Helix Sponsor Forfeits Shares; Cormorant Funds Buy into BBOT

Rhea-AI Filing Summary

Bihua Chen reported multiple ownership changes in BridgeBio Oncology Therapeutics, Inc. ("BBOT") tied to the closing of Helix Acquisition Corp. II's business combination and related subscription activity. On 08/11/2025, several Cormorant-managed funds purchased shares from the issuer: Fund III bought 760,496 shares, Fund V bought 639,110 shares, and Master Fund bought 5,598,425 shares, each at a purchase price of $10.7173 per share. These purchases were made under a subscription agreement with Helix.

Separately, the Sponsor forfeited shares for no consideration prior to closing: the forfeiture of 307,874 Class B ordinary shares and 152,940 shares of Common Stock is disclosed. The filing also explains that Helix's Class B shares converted into Class A shares and, following domestication, Class A shares converted one-for-one into the issuer's Common Stock. Ms. Chen is disclosed as manager with voting and investment discretion for the Sponsor and the Cormorant funds, while disclaiming beneficial ownership beyond any pecuniary interest.

Positive

• Cormorant-managed funds materially increased positions by purchasing 760,496, 639,110, and 5,598,425 shares at $10.7173 per share, demonstrating significant affiliated investment.
• Share class conversions and domestication were completed, converting Class B and Class A shares into the issuer's Common Stock on a one-for-one basis, simplifying capital structure.
• Clear disclosure of voting and investment discretion indicates Ms. Chen retains governance influence through her managerial roles over Sponsor and the Cormorant funds.

Negative

• Sponsor forfeited shares for no consideration (307,874 Class B shares and 152,940 Common Stock), which reduced certain Sponsor-held share counts.
• Related-party complexity and disclaimers: the filing disclaims beneficial ownership by each fund except to the extent of any pecuniary interest, which may complicate assessment of true economic ownership and control.

Insights

Financial Analyst

TL;DR: Large institutional purchases total ~7.0M shares at $10.7173 signal material backing from Cormorant funds.

The Form 4 shows sizable capital commitment from Cormorant-managed vehicles: a 5,598,425-share purchase by the Master Fund plus purchases by Fund III and Fund V at $10.7173 per share. These transactions occurred in connection with the business combination and a subscription agreement, increasing affiliated ownership positions in BBOT. The disclosure of Sponsor forfeitures for no consideration reduces certain Sponsor-held shares while conversion and domestication steps standardized share classes into common stock. For investors, the transactions reflect active affiliated participation in the post-combination capitalization.

Corporate Governance Expert

TL;DR: Disclosure clarifies control pathways but emphasizes disclaimers of beneficial ownership by related funds and manager.

The filing details the legal mechanics—Class B to Class A conversions, domestication, and one-for-one conversion into common stock—alongside Sponsor forfeitures and subscriptions by affiliated funds. It explicitly states Ms. Chen's managerial voting and investment discretion for the Sponsor and the Cormorant funds, while also including standard disclaimers that each fund disclaims beneficial ownership except to the extent of any pecuniary interest. This is a routine but important governance disclosure that clarifies where voting power and economic interests reside after the business combination.

SEC Form 4

FORM 4

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
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

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

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Chen Bihua

(Last) (First) (Middle)

C/O HELIX ACQUISITION CORP. II

200 CLARENDON STREET, 52ND FLOOR

(Street)

BOSTON MA 02116

(City) (State) (Zip)

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	X	10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
08/11/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	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
Common Stock	08/11/2025		M(3)		4,172,126	A	(3)	4,681,126	I	Via Helix Holdings II LLC(9)
Common Stock	08/11/2025		D(4)		152,940	D	$0	4,528,186	I	Via Helix Holdings II LLC(9)
Common Stock	08/11/2025		A(5)		760,496	A	$10.7173	2,187,536	I	Via Fund III(10)
Common Stock	08/11/2025		A(6)		639,110	A	$10.7173	1,542,710	I	Via Fund V(10)
Common Stock	08/11/2025		A(7)		5,598,425	A	$10.7173	5,667,785	I	Via Master Fund(10)
Common Stock	08/11/2025		A(8)		1,905,046	A	(8)	1,905,046	I	Via Fund IV(10)
Common Stock	08/11/2025		A(8)		1,762,760	A	(8)	3,305,470	I	Via Fund V(10)
Common Stock	08/11/2025		A(8)		284,571	A	(8)	5,952,356	I	Via Master Fund(10)

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 (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	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 (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (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: 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
Class B ordinary shares	(2)	08/11/2025		D(1)			307,874	(2)	(2)	Class A ordinary shares	307,874	$0	4,172,126	I	See footnote(9)
Class B ordinary shares	(2)	08/11/2025		M(3)			4,172,126	(2)	(2)	Class A ordinary shares	4,172,126	(3)	0	I	See footnote(9)

Explanation of Responses:

1. In connection with and prior to the closing of the business combination (the "Business Combination") between the Issuer (which was formerly known as Helix Acquisition Corp. II, "Helix") and TheRas, Inc. ("Legacy BBOT"), Helix Holdings II LLC (the "Sponsor") forfeited 307,874 Helix Class B ordinary shares for no consideration pursuant to the terms of the Sponsor Support Agreement dated February 28, 2025, between Sponsor, Helix, and Legacy BBOT (the "Sponsor Support Agreement").

2. The Helix Class B ordinary shares have no expiration date and automatically convert into Class A ordinary shares at the time of Helix's initial business combination as described under the heading "Description of Securities" in Helix's registration statement on Form S-1 (File No. 333-276591).

3. In connection with and prior to the closing of the Business Combination, 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, (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, par value $0.0001 per share ("Common Stock"), on a one-for-one basis.

4. In connection with and immediately prior to the closing of the Business Combination, the Sponsor forfeited 152,940 shares of Common Stock for no consideration, pursuant to the terms of the Sponsor Support Agreement.

5. In connection with and immediately prior to the closing of the Business Combination, pursuant to the terms of a subscription agreement dated February 28, 2025 between Helix and Cormorant Asset Management, LP (the "Subscription Agreement"), Cormorant Private Healthcare Fund III, LP ("Fund III"), which is an investment vehicle managed by Cormorant Asset Management, LP, purchased from the Issuer 760,496 shares of Common Stock at a purchase price of $10.7173 per share.

6. In connection with and immediately prior to the closing of the Business Combination, pursuant to the terms of the Subscription Agreement, Cormorant Private Healthcare Fund V, LP ("Fund V"), which is an investment vehicle managed by Cormorant Asset Management, LP, purchased from the Issuer 639,110 shares of Common Stock at a purchase price of $10.7173 per share.

7. In connection with and immediately prior to the closing of the Business Combination, pursuant to the terms of the Subscription Agreement, Cormorant Global Healthcare Master Fund, LP ("Master Fund"), which is an investment vehicle managed by Cormorant Asset Management, LP, purchased from the Issuer 5,598,425 shares of Common Stock at a purchase price of $10.7173 per share.

8. Upon the closing of the Business Combination, as contemplated by the terms of the Business Combination Agreement, dated as of February 28, 2025 (as amended, the "Business Combination Agreement"), by and among Helix, Legacy BBOT, and Helix Merger Sub, Inc., the owners of Legacy BBOT equity as of immediately prior to the closing, including Fund V, Master Fund, and Cormorant Private Healthcare Fund IV, LP ("Fund IV"), received as consideration therefor, shares of common stock of the Issuer.

9. Sponsor is the record holder of the securities reported herein. Fund III, Fund V, and Master Fund are the members of Sponsor. Bihua Chen is the manager of Sponsor and has voting and investment discretion with respect to the shares held of record by Sponsor. Each of Fund III, Fund V, Master Fund and Ms. Chen disclaims any beneficial ownership of the securities held by Sponsor other than to the extent of any pecuniary interest she or it may have therein, directly or indirectly.

10. Cormorant Asset Management, LP serves as the investment manager to Fund III, Fund IV, Fund V, and Master Fund (collectively, the "Cormorant Funds"). Cormorant Private Healthcare GP III, LLC ("GP III") is the general partner of Fund III; Cormorant Private Healthcare GP IV, LLC ("GP IV") is the general partner of Fund IV; Cormorant Private Healthcare GP V, LLC ("GP V") is the general partner of Fund V; and Cormorant Global Healthcare GP, LLC ("Global GP") is the general partner of the Master Fund. Bihua Chen serves as the managing member of GP III, GP IV, GP V, and Global GP, and as the general partner of Cormorant Asset Management, LP. Accordingly, Ms. Chen has voting and investment discretion with respect to the shares held by each of the Cormorant Funds and Cormorant Asset Management, LP. Ms. Chen disclaims any beneficial ownership of the securities held by each of the Cormorant Funds other than to the extent of any pecuniary interest she may have therein, directly or indirectly.

Remarks:

Ms. Chen serves on the Board of Directors of the Issuer. Sponsor and the Cormorant Funds may be deemed to be directors by deputization as a result of the service of Ms. Chen.

	/s/ Bihua Chen	08/13/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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FAQ

What transactions did Bihua Chen report on Form 4 for HLXB/BBOT?

The Form 4 reports transactions on 08/11/2025: Cormorant-managed funds purchased 760,496 (Fund III), 639,110 (Fund V), and 5,598,425 (Master Fund) shares at $10.7173 per share; the Sponsor forfeited 307,874 Class B shares and 152,940 Common Stock for no consideration.

How many shares did the Cormorant Master Fund buy and at what price?

The Cormorant Global Healthcare Master Fund, LP purchased 5,598,425 shares at a purchase price of $10.7173 per share.

What forfeitures did the Sponsor report in the filing?

The Sponsor forfeited 307,874 Helix Class B ordinary shares and 152,940 shares of Common Stock for no consideration pursuant to the Sponsor Support Agreement.

Does Bihua Chen have voting or investment control over the reported shares?

Yes. The filing states Ms. Chen is the manager of the Sponsor and the general/ managing member of entities controlling the Cormorant funds and therefore has voting and investment discretion over the shares held by those entities.

Did the filing explain conversion of different share classes?

Yes. The filing discloses that Helix Class B shares converted into Class A shares and, following domestication, Class A shares converted one-for-one into the issuer's Common Stock.