Form 8-K

8-K — ClearSign Technologies Corp

Accession: 0001104659-26-093758

Filed: 2026-08-11

Period: 2026-08-06

CIK: 0001434524

SIC: 3823 (INDUSTRIAL INSTRUMENTS FOR MEASUREMENT, DISPLAY, AND CONTROL)

Item: Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers: Compensatory Arrangements of Certain Officers

Item: Regulation FD Disclosure

Item: Financial Statements and Exhibits

Documents

8-K — tm2622777d1_8k.htm (Primary)

EX-10.1 — EXHIBIT 10.1 (tm2622777d1_ex10-1.htm)

EX-99.1 — EXHIBIT 99.1 (tm2622777d1_ex99-1.htm)

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8-K — FORM 8-K

8-K (Primary)

Filename: tm2622777d1_8k.htm · Sequence: 1

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0001434524

2026-08-06

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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):

August 6, 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 240.13e-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 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of

Certain Officers.

the 2026 annual meeting of stockholders of ClearSign Technologies Corporation (the “Company”) held on June 8, 2026 (the “Annual

Meeting”), the Company’s board of directors (the “Board”) consisted of five directorships, and four directors

stood for re-election at the Annual Meeting, with one directorship remaining vacant. Subsequent to the Annual Meeting, upon recommendation

of the nominating and corporate governance committee of the Board (the “Governance Committee”), the Board appointed Larry

M. Saddler to serve as a director, effective as of August 6, 2026 (the “Effective Date”), to fill such vacancy on the Board.

Mr.

Saddler, age 76, brings over 40 years of engineering, technology, and operations leadership experience in the energy and industrial sectors,

gained exclusively in various roles at ExxonMobil Holdings Corporation (NYSE: XOM) (formerly known as “Exxon Mobil Corporation”)

(“ExxonMobil”). Mr. Saddler served as Global Technology Sponsor for Heat Transfer at ExxonMobil from February 2013 until his

retirement in February 2021, where he was responsible for, among other things, the functional testing, application, startup and support

of ultra-low NOx projects and new technologies in the fired and unfired heat transfer fields, as well as the oversight of global fleet

management of the safety, environmental, reliability and margin performance of ExxonMobil’s fired equipment asset class. Prior to

that role, Mr. Saddler served as Fired Equipment Lead at ExxonMobil from July 2008 to February 2013, where he provided regional support

across the Americas for plant operations, turnarounds, technology applications, capital projects and mentoring less experienced engineers.

Further, from July 1999 to July 2008, Mr. Saddler served as a Fired Equipment Engineer at ExxonMobil, focusing on the development, testing

and technical readiness of new ultra-low NOx burner technologies in support of a large capital project spanning dozens of pieces of fired

equipment. Prior to such roles, Mr. Saddler served in other engineering roles at ExxonMobil, from July 1981 to July 1999. Mr. Saddler

received a Bachelor of Science in Mechanical Engineering from Clemson University.

connection with his appointment to the Board, Mr. Saddler received an offer letter from the Company, effective as of the Effective Date

(the “Offer Letter”), setting forth the terms of Mr. Saddler’s services as a director and his compensation arrangement,

which he accepted on such date. Pursuant to the Offer Letter and in accordance with the Company’s non-executive director compensation

policy (the “Director Compensation Policy”), Mr. Saddler will receive (i) cash compensation of $60,000 annually, payable in

quarterly installments in arrears on the last day of the fiscal quarter in which the service occurred, with the amount for the first quarter

of service prorated based on Mr. Saddler’s start date, provided that Mr. Saddler may elect to receive all or a portion of such cash

compensation in the form of restricted stock units (“RSUs”) with the fair market value based on the closing price of the Company’s

common stock on the date of grant; and (ii) non-statutory stock option grants with an aggregate fair market value of $40,000 annually,

issued in quarterly installments in arrears on the last day of each fiscal quarter in which the service occurred, with the amount for

the first quarter of service prorated based on Mr. Saddler’s start date. Any RSUs and stock options granted under the Director Compensation

Policy and in accordance with the Offer Letter will be issued under the Company’s Amended and Restated 2021 Equity Incentive Plan.

In addition, pursuant to the Offer Letter, Mr. Saddler is entitled to supplemental director compensation with respect to certain outstanding,

unvested RSUs of his prior employer held by Mr. Saddler that were received as part of his prior employment’s compensation (the “Covered

RSUs”), pursuant to which, to the extent applicable, the Company has agreed to make future cash payments to Mr. Saddler equal to

the value of any Covered RSUs that are forfeited or cancelled in connection with his appointment to or service on the Board (the “Make-Whole

Payments”), subject to Mr. Saddler’s continued service as a director through the applicable scheduled vesting date of each

such Covered RSU (each, a “Scheduled Vesting Date”), except in the case of his earlier death or disability. The Make-Whole

Payments will be payable no later than 30 days after each Scheduled Vesting Date, and in all events by March 15 of the calendar year following

the year in which a Scheduled Vesting Date occurs, if any.

The

foregoing description of the Offer Letter does not purport to be a complete description of the rights and obligations of the parties thereunder

and is qualified in its entirety by reference to the Offer Letter, which is included as Exhibit 10.1 to this Current Report on Form 8-K.

connection with his appointment to the Board, Mr. Saddler also entered into the Company’s standard form of indemnification agreement,

the form of which was filed as Exhibit 10.1 to the Company’s Quarterly Report on Form 10-Q filed with the Securities and Exchange

Commission on August 14, 2023.

There

are no other arrangements or understandings between Mr. Saddler and any other person pursuant to which he was selected as a director.

There are no family relationships between Mr. Saddler and any of the Company’s officers and directors, and there is no transaction

between the Company and Mr. Saddler that is required to be disclosed pursuant to Item 404(a) of Regulation S-K.

Item 7.01

Regulation FD Disclosure.

August 11, 2026, the Company issued a press release announcing Mr. Saddler’s appointment to the Board, as described in Item 5.02.

copy of the press release is being furnished as Exhibit 99.1 to this Current Report on Form 8-K. The information in this Item 7.01 of

this Current Report on Form 8-K, including Exhibit 99.1, shall not be deemed to be “filed” for purposes of Section 18 of the

Securities Exchange Act of 1934, as amended (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, whether

made before or after the date hereof and regardless of any general incorporation language in such filings, except to the extent expressly

set forth by specific reference in such a filing.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits.

Exhibit No.

Description

10.1+

Offer Letter, effective as of August 6, 2026, by and between ClearSign Technologies Corporation and Larry M. Saddler.

10.2*+

Form of Indemnification Agreement (incorporated by reference to Exhibit 10.1 to the Company’s Quarterly Report on Form 10-Q, filed with the Securities and Exchange Commission on August 14, 2023).

99.1**

Press Release, dated August 11, 2026.

104

Cover Page Interactive Data File (embedded within the Inline XBRL document).

* Previously filed.

** Furnished herewith.

+ Indicates a management contract or compensatory plan, contract or

arrangement.

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: August 11, 2026

CLEARSIGN TECHNOLOGIES CORPORATION

By:

/s/ Colin James Deller

Name:

Colin James Deller

Title:

Chief Executive Officer

EX-10.1 — EXHIBIT 10.1

EX-10.1

Filename: tm2622777d1_ex10-1.htm · Sequence: 2

Exhibit 10.1

August 6, 2026

Re: Board of Directors of ClearSign Technologies

Corporation - Offer Letter

Dear Mr. Larry M. Saddler:

On behalf of ClearSign Technologies

Corporation (the “Company,” “ClearSign,” “we,” “our” or “us”)

and our Board of Directors (“Board”), I am pleased to offer you a position as a member of our Board. We look forward

to working with you on the Board. Should you choose to accept this position as a member of the Board, including service as a member of

any committees of the Board, as may be determined by the Board at a later time, this letter shall constitute an agreement (the “Agreement”)

between you and the Company and contains all the terms and conditions relating to the services to be provided.

1.       Term.

This Agreement shall be through the date of the next annual shareholders’ meeting expected in early June 2027 and commencing on

the date you and the Company execute this Agreement although your actual start date can be mutually agreed to be on that date, or a later

date. The position shall be up for re-election each year at the annual shareholders’ meeting and upon re-election, the terms and

provisions of this Agreement shall remain in full force and effect. You also agree to resign from the Board of Directors if requested

by a majority of the then-sitting members of the Board. This Agreement shall be in effect as long as you are a director on the Board.

2.       Services.

You shall render services in the area of managing or directing the Company’s property, affairs and business (hereinafter, your “Duties”).

You shall consult with other members of the Board at meetings held quarterly, or more regularly if required, in locations determined by

the Chief Executive Officer of the Company. You agree that your relationship with the Company will be that of a director and not that

of an employee. Nothing in this Agreement is intended to replace, supersede or diminish any of your duties to the Company as a director

under state law. You also agree to comply with all federal and state securities laws as well as Company policies, as applicable.

3.       Services

for Others. You are free to represent or perform services for other persons during the term of this Agreement. However, you agree

that you do not presently perform and do not intend to perform, during the term of this Agreement, similar Duties, consulting or other

services for companies whose businesses are or would be, in any way, in conflict or competitive with the Company (except for companies

previously disclosed by you to the Company in writing). Should you propose to perform similar Duties, consulting or other services for

any such company, you agree to notify the Company in writing in advance (specifying the name of the organization for whom you propose

to perform such services) and to provide sufficient information to the Company to allow it to determine if the performance of such services

would conflict with areas of interest to the Company.

4.       Compensation.

Director Compensation. In consideration for your service as a member of the Board, you will receive annual compensation in accordance

with the Company’s non-employee director compensation policy (as it may be amended from time to time, the “Director Compensation

Policy”), pursuant to which you will receive (i) cash compensation of $60 thousand, payable in quarterly installments in arrears

on the last day of the fiscal quarter in which the service occurred, with the amount prorated if the service started after the start of

the fiscal quarter; provided, however, that, pursuant to the Director Compensation Policy, you may elect to receive all or a portion of

your cash compensation in the form of restricted stock units (“RSUs”), which fair market value will be based on the

closing price of ClearSign’s common stock, as reported on The Nasdaq Stock Market LLC on the date of grant; and (ii) non-statutory

stock option (“Stock Options”) grants with an aggregate fair market value of $40 thousand annually, issued in quarterly

installments in arrears on the last day of each fiscal quarter in which the service occurred, with the amount prorated if the service

started after the start of the fiscal quarter. RSUs and Stock Options issued in accordance with the Director Compensation Policy will

be issued under the Company’s Amended and Restated 2021 Equity Incentive Plan (the “Plan”). Further, RSUs, if

any are issued in accordance with the Director Compensation Policy, will vest upon death, departure from the board or a “change

of control,” as such term is defined in the applicable award agreement related to such RSU, as determined by the Compensation Committee

of the Board and in accordance with the Plan. The Company will also reimburse you for reasonable expenses incurred in connection with

the performance of your Duties as a director in accordance with the Company’s expense policy then in effect.

Supplemental Director Compensation – ExxonMobil Equity Make-Whole.

Covered Awards. You currently hold the outstanding, unvested restricted stock units set forth in Schedule A

hereto (the “Covered RSUs”), which are scheduled to vest as set forth therein (each such date, a “Scheduled

Vesting Date”). Each Covered RSU is settled into one (1) share of common stock of the issuer of the Covered RSUs (the “RSU

Issuer”) following the applicable Scheduled Vesting Date of the Covered RSUs, in accordance with the terms and conditions of

the applicable RSU Issuer’s equity incentive plan(s), and as adjusted for any stock split, reverse split, stock dividend, spin-off,

recapitalization, or similar corporate transaction.

ii.

Make-Whole Cash Payment. If any Covered RSUs are forfeited or cancelled in connection with your appointment to or service

on the Board (a “Forfeiture”), then, subject to Section 4(b)(iv) herein, ClearSign will pay you cash in an amount equal

to the number of forfeited Covered RSUs multiplied by the closing price per share of common stock of the RSU Issuer, as reported on the

New York Stock Exchange, on the applicable Scheduled Vesting Date (or, if not a trading day, the immediately preceding trading day) (each

such cash payment, a “Make-Whole Payment,” and collectively, the “Make-Whole Payments”).

iii.

Taxes. You understand and agree that you (and not the Company) shall be responsible for your own federal, state, local or

foreign tax liability and any of your other tax consequences that may arise as a result of the receipt of any Make-Whole Payment contemplated

by this Section 4(b) (such taxes, the “Taxes”).

iv.

Continued Service Condition. ClearSign’s obligation to pay a Make-Whole Payment with respect to any Covered RSU is

conditioned on your continued service as a ClearSign director through the applicable Scheduled Vesting Date; provided, however, that such

condition will be deemed satisfied if your service ends before a Scheduled Vesting Date due to your earlier death or disability.

Timing. ClearSign will pay each Make-Whole Payment, if any, in a lump sum no later than thirty (30) days after the applicable

Scheduled Vesting Date, and in all events by March 15 of the calendar year following the year in which a Scheduled Vesting Date occurs.

vi.

Evidence. As a further condition to receive a Make-Whole Payment, you will provide reasonable documentation evidencing a

Forfeiture and the number of Covered RSUs forfeited or cancelled (e.g., the applicable Covered RSU award agreement or equity incentive

plan provision and a forfeiture notice or account statement from the RSU Issuer).

vii.

Non-Duplication. Each Make-Whole Payment will be reduced by the dollar value of any Covered RSUs that ultimately vest and

settle, or any other consideration you receive in respect of the Covered RSUs from the RSU Issuer, in each case before Taxes.

5.       D&O

Insurance Policy. You will be entitled to coverage under our Directors and Officers liability insurance as then in effect.

6.       Assignment.

Because of the personal nature of the services to be rendered by you, this Agreement may not be assigned by you. The Company shall be

free to transfer any of its rights under this Agreement to any affiliate or third party.

7.       Confidential

Information; Non-Disclosure. In consideration of your access to the premises of the Company and your access to certain Confidential

Information of the Company, in connection with your business relationship with the Company, you hereby represent and agree as follows:

a.       Definition.

For purposes of this Agreement the term “Confidential Information” means:

i.        Any

information which the Company possesses that has been created, discovered or developed by or for the Company, and which has or could have

commercial value or utility in the business in which the Company is engaged; or

ii.       Any

information that is related to the business of the Company and is generally not known by non-Company personnel.

iii.      By

way of illustration, but not limitation, Confidential Information includes trade secrets and any information concerning products, processes,

formulas, designs, inventions (whether or not patentable or registrable under copyright or similar laws, and whether or not reduced to

practice), discoveries, concepts, ideas, improvements, techniques, methods, research, development and test results, specifications, data,

know-how, software, formats, marketing plans, and analyses, business plans and analyses, strategies, forecasts, customer and supplier

identities, characteristics and Agreements.

b.       Exclusions.

Notwithstanding the foregoing, the term Confidential Information shall not include:

i.        Any

information which becomes generally available to the public other than as a result of a breach of the confidentiality portions of this

Agreement, or any other Agreement requiring confidentiality between the Company and you;

ii.       Information

received from a third party in rightful possession of such information who is not restricted from disclosing such information; and

iii.      Information

known by you prior to receipt of such information from the Company, which prior knowledge can be documented.

8.       Documents.

You agree that, without the express written consent of the Company, you will not remove from the Company's premises, any notes, formulas,

programs, data, records, machines or any other documents or items which in any manner contain or constitute Confidential Information,

nor will you make reproductions or copies of same. In the event you receive any such documents or items by personal delivery from any

duly designated or authorized personnel of the Company, you shall be deemed to have received the express written consent of the Company.

In the event that you receive any such documents or items, other than through personal delivery as described in the preceding sentence,

you agree to inform the Company promptly of your possession of such documents or items. You agree to promptly return any such documents

or items, along with any reproductions or copies to the Company upon the Company's demand or upon termination of this Agreement or your

departure from the Board.

9.       Non-Disparagement.

You agree to forbear from making, causing to be made, publishing, ratifying or endorsing any and all disparaging remarks, derogatory statements

or comments to any third party with respect to the Company and its affiliates, including, without limitation, the Company’s parent,

subsidiaries, officers, directors and employees (collectively, “Company Parties”). Further, you hereby agree to forbear

from making any public or non-confidential statement with respect to any of the Company Parties. The duties and obligations of this paragraph

9 shall continue following the termination of this Agreement.

10.     Non-Solicitation.

You agree and covenant not to directly or indirectly solicit, hire, or recruit for your own benefit or the benefit of any other person,

or so attempt to solicit, hire, or recruit, any employee of the Company, or induce any other employee of the Company to terminate their

employment for two (2) years immediately following your cessation of services to the Company, regardless of the reason. This non-solicitation

paragraph explicitly covers all forms of oral, written, or electronic communication, including, but not limited to, communications by

email, regular mail, express mail, telephone, fax, instant message, and social media, including, but not limited to, Facebook, LinkedIn,

Instagram, and Twitter, and any other social media platform, whether or not in existence at the time of entering into this Agreement.

11.     No

Disclosure. You agree that you will hold in trust and confidence all Confidential Information and will not disclose to others, directly

or indirectly, any Confidential Information or anything relating to such information without the prior written consent of the Company,

except as maybe necessary in the course of this business relationship with the Company. You further agree that you will not use any Confidential

Information without the prior written consent of the Company, except as may be necessary in the course of your business relationship with

the Company, and that the provisions of this paragraph 11 shall survive termination of this Agreement.

12.     Termination.

This Agreement shall terminate in the event of your resignation or termination as a director, or your refusal to stand for re-election

or decision not to be nominated or if you are not re-elected for additional terms as a director, effective on the date of your departure

from the Board.

13.    Entire

Agreement; Amendment; Waiver. Other than any requirements and duties under applicable law, this Agreement expresses the entire understanding

with respect to the subject matter hereof and supersedes and terminates any prior oral or written Agreements with respect to the subject

matter hereof. Any term of this Agreement may be amended and observance of any term of this Agreement may be waived only with the written

consent of the parties hereto. Waiver of any term or condition of this Agreement by any party shall not be construed as a waiver of any

subsequent breach or failure of the same term or condition or waiver of any other term or condition of this Agreement. The failure of

any party at any time to require performance by any other party of any provision of this Agreement shall not affect the right of any such

party to require future performance of such provision or any other provision of Agreement.

14.     Enforcement.

a.       Applicable

Law. This Agreement and the rights and remedies of each party arising out of or relating to this Agreement (including, without limitation,

equitable remedies) shall be solely governed by, interpreted under, and construed and enforced in accordance with the laws (without regard

to the conflicts of law principles thereof) of the State of Delaware, as if this Agreement were made, and as if its obligations are to

be performed, wholly within the State of Oklahoma.

b.       Consent

to Jurisdiction and Venue. Any action or proceeding arising out of or relating to this Agreement shall be filed in and heard and litigated

solely before the state or federal courts of Oklahoma within Tulsa County.

c.       Attorneys’

Fees. If court proceedings are required to enforce any provision of this Agreement, the substantially prevailing or successful party

shall be entitled to an award of the reasonable and necessary expenses of litigation, including reasonable attorneys’ fees.

appreciate your willingness to serve on our Board and look forward to working with you to serve the Company together. Please indicate

your acceptance by signing and returning the enclosed copy of this letter.

Very truly yours,

ClearSign Technologies Corporation

/s/ Colin James Deller

Dr. Colin James Deller, Chief Executive Officer

ACCEPTED AND AGREED:

/s/ Larry M. Saddler

Name: Larry M. Saddler

Date: August 6, 2026

SCHEDULE A

COVERED RSU SCHEDULE

Name of RSU Issuer

Number of Covered RSUs

Vesting Date

ExxonMobil Holdings Corporation (NYSE: XOM)

250

November 26, 2026

ExxonMobil Holdings Corporation (NYSE: XOM)

150

November 24, 2027

EX-99.1 — EXHIBIT 99.1

EX-99.1

Filename: tm2622777d1_ex99-1.htm · Sequence: 3

Exhibit 99.1

ClearSign Board

of Directors Appoints Former ExxonMobil Global Technology Leader Larry Saddler

TULSA, Okla., August 11, 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 support the use of cleaner

fuels including hydrogen, today announces that industry veteran Larry Saddler has been appointed to fill the vacant directorship on the

Company’s Board of Directors (the “Board”).

“We are very excited to have Larry

join the Board,” said Jim Deller, Ph.D., Chief Executive Officer of ClearSign. “I have known Larry for many years. He has

extensive knowledge, experience and relationships that he has developed during an eminent career of technical leadership in the refining

industry, and I believe he will be a valuable addition to our Board.”

“I have followed the evolution

of ClearSign’s technology for many years and have been consistently impressed by its ingenuity and the value it offers,”

said Larry Saddler. “As a member of the Board, I look forward to leveraging my experience, industry expertise, and professional

relationships to help the ongoing promotion and adoption of ClearSign’s technology and to contribute to the Company's strategic

growth and creation of long-term stockholder value.”

Mr. Saddler is a retired ExxonMobil

executive that has nearly 40 years of experience in heat transfer technology, fired equipment engineering, and global operations support.

Throughout a distinguished career, he served in progressively senior technical leadership roles at ExxonMobil, including as Global Technology

Sponsor for Heat Transfer, where he was responsible for, among other things, the oversight of the global fleet management of fired equipment’s

technology, safety, environmental, reliability and margin performance.

Mr. Saddler also played a key role in

advancing next-generation Ultra Low-NOx burner technology, overseeing its development, testing, startup, and implementation across major

capital projects. His expertise spans technology application, commissioning, plant operations support, turnaround planning, and engineering

integration across global refining and petrochemical facilities.

Widely respected throughout the industry,

Mr. Saddler built strong partnerships with equipment owners, engineering service providers, and technology organizations worldwide. In

addition to providing technical leadership across the Americas, he mentored and developed the next generation of engineers while helping

drive innovation in heat transfer systems and emissions reduction technologies.

Mr. Saddler, a graduate of Clemson University

with a Bachelor of Science in Mechanical Engineering, dedicated his entire professional career to ExxonMobil, serving in engineering

and leadership positions across the United States, Thailand, and the United Kingdom before retiring in 2021.

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 www.clearsign.com.

For further information:

Investor Relations:

Matthew Selinger

Firm IR Group for ClearSign

+1 415-572-8152

mselinger@firmirgroup.com

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For the EDGAR submission types of Form 8-K: the date of the report, the date of the earliest event reported; for the EDGAR submission types of Form N-1A: the filing date; for all other submission types: the end of the reporting or transition period. The format of the date is YYYY-MM-DD.

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No definition available.

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dei_DocumentPeriodEndDate

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xbrli:dateItemType

Balance Type:

Period Type:

duration

- Definition

The type of document being provided (such as 10-K, 10-Q, 485BPOS, etc). The document type is limited to the same value as the supporting SEC submission type, or the word 'Other'.

+ References

No definition available.

+ Details

Name:

dei_DocumentType

Namespace Prefix:

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Data Type:

dei:submissionTypeItemType

Balance Type:

Period Type:

duration

- Definition

Address Line 1 such as Attn, Building Name, Street Name

+ References

No definition available.

+ Details

Name:

dei_EntityAddressAddressLine1

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

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- Definition

Name of the City or Town

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No definition available.

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Name:

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Namespace Prefix:

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Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

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- Definition

Code for the postal or zip code

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No definition available.

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Name:

dei_EntityAddressPostalZipCode

Namespace Prefix:

dei_

Data Type:

xbrli:normalizedStringItemType

Balance Type:

Period Type:

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- Definition

Name of the state or province.

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No definition available.

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Name:

dei_EntityAddressStateOrProvince

Namespace Prefix:

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Data Type:

dei:stateOrProvinceItemType

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Period Type:

duration

- Definition

A unique 10-digit SEC-issued value to identify entities that have filed disclosures with the SEC. It is commonly abbreviated as CIK.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

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Name:

dei_EntityCentralIndexKey

Namespace Prefix:

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Data Type:

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Balance Type:

Period Type:

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- Definition

Indicate if registrant meets the emerging growth company criteria.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

+ Details

Name:

dei_EntityEmergingGrowthCompany

Namespace Prefix:

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Data Type:

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duration

- Definition

Commission file number. The field allows up to 17 characters. The prefix may contain 1-3 digits, the sequence number may contain 1-8 digits, the optional suffix may contain 1-4 characters, and the fields are separated with a hyphen.

+ References

No definition available.

+ Details

Name:

dei_EntityFileNumber

Namespace Prefix:

dei_

Data Type:

dei:fileNumberItemType

Balance Type:

Period Type:

duration

- Definition

Two-character EDGAR code representing the state or country of incorporation.

+ References

No definition available.

+ Details

Name:

dei_EntityIncorporationStateCountryCode

Namespace Prefix:

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Data Type:

dei:edgarStateCountryItemType

Balance Type:

Period Type:

duration

- Definition

The exact name of the entity filing the report as specified in its charter, which is required by forms filed with the SEC.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

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Name:

dei_EntityRegistrantName

Namespace Prefix:

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xbrli:normalizedStringItemType

Balance Type:

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- Definition

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b-2

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Name:

dei_EntityTaxIdentificationNumber

Namespace Prefix:

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Data Type:

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Period Type:

duration

- Definition

Local phone number for entity.

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No definition available.

+ Details

Name:

dei_LocalPhoneNumber

Namespace Prefix:

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Data Type:

xbrli:normalizedStringItemType

Balance Type:

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 13e

-Subsection 4c

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Name:

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Namespace Prefix:

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Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14d

-Subsection 2b

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Name:

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Namespace Prefix:

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Data Type:

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Balance Type:

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- Definition

Title of a 12(b) registered security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection b

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Name:

dei_Security12bTitle

Namespace Prefix:

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Data Type:

dei:securityTitleItemType

Balance Type:

Period Type:

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- Definition

Name of the Exchange on which a security is registered.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 12

-Subsection d1-1

+ Details

Name:

dei_SecurityExchangeName

Namespace Prefix:

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Data Type:

dei:edgarExchangeCodeItemType

Balance Type:

Period Type:

duration

- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as soliciting material pursuant to Rule 14a-12 under the Exchange Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Exchange Act

-Number 240

-Section 14a

-Subsection 12

+ Details

Name:

dei_SolicitingMaterial

Namespace Prefix:

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Data Type:

xbrli:booleanItemType

Balance Type:

Period Type:

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- Definition

Trading symbol of an instrument as listed on an exchange.

+ References

No definition available.

+ Details

Name:

dei_TradingSymbol

Namespace Prefix:

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Data Type:

dei:tradingSymbolItemType

Balance Type:

Period Type:

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- Definition

Boolean flag that is true when the Form 8-K filing is intended to satisfy the filing obligation of the registrant as written communications pursuant to Rule 425 under the Securities Act.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Securities Act

-Number 230

-Section 425

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