FRANK MCCORMICK - 26 Aug 2025 Form 4 Insider Report for BridgeBio Oncology Therapeutics, Inc. (HLXB)

Role: Director
Signature: /s/ Aaron Chan, Attorney-in-Fact
Issuer symbol: HLXB
Transactions as of: 26 Aug 2025
Net transactions value: $0
Form type: 4
Filing time: 28 Aug 2025, 16:43:27 UTC
Previous filing: 18 Aug 2025
Next filing: 08 Sep 2025
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
MCCORMICK FRANK	Director	BRIDGEBIO ONCOLOGY THERAPEUTICS, INC., 256 EAST GRAND AVENUE, SUITE 104, SOUTH SAN FRANCISCO	/s/ Aaron Chan, Attorney-in-Fact	28 Aug 2025	0001257809

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	BBOT	Stock Option (Right to Buy)	Award	$0	+91,076		$0.000000	91,076	26 Aug 2025	Common Stock	91,076	$9.59	Direct	F1

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	A fraction of the shares underlying such option equal to (x) the number of full months between August 11, 2025 ("Vesting Commencement Date") and the date on which a registration statement on Form S-8 is filed and effective with the Securities and Exchange Commission (the "S-8 Filing Date") divided by (y) 48 shall vest on the S-8 Filing Date, and 1/48th of the shares underlying such option shall vest each month thereafter on the day of the month corresponding to the Vesting Commencement Date (and if there is no suchcorresponding day for a month, then the vesting date shall be the last day of the applicable month) until 100% of the shares underlying such option is vested on the fourth anniversary of the Vesting Commencement Date, subject to the Reporting Person's continuous service the Issuer on each such vesting date.

Content

A fraction of the shares underlying such option equal to (x) the number of full months between August 11, 2025 ("Vesting Commencement Date") and the date on which a registration statement on Form S-8 is filed and effective with the Securities and Exchange Commission (the "S-8 Filing Date") divided by (y) 48 shall vest on the S-8 Filing Date, and 1/48th of the shares underlying such option shall vest each month thereafter on the day of the month corresponding to the Vesting Commencement Date (and if there is no suchcorresponding day for a month, then the vesting date shall be the last day of the applicable month) until 100% of the shares underlying such option is vested on the fourth anniversary of the Vesting Commencement Date, subject to the Reporting Person's continuous service the Issuer on each such vesting date.