Biogen
BIIB
881 hedge funds and large institutions have $17.8B invested in Biogen in 2025 Q1 according to their latest regulatory filings, with 124 funds opening new positions, 332 increasing their positions, 272 reducing their positions, and 105 closing their positions.
22% more repeat investments, than reductions
Existing positions increased: 332 | Existing positions reduced: 272
18% more first-time investments, than exits
New positions opened: 124 | Existing positions closed: 105
1% more funds holding
Funds holding: 874 → 881 (+7)
1.98% less ownership
Funds ownership: 90.83% → 88.84% (-2%)
12% less capital invested
Capital invested by funds: $20.2B → $17.8B (-$2.45B)
44% less call options, than puts
Call options by funds: $345M | Put options by funds: $621M
60% less funds holding in top 10
Funds holding in top 10: 5 → 2 (-3)
Top Buyers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
AQR Capital Management
Greenwich,
Connecticut
|
+$119M |
| 2 |
Balyasny Asset Management
Chicago,
Illinois
|
+$106M |
| 3 |
SG Americas Securities
New York
|
+$103M |
| 4 |
Fidelity Investments
Boston,
Massachusetts
|
+$78.8M |
| 5 |
Point72 Asset Management
Stamford,
Connecticut
|
+$58.2M |
Top Sellers
| Rank | Fund | Capital Flow |
|---|---|---|
| 1 |
BGC
Beutel, Goodman & Co
Toronto,
Ontario, Canada
|
-$250M |
| 2 |
Pacer Advisors
Malvern,
Pennsylvania
|
-$188M |
| 3 |
T. Rowe Price Associates
Baltimore,
Maryland
|
-$112M |
| 4 |
JP Morgan Chase
New York
|
-$90.4M |
| 5 |
O
OrbiMed
New York
|
-$77.9M |
BIIB Hedge Fund Activity: Q1 2025 in Review
881 of the 7,458 institutional investors tracked by Wall St. Rank reported a position in Biogen (BIIB) for Q1 2025, worth a combined $17.8B — down 12% from $20.2B a quarter earlier.
Buyers outnumbered sellers: 124 funds opened new BIIB positions and 105 closed out — a net gain of 19 holders — while 332 added to existing stakes and 272 trimmed.
The largest buyer was AQR Capital Management, adding an estimated $119M. The largest seller was Beutel, Goodman & Co, cutting an estimated $250M.
- 881 institutional investors held Biogen (BIIB) as of Q1 2025, up from 874 in Q4 2024.
- Funds reported $17.8B of Biogen stock for Q1 2025, down 12% quarter-over-quarter.
- 124 funds opened new Biogen positions in Q1 2025 and 105 closed out, a net change of +19 holders.
- The largest Biogen buyer in Q1 2025 was AQR Capital Management, an estimated $119M added.
- The largest Biogen seller in Q1 2025 was Beutel, Goodman & Co, an estimated $250M sold.
Based on aggregated 13F filings for Q1 2025.