Biogen Inc.
BIIB- Exchange
- Nasdaq
- Industry
- Biological Products, (No Diagnostic Substances)
- SEC CIK
- 0000875045
In the last 90 days, Biogen Inc. insiders filed 0 open-market purchases and 1 sale; 1,047 institutions reported holding it in 13F filings for Q2 2026, worth $30.7B in total; no superinvestor holds it.
13F holders, Q1 2026
Institutional positions in Biogen Inc. as of Mar 31, 2026. Investment managers with $100 million or more in US stocks report their long positions on Form 13F within 45 days after each quarter ends. How 13F works
- Institutional holders
- 1,015
- +33 vs. Q4 2025
- Shares held
- 135.0M
- +15.4M (+12.9%) vs. Q4 2025
- Total value
- $24.7B
- +$3.70B (+17.6%) vs. Q4 2025
- New holders
- 138
- 402 more added
- Sold out
- 105
- 290 more reduced
20 institutions that held it in Q4 2025 haven't filed for Q1 2026 yet. Not filing isn't selling, so they aren't counted as sold out or in the changes above.
Compare with Q4 2025: new holders, sold out and not filed yet
Holders and value by quarter
Institutions reporting BIIB on Form 13F each quarter since Q1 2021, and the total value they reported. Values are as of each quarter end, so they also move with the share price.
| Quarter | Holders | Value |
|---|---|---|
| Q2 2026 | 1,047 | $30.7B |
| Q1 2026 | 1,015 | $24.7B |
| Q4 2025 | 1,002 | $24.6B |
| Q3 2025 | 909 | $18.4B |
| Q2 2025 | 867 | $16.3B |
| Q1 2025 | 882 | $17.7B |
| Q4 2024 | 879 | $20.2B |
| Q3 2024 | 921 | $25.1B |
| Q2 2024 | 947 | $29.9B |
| Q1 2024 | 955 | $28.0B |
| Q4 2023 | 1,005 | $33.3B |
| Q3 2023 | 966 | $32.2B |
| Q2 2023 | 1,009 | $36.1B |
| Q1 2023 | 1,004 | $35.0B |
| Q4 2022 | 1,033 | $34.6B |
| Q3 2022 | 987 | $33.0B |
| Q2 2022 | 930 | $25.0B |
| Q1 2022 | 954 | $25.9B |
| Q4 2021 | 1,014 | $29.7B |
| Q3 2021 | 1,044 | $35.1B |
| Q2 2021 | 1,107 | $43.6B |
| Q1 2021 | 1,096 | $35.7B |
Institutions, Q1 2026
Shares, value and share of portfolio for each institution holding Biogen Inc.; share changes are against Q4 2025.