Table of Contents As filed with the U.S. Securities and Exchange Commission on December 17, 2025 Registration No. 333-290602 UNITED STATES SECURITIES AND EXCHANGE COMMISSION TO FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Black Spade Acquisition III Co (Exact Name of Registrant as Specified in Its Charter) Washington, D.C. 20549 AMENDMENT NO. 3 (Address, including zip code, and telephone number, including area code, of registrant's principal executive offices) Cogency Global Inc. 122 Eas ...