Table of Contents As filed with the Securities and Exchange Commission on February 12, 2026 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Amendment No. 5 to FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 Clear Street Group Inc. (Exact Name of Registrant as Specified in Its Charter) (State or Other Jurisdiction of Incorporation or Organization) Delaware 6211 86-2376416 (Primary Standard Industrial Classification Code Number) (I.R.S. Employer Identification Number) ...

UNDER THE SECURITIES ACT OF 1933 Clear Street Group Inc. (Exact Name of Registrant as Specified in Its Charter) Table of Contents As filed with the Securities and Exchange Commission on January 20, 2026 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-1 REGISTRATION STATEMENT (State or Other Jurisdiction of Incorporation or Organization) (Primary Standard Industrial Classification Code Number) Delaware 6211 86-2376416 (I.R.S. Employer Identification Number) 150 Greenwich Street ...