Table of Contents As filed with the Securities and Exchange Commission on November 19, 2025. Registration Statement No. 333-290415 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 AMENDMENT NO. 1 TO FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Andersen Group Inc. Mark L. Vorsatz Chairman and Chief Executive Officer Andersen Group Inc. 333 Bush Street Suite 1700 San Francisco, California 94104 (415) 764-2700 (Name, address, including zip code, and telephone number, ...