BlackRock
· Reduced
Change
−3.2M
Date
Q1 2026
AR
| Investor | Type | Est. change | Change | Δ Own | Date | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
BlackRock
· Reduced
Change
−3.2M
Date
Q1 2026
|
BlackRock | Reduced· Q1 2026 | – | −3.2M | – | Q1 2026 | |||||
|
Invesco Ltd.
· Added
Change
+2.7M
Δ Own
+498.9%
Date
Q1 2026
|
Invesco Ltd. | Added· Q1 2026 | – | +2.7M | +498.9% | Q1 2026 | |||||
|
Slate Path Capital LP
· Exited
Change
−2.5M
Δ Own
−100.0%
Date
Q1 2026
|
Slate Path Capital LP | Exited· Q1 2026 | – | −2.5M | −100.0% | Q1 2026 | |||||
|
Norges
· Exited
Change
−1.7M
Δ Own
−100.0%
Date
Q1 2026
|
Norges | Exited· Q1 2026 | – | −1.7M | −100.0% | Q1 2026 | |||||
|
Fred Alger Management, LLC
· Added
Change
+1.5M
Date
Q1 2026
|
Fred Alger Management, LLC | Added· Q1 2026 | – | +1.5M | – | Q1 2026 | |||||
|
Arrowstreet Capital, Limited Partnership
· Reduced
Change
−1.5M
Date
Q1 2026
|
Arrowstreet Capital, Limited Partnership | Reduced· Q1 2026 | – | −1.5M | – | Q1 2026 | |||||
|
Vestal Point Capital, LP
· Added
Change
+1.4M
Date
Q1 2026
|
Vestal Point Capital, LP | Added· Q1 2026 | – | +1.4M | – | Q1 2026 | |||||
|
Hood River Capital Management LLC
· New
Change
+1.1M
Date
Q1 2026
|
Hood River Capital Management LLC | New· Q1 2026 | – | +1.1M | – | Q1 2026 | |||||
|
D. E. Shaw & Co., Inc.
· Added
Change
+1.0M
Δ Own
+710.5%
Date
Q1 2026
|
D. E. Shaw & Co., Inc. | Added· Q1 2026 | – | +1.0M | +710.5% | Q1 2026 | |||||
|
Change
+1.0M
Date
Q1 2026
|
Renaissance Technologies LLC | New· Q1 2026 | – | +1.0M | – | Q1 2026 | |||||
|
Geode
· Added
Change
+1.0M
Date
Q1 2026
|
Geode | Added· Q1 2026 | – | +1.0M | – | Q1 2026 | |||||
|
Vanguard
· Reduced
Change
−939K
Date
Q1 2026
|
Vanguard | Reduced· Q1 2026 | – | −939K | – | Q1 2026 | |||||
|
FMR LLC
· Added
Change
+746K
Δ Own
+11.4%
Date
Q1 2026
|
FMR LLC | Added· Q1 2026 | – | +746K | +11.4% | Q1 2026 | |||||
|
American Century Companies Inc
· Added
Change
+644K
Date
Q1 2026
|
American Century Companies Inc | Added· Q1 2026 | – | +644K | – | Q1 2026 | |||||
|
Assenagon Asset Management S.A.
· Reduced
Change
−626K
Date
Q1 2026
|
Assenagon Asset Management S.A. | Reduced· Q1 2026 | – | −626K | – | Q1 2026 | |||||
| Insider | Title | Type | Price | Qty | Value | Owned | ΔOwn | Trade date | Filed date | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Cohen Matthew Gregory
· Director
Grant (A)
12K
|
Cohen Matthew Gregory | Director | Grant (A) | – | 12K | – | 12K | – | Jun 15, 2026 | Jun 17, 2026 | |||||||||
|
Lu Hongbo
· Director
Sell
−$228K
|
Lu Hongbo | Director | Sell | $76.88 | −3K | −$228K | 52K | – | May 12, 2026 | May 14, 2026 | |||||||||
|
Hamilton James C.
· Officer
Sell
−$750K
|
Hamilton James C. | Officer | Sell | $75.00 | −10K | −$750K | 227K | – | Apr 23, 2026 | Apr 24, 2026 | |||||||||
|
Apel Daniel Joseph
· CFO
3 operations
−$934K
|
Apel Daniel Joseph | CFO | 3 operations | $70.11–$71.92 | −13K | −$934K | 163K | – | Apr 22, 2026 | Apr 24, 2026 | |||||||||
|
Hamilton James C.
· Officer
Sell
−$642K
|
Hamilton James C. | Officer | Sell | $64.19 | −10K | −$642K | 237K | – | Mar 5, 2026 | Mar 9, 2026 | |||||||||
|
Hamilton James C.
· Officer
Grant (A)
75K
|
Hamilton James C. | Officer | Grant (A) | – | 75K | – | 247K | – | Jan 6, 2026 | Jan 8, 2026 | |||||||||
|
Apel Daniel Joseph
· CFO
Grant (A)
75K
|
Apel Daniel Joseph | CFO | Grant (A) | – | 75K | – | 176K | – | Jan 6, 2026 | Jan 8, 2026 | |||||||||
|
O'Brien Patrick
· Officer
5 operations
-2K
|
O'Brien Patrick | Officer | 5 operations | – | -2K | – | 473K | – | Jan 6, 2026 | Jan 8, 2026 | |||||||||
|
O'Brien Patrick
· Officer
Grant (A)
75K
|
O'Brien Patrick | Officer | Grant (A) | – | 75K | – | 547K | – | Jan 6, 2026 | Jan 8, 2026 | |||||||||
|
O'Brien Patrick
· Officer
12 operations
−$3.1M
|
O'Brien Patrick | Officer | 12 operations | $61.12–$68.00 | −49K | −$3.1M | 475K | – | Jan 5, 2026 | Jan 5, 2026 | |||||||||
|
Hamilton James C.
· Officer
7 operations
−$2.5M
|
Hamilton James C. | Officer | 7 operations | $61.24–$68.00 | −40K | −$2.5M | 174K | – | Jan 5, 2026 | Jan 5, 2026 | |||||||||
|
Anzalone Christopher Richard
· Director, Officer
2 operations
−$872K
|
Anzalone Christopher Richard | Director, Officer | 2 operations | $65.88–$66.39 | −13K | −$872K | 3.8M | – | Jan 2, 2026 | Jan 5, 2026 | |||||||||
|
O'Brien Patrick
· Officer
5 operations
-3K
|
O'Brien Patrick | Officer | 5 operations | – | -3K | – | 526K | – | Dec 31, 2025 | Jan 5, 2026 | |||||||||
|
Anzalone Christopher Richard
· Director, Officer
2 operations
−$3.6M
|
Anzalone Christopher Richard | Director, Officer | 2 operations | $68.69–$69.33 | −52K | −$3.6M | 3.8M | – | Dec 29, 2025 | Dec 30, 2025 | |||||||||
|
Anzalone Christopher Richard
· Director, Officer
4 operations
0
|
Anzalone Christopher Richard | Director, Officer | 4 operations | $6.15 | 0 | – | 17K | – | Dec 29, 2025 | Dec 30, 2025 | |||||||||
N
A
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A
A
434 reporting institutions disclosed ARWR 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.