Clearthink 1 Acquisition(CTAAU) - Prospectus(update)

Washington, D.C. 20549 Amendment No. 1 As filed with the U.S. Securities and Exchange Commission on February 11, 2026 Registration No. 333-292967 UNITED STATES SECURITIES AND EXCHANGE COMMISSION to FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 ClearThink 1 Acquisition Corp. (Exact name of registrant as specified in its charter) Cayman Islands 6770 N/A (State or other jurisdiction of incorporation or organization) (Primary Standard Industrial Classification Code Number) (I.R.S. Employer Id ...