0001493152-26-008334 Sample Contracts

Contract
Registration Rights Agreement • February 27th, 2026 • Clearthink 1 Acquisition Corp. • Blank checks • New York

THIS REGISTRATION RIGHTS AGREEMENT (this “Agreement”), dated February 25, 2026, entered into by and among ClearThink 1 Acquisition Corp., a Cayman Islands exempted company limited by shares, with principal offices at c/o Ogier Global (Cayman) Limited, 89 Nexus Way, Camana Bay, Grand Cayman, KY1-9009, Cayman Islands (the “Company”), ClearThink 1 Sponsor LLC, a Florida limited liability company (the “Sponsor”), and the other parties listed on the signature pages hereto (each such party, together with the Sponsor 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”).

Contract
Indemnity Agreement • February 27th, 2026 • Clearthink 1 Acquisition Corp. • Blank checks • Delaware

THIS INDEMNITY AGREEMENT (this “Agreement”), dated February 25, 2026, by and between ClearThink 1 Acquisition Corp., a Cayman Islands exempted company (the “Company”), and the undersigned (“Indemnitee”).

12,500,000 Units CLEARTHINK 1 Acquisition Corp UNDERWRITING AGREEMENT
Underwriting Agreement • February 27th, 2026 • Clearthink 1 Acquisition Corp. • Blank checks • New York

ClearThink 1 Acquisition Corp, a Cayman Islands exempted company with limited liability (the “Company”), hereby confirms its agreement with D. Boral Capital LLC (the “Representative”) and with the other underwriters named on Schedule A hereto (if any), for which the Representative is acting as the representative (the “Representative” and such other underwriters being collectively referred to herein as the “Underwriters” or, each underwriter individually, an “Underwriter”) as follows:

Contract
Indemnification Agreement • February 27th, 2026 • Clearthink 1 Acquisition Corp. • Blank checks • Delaware

THIS INDEMNITY AGREEMENT (this “Agreement”), dated February 25, 2026, by and between ClearThink 1 Acquisition Corp., a Cayman Islands exempted company (the “Company”), and the undersigned (“Indemnitee”).

February 25, 2026 ClearThink 1 Acquisition Corp. Suite 202 Boca Raton, Florida 33432 Re: Initial Public Offering Ladies and Gentlemen:
Underwriting Agreement • February 27th, 2026 • Clearthink 1 Acquisition Corp. • 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 ClearThink 1 Acquisition Corp., a Cayman Islands exempted company (the “Company”), and D. Boral Capital LLC, the underwriter (the “Underwriter”), relating to an underwritten initial public offering (the “Public Offering”), of up to 12,500,000 of the Company’s units (including up to 1,875,000 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 right (“Right”) to receive one-fifth (1/5) of one Class A Ordinary Share upon the consummation of an initial business combination. The Units shall be sold in the Public Offering pursuant to the registration statement on Form S-1 (File No. 333-292967), the registration statement on Form S-1MEF (File No. 333-293666) and prospectus

RIGHTS AGREEMENT
Rights Agreement • February 27th, 2026 • Clearthink 1 Acquisition Corp. • Blank checks • New York

This Rights Agreement (this “Agreement”) is dated February 25, 2026, between ClearThink 1 Acquisition Corp., a Cayman Islands exempted company limited by shares, with principal offices c/o Ogier Global (Cayman) Limited, 89 Nexus Way, Camana Bay, Grand Cayman, KY1-9009, the Cayman Islands (the “Company”) and VStock Transfer LLC, a California limited liability company, with offices at 18 Lafayette Place, Woodmere, NY 11598 (the “Rights Agent”).

Administrative Services Agreement February 25, 2026
Administrative Services Agreement • February 27th, 2026 • Clearthink 1 Acquisition Corp. • Blank checks
INVESTMENT MANAGEMENT TRUST AGREEMENT
Investment Management Trust Agreement • February 27th, 2026 • Clearthink 1 Acquisition Corp. • Blank checks

Pursuant to Section 1(k) of the Investment Management Trust Agreement between ClearThink 1 Acquisition Corp. (the “Company”) and Equiniti Trust Company, LLC (the “Trustee”), dated as of February 25, 2026 (the “Trust Agreement”), the Company hereby requests that you deliver to the redeeming Public Shareholders of the Company $[●] of the principal and interest income earned on the Property as of the date hereof. Capitalized terms used but not defined herein shall have the meanings set forth in the Trust Agreement.