Ticker · CUSIP 09062X103
Holders (tracked)
21
Combined shares
15,549,779
Combined value
$2.60B
Last close
—
Quarter
2025Q4
Tracked holders · last 8 quarters
+3 vs previous quarter over the last 8.
SEC event timeline
27 events
- Wellington Management trimmed2026-02-17−695,235 shares · 2025Q413F
- Ken Griffin (Citadel Advisors) trimmed2026-02-17−332,304 shares · 2025Q413F
- Two Sigma Investments added2026-02-17+46,530 shares · 2025Q413F
- Izzy Englander (Millennium Mgmt) added2026-02-17+14,396 shares · 2025Q413F
- AQR Capital Management trimmed2026-02-17−254,965 shares · 2025Q413F
- Steve Cohen (Point72) trimmed2026-02-17−1,059,709 shares · 2025Q413F
- T. Rowe Price trimmed2026-02-17−173,386 shares · 2025Q413F
- +33,300 shares · 2025Q413F
- +290,605 shares · 2025Q413F
- D.E. Shaw & Co. trimmed2026-02-17−424,170 shares · 2025Q413F
- −39,983 shares · 2025Q413F
- Renaissance Technologies trimmed2026-02-12−565,210 shares · 2025Q413F
- Norges Bank (Norway SWF) opened position2026-02-10+2,638,834 shares · 2025Q413F
- Ken Fisher (Fisher Asset Mgmt) added2026-02-09+15,984 shares · 2025Q413F
- −6,000 shares · 2025Q313F
- Steve Cohen (Point72) added2025-11-14+41,174 shares · 2025Q313F
- Two Sigma Investments trimmed2025-11-14−302,306 shares · 2025Q313F
- D.E. Shaw & Co. trimmed2025-11-14−888,283 shares · 2025Q313F
- Izzy Englander (Millennium Mgmt) added2025-11-14+435,688 shares · 2025Q313F
- T. Rowe Price added2025-11-14+131,530 shares · 2025Q313F
- Wellington Management trimmed2025-11-14−551,916 shares · 2025Q313F
- AQR Capital Management added2025-11-14+418,776 shares · 2025Q313F
- Renaissance Technologies trimmed2025-11-13−80,700 shares · 2025Q313F
- Norges Bank (Norway SWF) exited2025-11-13−2,264,177 shares · 2025Q313F
- +39,983 shares · 2025Q313F
- Ken Fisher (Fisher Asset Mgmt) trimmed2025-11-12−11,852 shares · 2025Q313F
- Norges Bank (Norway SWF) added2025-11-12+185,647 shares · 2024Q313F
Insider activity
No insider transactions in the last 30 days.
Who moved on this name in 2025Q4
13F transactions reported for the latest quarter, grouped by direction.
New positions3
- Norges Bank (Norway SWF)+2,638,834$464.4M
- Larry Robbins (Glenview Capital)+290,605$51.1M
- Paul Tudor Jones (Tudor Investment)+33,300$5.9M
Added to3
- Two Sigma Investments+46,530$8.2M
- Ken Fisher (Fisher Asset Mgmt)+15,984$2.8M
- Izzy Englander (Millennium Mgmt)+14,396$2.5M
Trimmed7
- Steve Cohen (Point72)−1,059,709$186.5M
- Wellington Management−695,235$122.4M
- Renaissance Technologies−565,210$99.5M
- D.E. Shaw & Co.−424,170$74.6M
- Ken Griffin (Citadel Advisors)−332,304$58.5M
- AQR Capital Management−254,965$44.9M
- T. Rowe Price−173,386$31K
Exited1
- Ray Dalio (Bridgewater Associates)−39,983$5.6M
Institutional ownership over time
Distinct super-investors holding this ticker · combined dollar value, by quarter.
| Quarter | Holders | Combined value |
|---|---|---|
| 2022Q1 | 21 | $294.64B |
| 2022Q2 | 20 | $246.46B |
| 2022Q3 | 21 | $340.3M |
| 2022Q4 | 21 | $7.43B |
| 2023Q1 | 18 | $6.95B |
| 2023Q2 | 19 | $6.83B |
| 2023Q3 | 18 | $4.45B |
| 2023Q4 | 17 | $4.28B |
| 2024Q1 | 17 | $4.73B |
| 2024Q2 | 20 | $5.48B |
| 2024Q3 | 20 | $2.10B |
| 2024Q4 | 19 | $1.23B |
| 2025Q1 | 19 | $1.74B |
| 2025Q2 | 21 | $2.26B |
| 2025Q3 | 18 | $2.12B |
| 2025Q4 | 21 | $2.60B |
Congress members trading this stock
| Date | Member | Type | Amount range | Filing |
|---|---|---|---|---|
| 2026-01-30 | Gilbert Cisneros | Buy | $1K – $15K | PDF ↗ |
| 2025-05-15 | Rob Bresnahan | Buy | $1K – $15K | PDF ↗ |
| 2025-04-08 | Rob Bresnahan | Sell | $1K – $15K | PDF ↗ |
| 2025-02-25 | Rob Bresnahan | Buy | $1K – $15K | PDF ↗ |
Who owns BIIB
21 super-investors · 2025Q4
Tracked stake
15.55M
shares
Combined value
$2.60B
% of shares outstanding
—
shares-out unknown
Quarter action mix
New4Added5Trim12
| # | Manager | Shares | Value |
|---|---|---|---|
| 1 | Wellington Management | 3.55M | $625M |
| 2 | Steve Cohen Point72 | 2.81M | $495M |
| 3 | Norges Bank Norway SWF | 2.64M | $464M |
| 4 | AQR Capital Management | 1.53M | $269M |
| 5 | Izzy Englander Millennium Mgmt | 1.13M | $198M |
| 6 | Steve Cohen Point72 | 1.00M | $176M |
| 7 | Ken Griffin Citadel Advisors | 407.0K | $72M |
| 8 | Renaissance Technologies | 399.2K | $70M |
| 9 | Ken Fisher Fisher Asset Mgmt | 293.3K | $52M |
| 10 | Larry Robbins Glenview Capital | 290.6K | $51M |
| 11 | Two Sigma Investments | 251.8K | $44M |
| 12 | Ken Griffin Citadel Advisors | 162.0K | $29M |
| 13 | Izzy Englander Millennium Mgmt | 101.1K | $18M |
| 14 | D.E. Shaw & Co. | 53.8K | $9M |
| 15 | Izzy Englander Millennium Mgmt | 46.7K | $8M |
| 16 | Ken Griffin Citadel Advisors | 40.4K | $7M |
| 17 | Paul Tudor Jones Tudor Investment | 23.0K | $4M |
| 18 | D.E. Shaw & Co. | 13.2K | $2M |
| 19 | Paul Tudor Jones Tudor Investment | 10.3K | $2M |
| 20 | D.E. Shaw & Co. | 6.4K | $1M |
| 21 | T. Rowe Price | 792.1K | $139K |
Recent moves
20 transactions
- TRIMD.E. Shaw & Co.−424,170 · 2025Q4
- −1,059,709 · 2025Q4
- −695,235 · 2025Q4
- +33,300 · 2025Q4
- +46,530 · 2025Q4
- TRIMT. Rowe Price−173,386 · 2025Q4
- −254,965 · 2025Q4
- +14,396 · 2025Q4
- −332,304 · 2025Q4
- +290,605 · 2025Q4
- −39,983 · 2025Q4
- −565,210 · 2025Q4
- +2,638,834 · 2025Q4
- +15,984 · 2025Q4
- −6,000 · 2025Q3
- +435,688 · 2025Q3
- TRIMD.E. Shaw & Co.−888,283 · 2025Q3
- +41,174 · 2025Q3
- −302,306 · 2025Q3
- +131,530 · 2025Q3
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