As filed with the Securities and Exchange Commission on July 3, 2024 Registration No. 333-279550 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 CLEARSIGN TECHNOLOGIES CORPORATION Copies to: Blake Baron, Esq. Nimish Patel, Esq. Mitchell Silberberg & Knupp LLP 437 Madison Avenue New York, New York 10022 Phone: (212) 509-3900 (Exact name of registrant as specified in its charter) | Delaware | | --- | | ...