Form 8-K
8-K — ClearSign Technologies Corp
Accession: 0001104659-26-067517
Filed: 2026-05-28
Period: 2026-05-26
CIK: 0001434524
SIC: 3823 (INDUSTRIAL INSTRUMENTS FOR MEASUREMENT, DISPLAY, AND CONTROL)
Item: Other Events
Item: Financial Statements and Exhibits
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UNITED STATES
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 26, 2026
CLEARSIGN TECHNOLOGIES CORPORATION
(Exact name of registrant as specified in charter)
Delaware
001-35521
26-2056298
(State or other jurisdiction of
incorporation)
(Commission File Number)
(IRS Employer
Identification No.)
8023 E. 63rd Place, Suite 101
Tulsa,
Oklahoma 74133
(Address of principal executive offices
and zip code)
(918) 500-7312
(Registrant's telephone number, including area code)
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).
¨
Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)
¨
Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR240.14a-12)
¨
Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)).
¨
Pre-commencement communications pursuant to Rule 13e-4(c) under the
Exchange Act (17 CFR 240.13(e)-4(c))
Securities registered pursuant to Section 12(b) of the Act:
Title of each class
Trading Symbol(s)
Name
of each exchange on which
registered
Common Stock
CLIR
The Nasdaq Stock Market LLC
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).
Emerging growth
company ¨
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. ¨
Item 8.01 Other Events.
On
May 26, 2026, ClearSign Technologies Corporation (the “Company”) notified H.C. Wainwright & Co., LLC (“Wainwright”)
that it suspended the use of and terminated the prospectus supplement filed with the Securities and Exchange Commission (the “SEC”)
on July 17, 2025 (the “ATM Prospectus Supplement”), which forms a part of the Company’s “shelf” registration
statement on Form S-3 (File No. 333-288736) that became effective on July 28, 2025, relating to the At The Market Offering Agreement,
dated July 17, 2025, by and between the Company and Wainwright (the “ATM Agreement”), covering the sale of up to $10.39 million
in shares of its common stock (the “ATM Shares”). Prior to the suspension and termination of the ATM Prospectus Supplement,
no ATM Shares had been sold and all $10.39 million remained available for sale pursuant to the ATM Agreement and the ATM Prospectus Supplement.
The
Company will not make any sales of its shares of common stock pursuant to the ATM Agreement unless and until a new prospectus supplement
is filed. Other than the suspension of the sales of the Company’s shares of common stock pursuant to the ATM Agreement and the termination
of the related ATM Prospectus Supplement, the ATM Agreement remains in full force and effect.
A
copy of the ATM Agreement was filed as Exhibit 1.1 to the Company’s Current Report on Form 8-K filed with the SEC on July 18, 2025.
Item 9.01 Financial Statements and Exhibits.
(d) Exhibits.
Exhibit No.
Description
104
Cover Page Interactive Data File (embedded within the Inline XBRL document).
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: May 28, 2026
CLEARSIGN TECHNOLOGIES CORPORATION
By:
/s/ Colin James Deller
Name:
Colin James Deller
Title:
Chief Executive Officer
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Entity File Number
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Entity Registrant Name
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Entity Central Index Key
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Entity Tax Identification Number
26-2056298
Entity Incorporation, State or Country Code
DE
Entity Address, Address Line One
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