{"url_path":"/sec/clir/10-q/2026/cover-page","section_key":"cover-page","section_title":"Cover Page","topic":"sec","document":{"doc_type":"10-Q","doc_date":"2026-05-15","source_url":"https://www.sec.gov/Archives/edgar/data/1434524/0001104659-26-061940-index.html","accession_number":"0001104659-26-061940","cik":"0001434524","ticker":"CLIR","issuer_name":"ClearSign Technologies Corp","edgar_url":"https://www.sec.gov/Archives/edgar/data/1434524/0001104659-26-061940-index.html","primary_entity_key":"0001434524","primary_entity_name":"ClearSign Technologies Corp"},"word_count":705,"has_tables":true,"body_markdown":"CLEARSIGN TECHNOLOGIES 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of Contents](#TOC)\n\n​\n\n​\n\n**UNITED STATES**\n\n**SECURITIES AND EXCHANGE COMMISSION**\n\n**Washington, D.C. 20549**\n\n**FORM ****10-Q**\n\n**(Mark One)**\n\n******☒**\n\n**QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934**\n\n​\n\n**For the quarterly period ended****March 31, 2026**\n\n**OR**\n\n​\n\n******☐**\n\n**TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934**\n\n​\n\n**For the transition period from ______________ to _______________**\n\n**Commission File Number:****001-35521**\n\n**CLEARSIGN TECHNOLOGIES CORPORATION**\n\n(Exact name of registrant as specified in its charter)\n\n​\n\n**Delaware**\n(State or other jurisdiction of\nincorporation or organization)\n\n  ​ ​ ​\n\n**26-2056298**\n(I.R.S. Employer\nIdentification No.)\n\n​\n\n**8023 E. 63rd Place, Suite 101**\n\n**Tulsa****,****Oklahoma********74133**\n\n(Address of principal executive offices)\n\n(Zip Code)\n\n​\n\n**(****918****)****500-7312**\n\n(Registrant’s telephone number, including area code)\n\n​\n\nSecurities registered pursuant to Section 12(b) of the Act:\n\n​\n\n**Title of each class**\n\n**  ​ ​ ​**\n\n**Trading Symbol(s)**\n\n**  ​ ​ ​**\n\n**Name of each exchange on which registered**\n\n**Common Stock**\n\n​\n\n**CLIR**\n\n​\n\n**The****Nasdaq****Stock Market LLC**\n\n​\n\nIndicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days. Yes ⌧ No ☐\n\nIndicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files). Yes ⌧ No ☐\n\nIndicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company” and “emerging growth company” in Rule 12b-2 of the Exchange Act.\n\n​\n\nLarge accelerated filer ☐\n\n  ​ ​ ​\n\nAccelerated filer ☐\n\n \n\n \n\n \n\nNon-accelerated filer ⌧\n\n \n\nSmaller reporting company ☒\n\n​\n\n​\n\n​\n\n \n\n \n\nEmerging growth company ☐\n\n​\n\nIf an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐\n\nIndicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes ☐  No ⌧\n\n​\n\nAs of May 11, 2026, the issuer has 5,412,633 shares of common stock, par value $0.0001, issued and outstanding.\n\n​\n\n​\n\n​\n\n[Table of Contents](#TOC)\n\n​\n\n**TABLE OF CONTENTS**\n\n​\n\n​\n\n​\n\n​\n\n[PART I](#PARTIFINANCIALINFORMATION_758876)\n\n[FINANCIAL INFORMATION](#PARTIFINANCIALINFORMATION_758876)\n\n​\n\n​\n\n​\n\n​\n\n[Item 1.](#ITEM1CONDENSEDCONSOLIDATEDFINANCIALSTATE)\n\n[Financial Statements (unaudited)](#PARTIFINANCIALINFORMATION_758876)\n\n​\n\n​\n\n​\n\n​\n\n​\n\n[Condensed Consolidated Balance Sheets as of March 31, 2026 and December 31, 2025](#ConsolidatedBalanceSheets_370122)\n\n1\n\n​\n\n​\n\n​\n\n​\n\n[Condensed Consolidated Statements of Operations and Comprehensive Loss for the three months ended March 31, 2026 and 2025](#ConsolidatedStatementsofOperations_52792)\n\n2\n\n​\n\n​\n\n​\n\n​\n\n[Condensed Consolidated Statements of Stockholders’ Equity for the three months ended March 31, 2026 and 2025](#CondensedConsolidatedStatementsofEquity_)\n\n3\n\n​\n\n​\n\n​\n\n​\n\n[Condensed Consolidated Statements of Cash Flows for the three months ended March 31, 2026 and 2025](#ConsolidatedStatementsofCashFlows_17141)\n\n4\n\n​\n\n​\n\n​\n\n​\n\n[Notes to Condensed Consolidated Financial Statements](#NotestoUnauditedCondensedConsolidatedFin)\n\n5\n\n​\n\n​\n\n​\n\n[Item 2.](#ITEM2MANAGEMENTSDISCUSSIONANDANALYSISOFF)\n\n[Management’s Discussion and Analysis of Financial Condition and Results of Operations](#ITEM2MANAGEMENTSDISCUSSIONANDANALYSISOFF)\n\n19\n\n​\n\n​\n\n​\n\n[Item 3.](#ITEM3QUANTITATIVEANDQUALITATIVEDISCLOSUR)\n\n[Quantitative and Qualitative Disclosures About Market Risk](#ITEM3QUANTITATIVEANDQUALITATIVEDISCLOSUR)\n\n23\n\n​\n\n​\n\n​\n\n[Item 4.](#ITEM4CONTROLSANDPROCEDURES_588585)\n\n[Controls and Procedures](#ITEM4CONTROLSANDPROCEDURES_588585)\n\n23\n\n​\n\n​\n\n​\n\n[PART II](#PARTIIOTHERINFORMATION_352863)\n\n[OTHER INFORMATION](#PARTIIOTHERINFORMATION_352863)\n\n24\n\n​\n\n​\n\n​\n\n[Item 1.](#ITEM1LEGALPROCEEDINGS_598160)\n\n[Legal Proceedings](#ITEM1LEGALPROCEEDINGS_598160)\n\n24\n\n​\n\n​\n\n​\n\n[Item 1A.](#ITEM1ARISKFACTORS_413736)\n\n[Risk Factors](#ITEM1ARISKFACTORS_413736)\n\n24\n\n​\n\n​\n\n​\n\n[Item 2.](#ITEM2UNREGISTEREDSALESOFEQUITYSECURITIES)\n\n[Unregistered Sales of Equity Securities and Use of Proceeds](#ITEM2UNREGISTEREDSALESOFEQUITYSECURITIES)\n\n24\n\n​\n\n​\n\n​\n\n[Item 3.](#ITEM3DEFAULTSUPONSENIORSECURITIES_571412)\n\n[Defaults Upon Senior Securities](#ITEM3DEFAULTSUPONSENIORSECURITIES_571412)\n\n24\n\n​\n\n​\n\n​\n\n[Item 4.](#ITEM4MINESAFETYDISCLOSURES_729119)\n\n[Mine Safety Disclosures](#ITEM4MINESAFETYDISCLOSURES_729119)\n\n24\n\n​\n\n​\n\n​\n\n[Item 5.](#ITEM5OTHERINFORMATION_785228)\n\n[Other Information](#ITEM5OTHERINFORMATION_785228)\n\n24\n\n​\n\n​\n\n​\n\n[Item 6.](#ITEM6EXHIBITS_368004)\n\n[Exhibits](#ITEM6EXHIBITS_368004)\n\n25\n\n​\n\n​\n\n​\n\n​\n\n[SIGNATURES](#SIGNATURES_969179)\n\n27\n\n​\n\n​\n\n​\n\n​\n\n​\n\n​\n\n​\n\n​\n\n[Table of Contents](#TOC)\n\n​\n\nPART I - FINANCIAL INFORMATION"}