ClearSign Technologies (CLIR) - 2023 Q3 - Quarterly Report

UNITED STATES Washington, D.C. 20549 (Mark One) ☒ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended September 30, 2023 OR ☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the transition period from ______________ to _______________ Commission File Number 001-35521 CLEARSIGN TECHNOLOGIES CORPORATION (Exact name of registrant as specified in its charter) Delaware (State or other jurisdiction of i ...