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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1. Name and Address of Reporting Person * ANGELO MARK 2. Issuer Name and Ticker or Trading Symbol Blue Water Acquisition Corp. III [BLUW] 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) C/O YORKVILLE ACQUISITION CORP, 1012 SPRINGFIELD AVENUE 3. Date of Earliest Transaction (Month/Day/Year) 08/11/2026 (Street) MOUNTAINSIDE, NJ 07092 4. If Amendment, Date Original Filed (Month/Day/Year) 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 (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

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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

Convertible Working Capital Note(1)

(1)

08/11/2026

A

75,000

(1)

(2)

Class A ordinary shares

75,000

(3)

75,000

I

By Yorkville BW Acquisition Sponsor, LLC(4)

Convertible Working Capital Note(1)

(1)

08/11/2026

A

37,500

(1)

(2)

Warrants

37,500

(3)

37,500

I

By Yorkville BW Acquisition Sponsor, LLC(4)

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
ANGELO MARK C/O YORKVILLE ACQUISITION CORP 1012 SPRINGFIELD AVENUE MOUNTAINSIDE, NJ 07092	X	X
Yorkville BW Acquisition Sponsor, LLC C/O YORKVILLE ACQUISITION CORP 1012 SPRINGFIELD AVENUE MOUNTAINSIDE, NJ 07092		X

Signatures

/s/ Mark Angelo		08/13/2026
**Signature of Reporting Person		Date
/s/ Mark Angelo, Yorkville BW Acquisition Sponsor, LLC		08/13/2026
**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)	On August 11, 2026, the Issuer entered into an Amended and Restated Working Capital Note ("Note") promising to pay Yorkville BW Acquisition Sponsor, LLC ( "Sponsor") $750,000. All amounts due under the Note may be converted into 75,000 units. Each unit consists of one Class A ordinary share ("Ordinary Shares") and one-half of one warrant to purchase one Ordinary Share, resulting in 75,000 Ordinary Shares and warrants to purchase 37,500 Ordinary shares of the Issuer at the discretion of the Sponsor upon the consummation of the business combinations. The warrants shall have the same terms and conditions as the warrants issued in the initial public offering. The acquisition of the Note by the Sponsor, and the beneficial acquisition of the Note by the Sponsor's members, is an exempt transaction under Rule 16b-3, promulgated by the U.S. Securities and Exchange Commission pursuant to the Securities Act of 1934, as amended.
(2)	The principal balance of the Note shall be payable by the Issuer on the earlier of the date on which the Issuer consummates its initial business combination or the date that the winding up of the Issuer is effective, and is convertible at the Sponsor's election upon the consummation of the initial business combination.
(3)	The Issuer's Ordinary Shares and warrants are described under the heading "Description of Securities" in the Issuer's Registration Statement on Form S-1 (File No. 333-285075).
(4)	Yorkville Advisors Global, LP ("Yorkville LP") is the manager of the Sponsor and holds voting and investment discretion over the securities held by the Sponsor. YA II PN, Ltd. ("YA II PN") is a member of the Sponsor. Yorkville LP is the investment manager of YA II PN, and Yorkville Advisors Global II, LLC ("Yorkville LLC") is the General Partner of Yorkville LP. Mr. Angelo serves as President of Yorkville LLC and makes all investment decisions for YA II PN. As such, Mr. Angelo may be deemed to have beneficial ownership of the securities held by the Sponsor. Mr. Angelo disclaims any beneficial ownership of the reported securities, except to the extent of his pecuniary interest therein.

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