BIOGEN INC. — Director's Dealing 2025

Feb 10, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN INC. (BIIB)
CIK: 0000875045
Period of Report: 2025-02-07

Reporting Person: MCDONNELL MICHAEL R (EVP, Chief Financial Officer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-02-07	Common Stock	M	2335	—	Acquired	21741	Direct
2025-02-07	Common Stock	F	786	$141.35	Disposed	20955	Direct
2025-02-07	Common Stock	M	2216	—	Acquired	23171	Direct
2025-02-07	Common Stock	F	716	$141.35	Disposed	22455	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-02-07	Restricted Stock Unit	$0	M	2335	Disposed	2026-02-08	Common Stock (2335)	Direct
2025-02-07	Restricted Stock Unit	$0	M	2216	Disposed	2027-02-07	Common Stock (2216)	Direct

Footnotes

F1: The restricted stock units vest in three (3) equal annual installments commencing one year after the grant date of 02/8/2023.

F2: The restricted stock units vest in three (3) equal annual installments, commencing one year after the grant date of 02/07/2024.