Statement of Changes in Beneficial Ownership (Form 4)

FORM 4 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 that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

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

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(Print or Type Responses)

1. Name and Address of Reporting Person * You Harry L. 2. Issuer Name and Ticker or Trading Symbol Horizon Quantum Holdings Ltd. [HQ] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director __X__ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) 1180 NORTH TOWN CENTER DR, SUITE 100 3. Date of Earliest Transaction (Month/Day/Year) 11/03/2026 (Street) LAS VEGAS, NV 89144 4. If Amendment, Date 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 (City) (State) (Zip) 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 Class A Ordinary Shares 11/03/2026 J(1) 1,163,484 D $ 0 0 I See footnote(3) Class A Ordinary Shares 11/03/2026 J(1) 1,163,484 A $ 0 1,212,698 D

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

Warrants

$11.5

11/03/2026

J(2)

1,442,330

04/18/2026

03/19/2031

Class A Ordinary Shares

1,442,330

$ 0

0

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
You Harry L. 1180 NORTH TOWN CENTER DR SUITE 100 LAS VEGAS, NV 89144	X	X

Signatures

/s/ Harry L. You		11/05/2026
**Signature of Reporting Person		Date

Explanation of Responses:

*	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).
(1)	dMY Squared Sponsor, LLC (the "Sponsor") distributed an aggregate of 1,163,484 Class A Ordinary Shares to its members, pro rata, for no consideration. Harry You, the managing member of the Sponsor, received 1,163,484 of the Class A Ordinary Shares distributed by the Sponsor in respect of his membership interest and now owns such shares directly. The distribution effected only a change in the form of Mr. You's beneficial ownership and is exempt from Section 16(b) pursuant to Rule 16a-13.
(2)	The Sponsor distributed an aggregate of 2,884,660 warrants to its members, pro rata, for no consideration. Harry You, the managing member of the Sponsor, received 1,442,330 of the warrants distributed by the Sponsor in respect of his membership interest and now owns the warrants directly. The distribution effected only a change in the form of Mr. You's beneficial ownership and is exempt from Section 16(b) pursuant to Rule 16a-13.
(3)	Prior to the distribution reported herein, Sponsor was the record holder of such securities. Harry L. You is the managing member of the Sponsor and has voting and investment discretion with respect to the securities held of record by the Sponsor.

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