Clearsign Technologies Corporation

04/27/2026 | Press release | Distributed by Public on 04/27/2026 18:01

Amendment to Statement of Changes in Beneficial Ownership (Form 4/A)

FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
OMB APPROVAL
OMB Number: 3235-0287
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(Print or Type Responses)
1. Name and Address of Reporting Person *
Deller Colin James
2. Issuer Name and Ticker or Trading Symbol
ClearSign Technologies Corp [CLIR]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chief Executive Officer
(Last) (First) (Middle)
8023 E. 63RD PLACE, SUITE 101
3. Date of Earliest Transaction (Month/Day/Year)
02/26/2026
(Street)
TULSA, OK 74133
4. If Amendment, Date Original Filed (Month/Day/Year)
03/02/2026
6. Individual or Joint/Group Filing (Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City) (State) (Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 02/26/2026 A 7,001(1)(2) A $5.616(2) 34,967(1)(2) D
Common Stock 02/26/2026 F 3,501(1)(2) D $5.616(2) 31,466(1)(2) D
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 1474 (9-02)
Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
Deller Colin James
8023 E. 63RD PLACE, SUITE 101
TULSA, OK 74133
X Chief Executive Officer

Signatures

/s/ Colin J. Deller 04/27/2026
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) On March 2, 2026, the reporting person filed a Form 4 reporting the receipt of 210,043 shares of the Issuer's common stock, on a pre-reverse stock split basis, as a one-time bonus grant for services as an executive officer for the year ended December 31, 2025 (the "Original Form 4"). This amendment to the Original Form 4 is being filed to correct (i) the number of shares received in connection with the reporting person's one-time bonus grant, (ii) the number of shares withheld for tax purposes, and (iii) the number of securities beneficially owned following such transactions. The number of shares withheld is based on the closing price of the Issuer's common stock on February 26, 2026, of $5.616, as adjusted for the 1-for-10 reverse stock split effected by the Issuer on March 16, 2026.
(2) Amounts and price per share figures have been adjusted to reflect the 1-for-10 reverse stock split effected by the Issuer on March 16, 2026.
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure. Potential persons who are to respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB number.
Clearsign Technologies Corporation published this content on April 27, 2026, and is solely responsible for the information contained herein. Distributed via EDGAR on April 28, 2026 at 00:01 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]