SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of the

Securities Exchange Act of 1934

Date of report (Date of earliest event reported): March 23, 2021

CLEARSIGN TECHNOLOGIES CORPORATION

(Exact name of registrant as specified in Charter)

12870 Interurban Avenue South

Seattle, Washington 98168

(Address of Principal Executive Offices)

206-673-4848

(Issuer Telephone number)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the Registrant under any of the following provisions (see General Instruction A.2 below).

Securities registered pursuant to Section 12(b) of the Act:

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

If 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.  ¨

On March 23, 2021, ClearSign Technologies Corporation (the “Company”) issued a press release announcing business updates and certain results of operations for the year ended December 31, 2020. The press release is included as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated by reference in its entirety into this Item 2.02.

Also on March 23, 2021, the Company held a conference call discussing certain results for the year ended December 31, 2020 and other business related information provided by the Company’s Chief Executive Officer. A transcript of this conference call is attached as Exhibit 99.2 to this Current Report on Form 8-K and is incorporated by reference in its entirety into this Item 2.02.

The information furnished with this Item 2.02, including Exhibits 99.1 and 99.2, shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference into any other filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in such a filing.

The statements in this Current Report on Form 8-K include forward-looking statements regarding the intent, belief or current expectations of the Company and members of its management team, as well as the assumptions on which such statements are based, and generally are identified by the use of words such as “may,” “will,” “seeks,” “strives,” “anticipates,” “believes,” “estimates,” “expects,” “plans,” “intends,” “should” or similar expressions. Actual results may differ materially from those contemplated by such forward-looking statements, including as a result of those factors set forth in the Risk Factors section of the Company’s most recent Annual Report on Form 10-K and all other filings with the Securities and Exchange Commission after that date. Forward-looking statements speak only as of the date they are made, and the Company undertakes no obligation to update or revise forward-looking statements to reflect changed assumptions, the occurrence of unanticipated events or changes to future operating results over time, or revise forward-looking unless required by law.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

Dated: March 25, 2021