# EDGAR Filing Document

**Accession Number:** 0001434524
**File Stem:** 0001558370-25-008617
**Filing Date:** 2025-6
**Character Count:** 2463
**Document Hash:** bbea6b245f43b17f5ad93c4364a31f40
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001558370-25-008617.hdr.sgml**: 20250613

**ACCESSION NUMBER**: 0001558370-25-008617

**CONFORMED SUBMISSION TYPE**: DEFA14A

**PUBLIC DOCUMENT COUNT**: 3

**FILED AS OF DATE**: 20250613

**DATE AS OF CHANGE**: 20250613

**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:** DEFA14A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-35521
- **FILM NUMBER:** 251046621

**BUSINESS ADDRESS:**
- **STREET 1:** 8023 E. 63RD PLACE, SUITE 101
- **CITY:** TULSA
- **STATE:** OK
- **ZIP:** 74133
- **BUSINESS PHONE:** (918) 236-6461

**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

**SCHEDULE 14A**

**(RULE 14a-101)**

**INFORMATION REQUIRED IN PROXY STATEMENT**

**SCHEDULE 14A INFORMATION**

**Proxy Statement Pursuant to Section 14(a) of the**

**Securities Exchange Act of 1934**

Filed by the Registrant ⌧

Filed by a Party other than the Registrant ◻

Check the appropriate box:

---

| | |
|:---|:---|
| ◻ | Preliminary Proxy Statement  |
| ◻ | Confidential, For Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) |
| ◻ | Definitive Proxy Statement |
| ⌧ | Definitive Additional Materials |
| ◻ | Soliciting Material Pursuant to §240.14a-12 |

---

**ClearSign Technologies Corporation**

(Name of Registrant as Specified in Its Charter)

(Name of Person(s) Filing Proxy Statement, if Other Than the Registrant)

Payment of Filing Fee (Check the appropriate box):

---

| | | |
|:---|:---|:---|
| ⌧ | ⌧ | No fee required. |
| ◻ | Fee paid previously with preliminary materials. | Fee paid previously with preliminary materials. |
| ◻ | Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11. | Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11. |

---

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