BIOGEN INC. — Director's Dealing 2026

Feb 10, 2026

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: BIOGEN INC. (BIIB)
CIK: 0000875045
Period of Report: 2026-02-06

Reporting Person: Singhal Priya (Head of Development)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2026-02-06	Common Stock	M	2217	—	Acquired	8488.1428	Direct
2026-02-06	Common Stock	F	1056	$201.18	Disposed	7432.1428	Direct
2026-02-06	Common Stock	M	4683	—	Acquired	12115.1428	Direct
2026-02-06	Common Stock	F	1412	$201.18	Disposed	10703.1428	Direct
2026-02-09	Common Stock	S	2660	$199.83	Disposed	8043.1428	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2026-02-06	Restricted Stock Unit	$0	M	2217	Disposed	2027-02-07	Common Stock (2217)	Direct
2026-02-06	Restricted Stock Unit	$0	M	4683	Disposed	2028-02-06	Common Stock (4683)	Direct

Footnotes

F1: The restricted stock units vest in three (3) equal annual installments, commencing one year after the grant date of 02/07/2024.

F2: The restricted stock units vest in three equal yearly installments beginning on the first anniversary of the grant date of February 6, 2025.