Glaukos Corporation
Glaukos Corporation (GKOS) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · GKOS · as of Sep 30, 2025
Ownership Breakdown
327
Institutional Holders
▲ 16 vs Q2
$4.56B
Total Inst. Value
▼ $1.74B vs Q2
58.73M
Shares Outstanding
freeFloat 95.98%
55.93M
13F Shares Held
▼ 5.13M vs Q2
Institutional ownership = 13F shares ÷ total outstanding. Insider % = 100 − free float. Public % = free float − institution %. Data: FMP /symbol-positions-summary + /shares-float + SEC EDGAR.
Top Institutional Holders
GKOS largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
BLACKROCK, INC. surgical & medical instruments & apparatus | 8.66M | 15.21% | 15.21% | $705.88B | Nov 12, 2025 | ▼ 68.7K |
VANGUARD GROUP INC surgical & medical instruments & apparatus | 6.05M | 10.62% | 10.62% | $493.09B | Nov 7, 2025 | ▼ 65.7K |
WELLINGTON MANAGEMENT GROUP LLP surgical & medical instruments & apparatus | 3.58M | 6.29% | 6.29% | $292.00B | Nov 14, 2025 | ▲ 336.3K |
PRIMECAP MANAGEMENT CO/CA/ surgical & medical instruments & apparatus | 2.25M | 3.96% | 3.96% | $183.80B | Nov 12, 2025 | ▲ 425.8K |
STATE STREET CORP surgical & medical instruments & apparatus | 2.10M | 3.70% | 3.70% | $171.61B | Nov 14, 2025 | ▲ 14.0K |
AMERIPRISE FINANCIAL INC surgical & medical instruments & apparatus | 1.90M | 3.34% | 3.34% | $154.97B | Nov 14, 2025 | ▼ 99.0K |
ALLIANCEBERNSTEIN L.P. surgical & medical instruments & apparatus | 1.73M | 3.05% | 3.05% | $141.36B | Nov 14, 2025 | ▲ 481.6K |
GEODE CAPITAL MANAGEMENT, LLC surgical & medical instruments & apparatus | 1.32M | 2.31% | 2.31% | $107.34B | Nov 12, 2025 | ▼ 14.5K |
WESTFIELD CAPITAL MANAGEMENT CO LP surgical & medical instruments & apparatus | 1.23M | 2.16% | 2.16% | $100.44B | Nov 12, 2025 | ▲ 63.8K |
WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC surgical & medical instruments & apparatus | 1.09M | 1.92% | 1.92% | $89.19B | Nov 12, 2025 | ▼ 42.4K |
Data from SEC Form 13F filings. Ownership bar normalised to largest holder. Change flags: isNew / isSoldOut / changeInSharesNumber (FMP extract-analytics/holder).
Institutional Activity
Q3 2025 vs prior quarter
Q3 2025
24
Increased
+4.78M shares2
New Positions
first time holders22
Decreased
−2.56M shares0
Sold Out
fully exitedNet shares change (top 50)
+2.22M
+4.78M / −2.56M
Net new holders
+4
2 new / 0 exited
Based on top 50 institutional holders by position size. Fields: isNew, isSoldOut, changeInSharesNumber (FMP extract-analytics/holder, limit=50).
Insider Buying vs Selling
GKOS insider trading · insider activity
Source: SEC Form 4
Insiders have been primarily selling shares recently. Selling may be driven by pre-scheduled Rule 10b5-1 plans rather than negative sentiment.
5
Buy transactions
20
Sell transactions
0.25
Buy/Sell ratio
$0M
Total disposed
Recent Insider Transactions
Showing 10 most recent · Common Stock only
| Name · Role | Date | Type | Shares | Price | Value | After Trans. | Filing |
|---|---|---|---|---|---|---|---|
WEN LEANA director | May 28, 2026 | Award | 1,878 | — | — | 21.6K | Form 4 ↗ |
WEN LEANA director | May 28, 2026 | Award | 2,987 | $53.57 | $160.0K | 3.0K | Form 4 ↗ |
WEISNER AIMEE S director | May 28, 2026 | Award | 1,878 | — | — | 20.7K | Form 4 ↗ |
WEISNER AIMEE S director | May 28, 2026 | Award | 2,987 | $53.57 | $160.0K | 3.0K | Form 4 ↗ |
Torres Denice director | May 28, 2026 | Award | 1,878 | — | — | 24.2K | Form 4 ↗ |
Torres Denice director | May 28, 2026 | Award | 2,987 | $53.57 | $160.0K | 3.0K | Form 4 ↗ |
Foley Mark J director | May 28, 2026 | Award | 1,878 | — | — | 60.3K | Form 4 ↗ |
Foley Mark J director | May 28, 2026 | Award | 2,987 | $53.57 | $160.0K | 3.0K | Form 4 ↗ |
Hoffmeister David F director | May 28, 2026 | Award | 1,878 | — | — | 49.5K | Form 4 ↗ |
Hoffmeister David F director | May 28, 2026 | Award | 2,987 | $53.57 | $160.0K | 3.0K | Form 4 ↗ |
Source: /insider-trading/search (FMP stable). Buy/Sell direction: acquisitionOrDisposition A=Buy, D=Sell. RSU vesting (M-Exempt) excluded from sentiment bar. All data from SEC EDGAR public filings.
About institutional & insider ownership
Glaukos Corporation (GKOS) is primarily owned by institutional investors, who hold approximately 95.2% of total shares outstanding. Company insiders own approximately 4.02%, while retail and public investors account for the remaining 0.77%.
The largest institutional shareholder of Glaukos Corporation is BLACKROCK, INC., holding approximately 8.66 million shares — equal to 15.21% of outstanding shares — as of September 30, 2025.
A total of 327 institutional investors currently hold GKOS stock, with a combined institutional value of approximately $4.56 billion as of the most recent 13F filing period.
Frequently asked questions
GKOS ownershipGlaukos Corporation (GKOS) is primarily owned by institutional investors, who hold approximately 95.2% of shares. The largest shareholder is BLACKROCK, INC. with a 15.21% stake. Company insiders hold 4.02%. Data sourced from SEC Form 13F as of September 30, 2025.