FMR LLC
· Added
+$623M
Change
+3.4M
Δ Own
+35.9%
Date
Q1 2026
BI
| Investor | Type | Est. change | Change | Δ Own | Date | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
FMR LLC
· Added
+$623M
Change
+3.4M
Δ Own
+35.9%
Date
Q1 2026
|
FMR LLC | Added· Q1 2026 | +$623M | +3.4M | +35.9% | Q1 2026 | |||||
|
Norges
· Exited
−$486M
Change
−2.6M
Δ Own
−100.0%
Date
Q1 2026
|
Norges | Exited· Q1 2026 | −$486M | −2.6M | −100.0% | Q1 2026 | |||||
|
Point72 Asset Management, L.P.
· Reduced
−$369M
Change
−2.0M
Δ Own
−71.2%
Date
Q1 2026
|
Point72 Asset Management, L.P. | Reduced· Q1 2026 | −$369M | −2.0M | −71.2% | Q1 2026 | |||||
|
BlackRock
· Added
+$214M
Change
+1.2M
Date
Q1 2026
|
BlackRock | Added· Q1 2026 | +$214M | +1.2M | – | Q1 2026 | |||||
|
Pacer Advisors, Inc.
· Exited
−$211M
Change
−1.1M
Δ Own
−100.0%
Date
Q1 2026
|
Pacer Advisors, Inc. | Exited· Q1 2026 | −$211M | −1.1M | −100.0% | Q1 2026 | |||||
|
Millennium Management LLC
· Reduced
−$190M
Change
−1.0M
Date
Q1 2026
|
Millennium Management LLC | Reduced· Q1 2026 | −$190M | −1.0M | – | Q1 2026 | |||||
|
Barclays PLC
· Reduced
−$139M
Change
−754K
Date
Q1 2026
|
Barclays PLC | Reduced· Q1 2026 | −$139M | −754K | – | Q1 2026 | |||||
|
Wellington Management Group LLP
· Reduced
−$109M
Change
−590K
Δ Own
−16.6%
Date
Q1 2026
|
Wellington Management Group LLP | Reduced· Q1 2026 | −$109M | −590K | −16.6% | Q1 2026 | |||||
|
Susquehanna International Group, LLP
· Reduced
−$96M
Change
−521K
Date
Q1 2026
|
Susquehanna International Group, LLP | Reduced· Q1 2026 | −$96M | −521K | – | Q1 2026 | |||||
|
AQR Capital Management LLC
· Added
+$73M
Change
+395K
Date
Q1 2026
|
AQR Capital Management LLC | Added· Q1 2026 | +$73M | +395K | – | Q1 2026 | |||||
|
Hrt Financial LP
· Exited
−$71M
Change
−384K
Δ Own
−100.0%
Date
Q1 2026
|
Hrt Financial LP | Exited· Q1 2026 | −$71M | −384K | −100.0% | Q1 2026 | |||||
|
Jain Global LLC
· Exited
−$65M
Change
−353K
Δ Own
−100.0%
Date
Q1 2026
|
Jain Global LLC | Exited· Q1 2026 | −$65M | −353K | −100.0% | Q1 2026 | |||||
|
Artemis Investment Management LLP
· Added
+$63M
Change
+345K
Date
Q1 2026
|
Artemis Investment Management LLP | Added· Q1 2026 | +$63M | +345K | – | Q1 2026 | |||||
|
Two Sigma Investments, LP
· Reduced
−$45M
Change
−242K
Δ Own
−96.2%
Date
Q1 2026
|
Two Sigma Investments, LP | Reduced· Q1 2026 | −$45M | −242K | −96.2% | Q1 2026 | |||||
|
Causeway Capital Management LLC
· Reduced
−$44M
Change
−240K
Date
Q1 2026
|
Causeway Capital Management LLC | Reduced· Q1 2026 | −$44M | −240K | – | Q1 2026 | |||||
| Insider | Title | Type | Price | Qty | Value | Owned | ΔOwn | Trade date | Filed date | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Hawkins William A.
· Director
Grant (A)
2K
|
Hawkins William A. | Director | Grant (A) | – | 2K | – | 10K | – | Jun 9, 2026 | Jun 11, 2026 | |||||||||
|
Sherwin Stephen A.
· Director
Grant (A)
2K
|
Sherwin Stephen A. | Director | Grant (A) | – | 2K | – | 15K | – | Jun 9, 2026 | Jun 11, 2026 | |||||||||
|
Rowinsky Eric K.
· Director
Grant (A)
2K
|
Rowinsky Eric K. | Director | Grant (A) | – | 2K | – | 26K | – | Jun 9, 2026 | Jun 11, 2026 | |||||||||
|
Mantas Jesus B.
· Director
Grant (A)
2K
|
Mantas Jesus B. | Director | Grant (A) | – | 2K | – | 11K | – | Jun 9, 2026 | Jun 11, 2026 | |||||||||
|
Langer Susan
· Director
Grant (A)
2K
|
Langer Susan | Director | Grant (A) | – | 2K | – | 7K | – | Jun 9, 2026 | Jun 11, 2026 | |||||||||
|
Patolawala Monish D.
· Director
Grant (A)
2K
|
Patolawala Monish D. | Director | Grant (A) | – | 2K | – | 5K | – | Jun 9, 2026 | Jun 11, 2026 | |||||||||
|
Pangalos Menelas N.
· Director
2 operations
0
|
Pangalos Menelas N. | Director | 2 operations | – | 0 | – | 0 | – | Jun 9, 2026 | Jun 11, 2026 | |||||||||
|
Pangalos Menelas N.
· Director
Grant (A)
2K
|
Pangalos Menelas N. | Director | Grant (A) | – | 2K | – | 4K | – | Jun 9, 2026 | Jun 11, 2026 | |||||||||
|
Minor Lloyd
· Director
Grant (A)
2K
|
Minor Lloyd | Director | Grant (A) | – | 2K | – | 4K | – | Jun 9, 2026 | Jun 11, 2026 | |||||||||
|
Freire Maria C.
· Director
Grant (A)
2K
|
Freire Maria C. | Director | Grant (A) | – | 2K | – | 9K | – | Jun 9, 2026 | Jun 11, 2026 | |||||||||
|
Keeney Adam
· Officer
2 operations
0
|
Keeney Adam | Officer | 2 operations | – | 0 | – | 0 | – | May 1, 2026 | May 5, 2026 | |||||||||
|
Keeney Adam
· Officer
Tax withholding or exercise payment (F)
-$85K
|
Keeney Adam | Officer | Tax withholding or exercise payment (F) | $187.06 | -455 | -$85K | 6K | – | May 1, 2026 | May 5, 2026 | |||||||||
|
Godbout Sean
· Officer
2 operations
0
|
Godbout Sean | Officer | 2 operations | – | 0 | – | 364 | – | Apr 1, 2026 | Apr 3, 2026 | |||||||||
|
Godbout Sean
· Officer
Tax withholding or exercise payment (F)
-$10K
|
Godbout Sean | Officer | Tax withholding or exercise payment (F) | $183.78 | -54 | -$10K | 1K | – | Apr 1, 2026 | Apr 3, 2026 | |||||||||
|
Viehbacher Christopher
· Director
Grant (A)
38K
|
Viehbacher Christopher | Director | Grant (A) | – | 38K | – | 38K | – | Feb 13, 2026 | Feb 17, 2026 | |||||||||
N
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A
A
918 reporting institutions disclosed BIIB position changes in the Q1 2026 snapshot.
For each manager, WhoBought compares accepted consecutive 13F share counts. Share change is current shares minus prior shares. Estimated dollar change is that signed share change multiplied by the split-adjusted quarter-mean close. The activity table on this page uses Q1 2026.
An investor crossing 5% of a share class generally files Schedule 13D for activist intent or Schedule 13G for a passive position. The technical form names appear here rather than in the activity rows.
Ownership and institutional activity come from SEC Form 13F filings. Insider activity comes from SEC Form 4, and large-shareholder activity from SEC Schedules 13D and 13G. FMP supplies price data only. Company logos use the local verified Parqet cache with one shared fallback.
Form 13F is a quarterly disclosure and is normally filed after the quarter ends. Every ownership and activity value therefore names its represented period; it is not presented as a live position.
A muted dash marks a missing table value. It means the filing omitted the value, comparable data is unavailable, or no prior position exists for comparison.