Millennium Management LLC
· Reduced
Change
−843K
Date
Q1 2026
OS
| Investor | Type | Est. change | Change | Δ Own | Date | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
Millennium Management LLC
· Reduced
Change
−843K
Date
Q1 2026
|
Millennium Management LLC | Reduced· Q1 2026 | – | −843K | – | Q1 2026 | |||||
|
Yorkville Advisors Global, LP
· New
Change
+635K
Date
Q1 2026
|
Yorkville Advisors Global, LP | New· Q1 2026 | – | +635K | – | Q1 2026 | |||||
|
Dimensional
· Reduced
Change
−438K
Date
Q1 2026
|
Dimensional | Reduced· Q1 2026 | – | −438K | – | Q1 2026 | |||||
|
UBS Group AG
· Reduced
Change
−437K
Date
Q1 2026
|
UBS Group AG | Reduced· Q1 2026 | – | −437K | – | Q1 2026 | |||||
|
Steamboat Capital Partners, LLC
· Exited
Change
−400K
Δ Own
−100.0%
Date
Q1 2026
|
Steamboat Capital Partners, LLC | Exited· Q1 2026 | – | −400K | −100.0% | Q1 2026 | |||||
|
Neuberger Berman Group LLC
· Added
Change
+377K
Date
Q1 2026
|
Neuberger Berman Group LLC | Added· Q1 2026 | – | +377K | – | Q1 2026 | |||||
|
Citadel Advisors LLC
· Reduced
Change
−338K
Δ Own
−86.0%
Date
Q1 2026
|
Citadel Advisors LLC | Reduced· Q1 2026 | – | −338K | −86.0% | Q1 2026 | |||||
|
D. E. Shaw & Co., Inc.
· Reduced
Change
−283K
Δ Own
−17.0%
Date
Q1 2026
|
D. E. Shaw & Co., Inc. | Reduced· Q1 2026 | – | −283K | −17.0% | Q1 2026 | |||||
|
Jane Street Group, LLC
· Reduced
Change
−232K
Date
Q1 2026
|
Jane Street Group, LLC | Reduced· Q1 2026 | – | −232K | – | Q1 2026 | |||||
|
Qube Research & Technologies Ltd
· Exited
Change
−217K
Δ Own
−100.0%
Date
Q1 2026
|
Qube Research & Technologies Ltd | Exited· Q1 2026 | – | −217K | −100.0% | Q1 2026 | |||||
|
Archon Capital Management LLC
· Added
Change
+174K
Date
Q1 2026
|
Archon Capital Management LLC | Added· Q1 2026 | – | +174K | – | Q1 2026 | |||||
|
Morgan Stanley
· Reduced
Change
−155K
Date
Q1 2026
|
Morgan Stanley | Reduced· Q1 2026 | – | −155K | – | Q1 2026 | |||||
|
Bridgeway Capital Management, LLC
· Reduced
Change
−153K
Date
Q1 2026
|
Bridgeway Capital Management, LLC | Reduced· Q1 2026 | – | −153K | – | Q1 2026 | |||||
|
Gagnon Securities LLC
· Added
Change
+145K
Date
Q1 2026
|
Gagnon Securities LLC | Added· Q1 2026 | – | +145K | – | Q1 2026 | |||||
|
Gsa Capital Partners LLP
· Added
Change
+138K
Date
Q1 2026
|
Gsa Capital Partners LLP | Added· Q1 2026 | – | +138K | – | Q1 2026 | |||||
| Insider | Title | Type | Price | Qty | Value | Owned | ΔOwn | Trade date | Filed date | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Boyd Steven Kyle
· Director
Grant (A)
$16K
|
Boyd Steven Kyle | Director | Grant (A) | $4.43 | 4K | $16K | 163K | +2.3% | Jun 26, 2026 | Jun 30, 2026 | |||||||||
|
McMahon Robert W.
· Director
Grant (A)
46K
|
McMahon Robert W. | Director | Grant (A) | – | 46K | – | 123K | – | Jun 3, 2026 | Jun 5, 2026 | |||||||||
|
Gagliano Nancy J.
· Director
Grant (A)
46K
|
Gagliano Nancy J. | Director | Grant (A) | – | 46K | – | 185K | – | Jun 3, 2026 | Jun 5, 2026 | |||||||||
|
Marmora Lelio
· Director
Grant (A)
46K
|
Marmora Lelio | Director | Grant (A) | – | 46K | – | 148K | – | Jun 3, 2026 | Jun 5, 2026 | |||||||||
|
Kenny John P.
· Director
Grant (A)
46K
|
Kenny John P. | Director | Grant (A) | – | 46K | – | 210K | – | Jun 3, 2026 | Jun 5, 2026 | |||||||||
|
Bertrand John D.
· Director
Grant (A)
46K
|
Bertrand John D. | Director | Grant (A) | – | 46K | – | 80K | – | Jun 3, 2026 | Jun 5, 2026 | |||||||||
|
Boyd Steven Kyle
· Director
Grant (A)
46K
|
Boyd Steven Kyle | Director | Grant (A) | – | 46K | – | 160K | – | Jun 3, 2026 | Jun 5, 2026 | |||||||||
|
Boyd Steven Kyle
· Director
Buy
+$75K
|
Boyd Steven Kyle | Director | Buy | $2.99 | +25K | +$75K | 113K | – | May 14, 2026 | May 14, 2026 | |||||||||
|
Boyd Steven Kyle
· Director
Buy
+$76K
|
Boyd Steven Kyle | Director | Buy | $3.02 | +25K | +$76K | 88K | – | May 13, 2026 | May 14, 2026 | |||||||||
|
Marmora Lelio
· Director
Tax withholding or exercise payment (F)
-$86K
|
Marmora Lelio | Director | Tax withholding or exercise payment (F) | $3.02 | -28K | -$86K | 102K | – | May 13, 2026 | May 14, 2026 | |||||||||
|
McMahon Robert W.
· Director
Tax withholding or exercise payment (F)
-$69K
|
McMahon Robert W. | Director | Tax withholding or exercise payment (F) | $3.02 | -23K | -$69K | 77K | – | May 13, 2026 | May 14, 2026 | |||||||||
|
Gagliano Nancy J.
· Director
Tax withholding or exercise payment (F)
-$64K
|
Gagliano Nancy J. | Director | Tax withholding or exercise payment (F) | $3.02 | -21K | -$64K | 139K | – | May 13, 2026 | May 14, 2026 | |||||||||
|
Boyd Steven Kyle
· Director
Buy
+$74K
|
Boyd Steven Kyle | Director | Buy | $2.98 | +25K | +$74K | 63K | – | May 12, 2026 | May 14, 2026 | |||||||||
|
Bertrand John D.
· Director
Grant (A)
34K
|
Bertrand John D. | Director | Grant (A) | – | 34K | – | 34K | – | May 12, 2026 | May 14, 2026 | |||||||||
|
Boyd Steven Kyle
· Director
Tax withholding or exercise payment (F)
-$4K
|
Boyd Steven Kyle | Director | Tax withholding or exercise payment (F) | $3.10 | -1K | -$4K | 38K | – | Mar 26, 2026 | Mar 30, 2026 | |||||||||
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125 reporting institutions disclosed OSUR 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.