Janus Henderson Group PLC
· Added
+$262M
Change
+2.3M
Date
Q1 2026
GK
| Investor | Type | Est. change | Change | Δ Own | Date | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
Janus Henderson Group PLC
· Added
+$262M
Change
+2.3M
Date
Q1 2026
|
Janus Henderson Group PLC | Added· Q1 2026 | +$262M | +2.3M | – | Q1 2026 | |||||
|
Citadel Advisors LLC
· Added
+$160M
Change
+1.4M
Δ Own
+5267.7%
Date
Q1 2026
|
Citadel Advisors LLC | Added· Q1 2026 | +$160M | +1.4M | +5267.7% | Q1 2026 | |||||
|
Norges
· Exited
−$60M
Change
−536K
Δ Own
−100.0%
Date
Q1 2026
|
Norges | Exited· Q1 2026 | −$60M | −536K | −100.0% | Q1 2026 | |||||
|
Ameriprise Financial Inc
· Reduced
−$56M
Change
−494K
Date
Q1 2026
|
Ameriprise Financial Inc | Reduced· Q1 2026 | −$56M | −494K | – | Q1 2026 | |||||
|
Driehaus Capital Management LLC
· New
+$55M
Change
+488K
Date
Q1 2026
|
Driehaus Capital Management LLC | New· Q1 2026 | +$55M | +488K | – | Q1 2026 | |||||
|
UBS Group AG
· Reduced
−$55M
Change
−488K
Date
Q1 2026
|
UBS Group AG | Reduced· Q1 2026 | −$55M | −488K | – | Q1 2026 | |||||
|
Jennison Associates LLC
· New
+$55M
Change
+487K
Date
Q1 2026
|
Jennison Associates LLC | New· Q1 2026 | +$55M | +487K | – | Q1 2026 | |||||
|
Westfield Capital Management Co LP
· New
+$54M
Change
+482K
Date
Q1 2026
|
Westfield Capital Management Co LP | New· Q1 2026 | +$54M | +482K | – | Q1 2026 | |||||
|
Millennium Management LLC
· Reduced
−$49M
Change
−436K
Date
Q1 2026
|
Millennium Management LLC | Reduced· Q1 2026 | −$49M | −436K | – | Q1 2026 | |||||
|
Wellington Management Group LLP
· Reduced
−$38M
Change
−338K
Δ Own
−69.4%
Date
Q1 2026
|
Wellington Management Group LLP | Reduced· Q1 2026 | −$38M | −338K | −69.4% | Q1 2026 | |||||
|
Australiansuper Pty Ltd
· Reduced
−$36M
Change
−318K
Date
Q1 2026
|
Australiansuper Pty Ltd | Reduced· Q1 2026 | −$36M | −318K | – | Q1 2026 | |||||
|
D. E. Shaw & Co., Inc.
· Reduced
−$35M
Change
−307K
Δ Own
−55.0%
Date
Q1 2026
|
D. E. Shaw & Co., Inc. | Reduced· Q1 2026 | −$35M | −307K | −55.0% | Q1 2026 | |||||
|
FMR LLC
· Added
+$33M
Change
+293K
Δ Own
+2907.7%
Date
Q1 2026
|
FMR LLC | Added· Q1 2026 | +$33M | +293K | +2907.7% | Q1 2026 | |||||
|
Sofinnova Investments, Inc.
· Exited
−$32M
Change
−288K
Δ Own
−100.0%
Date
Q1 2026
|
Sofinnova Investments, Inc. | Exited· Q1 2026 | −$32M | −288K | −100.0% | Q1 2026 | |||||
|
Alliancebernstein L.P.
· Reduced
−$28M
Change
−246K
Date
Q1 2026
|
Alliancebernstein L.P. | Reduced· Q1 2026 | −$28M | −246K | – | Q1 2026 | |||||
| Insider | Title | Type | Price | Qty | Value | Owned | ΔOwn | Trade date | Filed date | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
|
Thurman Alex R.
· Officer
Sell
−$1.6M
|
Thurman Alex R. | Officer | Sell | $160.00 | −10K | −$1.6M | 44K | −18.6% | Jul 16, 2026 | Jul 21, 2026 | |||||||||
|
Thurman Alex R.
· Officer
2 operations
0
|
Thurman Alex R. | Officer | 2 operations | $38.68 | 0 | – | 10K | – | Jul 16, 2026 | Jul 21, 2026 | |||||||||
|
Thurman Alex R.
· Officer
Sell
−$1.6M
|
Thurman Alex R. | Officer | Sell | $155.00 | −10K | −$1.6M | 44K | −18.6% | Jul 9, 2026 | Jul 13, 2026 | |||||||||
|
Thurman Alex R.
· Officer
2 operations
0
|
Thurman Alex R. | Officer | 2 operations | $38.68 | 0 | – | 10K | – | Jul 9, 2026 | Jul 13, 2026 | |||||||||
|
Thurman Alex R.
· Officer
Sell
−$1.5M
|
Thurman Alex R. | Officer | Sell | $150.00 | −10K | −$1.5M | 44K | −18.6% | Jul 6, 2026 | Jul 8, 2026 | |||||||||
|
Thurman Alex R.
· Officer
2 operations
$0
|
Thurman Alex R. | Officer | 2 operations | $38.68 | 0 | $0 | 20K | – | Jul 6, 2026 | Jul 8, 2026 | |||||||||
|
Navratil Tomas
· Officer
Sell
−$100K
|
Navratil Tomas | Officer | Sell | $139.06 | −716 | −$100K | 88K | −0.8% | Jul 1, 2026 | Jul 8, 2026 | |||||||||
|
Burns Thomas William
· Director
Tax withholding or exercise payment (F)
-$579K
|
Burns Thomas William | Director | Tax withholding or exercise payment (F) | $142.57 | -4K | -$579K | 69K | −5.6% | Jun 25, 2026 | Jun 29, 2026 | |||||||||
|
Gilliam Joseph E.
· Officer
Tax withholding or exercise payment (F)
-$151K
|
Gilliam Joseph E. | Officer | Tax withholding or exercise payment (F) | $142.57 | -1K | -$151K | 72K | −1.4% | Jun 25, 2026 | Jun 29, 2026 | |||||||||
|
Navratil Tomas
· Officer
Tax withholding or exercise payment (F)
-$69K
|
Navratil Tomas | Officer | Tax withholding or exercise payment (F) | $142.57 | -483 | -$69K | 88K | −0.5% | Jun 25, 2026 | Jun 29, 2026 | |||||||||
|
Navratil Tomas
· Officer
Sell
−$201K
|
Navratil Tomas | Officer | Sell | $130.68 | −2K | −$201K | 89K | – | Jun 16, 2026 | Jun 18, 2026 | |||||||||
|
Wen Leana
· Director
2 operations
5K
|
Wen Leana | Director | 2 operations | – | 5K | – | 3K | – | May 28, 2026 | Jun 1, 2026 | |||||||||
|
Weisner Aimee S.
· Director
2 operations
5K
|
Weisner Aimee S. | Director | 2 operations | – | 5K | – | 3K | – | May 28, 2026 | Jun 1, 2026 | |||||||||
|
Torres Denice
· Director
2 operations
5K
|
Torres Denice | Director | 2 operations | – | 5K | – | 3K | – | May 28, 2026 | Jun 1, 2026 | |||||||||
|
Foley Mark J.
· Director
2 operations
5K
|
Foley Mark J. | Director | 2 operations | – | 5K | – | 3K | – | May 28, 2026 | Jun 1, 2026 | |||||||||
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318 reporting institutions disclosed GKOS 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.