BlackRock, Inc. - 31 Mar 2025 SCHEDULE 13G/A Report for BIOGEN INC Common Stock (BIIB)

Filing Manager: BlackRock, Inc.
Reporting Manager: BlackRock, Inc.
Security: BIOGEN INC Common Stock
Symbol: BIIB
Shares outstanding: 147M shares
Disclosed Ownership: 12.5M shares
Ownership: 8.5%
Form type: SCHEDULE 13G/A
Filing time: 17 Apr 2025, 09:35:28 UTC
Date of event: 31 Mar 2025
SEC: View on sec.gov

Reporting Managers (1)

Name	Ownership	Shares Owned	sole voting power	shared voting power	Signature	Title	CIK
BlackRock, Inc.	8.5%	12.5M	11.1M	0	Spencer Fleming	Managing Director