James Healy - 04 May 2026 Form 4 Insider Report for Seaport Therapeutics, Inc. (SPTX)

Reporting relationship: Director
Issuer ticker: SPTX
Reported as of: 04 May 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 04 May 2026, 18:14:20 UTC
Prior SEC filing: 30 Apr 2026
Next SEC filing: 12 Jun 2026
Source filing: View source filing
Reporting owner signature: /s/ Lana Gladstein, Attorney-in-Fact

Key filing fact

James Healy filed Form 4 for Seaport Therapeutics, Inc. (SPTX) on 04 May 2026.

Key facts

This page summarizes James Healy's Form 4 filing for Seaport Therapeutics, Inc. (SPTX).
4 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 04 May 2026, 18:14.

Change

Previous filing in this sequence was filed on 30 Apr 2026.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001245624 Primary reporting owner

HEALY JAMES

Relationship: Director
Address: SEAPORT THERAPEUTICS, INC., 101 SEAPORT BLVD., FLOOR 12, BOSTON
Signature: /s/ Lana Gladstein, Attorney-in-Fact
Signature date: 04 May 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

SPTX transaction

Common Stock

Conversion of derivative security

Transaction value
Shares: +1,927,159
Change %
Price
Shares after: 1,927,159
Date: 04 May 2026
Ownership: By Sofinnova Venture Partners XI, L.P.
Footnotes: F1, F2

SPTX transaction

Common Stock

Conversion of derivative security

Transaction value
Shares: +804,379
Change %: +42%
Price
Shares after: 2,731,538
Date: 04 May 2026
Ownership: By Sofinnova Venture Partners XI, L.P.
Footnotes: F1, F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

SPTX transaction Derivative

Series A-2 Preferred Stock

Conversion of derivative security

Transaction value
Shares: -6,052,631
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 04 May 2026
Ownership: By Sofinnova Venture Partners XI, L.P.
Underlying class: Common Stock
Underlying amount: 1,927,159
Exercise price
Footnotes: F1, F2

SPTX transaction Derivative

Series B Preferred Stock

Conversion of derivative security

Transaction value
Shares: -2,526,315
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 04 May 2026
Ownership: By Sofinnova Venture Partners XI, L.P.
Underlying class: Common Stock
Underlying amount: 804,379
Exercise price
Footnotes: F1, F2

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 2 footnotes

Footnote F1

Each share of Series A-2 and Series B Preferred Stock (collectively, the "Preferred Stock") was convertible into Common Stock of the Issuer on a one-for-3.1407 basis at the option of the holder, and automatically converted upon the closing of the Issuer's initial public offering without payment of further consideration. The Preferred Stock had no expiration date.

Footnote F2

These shares are directly held by Sofinnova Venture Partners XI, L.P. ("SVP XI"). Sofinnova Management XI, L.P. ("SM XI LP") is the general partner of SVP XI, and Sofinnova Management XI, L.L.C. ("SM XI") is the general partner of SM XI LP. The Reporting Person is a managing member of SM XI and may be deemed to share voting and investment discretion with respect to securities directly held by SVP XI. The Reporting Person disclaims beneficial ownership of the securities directly held by SVP XI. This report shall not be construed as an admission that he is the beneficial owner of the securities reported herein for purposes of Section 16 of the Securities Exchange Act of 1934, as amended, or for any other purpose, except to the extent of his pecuniary interest therein, if any.