Who owns Seaport Therapeutics, Inc.?
Prices and market caps: Cboe delayed data, at least 15 minutes delayed. Not real-time. Fundamentals from company filings.
Institutional ownership of SPTX from SEC Form 13F filings across 54 reporting managers. All positions are from one synchronized reporting period — 2026-06-30 books, filed up to 45 days after quarter end — so every row is comparable.
As of the 2026-06-30 reporting period, 54 institutions disclosed 37.5M shares of Seaport Therapeutics, Inc. worth $815.3M — about 106.4% of shares outstanding; the largest disclosed holder is ARCH Venture Management, LLC. Source: SEC Form 13F filings, parsed by EvidInvest.
54
13F holders
$815.3M
value, 2026 filers
106.4%
of shares outstanding (37.5M sh)
54
new positions (2026 filers)
Top institutional holders
ordered by shares owned · positions as of 2026-06-30 · % of fund = share of the manager's own book · % of co. = share of SPTX's shares outstanding
| # | Manager | Shares | Value | % of fund | % of co. | Δ shares QoQ |
|---|---|---|---|---|---|---|
| 1 | ARCH Venture Management, LLCNEW | 6.3M | $136.6M | 12.4% | 17.9% | new |
| 2 | GENERAL ATLANTIC, L.P.NEW | 6.1M | $132.5M | 4.6% | 17.3% | new |
| 3 | Sofinnova Investments, Inc.NEW | 3.6M | $77.4M | 4.0% | 10.1% | new |
| 4 | GOLDMAN SACHS GROUP INCNEW | 2.2M | $47.3M | 0.0% | 6.2% | new |
| 5 | TRV GP VI, LLCNEW | 2.1M | $44.8M | 19.3% | 5.8% | new |
| 6 | CANADA PENSION PLAN INVESTMENT BOARDNEW | 2.0M | $42.9M | 0.0% | 5.6% | new |
| 7 | JPMORGAN CHASE & CONEW | 1.8M | $40.9M | 0.0% | 5.2% | new |
| 8 | Foresite Capital Management VI LLCNEW | 1.8M | $38.7M | 6.0% | 5.1% | new |
| 9 | PRICE T ROWE ASSOCIATES INC /MD/NEW | 1.3M | $28.4M | 0.0% | 3.7% | new |
| 10 | FMR LLCNEW | 1.2M | $25.7M | 0.0% | 3.4% | new |
| 11 | Bellevue Group AGNEW | 1.1M | $23.9M | 0.5% | 3.1% | new |
| 12 | Siren, L.L.C.NEW | 1.1M | $23.8M | 0.5% | 3.1% | new |
| 13 | JENNISON ASSOCIATES LLCNEW | 1.1M | $23.5M | 0.0% | 3.1% | new |
| 14 | RA CAPITAL MANAGEMENT, L.P.NEW | 700,000 | $15.2M | 0.1% | 2% | new |
| 15 | VANGUARD CAPITAL MANAGEMENT LLCNEW | 599,217 | $13.0M | 0.0% | 1.7% | new |
| 16 | Woodline Partners LPNEW | 586,345 | $12.7M | 0.0% | 1.7% | new |
| 17 | BRAIDWELL LPNEW | 500,000 | $10.9M | 0.4% | 1.4% | new |
| 18 | PERCEPTIVE ADVISORS LLCNEW | 500,000 | $10.9M | 0.2% | 1.4% | new |
| 19 | PRINCIPAL FINANCIAL GROUP INCNEW | 414,672 | $9.0M | 0.0% | 1.2% | new |
| 20 | Aberdeen Group plcNEW | 310,355 | $6.7M | 0.0% | 0.9% | new |
| 21 | UBS Group AGNEW | 279,184 | $6.1M | 0.0% | 0.8% | new |
| 22 | BlackRock, Inc.NEW | 229,863 | $5.0M | 0.0% | 0.7% | new |
| 23 | SEVEN GRAND MANAGERS, LLCNEW | 225,000 | $4.9M | 0.2% | 0.6% | new |
| 24 | CITADEL ADVISORS LLCNEW | 191,144 | $4.2M | 0.0% | 0.5% | new |
| 25 | GEODE CAPITAL MANAGEMENT, LLCNEW | 175,866 | $3.8M | 0.0% | 0.5% | new |
Source: SEC Form 13F-HR filings (institutional managers over $100M in US-listed positions). 13Fs disclose long positions only, up to 45 days after quarter end; each manager's latest filed quarter is shown per row and dollar values are the manager's filed marks. Aggregates labeled "2026 filers" count only managers whose latest book is a 2026 quarter. Related: valuation · options positioning · supply chain. Research, not investment advice.