Mark C. McKenna - 11 Aug 2025 Form 4 Insider Report for BridgeBio Oncology Therapeutics, Inc. (HLXB)

Role: Former Director
Signature: /s/ Mark C. McKenna
Issuer symbol: HLXB
Transactions as of: 11 Aug 2025
Net transactions value: $0
Form type: 4
Filing time: 11 Aug 2025, 17:01:51 UTC
Previous filing: 20 Jun 2025
Next filing: 09 Jan 2026
SEC: View on sec.gov

Reporting Owners (1)

Name	Relationship	Address	Signature	Signature date	CIK
McKenna Mark C.	Former Director	C/O HELIX ACQUISITION CORP. II, 200 CLARENDON STREET, 52ND FLOOR, BOSTON	/s/ Mark C. McKenna	11 Aug 2025	0001749623

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	BBOT	Common Stock	Options Exercise		+30,000			30,000	11 Aug 2025	Direct	F1

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	Class B ordinary shares	Options Exercise	$0	-30,000	-100%	$0.000000	0	11 Aug 2025	Class A ordinary shares	30,000		Direct	F1

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

Mark C. McKenna is no longer subject to Section 16 filing requirements. Form 4 or Form 5 obligations may continue.

Explanation of Responses:

Id	Content
F1	In connection with and prior to the closing of the business combination between the Issuer (which was formerly known as Helix Acquisition Corp. II, "Helix") and TheRas, Inc., among other things, (i) each of Helix's Class B ordinary shares converted into one Helix Class A ordinary share, on a one-for-one basis, as described under the heading "Description of Securities" in Helix's Registration Statement on Form S-1 (File No. 333-276591), (ii) Helix migrated to and domesticated as a Delaware corporation in accordance with Section 388 of the Delaware General Corporation Law, as amended, and the Cayman Islands Companies Act (As Revised) (the "Domestication"), and (iii) as a result of the Domestication, each Class A ordinary share of Helix converted into one share of the Issuer's common stock, on a one-for-one basis. Prior to such conversion, the Helix Class B ordinary shares had no expiration date.

Content

In connection with and prior to the closing of the business combination between the Issuer (which was formerly known as Helix Acquisition Corp. II, "Helix") and TheRas, Inc., among other things, (i) each of Helix's Class B ordinary shares converted into one Helix Class A ordinary share, on a one-for-one basis, as described under the heading "Description of Securities" in Helix's Registration Statement on Form S-1 (File No. 333-276591), (ii) Helix migrated to and domesticated as a Delaware corporation in accordance with Section 388 of the Delaware General Corporation Law, as amended, and the Cayman Islands Companies Act (As Revised) (the "Domestication"), and (iii) as a result of the Domestication, each Class A ordinary share of Helix converted into one share of the Issuer's common stock, on a one-for-one basis. Prior to such conversion, the Helix Class B ordinary shares had no expiration date.

Remarks:

The Reporting person was a director of Helix prior to the Domestication and resigned from such role effective as of August 11, 2025, immediately prior to the Domestication.