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BIOGEN INC. (BIIB) major ownership & activist stakes
| 13G/A | Passive 5%+ stake (13G) — amendment filed 2026-06-05 |
SEC.gov → |
| 13D/A | Possible activist stake (13D) — amendment filed 2026-05-14 |
SEC.gov → |
| 13G/A | Passive 5%+ stake (13G) — amendment filed 2026-05-06 |
SEC.gov → |
| 13G | Passive 5%+ stake (13G) filed 2026-04-29 |
SEC.gov → |
| 13D | Possible activist stake (13D) filed 2026-04-06 |
SEC.gov → |
| 13G/A | Passive 5%+ stake (13G) — amendment filed 2026-03-26 |
SEC.gov → |
| 13G | Passive 5%+ stake (13G) filed 2026-02-05 |
SEC.gov → |
| 13G/A | Passive 5%+ stake (13G) — amendment filed 2025-11-13 |
SEC.gov → |
| 13G | Passive 5%+ stake (13G) filed 2025-11-10 |
SEC.gov → |
| 13D/A | Possible activist stake (13D) — amendment filed 2025-07-30 |
SEC.gov → |
| 13D/A | Possible activist stake (13D) — amendment filed 2025-07-21 |
SEC.gov → |
| 13G/A | Passive 5%+ stake (13G) — amendment filed 2025-04-17 |
SEC.gov → |
A 13D signals a large holder who may push for change; a 13G is a passive 5%+ position. Who the filer is and what they want is decoded in the app.
Who just took a 5%+ position in BIIB — and are they activists? Get the filer and their intent in plain English.
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