As filed with the Securities and Exchange Commission on October 15, 2025. Registration No. 333-290426 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Amendment No. 2 to Form F-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Rubico Inc. (Exact name of Registrant as specified in its charter) Republic of the Marshall Islands (State or other jurisdiction of incorporation or organization) 4412 (Primary Standard Industrial Classification Code Number) N/A (I.R.S. Employer Identifi ...