Skip to content
Insider tapeFilings through Fri, Oct 9
Watchlist
SPTX

Seaport Therapeutics (SPTX) stock: insider trades, news & valuation

Net buying
Close · Oct 9, 2026 $18.15 +1.3% on the day -8.5% over 12 months 52-week range $15.25 – $27.84

Share price and insider trades

SPTX closeInsider buyInsider sale
15202530MayJunJulAugSepOctBought $235,820 on 2026-06-22 · Robert J. HombachBought $19,800,000 on 2026-05-04 · Arch Venture Partners Xii, L.P.
Bought, 12 months$20.0M
Sold, 12 months$0
Insiders buying2
Insiders selling0

Seaport Therapeutics insider trading at a glance (Oct 9, 2026): in the past 12 months, 2 insiders bought $20.0M and 0 sold $0 of SPTX stock on the open market.

SPTX insider buying and selling by quarter

Open-market purchases (green, above the line) and sales (red, below), by trade date.

Q2 2026: $20.0M bought (2 trades)$20.0MQ2 2026Q3 2026Q4 2026
QuarterBoughtPurchasesSoldSales
Q4 2026—0—0
Q3 2026—0—0
Q2 2026$20.0M2—0

Valuation, profit and volume

P/E (trailing)n/aSector median —
Market value— 
Profit margin—Revenue growth —
Volume vs. 50-day1.0×Last 5 sessions
Insiders' paper profit+$165KOn all tracked purchases +0.8%

Summary

Over the past 12 months, 2 Seaport Therapeutics, Inc. insiders reported open-market purchases totaling $20.0M, while 0 insiders reported sales totaling $0.

Insider transactions

Open-market purchases and sales.

Filed Insider Type Shares Price Value Since Score
Jun 24SEC Robert J. HombachDirector Buy 13,000new position $18.14 $236K +0.1% —
May 4SEC Arch Venture Partners Xii, L.P.10% Owner Buy 1,100,0006,294,951 held (+21%) $18.00 $19.8M +0.8% —

Insiders at Seaport Therapeutics, Inc.

InsiderBoughtSoldLast filingScore
Arch Venture Partners Xii, L.P.10% Owner $19.8M — May 4, 2026 —
Robert J. HombachDirector $236K — Jun 24, 2026 —

SPTX stock: common questions

Are Seaport Therapeutics, Inc. insiders buying SPTX stock?

In the past 12 months, 2 insiders reported open-market purchases of SPTX worth $20.0M. The latest was Director Robert J. Hombach bought $236K of SPTX at $18.14 — first open-market purchase in our records; opens a new position.

Are Seaport Therapeutics, Inc. insiders selling SPTX stock?

0 insiders reported sales worth $0 over the same period.

Where does this data come from?

Every transaction comes from Form 4 filings that insiders must submit to the SEC within two business days of a trade. We pull them from SEC EDGAR every night.

What is SPTX's 52-week range?

Over the past year SPTX has traded between $15.25 and $27.84. It last closed at $18.15 on Oct 9, 2026.