Sec Form 4 Filing - Chen Bihua @ Helix Acquisition Corp. III - 2026-01-26

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 Chen Bihua 2. Issuer Name and Ticker or Trading Symbol Helix Acquisition Corp. III [ HLXC] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director X __ 10% Owner X __ Officer (give title below) _____ Other (specify below) Chairperson and CEO (Last) (First) (Middle) C/O CORMORANT ASSET MANAGEMENT, LP, 200 CLARENDON ST, 52ND FLOOR 3. Date of Earliest Transaction (MM/DD/YY) 01/26/2026 (Street) BOSTON, MA02116 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) _____ Form filed by One Reporting Person __ X __ 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 Class A Ordinary Shares 01/26/2026 A 497,500 A $ 10 497,500 I ( 1 ) See Footnote ( 1 )

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 Class B Ordinary Shares ( 2 ) ( 2 ) 01/22/2026 J( 3 ) 718,750 ( 2 ) ( 2 ) Class A Ordinary Shares 718,750 ( 2 ) ( 3 ) 4,252,500 I ( 1 ) See Footnote ( 1 )

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Chen Bihua C/O CORMORANT ASSET MANAGEMENT, LP 200 CLARENDON ST, 52ND FLOOR BOSTON, MA02116 X X Chairperson and CEO Helix Holdings III LLC C/O CORMORANT ASSET MANAGEMENT LP 200 CLARENDON STREET, 52ND FLOOR BOSTON, MA02116 X See Remarks Signatures /s/ Bihua Chen, Name: Bihua Chen 01/26/2026 Signature of Reporting Person Date /s/ Helix Holdings III LLC, by Bihua Chen, Managing Member 01/26/2026 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Helix Holdings III LLC is the record holder of the securities reported herein. Cormorant Private Healthcare Fund VI, LP ("Cormorant Fund VI") and Cormorant Global Healthcare Master Fund ("Cormorant Master Fund"), LP, together own 100% of the membership interests in Helix Holdings III LLC. Bihua Chen is the managing member of each of Cormorant Fund VI and Cormorant Master Fund and has voting and investment discretion with respect to the ordinary shares held of record by Helix Holdings III LLC. Bihua Chen disclaims any beneficial ownership of the securities held by Helix Holdings III LLC other than to the extent of any pecuniary interest she may have therein, directly or indirectly. ( 2 )As described in the Issuer's registration statement on Form S-1 (File No. 333-291933) ("Registration Statement"), under the heading "Description of Securities--Founder Shares and Private Placement Shares", the terms of the Class B ordinary shares, par value $0.0001 per share, provided at issuance that they would automatically convert into Class A ordinary shares, par value $0.0001 per share, concurrently with or immediately following the consummation of the Issuer's initial business combination or earlier at the option of the holder on a one-for-one basis, subject to adjustment for share sub-divisions, share capitalizations, reorganizations, recapitalizations and the like, and certain anti-dilution rights and have no expiration date. ( 3 )On January 22, 2026, the Issuer effected a share capitalization with respect to the Class B ordinary shares, resulting in the issue and allotment of 718,750 Class B ordinary shares to Helix Holdings III LLC.

Remarks: Helix Holdings III LLC may be deemed a director by deputization by virtue of its representation on the board of directors of the Issuer. See Exhibit 99.1 - Joint Filer Information, which is incorporated herein by reference and describes in further detail the relationships of the Reporting Persons to the Issuer.

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).

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