Phathom Pharmaceuticals, Inc.
Phathom Pharmaceuticals, Inc. (PHAT) Stock Ownership
Institutional vs insider vs public ownership from 13F and float data — top holders, activity, and insider trades below.
SEC 13F · FMP · PHAT · as of Sep 30, 2025
Ownership Breakdown
138
Institutional Holders
▲ 12 vs Q2
$733.76M
Total Inst. Value
▲ $183.15M vs Q2
79.76M
Shares Outstanding
freeFloat 71.32%
62.34M
13F Shares Held
▲ 4.93M 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
PHAT largest shareholders · institutional ownership
Q3 2025 · SEC 13F
Showing top 10 holders
| Holder | Shares | % Owned | Weight | Value | Reported | Change |
|---|---|---|---|---|---|---|
FRAZIER LIFE SCIENCES MANAGEMENT, L.P. pharmaceutical preparations | 12.47M | 17.20% | 17.20% | $146.73B | Nov 14, 2025 | — held |
MEDICXI VENTURES MANAGEMENT (JERSEY) LTD pharmaceutical preparations | 7.46M | 10.30% | 10.30% | $87.86B | Oct 17, 2025 | — held |
MILLENNIUM MANAGEMENT LLC pharmaceutical preparations | 5.08M | 7.01% | 7.01% | $59.81B | Nov 14, 2025 | ▲ 2.83M |
INVESCO LTD. pharmaceutical preparations | 3.86M | 5.33% | 5.33% | $45.49B | Nov 13, 2025 | ▼ 275.1K |
CARLYLE GROUP INC. pharmaceutical preparations | 3.50M | 4.83% | 4.83% | $41.05B | Nov 7, 2025 | — held |
BLACKROCK, INC. pharmaceutical preparations | 3.40M | 4.70% | 4.70% | $40.05B | Nov 12, 2025 | ▲ 87.0K |
VANGUARD GROUP INC pharmaceutical preparations | 3.22M | 4.44% | 4.44% | $37.85B | Nov 7, 2025 | ▲ 428.3K |
ENSIGN PEAK ADVISORS, INC pharmaceutical preparations | 2.50M | 3.45% | 3.45% | $29.46B | Nov 13, 2025 | ▼ 16.6K |
NEA MANAGEMENT COMPANY, LLC pharmaceutical preparations | 1.96M | 2.70% | 2.70% | $23.07B | Nov 14, 2025 | — held |
683 CAPITAL MANAGEMENT, LLC pharmaceutical preparations | 1.82M | 2.51% | 2.51% | $21.43B | Nov 14, 2025 | ▼ 284.6K |
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
25
Increased
+6.74M shares5
New Positions
first time holders10
Decreased
−2.03M shares0
Sold Out
fully exitedNet shares change (top 50)
+4.71M
+6.74M / −2.03M
Net new holders
+20
5 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
PHAT insider trading · insider activity
Source: SEC Form 4
8
Buy transactions
1
Sell transactions
8.00
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 |
|---|---|---|---|---|---|---|---|
Parikh Asit director | May 22, 2026 | Gift | 28,000 | — | — | 148.5K | Form 4 ↗ |
Parikh Asit director | May 22, 2026 | Gift | 28,000 | — | — | 24.1K | Form 4 ↗ |
Parikh Asit director | May 19, 2026 | Award | 24,122 | — | — | 34.6K | Form 4 ↗ |
Parikh Asit director | May 20, 2026 | D-Return | 17,500 | $4.95 | $86.6K | 0 | Form 4 ↗ |
Topper James N
| May 19, 2026 | Award | 24,122 | — | — | 66.7K | Form 4 ↗ |
Stenhouse Mark director | May 19, 2026 | Award | 24,122 | — | — | 54.1K | Form 4 ↗ |
FIELDS HEIDI director | May 19, 2026 | Award | 24,122 | — | — | 54.1K | Form 4 ↗ |
COLA MICHAEL F director | May 19, 2026 | Award | 24,122 | — | — | 63.9K | Form 4 ↗ |
KARBE FRANK director | May 19, 2026 | Award | 24,122 | — | — | 91.6K | Form 4 ↗ |
Schroeder Theodore R director | May 19, 2026 | Award | 24,122 | — | — | 45.1K | 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
Phathom Pharmaceuticals, Inc. (PHAT) is primarily owned by institutional investors, who hold approximately 78.2% of total shares outstanding. Company insiders own approximately 28.68%, while retail and public investors account for the remaining 0.00%.
The largest institutional shareholder of Phathom Pharmaceuticals, Inc. is FRAZIER LIFE SCIENCES MANAGEMENT, L.P., holding approximately 12.47 million shares — equal to 17.20% of outstanding shares — as of September 30, 2025.
A total of 138 institutional investors currently hold PHAT stock, with a combined institutional value of approximately $733,764,577 as of the most recent 13F filing period.
Frequently asked questions
PHAT ownershipPhathom Pharmaceuticals, Inc. (PHAT) is primarily owned by institutional investors, who hold approximately 78.2% of shares. The largest shareholder is FRAZIER LIFE SCIENCES MANAGEMENT, L.P. with a 17.20% stake. Company insiders hold 28.68%. Data sourced from SEC Form 13F as of September 30, 2025.