| Name | Relationship | Address | Signature | Signature date | CIK |
|---|---|---|---|---|---|
| DORSA CAROLINE | Director | BIOGEN INC., 225 BINNEY STREET, CAMBRIDGE | /s/ Wendell Taylor, Attorney in Fact for Caroline D. Dorsa | 18 Jun 2025 | 0001181174 |
| Type | Sym | Class | Transaction | Value $ | Shares | Change % | * Price $ | Shares After | Date | Ownership | Footnotes |
|---|---|---|---|---|---|---|---|---|---|---|---|
| transaction | BIIB | Common Stock | Award | $0 | +3,160 | +11% | $0.000000 | 31,002 | 17 Jun 2025 | Direct |