SEAPORT THERAPEUTICS INC COMMON STOCK (SPTX)
Institutional ownership reported to the SEC as of Q2 2026, across 2 quarters.
Institutions report 37,475,514 shares against 53,530,550 outstanding. Shares only - option lines are excluded, which is why this can be compared with the company at all. The count comes from the cover page of the company's own most recent report, so it is dated when that was filed rather than at quarter end.
Calls and puts are the parts of reported value carried in derivative lines rather than shares, and they point in opposite directions: a manager holding calls is positioned for the security, one holding puts against it - or hedging shares they already own, which is why index funds carry so many. Most sites add the two together and report one figure, which averages away the only interesting part.
Holders
| Filer | Value | Shares | Their book | Held | Change |
|---|---|---|---|---|---|
| ARCH Venture Management, LLC | $136.6M | 6,294,951 | 12.42% | new | NEW |
| GENERAL ATLANTIC, L.P. | $132.5M | 6,101,582 | 4.56% | new | NEW |
| Sofinnova Investments, Inc. | $77.4M | 3,564,871 | 4.00% | new | NEW |
| GOLDMAN SACHS GROUP INC | $47.3M | 2,178,642 | 0.00% | new | NEW |
| TRV GP VI, LLC | $44.8M | 2,061,222 | 19.27% | new | NEW |
| CANADA PENSION PLAN INVESTMENT BOARD | $42.9M | 1,975,791 | 0.02% | new | NEW |
| JPMORGAN CHASE & CO | $40.9M | 1,815,845 | 0.00% | new | NEW |
| Foresite Capital Management VI LLC | $38.7M | 1,779,521 | 6.02% | new | NEW |
| PRICE T ROWE ASSOCIATES INC /MD/ | $28.4M | 1,308,604 | 0.00% | new | NEW |
| FMR LLC | $25.7M | 1,185,100 | 0.00% | new | NEW |
| Bellevue Group AG | $23.9M | 1,100,000 | 0.50% | new | NEW |
| Siren, L.L.C. | $23.8M | 1,095,316 | 0.48% | new | NEW |
| JENNISON ASSOCIATES LLC | $23.5M | 1,079,669 | 0.01% | new | NEW |
| RA CAPITAL MANAGEMENT, L.P. | $15.2M | 700,000 | 0.13% | new | NEW |
| VANGUARD CAPITAL MANAGEMENT LLC | $13.0M | 599,217 | 0.00% | new | NEW |
| Woodline Partners LP | $12.7M | 586,345 | 0.04% | new | NEW |
| PERCEPTIVE ADVISORS LLC | $10.9M | 500,000 | 0.16% | new | NEW |
| BRAIDWELL LP | $10.9M | 500,000 | 0.40% | new | NEW |
| PRINCIPAL FINANCIAL GROUP INC | $9.0M | 414,672 | 0.00% | new | NEW |
| Aberdeen Group plc | $6.7M | 310,355 | 0.01% | new | NEW |
| UBS Group AG | $6.1M | 279,184 | 0.00% | new | NEW |
| BlackRock, Inc. | $5.0M | 229,863 | 0.00% | new | NEW |
| SEVEN GRAND MANAGERS, LLC | $4.9M | 225,000 | 0.20% | new | NEW |
| CITADEL ADVISORS LLC | $4.2M | 191,144 | 0.00% | new | NEW |
| GEODE CAPITAL MANAGEMENT, LLC | $3.8M | 175,866 | 0.00% | new | NEW |
| Pier Capital, LLC | $3.7M | 169,985 | 0.49% | new | NEW |
| AMERIPRISE FINANCIAL INC | $2.9M | 131,788 | 0.00% | new | NEW |
| CHARLES SCHWAB INVESTMENT MANAGEMENT INC | $2.1M | 97,693 | 0.00% | new | NEW |
| VANGUARD FIDUCIARY TRUST CO | $1.9M | 87,772 | 0.00% | new | NEW |
| Pentwater Capital Management LP | $1.8M | 83,000 | 0.01% | new | NEW |
| MANUFACTURERS LIFE INSURANCE COMPANY, THE | $1.8M | 82,565 | 0.00% | new | NEW |
| Alyeska Investment Group, L.P. | $1.6M | 75,000 | 0.00% | new | NEW |
| STATE STREET CORP | $1.4M | 66,650 | 0.00% | new | NEW |
| ALPS ADVISORS INC | $1.2M | 54,328 | 0.01% | new | NEW |
| TD Asset Management Inc | $1.0M | 47,944 | 0.00% | new | NEW |
| MILLENNIUM MANAGEMENT LLC | $984.7K | 45,337 | 0.00% | new | NEW |
| GSA CAPITAL PARTNERS LLP | $721.0K | 33,178 | 0.05% | new | NEW |
| DAFNA Capital Management LLC | $703.7K | 32,400 | 0.13% | new | NEW |
| NORTHERN TRUST CORP | $690.7K | 31,802 | 0.00% | new | NEW |
| ADAR1 Capital Management, LLC | $564.7K | 26,000 | 0.03% | new | NEW |
| Ghisallo Capital Management LLC | $543.0K | 25,000 | 0.01% | new | NEW |
| Burkehill Global Management, LP | $543.0K | 25,000 | 0.02% | new | NEW |
| Squarepoint Ops LLC | $537.6K | 24,753 | 0.00% | new | NEW |
| HighTower Advisors, LLC | $362.0K | 16,666 | 0.00% | new | NEW |
| MORGAN STANLEY | $254.0K | 11,692 | 0.00% | new | NEW |
| XTX Topco Ltd | $238.6K | 10,983 | 0.00% | new | NEW |
| Weiss Asset Management LP | $217.2K | 10,000 | 0.00% | new | NEW |
| Zimmer Partners, LP | $217.2K | 10,000 | 0.01% | new | NEW |
| VANGUARD PORTFOLIO MANAGEMENT LLC | $197.2K | 9,081 | 0.00% | new | NEW |
| Vanguard Global Advisers, LLC | $155.5K | 7,159 | 0.00% | new | NEW |
| CITIGROUP INC | $53.3K | 2,454 | 0.00% | new | NEW |
| JONES FINANCIAL COMPANIES LLLP | $48.3K | 2,256 | 0.00% | new | NEW |
| ASSETMARK, INC | $31.1K | 1,431 | 0.00% | new | NEW |
| BARCLAYS PLC | $18.2K | 837 | 0.00% | new | NEW |
What the insiders did
Open market purchases and sales reported on Form 4 in the last 180 days. Grants, option exercises and shares surrendered to cover tax are left out: they are compensation rather than a decision to buy or sell. Where a broker filled one order in tranches the lines are summed, because it was one decision.
Officers and directors
| Date | Insider | Role | Side | Shares | Value |
|---|---|---|---|---|---|
| 2026-06-22 | HOMBACH ROBERT J. | Director | Bought | 13,000 | $235.8K |
Quarter by quarter
Coverage begins with the quarter ending 2018-12-31. Earlier filings exist only as occasional late amendments, too sparse to describe a market, so they are not shown.
| Quarter | Holders | Value | Shares | New | Added | Trimmed | Options |
|---|---|---|---|---|---|---|---|
| Q3 2026 | 3 | $50.3K | 2,492 | 2 | 1 | 0 | 0.0% |
| Q2 2026 | 54 | $815.3M | 37,475,514 | 54 | 0 | 0 | 0.0% |