneurial Biotech Companies CAMBRIDGE, Mass., November 10, 2022: Biogen Inc. (NASDAQ: BIIB) today announced that its Board of Directors has appointed Christopher A. Viehbacher as President and Chief Executiv

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

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, 2022 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

Biogen Reports Third Quarter 2022 Results

EX-99.1 2 exhibit991-q32022pressrele.htm EX-99.1 Biogen Reports Third Quarter 2022 Results •Third quarter revenue $2,508 million; GAAP diluted EPS $7.84; Non-GAAP diluted EPS $4.77 •Phase 3 study of lecanemab in early Alzheimer’s disease met the primary endpoint and all key secondary endpoints with highly statistically significant results •New data support the potential for zuranolone as a novel t

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 25, 2022 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

Prior Guidance Updated Guidance Total revenue $9.7 to $10.0 billion $9.9 to $10.1 billion Non-GAAP diluted EPS $14.25 to $16.00 $15.25 to $16.75

Biogen Reports Second Quarter 2022 Results ?Second quarter revenue $2,589 million; GAAP diluted EPS $7.

Prior Guidance Updated Guidance Total revenue $9.7 to $10.0 billion $9.9 to $10.1 billion Non-GAAP diluted EPS $14.25 to $16.00 $15.25 to $16.75

Biogen Reports Second Quarter 2022 Results ?Second quarter revenue $2,589 million; GAAP diluted EPS $7.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A (Amendment No. 1) CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 20, 2022 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commis

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2022 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

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 20, 2022 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

As filed with the Securities and Exchange Commission on July 6, 2022

As filed with the Securities and Exchange Commission on July 6, 2022 Registration No.

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 15, 2022 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Proxy State

Biogen Inc. Offer to Exchange up to $700,731,000 of our outstanding unregistered 3.250% Senior Notes due 2051 for a like principal amount of 3.250% Senior Notes due 2051 that have been registered under the Securities Act of 1933, as amended

Table of Contents Filed Pursuant to Rule 424(b)(3) Registration No. 333-265023 PROSPECTUS Biogen Inc. Offer to Exchange up to $700,731,000 of our outstanding unregistered 3.250% Senior Notes due 2051 for a like principal amount of 3.250% Senior Notes due 2051 that have been registered under the Securities Act of 1933, as amended Biogen Inc. is offering $700,731,000 aggregate principal amount of ne

Biogen Inc. 225 Binney Street Cambridge, Massachusetts 02142

Biogen Inc. 225 Binney Street Cambridge, Massachusetts 02142 May 24, 2022 VIA EDGAR Securities and Exchange Commission Division of Corporation Finance 100 F Street, N.E. Washington, D.C. 20549 Re: Biogen Inc. Registration Statement on Form S-4 File No. 333-265023 Request for Acceleration Ladies and Gentlemen: Pursuant to Rule 461 under the Securities Act of 1933, as amended, Biogen Inc. hereby req

LETTER

United States securities and exchange commission logo May 23, 2022 Susan H. Alexander, Esq. Executive Vice President and Chief Legal Officer Biogen Inc. 225 Binney Street Cambridge, Massachusetts 02142 Re: Biogen Inc. Registration Statement on Form S-4 Filed May 17, 2022 File No. 333-265023 Dear Ms. Alexander: This is to advise you that we have not reviewed and will not review your registration st

As filed with the Securities and Exchange Commission on May 17, 2022

Table of Contents As filed with the Securities and Exchange Commission on May 17, 2022 Registration No.

Form of Letter of Transmittal, filed herewith.

Exhibit 99.1 LETTER OF TRANSMITTAL FOR BIOGEN INC. OFFER TO EXCHANGE ANY AND ALL OUTSTANDING 3.250% SENIOR NOTES DUE 2051 ISSUED ON FEBRUARY 16, 2021 FOR A LIKE PRINCIPAL AMOUNT OF CORRESPONDING 3.250% SENIOR NOTES DUE 2051, WHICH HAVE BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED THE EXCHANGE OFFER EXPIRES AT 5:00 P.M., NEW YORK CITY TIME, ON , 2022 UNLESS EXTENDED (SUCH DATE AND T

Filing Fee Table, filed herewith.

EXHIBIT 107 Newly Registered and Carry Forward Securities Security Type Security Class Title Fee Calculation or Carry Forward Rule Amount Registered Proposed Maximum Offering Price Per Unit Maximum Aggregate Offering Price Fee Rate Amount of Registration Fee Carry Forward Form Type Carry Forward File Number Carry Forward Initial effective date Filing Fee Previously Paid In Connection with Unsold Securities to be Carried Forward Newly Registered Securities Fees to Be Paid Debt 3.

Form T-1 Statement of Eligibility of Trustee under the Trust Indenture Act of 1939, as amended, of U.S. Bank Trust Company, National Association, as trustee, filed herewith.

Exhibit 25 SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE ? Check if an Application to Determine Eligibility of a Trustee Pursuant to Section 305(b)(2) U.S. BANK TRUST COMPANY, NATIONAL ASSOCIATION (Exact name of Trustee as specified in its charter) 91-1821036 I.R.S. Emp

Biogen Inc. 2006 Non-Employee Directors Equity Plan, as amended. Filed as Exhibit 10.2 to our Quarterly Report on Form 10-Q for the quarter ended March 31, 2022.

EXHIBIT 10.2 BIOGEN INC. 2006 NON-EMPLOYEE DIRECTORS EQUITY PLAN (Approved by stockholders on May 25, 2006; as amended through March 27, 2015 and approved by stockholders on June 10, 2015; and as amended on April 6, 2022) 1. Purpose; Establishment. The Biogen Inc. 2006 Non-Employee Directors Equity Plan is intended to encourage ownership of shares of Common Stock by Non-Employee Directors of the C

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

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, 2022 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

BIOGEN REPORTS FIRST QUARTER 2022 RESULTS First quarter revenue $2,532 million; GAAP diluted EPS $2.06; Non-GAAP diluted EPS $3.62; EPS negatively impacted by $0.76 due to ADUHELM inventory write-offs As a result of the final national coverage determ

BIOGEN REPORTS FIRST QUARTER 2022 RESULTS First quarter revenue $2,532 million; GAAP diluted EPS $2.

egarding employment arrangement of Michel Vounatsos dated May 2, 2022

EXHIBIT 10.1 May 2, 2022 Michel Vounatsos c/o Biogen Inc. Re: Continued Employment During CEO Search Dear Michel: As we have discussed, the Board of Directors (the ?Board?) of Biogen Inc. (together with any of its subsidiaries, ?Biogen? or the ?Company?) intends to commence a search for a new Chief Executive Officer (?CEO?). This letter agreement (the ?Agreement?) reflects our mutual understanding

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): May 3, 2022 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (IRS

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Proxy State

Definitive Proxy Statement

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defi

BIIB / Biogen Inc / PRIMECAP MANAGEMENT CO/CA/ - PRIMECAP MANAGEMENT CO/CA/ Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 24)* Biogen Inc. (Name of Issuer) COM (Title of Class of Securities) 09062X103 (CUSIP Number) December 31, 2021 (Date of Event which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

BIIB / Biogen Inc / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 7)* Name of issuer: Biogen Inc. Title of Class of Securities: Common Stock CUSIP Number: 09062X103 Date of Event Which Requires Filing of this Statement: December 31, 2021 Check the appropriate box to designate the rule pursuant to which this Schedule is filed: ☒ Rule 13

BIOGEN REPORTS FOURTH QUARTER AND FULL YEAR 2021 RESULTS Revenue: Fourth quarter $2,734 million; Full Year $10,982 million GAAP diluted EPS: Fourth quarter $2.50; Full Year $10.40 Non-GAAP diluted EPS: Fourth quarter $3.39; Full Year $19.22 Engaging

BIOGEN REPORTS FOURTH QUARTER AND FULL YEAR 2021 RESULTS Revenue: Fourth quarter $2,734 million; Full Year $10,982 million GAAP diluted EPS: Fourth quarter $2.

Description of Securities.

Exhibit 4.8 DESCRIPTION OF THE REGISTRANT?S SECURITIES REGISTERED PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934 As of December 31, 2021, Biogen Inc. (the ?Company?) has six classes of securities registered under Section 12 of the Securities Exchange Act of 1934, as amended (the ?Exchange Act?): (1) Common Stock; (2) 3.625% Senior Notes due 2022; (3) 4.050% Senior Notes due 2025; (4

BIOGEN INC.

Exhibit 21 BIOGEN INC. The following is a list of subsidiaries of Biogen Inc. as of December 31, 2021, omitting some subsidiaries which, considered in the aggregate, would not constitute a significant subsidiary. SUBSIDIARY STATE OR OTHER JURISDICTION OF INCORPORATION OR ORGANIZATION Biogen Foundation Inc. Massachusetts Biogen MA Inc. Massachusetts Biogen Realty Corporation Massachusetts Biogen Re

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K ? ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2021 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 cha

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 3, 2022 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

Biogen Announces Nancy Leaming and Brian Posner to Retire from Board of Directors

Exhibit 99.1 Biogen Announces Nancy Leaming and Brian Posner to Retire from Board of Directors CAMBRIDGE, Mass., January 31, 2022? Biogen Inc. (Nasdaq: BIIB) today announced that Nancy Leaming and Brian Posner will retire from Biogen?s Board of Directors, effective at the time of the Company?s 2022 annual meeting of stockholders. Ms. Leaming, who joined the Biogen Board in 2008, was previously the

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 25, 2022 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 18, 2021 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number

Biogen Announces Alfred W. Sandrock, Jr. to Retire as Head of Research & Development

EX-99.1 2 d257656dex991.htm EX-99.1 Exhibit 99.1 Biogen Announces Alfred W. Sandrock, Jr. to Retire as Head of Research & Development CAMBRIDGE, Mass., November 15, 2021 — Biogen Inc. (Nasdaq: BIIB) announced today that Alfred “Al” W. Sandrock, Jr., M.D., Ph.D., Head of Research & Development, will retire from the Company effective December 31, 2021. A 23-year veteran of Biogen, Dr. Sandrock, 64,

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): November 15, 2021 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number

BIOGEN REPORTS THIRD QUARTER 2021 RESULTS Third quarter revenue $2,779 million; GAAP diluted EPS $2.22; Non-GAAP diluted EPS $4.77 Rolling submission initiated for lecanemab (BAN2401) in the U.S. and new data presented for aducanumab and BIIB080 (tau

BIOGEN REPORTS THIRD QUARTER 2021 RESULTS Third quarter revenue $2,779 million; GAAP diluted EPS $2.

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 20, 2021 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

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, 2021 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

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q ? QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2021 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

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 22, 2021 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

Amended and Restated Biogen Inc. 2019 Performance-Based Management Incentive Plan, effective as of June 2, 2021.

Exhibit 10.1 BIOGEN INC. PERFORMANCE-BASED MANAGEMENT INCENTIVE PLAN 1. Purpose This Performance-Based Management Incentive Plan (this ?Plan?) is established by Biogen Inc. (the ?Company?) to attract and retain persons of outstanding abilities and to stimulate efforts to bring about strong operating performance and reward the individuals who contribute to this performance. This Plan supersedes and

BIOGEN REPORTS SECOND QUARTER 2021 RESULTS Second quarter revenue $2,775 million; GAAP diluted EPS $2.99; Non-GAAP diluted EPS $5.68 Received accelerated approval for ADUHELM (aducanumab-avwa) in the U.S. for initiation of treatment in patients with

BIOGEN REPORTS SECOND QUARTER 2021 RESULTS Second quarter revenue $2,775 million; GAAP diluted EPS $2.

LETTER

United States securities and exchange commission logo June 22, 2021 Michael McDonnell Executive Vice President and Chief Financial Officer BIOGEN INC.

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June 21, 2021 By EDGAR Submission Division of Corporation Finance United States Securities and Exchange Commission 100 F Street, N.

LETTER

United States securities and exchange commission logo June 17, 2021 Michael McDonnell Executive Vice President and Chief Financial Officer BIOGEN INC.

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June 9, 2021 By EDGAR Submission Division of Corporation Finance United States Securities and Exchange Commission 100 F Street, N.

Certificate of Amendment of Biogen Inc.’s Amended and Restated Certificate of Incorporation, as amended.

Exhibit 3.1 CERTIFICATE OF AMENDMENT TO THE CERTIFICATE OF INCORPORATION OF BIOGEN INC. Pursuant to Section 242 of the General Corporation Law of the State of Delaware Biogen Inc. (hereinafter referred to as the ?Corporation?), a corporation duly organized and existing under the Delaware General Corporation Law (the ?DGCL?), does hereby certify as follows: FIRST: That at a meeting of the Board of

Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 2, 2021 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (IR

Notice of Exempt Solicitation

Notice of Exempt Solicitation Biogen Inc. (BIIB) Shareholder Alert Voluntary submission by James McRitchie 9295 Yorkship Ct., Elk Grove, CA 95758 Shareholder since 2010 Please vote for Proposal No. 5 by June 1, 2021 Stockholder Proposal: Disclose Lobbying Expenditures Your support is requested FOR Item 5 at the Biogen shareholder meeting on June 2, 2021. The proposal asks Biogen to prepare an annu

LETTER

United States securities and exchange commission logo May 13, 2021 Michael McDonnell Executive Vice President and Chief Financial Officer BIOGEN INC.

- DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Proxy State

- DEF 14A

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defi

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 22, 2021 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (

Quarterly Report - 10-Q

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, 2021 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

Joint Venture Agreement, dated December 6, 2011, by and between Samsung BioLogics Co., Ltd. and Biogen Therapeutics Inc. (f/k/a Biogen Idec Therapeutics Inc.), as amended February 28, 2012, September 29, 2014, and February 20, 2019.

Exhibit 10.1 CERTAIN INFORMATION CONTAINED IN THIS DOCUMENT, MARKED BY [***], HAS BEEN OMITTED BECAUSE IT IS BOTH NOT MATERIAL AND IS THE TYPE THAT BIOGEN INC. TREATS AS PRIVATE OR CONFIDENTIAL. JOINT VENTURE AGREEMENT THIS JOINT VENTURE AGREEMENT (this ?Agreement?) is entered into as of the 6th day of December 2011 by and between: (1) Samsung BioLogics Co., Ltd., a company organized and existing

BIOGEN REPORTS FIRST QUARTER 2021 RESULTS First quarter revenue $2,694 million; GAAP diluted EPS $2.69; Non-GAAP diluted EPS $5.34; 2021 earnings guidance raised Regulatory filings for aducanumab submitted in additional global markets Phase 2 study o

BIOGEN REPORTS FIRST QUARTER 2021 RESULTS First quarter revenue $2,694 million; GAAP diluted EPS $2.

Biogen Announces Two New Nominees for Election to Board of Directors

Biogen Announces Two New Nominees for Election to Board of Directors •Nominees bring diverse business and public health experience key to Biogen’s mission to pioneer and lead in neuroscience •Company thanks Director Robert W.

- PRE 14A

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Defi

- DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 Filed by the Registrant ? Filed by a Party other than the Registrant ? Check the appropriate box: ? Preliminary Proxy Statement ? Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ? Definitive Proxy State

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 7, 2021 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

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April 7, 2021 By EDGAR Submission Division of Corporation Finance United States Securities and Exchange Commission 100 F Street, N.

LETTER

United States securities and exchange commission logo March 25, 2021 Michael McDonnell Executive Vice President and Chief Financial Officer BIOGEN INC.

Form of 3.250% Senior Notes due 2051, in the form of a Global Note bearing a Regulation S legend. Filed as Exhibit 4.4 to our Current Report on Form 8-K filed on February 16, 2021.

EX-4.4 4 d124092dex44.htm EX-4.4 Exhibit 4.4 3.250% SENIOR NOTE DUE 2051 THIS NOTE IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (“DTC”), OR A NOMINEE OF DTC. THIS NOTE IS EXCHANGEABLE FOR NOTES REGISTERED IN THE NAME OF A PERSON OTHER THAN DTC OR ITS NOMINEE ONLY IN THE LIMITED

Registration Rights Agreement, dated February 16, 2021, between Biogen Inc. and Deutsche Bank Securities Inc. and Citigroup Global Markets, Inc. with respect to the 3.250% Senior Notes due 2051. Filed as Exhibit 4.5 to our Current Report on Form 8-K filed on February 16, 2021.

Exhibit 4.5 REGISTRATION RIGHTS AGREEMENT This REGISTRATION RIGHTS AGREEMENT dated February 16, 2021 (this ?Agreement?) is entered into by and among Biogen Inc., a Delaware corporation (the ?Company?), and Deutsche Bank Securities Inc. and Citigroup Global Markets Inc. as dealer managers (each, a ?Dealer Manager? and, together, the ?Dealer Managers?). The Company and the Dealer Managers are partie

Form of 3.250% Senior Notes due 2051, in the form of a Global Note bearing a private placement legend. Filed as Exhibit 4.3 to our Current Report on Form 8-K filed on February 16, 2021.

Exhibit 4.3 3.250% SENIOR NOTE DUE 2051 THIS NOTE IS A GLOBAL SECURITY WITHIN THE MEANING OF THE INDENTURE HEREINAFTER REFERRED TO AND IS REGISTERED IN THE NAME OF THE DEPOSITORY TRUST COMPANY, A NEW YORK CORPORATION (?DTC?), OR A NOMINEE OF DTC. THIS NOTE IS EXCHANGEABLE FOR NOTES REGISTERED IN THE NAME OF A PERSON OTHER THAN DTC OR ITS NOMINEE ONLY IN THE LIMITED CIRCUMSTANCES DESCRIBED IN THE I

Third Supplemental Indenture, dated February 16, 2021, between Biogen Inc. and U.S. Bank National Association. Filed as Exhibit 4.2 to our Current Report on Form 8-K filed on February 16, 2021.

Exhibit 4.2 BIOGEN INC., as Issuer and U.S. Bank National Association, as Trustee Third Supplemental Indenture Dated as of February 16, 2021 TABLE OF CONTENTS Page ARTICLE I DEFINITIONS SECTION 1 Section 1.1. Certain Terms Defined in the Base Indenture. 1 Section 1.2. Definitions. 2 ARTICLE II FORM AND TERMS OF THE NOTES 7 Section 2.1. Form and Dating. 7 Section 2.2. Terms of the Notes. 9 Section

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTIONS 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 16, 2021 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Numbe

SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 23)* Biogen Inc. (Name of Issuer) (Title of Class of Securities) (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement)

UNITED STATES OMB APPROVAL SECURITIES AND EXCHANGE COMMISSION OMB Number: 3235-0145 Washington, D.

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 6)*

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 6)* Name of issuer: Biogen Inc. Title of Class of Securities: Common Stock CUSIP Number: 09062X103 Date of Event Which Requires Filing of this Statement: December 31, 2020 Check the appropriate box to designate the rule pursuant to which this Schedule is filed: ☒ Rule 13

BIOGEN ANNOUNCES PRIVATE EXCHANGE OFFER FOR 5.200% SENIOR NOTES DUE 2045 OPEN TO CERTAIN INVESTORS

EX-99.1 Exhibit 99.1 BIOGEN ANNOUNCES PRIVATE EXCHANGE OFFER FOR 5.200% SENIOR NOTES DUE 2045 OPEN TO CERTAIN INVESTORS Cambridge, Mass., February 4, 2021 – Biogen Inc. (“Biogen”) (Nasdaq: BIIB) today announced the commencement of a private offer to exchange (the “Exchange Offer”) any and all of its outstanding 5.200% Senior Notes due 2045 (the “Old Notes”), totaling $1.75 billion in aggregate pri

BIOGEN ANNOUNCES CASH TENDER OFFER FOR 5.200% SENIOR NOTES DUE 2045 OPEN TO CERTAIN HOLDERS ONLY

EX-99.2 Exhibit 99.2 BIOGEN ANNOUNCES CASH TENDER OFFER FOR 5.200% SENIOR NOTES DUE 2045 OPEN TO CERTAIN HOLDERS ONLY Cambridge, Mass., February 4, 2021 – Biogen Inc. (“Biogen”) (Nasdaq: BIIB) today announced the commencement of an offer to purchase for cash (the “Cash Offer”) any and all of its outstanding 5.200% Senior Notes due 2045 (the “Notes”), totaling $1.75 billion in aggregate principal a

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTIONS 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 4, 2021 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number

Letter regarding employment arrangement of Chirfi Guindo dated October 12, 2017.

Biogen Exhibit 10.41 October 12, 2017 Chirfi Guindo [address] [address] Dear Chirfi, I am pleased to extend you this offer of employment to join Biogen with the job title of EVP, Global Commercial. This position will report to Michel Vounatsos, Chief Executive Officer. Please note that neither this letter nor any other materials constitute a contract of employment with Biogen. Your employment at B

Annual Report - 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2020 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 cha

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): February 3, 2021 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

BIOGEN INC.

Exhibit 21 BIOGEN INC. The following is a list of subsidiaries of Biogen Inc. as of December 31, 2020, omitting some subsidiaries which, considered in the aggregate, would not constitute a significant subsidiary. SUBSIDIARY STATE OR OTHER JURISDICTION OF INCORPORATION OR ORGANIZATION Biogen Foundation Inc. Massachusetts Biogen MA Inc. Massachusetts Biogen Realty Corporation Massachusetts Biogen Re

BIOGEN REPORTS FOURTH QUARTER AND FULL YEAR 2020 RESULTS Revenue: Fourth quarter $2,853 million; Full Year $13,445 million GAAP diluted EPS: Fourth quarter $2.32; Full Year $24.80 Non-GAAP diluted EPS: Fourth quarter $4.58; Full Year $33.70 Aducanuma

EX-99.1 2 exhibit991-q42020pressrele.htm EX-99.1 BIOGEN REPORTS FOURTH QUARTER AND FULL YEAR 2020 RESULTS Revenue: Fourth quarter $2,853 million; Full Year $13,445 million GAAP diluted EPS: Fourth quarter $2.32; Full Year $24.80 Non-GAAP diluted EPS: Fourth quarter $4.58; Full Year $33.70 Aducanumab for Alzheimer’s disease currently under regulatory review in the U.S., E.U., and Japan; PDUFA date

Second Supplemental Indenture, dated April 30, 2020, between Biogen Inc. and U.S. Bank National Association, including the forms of Global Notes attached as Exhibit A and Exhibit B, respectively, thereto. Filed as Exhibit 4.2 to our Current Report on Form 8-K filed on April 30, 2020.

Exhibit 4.4 DESCRIPTION OF THE REGISTRANT’S SECURITIES REGISTERED PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934 As of December 31, 2020, Biogen Inc. (the “Company”) has six classes of securities registered under Section 12 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”): (1) Common Stock; (2) 3.625% Senior Notes due 2022; (3) 4.050% Senior Notes due 2025; (4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G UNDER THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No.__) Sage Therapeutics, Inc. (Name of Issuer) Common Stock (Title of Class of Securities) (CUSIP Number) Decem

SC 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G UNDER THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No.) Sage Therapeutics, Inc. (Name of Issuer) Common Stock (Title of Class of Securities) 78667J108 (CUSIP Number) December 31, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which

BIIB / Biogen Inc. / PRIMECAP MANAGEMENT CO/CA/ - SC 13G/A Passive Investment

UNITED STATES OMB APPROVAL SECURITIES AND EXCHANGE COMMISSION OMB Number: 3235-0145 Washington, D.

BIOGEN REPORTS Q3 2020 RESULTS Third quarter revenue $3,376 million; GAAP diluted EPS $4.46; Non-GAAP diluted EPS $8.84 FDA accepted Biologics License Application for aducanumab with Priority Review Marketing Authorization Application for aducanumab

EX-99.1 2 exhibit991-q32020press.htm EX-99.1 BIOGEN REPORTS Q3 2020 RESULTS Third quarter revenue $3,376 million; GAAP diluted EPS $4.46; Non-GAAP diluted EPS $8.84 FDA accepted Biologics License Application for aducanumab with Priority Review Marketing Authorization Application for aducanumab submitted in Europe New collaboration with Denali Therapeutics bolsters pipeline for Parkinson’s disease

Quarterly Report - 10-Q

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, 2020 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

Financial Statements and Exhibits, Results of Operations and Financial Condition, Other Events - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): October 21, 2020 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

Separation Agreement between Biogen Inc. and Jeffrey Capello dated July 16, 2020.

Exhibit 10.3 BY ELECTRONIC DELIVERY ([email address]) July 16, 2020 Revised August 5, 2020 Jeff Capello [Address] Re: Separation Agreement Dear Jeff: The purpose of this Separation Agreement (the “Agreement”) is to confirm the terms of your separation from Biogen Inc. or one of its subsidiaries (“Biogen” or the “Company”). The specific severance pay and benefits being offered to you, and the terms

Biogen Inc. Executive Severance Policy - U.S. Executive Vice President, as amended effective July 13, 2020. Filed as Exhibit 10.1 to our Quarterly Report on Form 10-Q for the quarter ended September 30, 2020.

Exhibit 10.1 Severance Plan for U.S. Executive Vice Presidents As an Executive Vice President, you are entitled to severance benefits in the event your employment is terminated by Biogen other than For Cause or for reason of death or Disability (as these terms are defined in the Biogen Inc. 2017 Omnibus Equity Plan, as amended from time to time, or any successor plan there to (“OEP”). Benefits You

Letter regarding employment arrangement of Michael McDonnell dated July 16, 2020. Filed as Exhibit 10.2 to our Quarterly Report on Form 10-Q for the quarter ended September 30, 2020.

Exhibit 10.2 July 15, 2020 Dear Michael, I am pleased to extend you this offer of employment to join Biogen with the job title of Executive Vice President and Chief Financial Officer. This position will report to Michel Vounatsos, Chief Executive Officer. Please note that neither this letter nor any other materials constitute a contract of employment with Biogen. Your employment at Biogen is emplo

DNLI / Denali Therapeutics Inc. / BIOGEN INC. - SC 13G Passive Investment

SC 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G UNDER THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No.) Denali Therapeutics Inc. (Name of Issuer) Common Stock (Title of Class of Securities) 24823R105 (CUSIP Number) September 22, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to whic

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 15, 2020 BIOGEN INC. (E

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 15, 2020 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Numbe

BIOGEN REPORTS Q2 2020 REVENUES OF $3.7 BILLION GAAP diluted EPS increased 22%; Non-GAAP diluted EPS increased 12% Biogen completed submission of BLA for aducanumab in Alzheimer's disease in the U.S. New SPINRAZA data showed unprecedented survival in

EX-99.1 2 exhibit991-q22020press.htm EXHIBIT 99.1 BIOGEN REPORTS Q2 2020 REVENUES OF $3.7 BILLION GAAP diluted EPS increased 22%; Non-GAAP diluted EPS increased 12% Biogen completed submission of BLA for aducanumab in Alzheimer's disease in the U.S. New SPINRAZA data showed unprecedented survival in pre-symptomatic SMA Biogen presented positive phase 2 data in cutaneous lupus erythematosus Phase 1

Quarterly Report - 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-Q ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended June 30, 2020 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

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 22, 2020 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

Biogen Names Michael McDonnell as Executive Vice President and Chief Financial Officer

EX-99.1 Exhibit 99.1 Biogen Names Michael McDonnell as Executive Vice President and Chief Financial Officer CAMBRIDGE, Mass. – July 21, 2020 – Biogen Inc. (Nasdaq: BIIB) announced today the appointment of Michael (Mike) McDonnell as Executive Vice President and Chief Financial Officer, effective August 15, 2020. McDonnell joins Biogen from IQVIA™ (NYSE: IQV), where he is Executive Vice President a

Regulation FD Disclosure, Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): July 16, 2020 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 18, 2020 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (I

Financial Statements and Exhibits, Submission of Matters to a Vote of Security Holders

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): June 3, 2020 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (IR

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTIONS 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): April 27, 2020 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

Second Supplemental Indenture, dated April 30, 2020, between Biogen Inc. and U.S. Bank National Association, including the forms of Global Notes attached as Exhibit A and Exhibit B, respectively, thereto. Filed as Exhibit 4.2 to our Current Report on Form 8-K filed on April 30, 2020.

EX-4.2 Table of Contents Exhibit 4.2 BIOGEN INC., as Issuer and U.S. Bank National Association, as Trustee Second Supplemental Indenture Dated as of April 30, 2020 Table of Contents TABLE OF CONTENTS Page ARTICLE I DEFINITIONS SECTION 1 Section 1.1. Certain Terms Defined in the Indenture 1 Section 1.2. Definitions 2 ARTICLE II FORM AND TERMS OF THE NOTES 5 Section 2.1. Form and Dating 5 Section 2.

Underwriting Agreement, dated April 27, 2020, by and among the Company, Goldman Sachs & Co. LLC, BofA Securities, Inc. and J.P. Morgan Securities LLC, as representatives of the several underwriters named in Schedule I thereto.

EX-1.1 Exhibit 1.1 Execution Version Biogen Inc. 2.250% Senior Notes due 2030 3.150% Senior Notes due 2050 Underwriting Agreement April 27, 2020 Goldman Sachs & Co. LLC BofA Securities, Inc. J.P. Morgan Securities LLC As representatives of the several Underwriters named in Schedule I hereto, c/o Goldman Sachs & Co. LLC 200 West Street New York, New York 10282-2198 BofA Securities, Inc. One Bryant

CALCULATION OF REGISTRATION FEE Title of Each Class of Securities to Be Registered Amount to Be Registered Proposed Maximum Aggregate Offering Price Amount of Registration Fee(1) 2.250% Senior Notes Due 2030 $ 1,500,000,000 $ 1,500,000,000 $ 194,700

424B2 Table of Contents CALCULATION OF REGISTRATION FEE Title of Each Class of Securities to Be Registered Amount to Be Registered Proposed Maximum Aggregate Offering Price Amount of Registration Fee(1) 2.

Biogen Inc. $1,500,000,000 2.250% Senior Notes Due 2030 $1,500,000,000 3.150% Senior Notes Due 2050 PRICING TERM SHEET $1,500,000,000 2.250% Senior Notes Due 2030 Issuer Biogen Inc. Principal Amount $1,500,000,000 Maturity Date May 1, 2030 Issue Pric

FWP Filed pursuant to Rule 433 Registration No.: 333-237819 Free Writing Prospectus dated April 27, 2020 Relating to Preliminary Prospectus Supplement dated April 27, 2020 Biogen Inc. $1,500,000,000 2.250% Senior Notes Due 2030 $1,500,000,000 3.150% Senior Notes Due 2050 PRICING TERM SHEET $1,500,000,000 2.250% Senior Notes Due 2030 Issuer Biogen Inc. Principal Amount $1,500,000,000 Maturity Date

SUBJECT TO COMPLETION PRELIMINARY PROSPECTUS SUPPLEMENT DATED APRIL 27, 2020

424B2 Table of Contents Filed pursuant to Rule 424(b)(2) Registration No. 333-237819 The information in this preliminary prospectus supplement and the accompanying prospectus is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities and we are not soliciting an offer to buy these securities in any jurisdicti

- S-3ASR

S-3ASR Table of Contents As filed with the Securities and Exchange Commission on April 24, 2020 Registration No.

Form T-1 Statement of Eligibility of Trustee under the Trust Indenture Act of 1939, as amended, of U.S. Bank National Association, as trustee, filed herewith

EX-25 Exhibit 25 SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE ☐ Check if an Application to Determine Eligibility of a Trustee Pursuant to Section 305(b)(2) U.S. BANK NATIONAL ASSOCIATION (Exact name of Trustee as specified in its charter) 31-0841368 I.R.S. Employer Ide

Quarterly Report - 10-Q

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, 2020 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

BIOGEN REPORTS Q1 2020 REVENUES OF $3.5 BILLION GAAP diluted EPS increased 13%; Non-GAAP diluted EPS increased 31% Biogen has open BLA and has started to submit modules, expects to complete the U.S. filing for aducanumab in third quarter Biogen initi

BIOGEN REPORTS Q1 2020 REVENUES OF $3.5 BILLION GAAP diluted EPS increased 13%; Non-GAAP diluted EPS increased 31% Biogen has open BLA and has started to submit modules, expects to complete the U.S. filing for aducanumab in third quarter Biogen initiated re-dosing study for aducanumab and higher dose study for SPINRAZA Biogen entered collaboration with Sangamo Therapeutics for gene regulation ther

Financial Statements and Exhibits, Results of Operations and Financial Condition

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 22, 2020 BIOGEN INC. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (

Schedule 14A

Definitive Proxy Statement Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.

BIIB / Biogen Inc. DEFA14A - - DEFA14A

DEFA14A UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 14A PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE SECURITIES EXCHANGE ACT OF 1934 Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐ Check the appropriate box: ☐ Preliminary Proxy Statement ☐ Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) ☐ Definitive Pro

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): April 20, 2020 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number) (

SGMO / Sangamo BioSciences, Inc. / BIOGEN INC. - SC 13G Passive Investment

SC 13G UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE 13G UNDER THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No.) Sangamo Therapeutics, Inc. (Name of Issuer) Common Stock (Title of Class of Securities) 800677106 (CUSIP Number) April 8, 2020 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which t

BIIB / Biogen Inc. / PRIMECAP MANAGEMENT CO/CA/ - SC 13G/A Passive Investment

UNITED STATES OMB APPROVAL SECURITIES AND EXCHANGE COMMISSION OMB Number: 3235-0145 Washington, D.

BIIB / Biogen Inc. / VANGUARD GROUP INC - SCHEDULE 13G/A Passive Investment

SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 5)* Name of issuer: Biogen Inc Title of Class of Securities: Common Stock CUSIP Number: 09062X103 Date of Event Which Requires Filing of this Statement: December 31, 2019 Check the appropriate box to designate the rule pursuant to which this Schedule is filed: ☒ Rule 13d

IONS / Ionis Pharmaceuticals, Inc. / BIOGEN INC. - SC 13G/A Passive Investment

SC 13G/A CUSIP No. 462222100 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* Ionis Pharmaceuticals, Inc. (Name of Issuer) Common Stock, $0.001 par value (Title of Class of Securities) 462222100 (CUSIP Number) December 31, 2019 Date of Event Which Requires Filing of this Statement Check the appropriate

AGTC / Applied Genetic Technologies Corp / BIOGEN INC. - SC 13G/A Passive Investment

SC 13G/A CUSIP No. 03820J100 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* Applied Genetic Technologies Corporation (Name of Issuer) Common Stock, $0.001 par value (Title of Class of Securities) 03820J100 (CUSIP Number) December 31, 2019 Date of Event Which Requires Filing of this Statement Check th

Description of Securities.

Exhibit 4.4 DESCRIPTION OF THE REGISTRANT’S SECURITIES REGISTERED PURSUANT TO SECTION 12 OF THE SECURITIES EXCHANGE ACT OF 1934 As of December 31, 2019, Biogen Inc. (the “Company”) has five classes of securities registered under Section 12 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”): (1) Common Stock; (2) 2.900% Senior Notes due 2020; (3) 3.625% Senior Notes due 2022; (

Annual Report - 10-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Form 10-K ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2019 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 cha

BIOGEN INC.

Exhibit 21 BIOGEN INC. The following is a list of subsidiaries of Biogen Inc. as of December 31, 2019, omitting some subsidiaries which, considered in the aggregate, would not constitute a significant subsidiary. SUBSIDIARY STATE OR OTHER JURISDICTION OF INCORPORATION OR ORGANIZATION Biogen Foundation Inc. Massachusetts Biogen MA Inc. Massachusetts Biogen Realty Corporation Massachusetts Biogen Re

Entry into a Material Definitive Agreement, Termination of a Material Definitive Agreement, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): January 28, 2020 Biogen Inc. (Exact name of registrant as specified in its charter) Delaware 0-19311 33-0112644 (State or other jurisdiction of incorporation) (Commission File Number)

Credit Agreement, dated as of January 28, 2020, among Biogen Inc., Bank of America, N.A., as administrative agent, swing ling lender and the L/C issuer, and the other lenders party thereto. Filed as Exhibit 10.1 to our Current Report on Form 8-K filed on February 3, 2020.

EX-10.1 Exhibit 10.1 EXECUTION VERSION Published CUSIP Numbers: Deal: 09074KAC1 Revolver: 09074KAD9 CREDIT AGREEMENT Dated as of January 28, 2020 among BIOGEN INC., as the Borrower, BANK OF AMERICA, N.A., as Administrative Agent, Swing Line Lender and the L/C Issuer, CITIBANK, N.A., DEUTSCHE BANK AG, NEW YORK BRANCH, GOLDMAN SACHS BANK USA, JPMORGAN CHASE BANK, N.A., MIZUHO BANK (USA), MORGAN STAN