8-K

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):May 2, 2023

CLEARSIGN TECHNOLOGIES CORPORATION

(Exact name of registrant as specified in Charter)

8023 E. 63rd Place, Suite 101

Tulsa**,Oklahoma 74133**

(Address of Principal Executive Offices)

(918) 236-6461

(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. ¨

As previously disclosed by ClearSign Technologies Corporation (the “Company”) in its Current Report on Form 8-K filed on November 4, 2022, the Company received a letter (the “Initial Notice”) from the Listing Qualifications department of The Nasdaq Stock Market (“Nasdaq”) on November 1, 2022, indicating that the Company was not in compliance with the required minimum bid price of $1 per share (the “Minimum Bid Price Requirement”) as required under Nasdaq Listing Rule 5550(a)(2). The Initial Notice provided the Company with 180 calendar days, or until May 1, 2023, to regain compliance with Nasdaq Listing Rule 5550(a)(2).

On May 2, 2023, the Company received a second letter from Nasdaq granting the Company an additional 180 calendar days, or until October 30, 2023, to regain compliance with the Minimum Bid Price Requirement for continued listing on The Nasdaq Capital Market pursuant to Nasdaq Listing Rule 5550(a)(2) (the “Notice”).

Nasdaq further stated in the Notice that its determination to grant an extension was based on the Company meeting the continued listing requirement for market value of publicly held shares and all other applicable requirements for initial listing on The Nasdaq Capital Market, with the exception of the Minimum Bid Price Requirement, and the Company’s written notice of its intention to cure the deficiency during the second compliance period by effecting a reverse stock split, if necessary.

The Notice has no immediate effect on the listing or trading of the Company’s common stock and the common stock will continue to trade on The Nasdaq Capital Market under the symbol “CLIR.”

d)  Exhibits.

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SIGNATURE

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

Dated: May 2, 2023

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