SPTXNasdaqPharmaceutical PreparationsFiscal year ends December 31
Seaport Therapeutics, Inc.
Financials through Q2 FY2026, quarter ended Jun 30, 2026Last filing: 10-Q on Aug 3, 2026
$17.79−0.04 (-0.22%)
Close on Oct 19, 2026
- Market cap
- $626.85M
- P/E (TTM)
- –
- Dividend yield
- –
Ownership
Institutional holdings as of Jun 30, 2026, from 13F filings
Held by institutions
69.9%
37M of 54M shares
Institutional holders
54
54 new, 0 sold out
Net institutional buying
37M
In Q2 2026
Insider trades, 12 months
2 buys · 0 sales
Net bought $20.04M
Holders of more than 5%
Latest Schedule 13D (active) or 13G (passive) filed by each holder
| Holder | Shares | % of class | Filing | As of |
|---|---|---|---|---|
| ARCH Venture Fund XII, L.P. | 6,294,951 | 11.90% | 13D (active) | May 4, 2026 |
| General Atlantic (Lux) S.a r.l. | 6,101,582 | 11.50% | 13D (active) | May 4, 2026 |
| Zohar Daphne | 5,225,497 | 9.10% | 13G (passive) | Jun 30, 2026 |
| Paul Steven M | 3,516,718 | 6.30% | 13G (passive) | Jun 30, 2026 |
| Goldman Sachs & Co. LLC | 2,791,814 | 5.50% | 13G (passive) | May 6, 2026 |
| PureTech Health plc | 16,685,013 | 31.20% | 13G (passive) | Jun 30, 2026 |
Top institutional holders
13F holdings as of Jun 30, 2026
| Holder | Shares | % of SPTX | Value | Change | % of portfolio |
|---|---|---|---|---|---|
| ARCH Venture Management, LLC | 6,294,951 | 11.76% | $136.60M | New | 12.42% |
| General Atlantic, L.P. | 6,101,582 | 11.40% | $132.53M | New | 4.56% |
| Sofinnova Investments, Inc. | 3,564,871 | 6.66% | $77.43M | New | 4.00% |
| Goldman Sachs Group Inc | 2,178,642 | 4.07% | $47.32M | New | 0.00% |
| Trv Gp Vi, LLC | 2,061,222 | 3.85% | $44.77M | New | 19.27% |
| Canada Pension Plan Investment Board | 1,975,791 | 3.69% | $42.91M | New | 0.02% |
| JPMorgan Chase & Co | 1,815,845 | 3.39% | $40.89M | New | 0.00% |
| Foresite Capital Management VI LLC | 1,779,521 | 3.32% | $38.65M | New | 6.02% |
| Price T Rowe Associates Inc /Md/ | 1,308,604 | 2.44% | $28.42K | New | 0.00% |
| FMR LLC | 1,185,100 | 2.21% | $25.74M | New | 0.00% |
| Bellevue Group AG | 1,100,000 | 2.05% | $23.89M | New | 0.50% |
| Siren, L.L.C. | 1,095,316 | 2.05% | $23.79M | New | 0.48% |
| Jennison Associates LLC | 1,079,669 | 2.02% | $23.45M | New | 0.01% |
| Ra Capital Management, L.P. | 700,000 | 1.31% | $15.20M | New | 0.13% |
| Vanguard Capital Management LLC | 599,217 | 1.12% | $13.01M | New | 0.00% |
| Woodline Partners LP | 586,345 | 1.10% | $12.74M | New | 0.04% |
| Braidwell LP | 500,000 | 0.93% | $10.86M | New | 0.40% |
| Perceptive Advisors LLC | 500,000 | 0.93% | $10.86M | New | 0.16% |
| Principal Financial Group Inc | 414,672 | 0.77% | $9.01M | New | 0.00% |
| abrdn plc | 310,355 | 0.58% | $6.74M | New | 0.01% |
Institutional buying and selling by quarter
Positions opened, added to, reduced and closed by 13F filers
| Quarter | Holders | Shares held | % of shares | New / added | Reduced / closed | Shares bought | Shares sold |
|---|---|---|---|---|---|---|---|
| Q2 2026 | 54 | 37M | 69.9% | 54 / 0 | 0 / 0 | 37M | 0M |
Top mutual fund and ETF holders
Latest monthly portfolio reports (Form N-PORT)
| Fund | Shares | % of SPTX | Value | % of fund | As of |
|---|---|---|---|---|---|
| JPMorgan Small Cap Growth Fund | 840,931 | 1.57% | $18.27M | 0.70% | Jun 30, 2026 |
| PGIM Jennison Health Sciences Fund | 438,754 | 0.82% | $7.98M | 0.57% | May 29, 2026 |
| Vanguard Total Stock Market Index Fund | 426,371 | 0.80% | $9.26M | 0.00% | Jun 30, 2026 |
| T. Rowe Price Health Sciences Fund, Inc. | 299,319 | 0.56% | $6.50M | 0.05% | Jun 30, 2026 |
| JPMorgan Small Cap Blend Fund | 271,499 | 0.51% | $5.90M | 0.35% | Jun 30, 2026 |
| Fidelity Blue Chip Growth Fund | 235,900 | 0.44% | $4.83M | 0.00% | Jul 31, 2026 |
| Fidelity Growth Company Fund | 224,400 | 0.42% | $4.08M | 0.00% | May 31, 2026 |
| SmallCap Fund | 181,500 | 0.34% | $3.71M | 0.18% | Jul 31, 2026 |
| Vanguard Extended Market Index Fund | 165,436 | 0.31% | $3.59M | 0.00% | Jun 30, 2026 |
| Multi-Manager Small Cap Equity Strategies Fund | 107,880 | 0.20% | $1.96M | 0.15% | May 31, 2026 |
| Fidelity Growth Company K6 Fund | 62,296 | 0.12% | $1.13M | 0.00% | May 31, 2026 |
| Fidelity Series Growth Company Fund | 55,900 | 0.10% | $1.02M | 0.00% | May 31, 2026 |
| Fidelity Blue Chip Growth K6 Fund | 48,109 | 0.09% | $984.31K | 0.00% | Jul 31, 2026 |
| Fidelity Series Blue Chip Growth Fund | 43,700 | 0.08% | $894.10K | 0.01% | Jul 31, 2026 |
| Blackstone Alternative Multi-Strategy Fund | 29,589 | 0.06% | $642.67K | 0.02% | Jun 30, 2026 |
Officers, directors and major owners
People who filed Forms 3, 4 or 5 in the last two years
| Name | Role | Shares owned | % of shares | Latest filing |
|---|---|---|---|---|
| Daphne Zohar | Chief Executive Officer, Director | 1,194,001 | 2.23% | May 4, 2026 |
| Lana Gladstein | General Counsel | 33,515 | 0.06% | May 4, 2026 |
| Michael Cunyuan Chen | Chief Scientific Officer | 3,351 | 0.01% | May 4, 2026 |
| Lauren White | Chief Financial Officer | 6,702 | 0.01% | May 4, 2026 |
| Antony Loebel | Chief Medical Officer | 20,109 | 0.04% | May 4, 2026 |
| Robert J. Hombach | Director | 13,000 | 0.02% | Jun 24, 2026 |
| General Atlantic (SP), L.P. | Director, 10% owner | – | – | May 6, 2026 |
| Gap Coinvestments Iii, Llc | Director, 10% owner | – | – | May 6, 2026 |
| General Atlantic, L.P. | Director, 10% owner | – | – | May 6, 2026 |
| GAP Coinvestments CDA, L.P. | Director, 10% owner | – | – | May 6, 2026 |
| Gap Coinvestments Iv, Llc | Director, 10% owner | – | – | May 6, 2026 |
| (Bermuda) L.P. GAP | Director, 10% owner | – | – | May 6, 2026 |
| General Atlantic Genpar (Bermuda), L.P. | Director, 10% owner | – | – | May 6, 2026 |
| General Atlantic Genpar, L.P. | Director, 10% owner | – | – | May 6, 2026 |
| GAP Coinvestments V, LLC | Director, 10% owner | – | – | May 6, 2026 |
| General Atlantic (SPV) GP, LLC | Director, 10% owner | 6,101,582 | 11.40% | May 6, 2026 |
| Atlantic GenPar (Lux) SCSp General | Director, 10% owner | 6,101,582 | 11.40% | May 6, 2026 |
| General Atlantic Partners (Lux), SCSp | Director, 10% owner | – | – | May 6, 2026 |
| General Atlantic Partners 100, L.P. | Director, 10% owner | – | – | May 6, 2026 |
| Atlantic (Lux) S.a r.l. General | Director, 10% owner | – | – | May 6, 2026 |
| David E. Wheadon | Director | – | – | May 4, 2026 |
| Denice Torres | Director | 13,406 | 0.03% | May 4, 2026 |
| Sandra E. Peterson | Director | – | – | May 4, 2026 |
| Steven M. Paul | Director | 863,031 | 1.61% | May 4, 2026 |
| Sharon Mates | Director | – | – | May 4, 2026 |
| James Healy | Director | 1,927,159 | 3.60% | May 4, 2026 |
| Jason Pitts | Director | – | – | Apr 30, 2026 |
| PureTech LYT, Inc. | 10% owner | – | – | May 6, 2026 |
| Health plc PureTech | 10% owner | 13,038,493 | 24.36% | May 6, 2026 |
| ARCH Venture Partners XII, LLC | 10% owner | – | – | May 4, 2026 |
Insider trades
Common stock transactions reported on Form 4, newest first
| Insider | Date | Transaction | Shares | Price | Value | Shares after |
|---|---|---|---|---|---|---|
| Robert J. Hombach Director | Jun 22, 2026 | Buy | +13,000 | $18.14 | $235.82K | 13,000 |
| Health plc PureTech 10% owner | May 4, 2026 | Conversion | +12,736,014 | – | – | 13,038,493 |
| Health plc PureTech 10% owner | May 4, 2026 | Conversion | +965,255 | – | – | 16,685,013 |
| Health plc PureTech 10% owner | May 4, 2026 | Conversion | +2,681,265 | – | – | 15,719,758 |
| Michael Cunyuan Chen Chief Scientific Officer | May 4, 2026 | Conversion | +3,351 | – | – | 3,351 |
| Lana Gladstein General Counsel | May 4, 2026 | Conversion | +33,515 | – | – | 33,515 |
| Antony Loebel Chief Medical Officer | May 4, 2026 | Conversion | +20,109 | – | – | 20,109 |
| Lauren White Chief Financial Officer | May 4, 2026 | Conversion | +6,702 | – | – | 6,702 |
| Steven M. Paul Director | May 4, 2026 | Conversion | +67,031 | – | – | 863,031 |
| ARCH Venture Partners XII, L.P. 10% owner | May 4, 2026 | Conversion | +2,513,686 | – | – | 2,513,686 |
| ARCH Venture Partners XII, L.P. 10% owner | May 4, 2026 | Conversion | +2,681,265 | – | – | 5,194,951 |
| ARCH Venture Partners XII, L.P. 10% owner | May 4, 2026 | Buy | +1,100,000 | $18.00 | $19.80M | 6,294,951 |
| James Healy Director | May 4, 2026 | Conversion | +1,927,159 | – | – | 1,927,159 |
| James Healy Director | May 4, 2026 | Conversion | +804,379 | – | – | 2,731,538 |
| Denice Torres Director | May 4, 2026 | Conversion | +13,406 | – | – | 13,406 |
Awards, option exercises, tax withholding and gifts are shown alongside open-market buys and sales. Each name links to the filing on SEC EDGAR.