Sec Form 4 Filing - MCCORMICK FRANK @ BridgeBio Oncology Therapeutics, Inc. - 2025-08-26

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person MCCORMICK FRANK 2. Issuer Name and Ticker or Trading Symbol BridgeBio Oncology Therapeutics, Inc. [ BBOT] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) BRIDGEBIO ONCOLOGY THERAPEUTICS, INC., 256 EAST GRAND AVENUE, SUITE 104 3. Date of Earliest Transaction (MM/DD/YY) 08/26/2025 (Street) SOUTH SAN FRANCISCO, CA94080 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned ( e.g. , puts, calls, warrants, options, convertible securities) 1. Title of Derivative Security (Instr. 3) 2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 4. Transaction Code (Instr. 8) 5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5) 6. Date Exercisable and Expiration Date (MM/DD/YY) 7. Title and Amount of Underlying Securities (Instr. 3 and 4) 8. Price of Derivative Security (Instr. 5) 9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4) 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4) 11. Nature of Indirect Beneficial Ownership (Instr. 4) Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares Stock Option (Right to Buy) $ 9.59 08/26/2025 A 91,076 ( 1 ) 08/25/2035 Common Stock 91,076 $ 0 91,076 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other MCCORMICK FRANK BRIDGEBIO ONCOLOGY THERAPEUTICS, INC. 256 EAST GRAND AVENUE, SUITE 104 SOUTH SAN FRANCISCO, CA94080 X Signatures /s/ Aaron Chan, Attorney-in-Fact 08/28/2025 Signature of Reporting Person Date

Explanation of Responses:

( 1 )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.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

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