ClearSign Technologies (CLIR) - 2022 Q4 - Annual Report

Table of Contents FORM 10-K SECURITIES AND EXCHANGE COMMISSION (Mark One) ☒ ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 For the fiscal year ended December 31, 2022 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) Washington (State or othe ...