Blue Water Acquisition Corp. III Sample Contracts

REGISTRATION RIGHTS AGREEMENT
Registration Rights Agreement • June 12th, 2025 • Blue Water Acquisition Corp. III • Blank checks • New York

THIS REGISTRATION RIGHTS AGREEMENT (this “Agreement”), dated as of June 9, 2025, is made and entered into by and among Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”), Blue Water Acquisition III LLC, a Delaware limited liability company (the “Sponsor”), BTIG, LLC (the “Representative”) (each party, together with the Sponsor, the Representative and any person or entity who hereafter becomes a party to this Agreement pursuant to Section 5.2 of this Agreement, a “Holder” and collectively, the “Holders”).

Blue Water Acquisition Corp. III Suite 363 Greenwich, CT 06830
Securities Subscription Agreement • March 31st, 2025 • Blue Water Acquisition Corp. III • Blank checks • New York

This agreement (the “Agreement”) is between Blue Water Acquisition III LLC, a Delaware limited liability company (the “Subscriber” or “you”), and Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company,” “we” or “us”). Pursuant to the terms hereof, the Company hereby accepts the offer the Subscriber has made to subscribe for and purchase 5,750,000 Class B Ordinary Shares, $0.0001 par value per share of the Company (the “Shares”), up to 750,000 of which are subject to surrender and cancellation by you if the underwriters of the initial public offering (“IPO”) of units (“Units”) of the Company, do not fully exercise their over-allotment option (the “Over-allotment Option”). The Company and the Subscriber’s agreements regarding such Shares are as follows:

INVESTMENT MANAGEMENT TRUST AGREEMENT
Investment Management Trust Agreement • June 12th, 2025 • Blue Water Acquisition Corp. III • Blank checks

This Investment Management Trust Agreement (this “Agreement”) is made effective as of June 9, 2025 by and between Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”), and Continental Stock Transfer & Trust Company, a New York corporation (the “Trustee”).

WARRANT AGREEMENT
Warrant Agreement • June 12th, 2025 • Blue Water Acquisition Corp. III • Blank checks • New York

THIS WARRANT AGREEMENT (this “Agreement”), dated as of June 9, 2025, is by and between Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”), and Continental Stock Transfer & Trust Company, a New York corporation, as warrant agent (in such capacity, the “Warrant Agent,” and also referred to herein as the “Transfer Agent”).

INDEMNITY AGREEMENT
Indemnification Agreement • June 12th, 2025 • Blue Water Acquisition Corp. III • Blank checks • New York

THIS INDEMNITY AGREEMENT (this “Agreement”) is made as of June 9, 2025, by and between Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”), and the undersigned (“Indemnitee”).

June 9, 2025 Blue Water Acquisition Corp. III Greenwich, CT 06830
Underwriting Agreement • June 12th, 2025 • Blue Water Acquisition Corp. III • Blank checks

This letter (this “Letter Agreement”) is being delivered to you in accordance with the Underwriting Agreement (the “Underwriting Agreement”) entered into by and among Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”) and BTIG, LLC as representative (the “Representative”) of the underwriters (the “Underwriters”), relating to an underwritten initial public offering (the “Public Offering”), of up to 25,300,000 of the Company’s units (including up to 3,300,000 units which may be purchased to cover over-allotments, if any) (the “Units”), each comprised of one Class A ordinary share, par value $0.0001 per share, of the Company (the “Class A Ordinary Shares”) and one-half of one redeemable warrant (each whole warrant, a “Warrant”). Each Warrant entitles the holder thereof to purchase one Class A Ordinary Share at a price of $11.50 per share, subject to adjustment. The Units shall be sold in the Public Offering pursuant to the registration statements on Form S

PRIVATE PLACEMENT UNITS PURCHASE AGREEMENT
Private Placement Units Purchase Agreement • June 12th, 2025 • Blue Water Acquisition Corp. III • Blank checks • New York

THIS PRIVATE PLACEMENT UNITS PURCHASE AGREEMENT, dated as of June 9, 2025 (as it may from time to time be amended, this “Agreement”), is entered into by and between Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”), and Blue Water Acquisition III LLC, a Delaware limited liability company (the “Purchaser”).

Underwriting Agreement between Blue Water Acquisition Corp. III and BTIG, LLC Dated June 9, 2025 (the “Agreement”)
Underwriting Agreement • June 12th, 2025 • Blue Water Acquisition Corp. III • Blank checks • New York

The undersigned, Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”), hereby confirms its agreement with BTIG, LLC (“BTIG” or the “Representative”) and with the other underwriters named on Schedule A hereto (if any), for which the Representative is acting as representative (the Representative and such other underwriters being collectively referred to herein as the “Underwriters” or, each underwriter individually, an “Underwriter,” provided that, if only BTIG is listed on such Schedule A, any references to the Underwriters shall refer exclusively to BTIG) as follows:

PRIVATE PLACEMENT UNITS PURCHASE AGREEMENT
Private Placement Units Purchase Agreement • June 12th, 2025 • Blue Water Acquisition Corp. III • Blank checks • New York

This PRIVATE PLACEMENT UNITS PURCHASE AGREEMENT (this “Agreement”) is made as of the 9th day of June, 2025, by and between Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”) and BTIG, LLC (“BTIG” or the “Subscriber”).

Blue Water Acquisition Corp. III
Administrative Services Agreement • June 12th, 2025 • Blue Water Acquisition Corp. III • Blank checks

This letter agreement by and between Blue Water Acquisition Corp. III (the “Company”) and Blue Water Acquisition III LLC, our sponsor, (the “Services Provider” or “Sponsor”), dated as of the date hereof, will confirm our agreement that, commencing on the date the securities of the Company are first listed on the Nasdaq Global Market (the “Listing Date”), pursuant to a Registration Statement on Form S-1 and prospectus filed with the U.S. Securities and Exchange Commission (the “Registration Statement”) and continuing until the earlier of the consummation by the Company of an initial business combination and the Company’s liquidation (in each case as described in the Registration Statement) (such earlier date hereinafter referred to as the “Termination Date”):

AMENDMENT NO. 1 TO UNDERWRITING AGREEMENT
Underwriting Agreement • April 14th, 2026 • Blue Water Acquisition Corp. III • Blank checks

THIS AMENDMENT NO. 1 TO THE UNDERWRITING AGREEMENT (this “Amendment”) is entered into as of November 25, 2025 and amends that certain Underwriting Agreement, dated as of June 9, 2025 (the “Underwriting Agreement”), by and between Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”), and BTIG, LLC (“BTIG”, and collectively with the Company, the “Parties”), in its capacity as representative of the underwriters. Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to them in the Underwriting Agreement.

CERTAIN IDENTIFIED INFORMATION HAS BEEN EXCLUDED FROM THE EXHIBIT BECAUSE IT IS BOTH (i) NOT MATERIAL AND (ii) THE TYPE THAT THE COMPANY TREATS AS PRIVATE OR CONFIDENTIAL. [***] indicates the redacted confidential portions of this exhibit. PURCHASE...
Purchase Agreement • November 28th, 2025 • Blue Water Acquisition Corp. III • Blank checks • New York

This PURCHASE AGREEMENT (this “Agreement”) is made effective and entered into as of November 25, 2025 (the “Effective Date”), by and among Yorkville BW Acquisition Sponsor, LLC, a Florida limited liability company (the “Purchaser”), Blue Water Acquisition Corp. III, a Cayman Islands exempted company, (the “SPAC”), and Blue Water Acquisition III LLC, a Delaware limited liability company (the “Sponsor”) (each a “Party” and, collectively, the “Parties”).

FORM OF INDEMNITY AGREEMENT
Indemnification Agreement • January 22nd, 2026 • Blue Water Acquisition Corp. III • Blank checks • Delaware

THIS INDEMNITY AGREEMENT (this “Agreement”) is made as of January [●], 2026, by and between Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”), and the undersigned (“Indemnitee”).

JOINDER TO AND AMENDMENT OF THE REGISTRATION RIGHTS AGREEMENT
Registration Rights Agreement • November 28th, 2025 • Blue Water Acquisition Corp. III • Blank checks

This JOINDER TO AND AMENDMENT OF THE REGISTRATION RIGHTS AGREEMENT, dated as of June 9, 2025, by and among Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”), Blue Water Acquisition III LLC, a Delaware limited liability company (the “Sponsor”) and certain other parties thereto (the “Agreement”) is delivered and entered into in accordance with Section 5.2 and Section 5.5 of the Agreement. Capitalized terms used and not defined herein have the meanings given to them in the Agreement.

Blue Water Acquisition Corp. III Greenwich, CT 06830
Sponsor and Insiders Obligations • November 28th, 2025 • Blue Water Acquisition Corp. III • Blank checks

This letter (this “Letter Agreement”) is being delivered to you in connection with the Purchase Agreement (the “Purchase Agreement”) entered into by and between Yorkville BW Acquisition Sponsor, LLC, a Florida limited liability company (the “Sponsor”), Blue Water Acquisition Corp. III, a Cayman Islands exempted company (the “Company”), and Blue Water Acquisition III, LLC (the “Prior Sponsor”). Certain capitalized terms used herein are defined in paragraph 8 hereof. Any capitalized terms that are used but not defined herein have the meanings ascribed to them in the Purchase Agreement. For good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, each of the Sponsor and the undersigned individuals, each of whom will be a member of the Company’s board of directors and/or management team upon the closing of the transactions provided for under the Purchase Agreement (each of the undersigned individuals, an “Insider” and collectively, the “Insiders”), her