Seaport Therapeutics Ownership

Who are the major shareholders and have insiders been buying or selling?

Recent Insider Transactions

NasdaqGS:SPTX Recent Insider Transactions by Companies or Individuals
Date	Value	Name	Entity	Shares	Max Price
22 Jun 26	BuyUS$235,768	Robert Hombach	Individual	13,000	US$18.14
04 May 26	BuyUS$19,800,000	ARCH Venture Fund XII, L.P.	Company	1,100,000	US$18.00
01 May 26	BuyUS$19,800,000	ARCH Venture Fund XII, L.P.	Company	1,100,000	US$18.00

Insider Trading Volume

Insider Buying: SPTX insiders have bought more shares than they have sold in the past 3 months.

Ownership Breakdown

What is the ownership structure of SPTX?
Owner Type	Number of Shares	Ownership Percentage
Individual Insiders	2,449,595	4.33%
VC/PE Firms	15,961,404	28.2%
Public Companies	16,685,013	29.5%
Institutions	21,476,631	38%

Dilution of Shares: SPTX only recently listed within the past 12 months

Top Shareholders

Top 25 shareholders own 101.35% of the company

Ownership	Name	Shares	Current Value	Change %	Portfolio %
31.2%	PureTech Health plc	16,685,013	US$405.6m	0%	no data
11.8%	Arch Venture Partners, L.P.	6,294,951	US$153.0m	0%	7.67%
11.4%	General Atlantic Service Company, L.P.	6,101,582	US$148.3m	0%	3.27%
6.66%	Sofinnova Investments, Inc.	3,564,871	US$86.7m	0%	4.42%
3.85%	Third Rock Ventures, LLC	2,061,222	US$50.1m	0%	4.4%
3.69%	Canada Pension Plan Investment Board	1,975,791	US$48.0m	0%	0.02%
3.33%	JP Morgan Asset Management	1,785,104	US$43.4m	0%	no data
3.32%	Foresite Capital Management, LLC	1,779,521	US$43.3m	0%	2.87%
2.44%	T. Rowe Price Group, Inc.	1,308,604	US$31.8m	0%	no data
2.23%	The Goldman Sachs Group, Inc.	1,194,858	US$29.0m	0%	0.01%
2.23%	Daphne Zohar	1,194,001	US$29.0m	0%	no data
2.21%	FMR LLC	1,185,100	US$28.8m	0%	no data
2.05%	Bellevue Asset Management AG	1,100,000	US$26.7m	0%	0.43%
2.05%	Artal Group S.A.	1,095,316	US$26.6m	0%	0.38%
2.02%	Jennison Associates LLC	1,079,669	US$26.2m	0%	0.01%
1.84%	Goldman Sachs Asset Management, L.P.	983,784	US$23.9m	0%	no data
1.61%	Steven Paul	863,031	US$21.0m	0%	no data
1.31%	RA Capital Management, L.P.	700,000	US$17.0m	0%	0.14%
1.28%	Vanguard Capital Management, LLC	686,989	US$16.7m	0%	no data
1.1%	Woodline Partners LP	586,345	US$14.3m	0%	0.04%
0.93%	Perceptive Advisors LLC	500,000	US$12.2m	0%	0.18%
0.93%	Braidwell LP	500,000	US$12.2m	0%	0.41%
0.77%	Principal Global Investors, LLC	414,672	US$10.1m	0%	no data
0.58%	Aberdeen Group Plc	310,355	US$7.5m	0%	no data
0.57%	Eric Elenko	302,480	US$7.4m	0%	no data

Company Analysis and Financial Data Status

Data	Last Updated (UTC time)
Company Analysis	2026/08/24 15:33
End of Day Share Price	2026/08/21 00:00
Earnings	2026/06/30
Annual Earnings	2025/12/31

Data Sources

The data used in our company analysis is from S&P Global Market Intelligence LLC. The following data is used in our analysis model to generate this report. Data is normalised which can introduce a delay from the source being available.

Package	Data	Timeframe	Example US Source ^*
Company Financials	10 years	Income statement Cash flow statement Balance sheet	SEC Form 10-K SEC Form 10-Q
Analyst Consensus Estimates	+3 years	Forecast financials Analyst price targets	Analyst Research Reports Blue Matrix
Market Prices	30 years	Stock prices Dividends, Splits and Actions	ICE Market Data SEC Form S-1
Ownership	10 years	Top shareholders Insider trading	SEC Form 4 SEC Form 13D
Management	10 years	Leadership team Board of directors	SEC Form 10-K SEC Form DEF 14A
Key Developments	10 years	Company announcements	SEC Form 8-K

^* Example for US securities, for non-US equivalent regulatory forms and sources are used.

Unless specified all financial data is based on a yearly period but updated quarterly. This is known as Trailing Twelve Month (TTM) or Last Twelve Month (LTM) Data. Learn more.

Analysis Model and Snowflake

Details of the analysis model used to generate this report is available on our Github page, we also have guides on how to use our reports and tutorials on Youtube.

Learn about the world class team who designed and built the Simply Wall St analysis model.

Industry and Sector Metrics

Our industry and section metrics are calculated every 6 hours by Simply Wall St, details of our process are available on Github.

Analyst Sources

Seaport Therapeutics, Inc. is covered by 7 analysts. 5 of those analysts submitted the estimates of revenue or earnings used as inputs to our report. Analysts submissions are updated throughout the day.

Analyst	Institution
Yigal Nochomovitz	Citigroup Inc
Salveen Richter	Goldman Sachs
Raghuram Selvaraju	H.C. Wainwright & Co.