Sec Form 4 Filing - Seth Ketan @ Blue Acquisition Corp/Cayman - 2026-06-16

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 Seth Ketan 2. Issuer Name and Ticker or Trading Symbol Blue Acquisition Corp/Cayman [ BACC] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director X __ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) C/O BLUE ACQUISITION CORP., 1601 ANITA LANE 3. Date of Earliest Transaction (MM/DD/YY) 06/16/2026 (Street) NEWPORT BEACH, CA92660 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 Class A ordinary shares 06/16/2026 J( 1 ) 391,000 ( 1 ) ( 2 ) D 0 I See footnotes ( 1 ) ( 2 )

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 Rights to receive Class A ordinary shares ( 3 ) 06/16/2026 J( 1 ) 391,000 ( 3 ) ( 3 ) ( 3 ) Class A Ordinary Shares 39,100 ( 3 ) ( 1 ) 0 ( 3 ) I See footnote ( 3 ) Class B ordinary shares ( 4 ) 06/16/2026 J( 1 ) 6,769,913 ( 4 ) ( 4 ) ( 4 ) Class A Ordinary Shares 6,769,913 ( 4 ) ( 1 ) 0 ( 4 ) I See footnote ( 4 )

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Seth Ketan C/O BLUE ACQUISITION CORP. 1601 ANITA LANE NEWPORT BEACH, CA92660 X Signatures /s/ Ketan Seth 06/18/2026 Signature of Reporting Person Date

Explanation of Responses:

( 1 )On June 16, 2026, Ketan Seth, the former Chief Executive Officer of Blue Acquisition Corp. (the "Issuer") (a position from which Mr. Seth resigned as of June 9, 2026), resigned from his position as the managing member of Blue Holdings Management LLC ("BHM"), the managing member of Blue Holdings Sponsor LLC ("Sponsor"), and forfeited and surrendered to BHM any and all rights, tile or interest in and to any membership units of BHM and any securities of the Issuer, including, without limitation, any right, title or interest to or in any securities of the surviving public company upon and after the consummation (the "Closing"), if any, of the proposed business combination transaction between the Issuer and Blockfusion USA, Inc. Upon the resignation and forfeiture by Ketan Seth, he owns no Class A ordinary shares, Class B ordinary shares or any other securities convertible into Class A or Class B ordinary shares of the Issuer. ( 2 )Reflects the 391,000 Class A ordinary shares of the Issuer that are included in the 391,000 private placement units of the Issuer purchased by Sponsor. Each private placement unit was purchased for $10 per unit and consists of one Class A ordinary share and one right to receive one-tenth (1/10) of one Class A ordinary share upon consummation of the Issuer's initial business combination. ( 3 )Represents the 39,100 Class A ordinary shares, which may be acquired by Sponsor upon the conversion of 391,000 rights (included in the Sponsor's private placement units) upon consummation of the Issuer's initial business combination. As described in the Registration Statement on Form S-1 for the initial public offering of the securities of the Issuer (File No. 333-287281) (the "Registration Statement") under the heading "Description of Securities-Share Rights," each right will automatically convert into one-tenth (1/10) of one Class A ordinary share upon consummation of the Issuer's initial business combination, subject to certain adjustments described therein. No fractional Class A ordinary shares will be issued upon conversion of such rights. ( 4 )Represents 6,769,913 Class B ordinary shares held by the Sponsor acquired pursuant to a subscription agreement by and between the Issuer and the Sponsor. As described in the Registration Statement under the heading "Description of Securities--Founder Shares," the Class B ordinary shares will automatically convert into shares of Class A ordinary shares at the time of the Issuer's initial business combination, or at any time prior to the Issuer's initial business combination, at the option of the holder, on a one-for-one basis, subject to certain adjustments.

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