Carl L. Gordon - 10 Aug 2026 Form 4 Insider Report for BlossomHill Therapeutics, Inc. (BLSM)

Reporting relationship: Director
Issuer ticker: BLSM
Reported as of: 10 Aug 2026
Net transaction value: $0
SEC form: 4
Accepted by SEC: 12 Aug 2026, 16:46:16 UTC
Prior SEC filing: 06 Aug 2026
Source filing: View source filing
Reporting owner signature: /s/ Carl L. Gordon

Key filing fact

Carl L. Gordon filed Form 4 for BlossomHill Therapeutics, Inc. (BLSM) on 12 Aug 2026.

Key facts

This page summarizes Carl L. Gordon's Form 4 filing for BlossomHill Therapeutics, Inc. (BLSM).
5 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 12 Aug 2026, 16:46.

Change

Previous filing in this sequence was filed on 06 Aug 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 0001282930 Primary reporting owner

GORDON CARL L

Relationship: Director
Address: C/O BLOSSOMHILL THERAPEUTICS, INC., 10255 SCIENCE CENTER DRIVE, SUITE 200, SAN DIEGO
Signature: /s/ Carl L. Gordon
Signature date: 12 Aug 2026

Reported non-derivative transactions

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

BLSM transaction

Common Stock

Conversion of derivative security

Transaction value
Shares: +1,039,996
Change %
Price
Shares after: 1,039,996
Date: 10 Aug 2026
Ownership: See footnotes
Footnotes: F1, F3, F4

BLSM transaction

Common Stock

Conversion of derivative security

Transaction value
Shares: +1,049,283
Change %: +101%
Price
Shares after: 2,089,279
Date: 10 Aug 2026
Ownership: See footnotes
Footnotes: F1, F3, F4

BLSM transaction

Common Stock

Purchase

Transaction value
Shares: +625,000
Change %: +30%
Price: $16.00^*
Shares after: 2,714,279
Date: 10 Aug 2026
Ownership: See footnotes
Footnotes: F2, F3, F4

Reported derivative securities

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

BLSM transaction Derivative

Series A Preferred Stock

Conversion of derivative security

Transaction value
Shares: -1,039,996
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 10 Aug 2026
Ownership: See footnotes
Underlying class: Common Stock
Underlying amount: 1,039,996
Exercise price
Footnotes: F1, F3, F4

BLSM transaction Derivative

Series B Preferred Stock

Conversion of derivative security

Transaction value
Shares: -1,049,283
Change %: -100%
Price: $0.000000^*
Shares after: 0
Date: 10 Aug 2026
Ownership: See footnotes
Underlying class: Common Stock
Underlying amount: 1,049,283
Exercise price
Footnotes: F1, F3, F4

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

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 4 footnotes

Footnote F1

Each share of Series A Preferred Stock and Series B Preferred Stock (together, the "Preferred Stock") automatically converted into 1 share of the Issuer's Common Stock upon the closing of the Issuer's initial public offering on August 10, 2026 without payment of consideration. The Preferred Stock has no expiration date.

Footnote F2

Reflects shares of the Issuer's Common Stock purchased in the Issuer's initial public offering.

Footnote F3

These securities are held directly by OrbiMed Private Investments VIII, LP ("OPI VIII"). OrbiMed Capital GP VIII LLC ("GP VIII") is the general partner of OPI VIII. OrbiMed Advisors LLC ("OrbiMed Advisors") is the managing member of GP VIII. By virtue of such relationships, GP VIII and OrbiMed Advisors may be deemed to have voting power and investment power over the securities held by OPI VIII and as a result, may be deemed to have beneficial ownership over such securities. OrbiMed Advisors exercises voting and investment power through a management committee comprised of the Reporting Person, W. Carter Neild, and Geoffrey C. Hsu, each of whom disclaims beneficial ownership of the shares held by OPI VIII.

Footnote F4

Each of the Reporting Person, OrbiMed Advisors, and GP VIII disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of its pecuniary interest therein, if any. This report shall not be deemed an admission that any of the Reporting Person, OrbiMed Advisors, or GP VIII is a beneficial owner of such securities for purposes of Section 16 of the Exchange Act, or for any other purpose.