Divisadero Street Capital Management, LP
· Added
Change
+1.2M
Date
Q1 2026
AT
| Investor | Type | Est. change | Change | Δ Own | Date | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
Divisadero Street Capital Management, LP
· Added
Change
+1.2M
Date
Q1 2026
|
Divisadero Street Capital Management, LP | Added· Q1 2026 | – | +1.2M | – | Q1 2026 | |||||
|
Goldman Sachs Group Inc
· Added
Change
+782K
Date
Q1 2026
|
Goldman Sachs Group Inc | Added· Q1 2026 | – | +782K | – | Q1 2026 | |||||
|
Marshall Wace, LLP
· Added
Change
+554K
Date
Q1 2026
|
Marshall Wace, LLP | Added· Q1 2026 | – | +554K | – | Q1 2026 | |||||
|
Wellington Management Group LLP
· Reduced
Change
−535K
Δ Own
−13.7%
Date
Q1 2026
|
Wellington Management Group LLP | Reduced· Q1 2026 | – | −535K | −13.7% | Q1 2026 | |||||
|
First Light Asset Management, LLC
· Reduced
Change
−446K
Date
Q1 2026
|
First Light Asset Management, LLC | Reduced· Q1 2026 | – | −446K | – | Q1 2026 | |||||
|
Defilade Capital Management, L.P.
· Exited
Change
−398K
Δ Own
−100.0%
Date
Q1 2026
|
Defilade Capital Management, L.P. | Exited· Q1 2026 | – | −398K | −100.0% | Q1 2026 | |||||
|
Vanguard
· Added
Change
+377K
Date
Q1 2026
|
Vanguard | Added· Q1 2026 | – | +377K | – | Q1 2026 | |||||
|
Morgan Stanley
· Added
Change
+373K
Date
Q1 2026
|
Morgan Stanley | Added· Q1 2026 | – | +373K | – | Q1 2026 | |||||
|
Two Sigma Investments, LP
· Added
Change
+371K
Δ Own
+97.4%
Date
Q1 2026
|
Two Sigma Investments, LP | Added· Q1 2026 | – | +371K | +97.4% | Q1 2026 | |||||
|
Alliancebernstein L.P.
· Reduced
Change
−305K
Date
Q1 2026
|
Alliancebernstein L.P. | Reduced· Q1 2026 | – | −305K | – | Q1 2026 | |||||
|
Point72 Asset Management, L.P.
· Exited
Change
−278K
Δ Own
−100.0%
Date
Q1 2026
|
Point72 Asset Management, L.P. | Exited· Q1 2026 | – | −278K | −100.0% | Q1 2026 | |||||
|
Two Sigma Advisers, LP
· Exited
Change
−278K
Δ Own
−100.0%
Date
Q1 2026
|
Two Sigma Advisers, LP | Exited· Q1 2026 | – | −278K | −100.0% | Q1 2026 | |||||
|
Arrowstreet Capital, Limited Partnership
· New
Change
+278K
Date
Q1 2026
|
Arrowstreet Capital, Limited Partnership | New· Q1 2026 | – | +278K | – | Q1 2026 | |||||
|
Nomura Asset Management International Inc.
· Reduced
Change
−234K
Date
Q1 2026
|
Nomura Asset Management International Inc. | Reduced· Q1 2026 | – | −234K | – | Q1 2026 | |||||
|
Algert Global LLC
· Reduced
Change
−221K
Date
Q1 2026
|
Algert Global LLC | Reduced· Q1 2026 | – | −221K | – | Q1 2026 | |||||
| Insider | Title | Type | Price | Qty | Value | Owned | ΔOwn | Trade date | Filed date | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Carrel Michael H.
· Director
Grant (A)
$15K
|
Carrel Michael H. | Director | Grant (A) | $23.78 | 636 | $15K | 779K | +0.1% | Jun 30, 2026 | Jul 2, 2026 | |||||||||
|
Doraiswamy Vinayak
· Officer
Grant (A)
$15K
|
Doraiswamy Vinayak | Officer | Grant (A) | $23.78 | 636 | $15K | 93K | +0.7% | Jun 30, 2026 | Jul 2, 2026 | |||||||||
|
Dahlquist Karl S.
· Officer
Grant (A)
$15K
|
Dahlquist Karl S. | Officer | Grant (A) | $23.78 | 636 | $15K | 97K | +0.7% | Jun 30, 2026 | Jul 2, 2026 | |||||||||
|
Seith Douglas J.
· Officer
Grant (A)
$13K
|
Seith Douglas J. | Officer | Grant (A) | $23.78 | 527 | $13K | 230K | +0.2% | Jun 30, 2026 | Jul 2, 2026 | |||||||||
|
Privitera Salvatore
· Officer
Grant (A)
$15K
|
Privitera Salvatore | Officer | Grant (A) | $23.78 | 636 | $15K | 159K | +0.4% | Jun 30, 2026 | Jul 2, 2026 | |||||||||
|
Prange Karen
· Director
Sell
−$86K
|
Prange Karen | Director | Sell | $28.65 | −3K | −$86K | 26K | – | May 20, 2026 | May 22, 2026 | |||||||||
|
Prange Karen
· Director
Grant (A)
6K
|
Prange Karen | Director | Grant (A) | – | 6K | – | 29K | – | May 18, 2026 | May 20, 2026 | |||||||||
|
Telman Deborah H.
· Director
Grant (A)
6K
|
Telman Deborah H. | Director | Grant (A) | – | 6K | – | 28K | – | May 18, 2026 | May 20, 2026 | |||||||||
|
Yuen Maggie
· Director
Grant (A)
6K
|
Yuen Maggie | Director | Grant (A) | – | 6K | – | 18K | – | May 18, 2026 | May 20, 2026 | |||||||||
|
Nachman Shlomo
· Director
Grant (A)
6K
|
Nachman Shlomo | Director | Grant (A) | – | 6K | – | 25K | – | May 18, 2026 | May 20, 2026 | |||||||||
|
Johnson B. Kristine
· Director
Grant (A)
6K
|
Johnson B. Kristine | Director | Grant (A) | – | 6K | – | 56K | – | May 18, 2026 | May 20, 2026 | |||||||||
|
Groves Regina E.
· Director
Grant (A)
6K
|
Groves Regina E. | Director | Grant (A) | – | 6K | – | 40K | – | May 18, 2026 | May 20, 2026 | |||||||||
|
Wehrwein Sven
· Director
Grant (A)
6K
|
Wehrwein Sven | Director | Grant (A) | – | 6K | – | 41K | – | May 18, 2026 | May 20, 2026 | |||||||||
|
White Robert S.
· Director
Grant (A)
6K
|
White Robert S. | Director | Grant (A) | – | 6K | – | 128K | – | May 18, 2026 | May 20, 2026 | |||||||||
|
Doraiswamy Vinayak
· Officer
Sell
−$141K
|
Doraiswamy Vinayak | Officer | Sell | $28.13 | −5K | −$141K | 92K | – | May 15, 2026 | May 18, 2026 | |||||||||
N
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214 reporting institutions disclosed ATRC 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.