Woodline Partners LP
· Added
Change
+377K
Date
Q1 2026
XO
| Investor | Type | Est. change | Change | Δ Own | Date | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
Woodline Partners LP
· Added
Change
+377K
Date
Q1 2026
|
Woodline Partners LP | Added· Q1 2026 | – | +377K | – | Q1 2026 | |||||
|
Gw&k Investment Management, LLC
· New
Change
+232K
Date
Q1 2026
|
Gw&k Investment Management, LLC | New· Q1 2026 | – | +232K | – | Q1 2026 | |||||
|
Millennium Management LLC
· New
Change
+205K
Date
Q1 2026
|
Millennium Management LLC | New· Q1 2026 | – | +205K | – | Q1 2026 | |||||
|
FMR LLC
· Added
Change
+141K
Δ Own
+12.1%
Date
Q1 2026
|
FMR LLC | Added· Q1 2026 | – | +141K | +12.1% | Q1 2026 | |||||
|
Citadel Advisors LLC
· New
Change
+99K
Date
Q1 2026
|
Citadel Advisors LLC | New· Q1 2026 | – | +99K | – | Q1 2026 | |||||
|
Dimensional
· Added
Change
+90K
Date
Q1 2026
|
Dimensional | Added· Q1 2026 | – | +90K | – | Q1 2026 | |||||
|
Simcoe Capital LLC
· New
Change
+68K
Date
Q1 2026
|
Simcoe Capital LLC | New· Q1 2026 | – | +68K | – | Q1 2026 | |||||
|
Tls Advisors LLC
· Added
Change
+67K
Date
Q1 2026
|
Tls Advisors LLC | Added· Q1 2026 | – | +67K | – | Q1 2026 | |||||
|
Highvista Strategies LLC
· Reduced
Change
−66K
Date
Q1 2026
|
Highvista Strategies LLC | Reduced· Q1 2026 | – | −66K | – | Q1 2026 | |||||
|
UBS Group AG
· Added
Change
+46K
Date
Q1 2026
|
UBS Group AG | Added· Q1 2026 | – | +46K | – | Q1 2026 | |||||
|
Stonepine Capital Management, LLC
· Reduced
Change
−46K
Date
Q1 2026
|
Stonepine Capital Management, LLC | Reduced· Q1 2026 | – | −46K | – | Q1 2026 | |||||
|
Renaissance Technologies LLC
· Exited
Change
−39K
Δ Own
−100.0%
Date
Q1 2026
|
Renaissance Technologies LLC | Exited· Q1 2026 | – | −39K | −100.0% | Q1 2026 | |||||
|
Panagora Asset Management Inc
· Added
Change
+37K
Date
Q1 2026
|
Panagora Asset Management Inc | Added· Q1 2026 | – | +37K | – | Q1 2026 | |||||
|
BlackRock
· Added
Change
+35K
Date
Q1 2026
|
BlackRock | Added· Q1 2026 | – | +35K | – | Q1 2026 | |||||
|
Wellington Management Group LLP
· Exited
Change
−30K
Δ Own
−100.0%
Date
Q1 2026
|
Wellington Management Group LLP | Exited· Q1 2026 | – | −30K | −100.0% | Q1 2026 | |||||
| Insider | Title | Type | Price | Qty | Value | Owned | ΔOwn | Trade date | Filed date | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Bvf Partners L P
· 10% Owner
4 operations
-7.6M
|
Bvf Partners L P | 10% Owner | 4 operations | – | -7.6M | – | 0 | – | Jul 14, 2026 | Jul 16, 2026 | |||||||||
|
Montano Maricel Perea
· Officer
2 operations
-42K
|
Montano Maricel Perea | Officer | 2 operations | – | -42K | – | 0 | – | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Montano Maricel Perea
· Officer
2 operations
-48K
|
Montano Maricel Perea | Officer | 2 operations | – | -48K | – | 0 | – | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Limber Joseph M.
· Director
Other Form 4 events
-10K
|
Limber Joseph M. | Director | Other Form 4 events | – | -10K | – | 0 | −100.0% | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Limber Joseph M.
· Director
12 operations
-104K
|
Limber Joseph M. | Director | 12 operations | – | -104K | – | 0 | – | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Kosacz Barbara
· Director
Other Form 4 events
-6K
|
Kosacz Barbara | Director | Other Form 4 events | – | -6K | – | 0 | −100.0% | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Kosacz Barbara
· Director
7 operations
-69K
|
Kosacz Barbara | Director | 7 operations | – | -69K | – | 0 | – | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Wyszomierski Jack L.
· Director
Other Form 4 events
-22K
|
Wyszomierski Jack L. | Director | Other Form 4 events | – | -22K | – | 0 | −100.0% | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Wyszomierski Jack L.
· Director
8 operations
-55K
|
Wyszomierski Jack L. | Director | 8 operations | – | -55K | – | 0 | – | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Hughes Owen
· Director
2 operations
-192K
|
Hughes Owen | Director | 2 operations | – | -192K | – | 0 | – | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Hughes Owen
· Director
5 operations
-526K
|
Hughes Owen | Director | 5 operations | – | -526K | – | 0 | – | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Hernday Natasha
· Director
Other Form 4 events
-9K
|
Hernday Natasha | Director | Other Form 4 events | – | -9K | – | 0 | −100.0% | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Hernday Natasha
· Director
6 operations
-47K
|
Hernday Natasha | Director | 6 operations | – | -47K | – | 0 | – | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Sitko Bradley
· Officer
5 operations
-87K
|
Sitko Bradley | Officer | 5 operations | – | -87K | – | 0 | – | Jul 14, 2026 | Jul 14, 2026 | |||||||||
|
Sitko Bradley
· Officer
8 operations
-624K
|
Sitko Bradley | Officer | 8 operations | – | -624K | – | 0 | – | Jul 14, 2026 | Jul 14, 2026 | |||||||||
N
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70 reporting institutions disclosed XOMA 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.