# EDGAR Filing Document

**Accession Number:** 0001434524
**File Stem:** 0001104659-26-025867
**Filing Date:** 2026-3
**Character Count:** 18578
**Document Hash:** be75cf39e86aec47dd5b7a18cc5a8066
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-26-025867.hdr.sgml**: 20260310

**ACCESSION NUMBER**: 0001104659-26-025867

**CONFORMED SUBMISSION TYPE**: 8-K

**PUBLIC DOCUMENT COUNT**: 15

**CONFORMED PERIOD OF REPORT**: 20260306

**ITEM INFORMATION**: Material Modifications to Rights of Security Holders

**ITEM INFORMATION**: Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year

**ITEM INFORMATION**: Regulation FD Disclosure

**ITEM INFORMATION**: Financial Statements and Exhibits

**FILED AS OF DATE**: 20260310

**DATE AS OF CHANGE**: 20260310

**FILER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** ClearSign Technologies Corp
- **CENTRAL INDEX KEY:** 0001434524
- **STANDARD INDUSTRIAL CLASSIFICATION:** INDUSTRIAL INSTRUMENTS FOR MEASUREMENT, DISPLAY, AND CONTROL [3823]
- **ORGANIZATION NAME:** 08 Industrial Applications and Services
- **EIN:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 8-K
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-35521
- **FILM NUMBER:** 26739595

**BUSINESS ADDRESS:**
- **STREET 1:** 8023 E. 63RD PLACE, SUITE 101
- **CITY:** TULSA
- **STATE:** OK
- **ZIP:** 74133
- **BUSINESS PHONE:** (918) 500-7312

**MAIL ADDRESS:**
- **STREET 1:** 8023 E. 63RD PLACE, SUITE 101
- **CITY:** TULSA
- **STATE:** OK
- **ZIP:** 74133

**FORMER COMPANY:**
- **FORMER CONFORMED NAME:** CLEARSIGN COMBUSTION CORP
- **DATE OF NAME CHANGE:** 20080507

?xml version='1.0' encoding='ASCII'?

**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): March 6, 2026**

**CLEARSIGN TECHNOLOGIES CORPORATION**

**(Exact name of registrant as specified in charter)**

---

| | | |
|:---|:---|:---|
| **Delaware** | **001-35521** | **26-2056298** |
| **(State or other jurisdiction of <br> incorporation)** | **(Commission File Number)** | **(IRS Employer <br> Identification No.)** |

---

**8023 E. 63rd Place, Suite 101**

**Tulsa** **, Oklahoma 74133**

**(Address of Principal Executive Offices and Zip Code)**

**(918) 236-6461**

**(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 <br> 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 3.03** | **Material Modification to Rights of Security Holders.** |

---

To the extent required by Item 3.03 of Form 8-K, the information regarding the Reverse Stock Split (as defined below) set forth below in Item 5.03 of this Current Report on Form 8-K is incorporated by reference herein in its entirety.

---

| | |
|:---|:---|
| **Item 5.03** | **Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year.** |

---

On March 6, 2026, ClearSign Technologies Corporation (the "Company") filed an amendment (the "Charter Amendment") to its certificate of incorporation, as amended, with the Secretary of State of Delaware to implement a 1-for-10 reverse stock split, such that every ten (10) shares of the Company's common stock, par value $0.0001 per share (the "common stock"), will be combined into one (1) issued and outstanding share of common stock, with no change in the $0.0001 par value per share (the "Reverse Stock Split").

The Reverse Stock Split and Charter Amendment will be effective at 12:01 a.m., Eastern Time, on March 16, 2026. The Company expects that upon the opening of trading on March 16, 2026, the common stock will begin trading on a post-split basis under CUSIP number 185064201.

In accordance with the terms of the Company's outstanding warrants, equity incentive plans and applicable award agreements, the number of shares of common stock underlying outstanding warrants and equity awards will be proportionately adjusted, and any exercise prices will be proportionately increased, to reflect the Reverse Stock Split. No fractional shares will be outstanding following the Reverse Stock Split. Holders of fractional shares will be entitled to receive, in lieu of any fractional share, the number of shares rounded up to the next whole number at the participant level with the Depository Trust Company.

The foregoing description of the Charter Amendment is not complete and is subject to, and qualified in its entirety by, the complete text of the Charter Amendment, which is filed as Exhibit 3.1 to this Current Report on Form 8-K, and incorporated by reference herein.

---

| | |
|:---|:---|
| **Item 7.01** | **Regulation FD Disclosure.** |

---

On March 10, 2026, the Company issued a press release announcing the Reverse Stock Split. A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K and is incorporated by reference herein.

The information provided under this Item 7.01 of this Current Report on Form 8-K, including Exhibit 99.1 attached hereto, is being furnished and shall not be deemed "filed" for the purposes of Section 18 of the Exchange Act, or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act except as shall be expressly set forth by specific reference in such filing.

---

| | |
|:---|:---|
| **Item 9.01** | **Financial Statements and Exhibits.** |

---

**(d) Exhibits.**

---

| | |
|:---|:---|
| **Exhibit No.** | **Description** |
| [3.1](tm268062d1_ex3-1.htm) | [Certificate of Amendment to Certificate of Incorporation, as amended, of ClearSign Technologies Corporation, filed with the Secretary of State of the State of Delaware on March 6, 2026.](tm268062d1_ex3-1.htm) |
| [99.1\*](tm268062d1_ex99-1.htm) | [Press Release, dated March 10, 2026.](tm268062d1_ex99-1.htm) |
| 104 | Cover Page Interactive Data File (embedded within the Inline XBRL document). |

---

\* Furnished herewith.

**SIGNATURE**

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

Dated: March 10, 2026

---

| | |
|:---|:---|
| **CLEARSIGN TECHNOLOGIES CORPORATION** | **CLEARSIGN TECHNOLOGIES CORPORATION** |
| By: | /s/ Colin James Deller |
| Name: | Colin James Deller |
| Title: | Chief Executive Officer |

---

## Exhibit 3.1

**Exhibit 3.1**

**CERTIFICATE OF AMENDMENT**

**TO THE**

**CERTIFICATE OF INCORPORATION, AS AMENDED, OF CLEARSIGN TECHNOLOGIES CORPORATION**

ClearSign Technologies Corporation, a Delaware corporation (the "<u>Corporation</u>"), does hereby certify that:

FIRST: The Certificate of Incorporation of the Corporation, filed with the Secretary of State of the State of Delaware on June 14, 2023, as amended on June 25, 2024 (collectively referred to as the "<u>Amended Certificate</u>"), is hereby amended by deleting and restating Article IV of the Amended Certificate in its entirety and substituting the following in lieu thereof:

"The total number of shares of capital stock that the Corporation shall have authority to issue is up to 89,500,000 shares, consisting of: (i) 87,500,000 shares of common stock, having a par value of $0.0001 per share (the "<u>Common Stock</u>"); and (ii) 2,000,000 shares of preferred stock, having a par value of $0.0001 per share (the "<u>Preferred Stock</u>").

<u>Reverse Stock Split</u>. Effective as of 12:01 a.m., Eastern Time on March 16, 2026 (the "<u>Effective Time</u>"), each ten (10) outstanding shares of Common Stock outstanding immediately prior to the Effective Time (the "<u>Old Common Stock</u>") shall be combined and converted into one (1) share of Common Stock (the "<u>New Common Stock</u>") based on a ratio of one (1) share of New Common Stock for each ten (10) shares of Old Common Stock. This reverse stock split (the "<u>Reverse Stock Split</u>") of the outstanding shares of Common Stock shall not affect the total number of shares of capital stock, including the Common Stock, that the Company is authorized to issue, which shall remain as set forth under this Article IV.

The Reverse Stock Split shall occur without any further action on the part of the Corporation or the holders of shares of New Common Stock and whether or not certificates representing such holders' shares prior to the Reverse Stock Split are surrendered for cancellation. No fractional interest in a share of New Common Stock shall be deliverable upon the Reverse Stock Split, all of which shares of New Common Stock shall be rounded up to the nearest whole number of such shares, and, in the event any shares of New Common Stock are held through the Depository Trust Company, such shares shall be rounded up at the participant level. No stockholders will receive cash in lieu of fractional shares. All references to "Common Stock" in this Certificate of Incorporation shall be to the New Common Stock."

SECOND: This amendment was duly adopted in accordance with the provisions of Section 242 of the General Corporation Law of the State of Delaware.

THIRD: This Certificate of Amendment shall become effective at 12:01 a.m., Eastern Time on March 16, 2026.

\* \* \* \*

IN WITNESS WHEREOF, the Corporation has caused this Certificate of Amendment to be signed by its officer thereunto duly authorized this 6th day of March, 2026.

---

| | |
|:---|:---|
| ClearSign Technologies Corporation | ClearSign Technologies Corporation |
| By: | /s/ Colin James Deller |
| Name: | Colin James Deller |
| Title: | Chief Executive Officer |

---

## Exhibit 99.1

**Exhibit 99.1**

![](tm268062d1_ex99-1img001.jpg)

**ClearSign Technologies Corporation Announces 1-for-10 Reverse Stock Split to be Effective As of March 16, 2026**

**TULSA, Okla., March 10, 2026 –** ClearSign Technologies Corporation (NASDAQ: CLIR) ("ClearSign" or the "Company"), a leader in advanced combustion and sensing technologies that help industrial operators dramatically reduce emissions, increase efficiency and safety, and support the use of cleaner fuels including hydrogen, today announced a 1-for-10 reverse stock split of its outstanding common stock. The reverse stock split will become effective at 12:01 a.m. ET on March 16, 2026. The common stock is expected to begin trading on a split-adjusted basis on the Nasdaq Capital Market ("Nasdaq") under the same symbol "CLIR" when the market opens on March 16, 2026, with the new CUSIP number 185064201.

The reverse stock split was approved by the Company's stockholders at the Company's special meeting of stockholders held on February 26, 2026. The reverse stock split is intended to increase the per share trading price of the Company's common stock to regain compliance with the $1.00 minimum bid price requirement for continued listing on Nasdaq. The reverse stock split will reduce the number of outstanding shares of the Company's common stock from approximately 54.1 million shares pre-reverse split to approximately 5.41 million shares post-reverse split.

The number of authorized shares of common stock and the par value per share will remain unchanged. As a result of the reverse stock split, every 10 shares of the Company's pre-reverse split common stock will be combined and reclassified into one share of common stock. Proportionate voting rights and other rights of such holders will not be affected by the reverse stock split. No fractional shares will be issued. Stockholders otherwise entitled to a fractional share will receive one whole share rounded up at the participant level with the Depository Trust Company (the "DTC").

In accordance with the terms of the Company's outstanding warrants, equity incentive plans and applicable award agreements, the number of shares underlying outstanding warrants and equity awards will be proportionately adjusted, and any exercise prices will be proportionately increased, to reflect the reverse stock split.

The Company's transfer agent, VStock Transfer, LLC, is acting as exchange agent for the reverse stock split and will send instructions to stockholders of record regarding the exchange of certificates for common stock, if any, for uncertificated shares of common stock. Stockholders owning shares via a broker or other nominee will have their positions automatically adjusted at the participant level with the DTC to reflect the reverse stock split, subject to the brokers' particular processes, and will not be required to take any action in connection with the reverse stock split.

Additional information about the reverse stock split can be found in the Company's Definitive Proxy Statement filed with the Securities and Exchange Commission (the "SEC") on February 2, 2026 (the "Proxy Statement"). The Proxy Statement is available at www.sec.gov or at the Company's website at www.clearsign.com. Additional information regarding this reverse stock split will be included in a Current Report on Form 8-K to be filed by the Company with the SEC on or about March 10, 2026.

**Forward-Looking Statements**

This press release may contain forward-looking statements about the Company, including, without limitation, the Company's expectations regarding anticipated compliance with Nasdaq's minimum bid price rules. You can find many (but not all) of these statements by looking for words such as "approximates," "believes," "hopes," "expects," "anticipates," "estimates," "projects," "intends," "plans," "would," "should," "could," "may," "will" or other similar expressions. While management has based any forward-looking statements included in this press release on its current expectations on the Company's strategy, plans, intentions, performance, or future occurrences or results, the information on which such expectations were based may change. These forward-looking statements rely on a number of assumptions concerning future events and are subject to a number of risks, uncertainties and other factors, many of which are outside of the Company's control, that could cause actual results to materially differ from such statements. Such risks, uncertainties and other factors include, but are not limited to, the Company's ability to regain compliance with Nasdaq's minimum bid price rule, the Company's ability to successfully complete engineering orders for its customers; the Company's ability to generate equipment and installation orders following an initial engineering order from customers; the Company's ability to successfully deliver, install, and meet the performance obligations of the Company's burners in the California market and any other markets the Company may sell products in; the Company's ability to further expand the sale of ultra-low NOx process, flare and boiler burners; the Company's ability to continue expanding its customer base in the refining industry; the Company's ability to effectively compete in the flare industry and to retain its existing customers in such industry; the Company's ability to provide low emissions retrofit solutions based on continuously changing air permit requirements at the federal and state level; the Company's ability to continue innovating and expanding its scope of product and service applications; the Company's ability to expand its engagement with current, and future, customers beyond burner technology and into broader emission and system integration solutions; general business and economic conditions; the performance of management and the Company's employees; the Company's ability to obtain financing; whether the Company's technology will be accepted and adopted and other factors identified in the Company's Annual Report on Form 10-K and other periodic and current reports filed with the SEC and available for review at www.sec.gov. Furthermore, the Company operates in a competitive environment where new and unanticipated risks may arise. Accordingly, investors should not place any reliance on forward-looking statements as a prediction of actual results. The Company disclaims any intention to, and, except as may be required by law, undertakes no obligation to, update or revise forward-looking statements to reflect events or circumstances that subsequently occur or of which the Company hereafter become aware.

**About ClearSign Technologies Corporation**

ClearSign Technologies Corporation designs and develops products and technologies for the purpose of decarbonization and improving key performance characteristics of industrial and commercial systems, including operational performance, energy efficiency, emission reduction, safety, the use of hydrogen as a fuel and overall cost-effectiveness. Our patented technologies, embedded in established OEM products as ClearSign Core™ and ClearSign Eye™ and other sensing configurations, enhance the performance of combustion systems and fuel safety systems in a broad range of markets, including the energy (upstream oil production and down-stream refining), commercial/industrial boiler, chemical, petrochemical, transport and power industries. For more information, please visit <u>www.clearsign.com</u>.

**Investor Relations:**

Matthew Selinger

Firm IR Group for ClearSign

+1 415-572-8152

<u>mselinger@firmirgroup.com</u>