Form 8-K
8-K — ClearSign Technologies Corp
Accession: 0001104659-26-086099
Filed: 2026-07-23
Period: 2026-07-21
CIK: 0001434524
SIC: 3823 (INDUSTRIAL INSTRUMENTS FOR MEASUREMENT, DISPLAY, AND CONTROL)
Item: Entry into a Material Definitive Agreement
Item: Unregistered Sales of Equity Securities
Item: Regulation FD Disclosure
Item: Financial Statements and Exhibits
Documents
8-K — tm2621046d1_8k.htm (Primary)
EX-10.1 — EXHIBIT 10.1 (tm2621046d1_ex10-1.htm)
EX-10.2 — EXHIBIT 10.2 (tm2621046d1_ex10-2.htm)
EX-99.1 — EXHIBIT 99.1 (tm2621046d1_ex99-1.htm)
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8-K — FORM 8-K
8-K (Primary)
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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):
July 21, 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 1.01
Entry into a Material Definitive Agreement.
Newbridge Securities
Corporation Waiver
On
July 21, 2026, ClearSign Technologies Corporation (the “Company”) received a waiver (the “Waiver”) from Newbridge
Securities Corporation (the “Underwriter”) of certain restrictions on sales of the Company’s capital stock set forth
in Section 3.16.1 of that certain Underwriting Agreement, dated as of May 28, 2026, between the Company and the Underwriter (the “Underwriting
Agreement”). Pursuant to the Waiver, the Underwriter irrevocably and unconditionally waived the restrictions set forth in Section
3.16.1 of the Underwriting Agreement, including the restrictions on the Company’s ability to (a) offer, pledge, sell, contract to
sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase,
lend, or otherwise transfer or dispose of, directly or indirectly, any shares of capital stock of the Company or any securities convertible
into or exercisable or exchangeable for shares of capital stock of the Company, (b) file or cause to be filed any registration statement
with the Securities and Exchange Commission relating to the offering of any such securities, and (c) enter into any swap or other arrangement
that transfers to another, in whole or in part, any of the economic consequences of ownership of capital stock of the Company, in each
case solely to the extent necessary to permit the Private Sale (as defined below) to Otter Capital LLC, a California limited liability
company (the “Investor”), as described below in Item 1.01 of this Current Report on Form 8-K under “Stock Purchase
Agreement.”
The
Waiver is effective as of July 21, 2026 and will continue through and including the earlier of (i) the consummation of the Private Sale
and (ii) July 31, 2026. Except as expressly set forth in the Waiver, the terms and provisions of the Underwriting Agreement remain unmodified
and in full force and effect.
The
foregoing description of the terms of the Waiver does not purport to be complete and is qualified in its entirety by the full text of
the Waiver attached as Exhibit 10.1 to this Current Report on Form 8-K, which is incorporated by reference herein.
Stock Purchase Agreement
On
July 21, 2026, in connection with the receipt of the Waiver, the Company entered into a Stock Purchase Agreement (the “Purchase
Agreement”) with the Investor, an existing stockholder of the Company that, as of the date hereof, holds more than 5% of the issued
and outstanding shares of the Company’s common stock, par value $0.0001 per share (the “Common Stock”), pursuant to
which the Company sold and the Investor purchased 500,000 shares of Common Stock (the “Shares”) at a price per share of $3.54,
for aggregate gross proceeds of $1,770,000 (the “Private Sale”).
The
Shares sold pursuant to the Purchase Agreement were issued as restricted securities as defined in Rule 144 of the Securities Act of 1933,
as amended (the “Securities Act”), and do not contain any registration rights. The Company intends to use the net proceeds
from the Private Sale for general corporate purposes, including working capital, research and development, and marketing and sales.
The
foregoing description of the terms of the Purchase Agreement does not purport to be complete and is qualified in its entirety by the full
text of the Purchase Agreement attached as Exhibit 10.2 to this Current Report on Form 8-K, which is incorporated by reference
herein.
Item 3.02
Unregistered Sales of Equity Securities.
To
the extent required, the disclosure under Item 1.01 above is hereby incorporated in this Item 3.02 by reference.
The
Shares were issued pursuant to an exemption from registration provided by Section 4(a)(2) and/or Rule 506 of Regulation
D promulgated under the Securities Act because such issuance did not involve a public offering, the Investor took the Shares
for investment and not resale, the Company took appropriate measures to restrict transfer, and the Investor is a sophisticated investor.
The Shares are subject to transfer restrictions, and the book-entry records evidencing the securities contain an appropriate legend stating
that such securities have not been registered under the Securities Act and may not be offered or sold absent registration or
pursuant to an exemption therefrom. The Shares were not registered under the Securities Act and such securities may not be offered
or sold in the United States absent registration or an exemption from registration under the Securities Act and any applicable
state securities laws.
Item 7.01 Regulation FD Disclosure.
On
July 23, 2026, the Company issued a press release announcing the Private Sale. 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 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 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
10.1*
Waiver Agreement, dated as of July 21, 2026, by and between ClearSign Technologies Corporation and Newbridge Securities Corporation.
10.2*#
Stock Purchase Agreement, dated as of July 21, 2026.
99.1**
Press Release, dated July 23, 2026.
104*
Cover Page Interactive Data File (embedded within the Inline XBRL document).
* Filed herewith.
** Furnished herewith.
# The exhibit to this agreement has been omitted pursuant to Item 601(a)(5)
of Regulation S-K. A copy of any omitted exhibit will be furnished to the Securities and Exchange Commission upon request.
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: July 23, 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: tm2621046d1_ex10-1.htm · Sequence: 2
Exhibit 10.1
July 21, 2026
ClearSign Technologies Corporation
8023 East 63rd Place, Suite 101
Tulsa, OK 74133
Attention: Colin
James Deller, Chief Executive Officer
Re: Waiver Regarding
Restrictions on Sales of Capital Stock
Dear Dr. Deller:
Reference
is made to that certain Underwriting Agreement, dated as of May 28, 2026 (the “Agreement”), between ClearSign Technologies
Corporation, a Delaware corporation (the “Company”), and Newbridge Securities Corporation (the “Underwriter”).
Capitalized terms used but not otherwise defined herein shall have the meanings ascribed to them in the Agreement.
Reference is further made to that certain proposed
investment in the Company by Otter Capital LLC, a California limited liability company, pursuant to a stock purchase agreement to be entered
into by the Company and Otter Capital LLC on substantially the terms currently contemplated by the Company and Otter Capital LLC as of
the date hereof (the “Otter Transaction”).
In consideration of the mutual agreements set
forth herein and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the Underwriter
hereby irrevocably and unconditionally waives the restrictions set forth in Section 3.16.1 of the Agreement, including clauses (a), (b)
and (c) thereof, solely to the extent necessary to permit the Otter Transaction, including, without limitation, that the Company will
not (a) offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant
any option, right or warrant to purchase, lend, or otherwise transfer or dispose of, directly or indirectly, any shares of capital stock
of the Company or any securities convertible into or exercisable or exchangeable for shares of capital stock of the Company, (b) file
or cause to be filed any registration statement with the Commission relating to the offering of any such securities, or (c) enter into
any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of capital
stock of the Company.
This waiver shall become effective only upon execution
and delivery of this letter by each of the parties hereto (the “Effective Date”) and shall continue from the Effective
Date through and including the earlier of (i) the consummation of the closing of the Otter Transaction and (ii) July 31, 2026.
Upon effectiveness, this waiver shall be irrevocable
and unconditional and shall not be subject to withdrawal, revocation, modification or rescission by the Underwriter for any reason. This
waiver shall be binding upon the Underwriter and its successors and assigns and shall inure to the benefit of the Company, its Subsidiary,
their respective successors and assigns, and any counterparty to the transaction covered hereby.
Except as expressly modified by this waiver letter,
the terms and provisions of the Agreement shall remain unmodified and in full force and effect. This waiver letter shall be governed by
and construed in accordance with the laws of the State of New York without regard to principles of conflict of laws.
Please acknowledge your receipt of this waiver
letter and your agreement to the foregoing by executing below.
Very truly yours,
NEWBRIDGE SECURITIES CORPORATION
By:
/s/ Chad D. Champion
Name:
Chad D. Champion
Title:
Senior Managing Director, Head of Investment Banking and Capital Markets
Acknowledged and agreed to this on
July 21, 2026
CLEARSIGN
TECHNOLOGIES CORPORATION
By:
/s/ Colin James Deller
Name:
Colin James Deller
Title:
Chief Executive Officer
EX-10.2 — EXHIBIT 10.2
EX-10.2
Filename: tm2621046d1_ex10-2.htm · Sequence: 3
Exhibit 10.2
STOCK PURCHASE AGREEMENT
This STOCK PURCHASE AGREEMENT
(this “Agreement”) is entered into as of July 21, 2026, by and between ClearSign Technologies Corporation, a Delaware
corporation (the “Company”) and Otter Capital LLC, a California limited liability company (the “Purchaser”).
WHEREAS, the Purchaser
desires to purchase, and the Company desires to sell, an aggregate of 500,000 shares (the “Shares”) of the Company’s
common stock, par value $0.0001 per share (the “Common Stock”), upon the terms and conditions hereof; and
WHEREAS, subject to
the terms and conditions set forth in this Agreement and pursuant to an exemption from the registration requirements of Section 5 of the
Securities Act (as defined below) contained in Section 4(a)(2) thereof and/or Regulation D thereunder, the Company desires to issue and
sell the Shares to the Purchaser, and Purchaser desires to purchase the Shares from the Company, as more fully described in this Agreement.
NOW, THEREFORE, in
consideration of the premises and the mutual agreements herein contained, the Purchaser and the Company hereby agree as follows:
SECTION 1: SALE OF THE SHARES
1.1 Sale of the Shares.
Subject to the terms and conditions hereof, at the Closing, the Company will sell to the Purchaser and the Purchaser will purchase from
the Company, the Shares at a price per share of $3.54 for an aggregate purchase price equal to $1,770,000 (the “Purchase Price”).
SECTION 2: CLOSING DATE; DELIVERY
2.1 Closing Date. The
closing of the purchase and sale of the Shares (the “Closing”) shall occur on July 22, 2026. At the Closing, the Company
shall deliver, or cause to be delivered, the items set forth in Section 2.2(a) to the Purchaser, and the Purchaser shall deliver,
or cause to be delivered, the items set forth in Section 2.2(b) to the Company.
2.2 Deliveries.
(a) On or prior to the Closing, the Company shall deliver, or cause to be delivered, to the Purchaser the
following:
(i) this
Agreement duly executed by the Company; and
(ii) a
copy of the instructions to VStock Transfer, LLC (the “Transfer Agent”) instructing the Transfer Agent to issue in
book-entry form the Shares being purchased hereunder, registered in the name of Purchaser.
(b) On or prior to the Closing, the Purchaser shall deliver, or cause to be delivered, to the Company the
following:
(i) a completed Accredited Investor Questionnaire (as defined below);
(ii) this Agreement duly executed by the Purchaser; and
(iii) the Purchaser’s subscription amount in the full amount of the Purchase Price for the Shares being
purchased by wire transfer funds.
2.3 Restrictive Legend.
The Shares have not been registered under the Securities Act of 1933, as amended (the “Securities Act”), and will bear
the restrictive legend set forth in Section 4.1(b) hereto.
SECTION 3: REPRESENTATIONS AND WARRANTIES OF
THE PURCHASER
3.1 Representations and
Warranties of Purchaser. The Purchaser hereby represents and warrants as of the date hereof and as of the Closing to the Company as
follows:
(a) Organization;
Authority. The Purchaser is an entity duly incorporated or formed, validly existing and in good standing under the laws of the jurisdiction
of its incorporation or formation with full right, corporate, partnership, limited liability company or similar power and authority to
enter into and to consummate the transactions contemplated by this Agreement and otherwise to carry out its obligations hereunder and
thereunder. The execution and delivery of this Agreement and performance by the Purchaser of the transactions contemplated by this Agreement
have been duly authorized by all necessary corporate, partnership, limited liability company, investment management or similar action,
as applicable, on the part of the Purchaser. This Agreement has been duly executed by the Purchaser, and when delivered by the Purchaser
in accordance with the terms hereof, will constitute the valid and legally binding obligation of the Purchaser, enforceable against it
in accordance with its terms, except: (i) as such enforceability may be limited by bankruptcy, insolvency, reorganization or similar
laws affecting creditors’ rights generally; (ii) as enforceability of any indemnification or contribution provision may be
limited under the federal or state securities laws; and (iii) that the remedy of specific performance and injunctive and other forms
of equitable relief may be subject to the equitable defenses and to the discretion of the court before which any proceeding therefor may
be brought.
(b) Investment
Purpose. The Purchaser is acquiring the Shares for its own account for investment only and not with a view towards, or for resale
in connection with, the public sale or distribution thereof. The Purchaser acknowledges that the Shares will be issued in book-entry form
with a notation of restriction, as set forth in Section 4.1(b).
(c) Experience
of the Purchaser. The Purchaser, either alone or together with its representatives, has such knowledge, sophistication and experience
in business and financial matters so as to be capable of evaluating the merits and risks of the prospective investment in the Shares,
and has so evaluated the merits and risks of such investment. The Purchaser is able to bear the economic risk of an investment in the
Shares, and, at the present time, is able to afford a complete loss of such investment.
(d) Accredited
Investor Status. The Purchaser is an “accredited investor” as that term is defined in Rule 501(a) of Regulation
D, as promulgated under the Securities Act and has delivered to the Company a completed Accredited Investor Questionnaire in the form
attached hereto as Exhibit A (the “Accredited Investor Questionnaire”).
(e) Reliance
on Exemptions; Restricted Securities. None of the Shares are registered under the Securities Act, or any state securities laws.
The Purchaser acknowledges that the Shares have not been recommended by any U.S. Federal or State securities commission or regulatory
authority and have not confirmed the accuracy or determined the adequacy of this Agreement. The Purchaser understands that the offering
and sale of the Shares is intended to be exempt from registration under the Securities Act, by virtue of Section 4(a)(2) thereof and/or
Rule 506(b) of Regulation D, as promulgated under the Securities Act, and, based in part upon the representations, warranties and agreements
of the Purchaser contained in this Agreement. The Purchaser understands that the Shares may not be sold, transferred or otherwise disposed
of without registration under the Securities Act or an exemption therefrom.
2
(f) Information.
All materials relating to the business, financial condition, management and operations of the Company and materials relating to the offer
and sale of the Shares which have been requested by the Purchaser have been furnished or otherwise made available to the Purchaser or
its advisors, including, without limitation, all reports and other documents filed with or furnished to the U.S. Securities and Exchange
Commission (the “Commission”) by the Company pursuant to the reporting requirements of the Securities Exchange Act
of 1934, as amended (the “Exchange Act”), including all materials filed with or furnished to the Commission pursuant
to Section 13(a), 13(c), 14 or 15(d) of the Exchange Act, since December 31, 2025, including, without limitation, the Annual Report on
Form 10-K filed by the Company for its fiscal year ended December 31, 2025. The Purchaser and its advisors, if any, have been afforded
the opportunity to ask questions of the Company and its management. The Purchaser understands that its investment in the Shares, involves
a high degree of risk. The Purchaser has sought such accounting, legal and tax advice as it has considered necessary to make an
informed investment decision with respect to its acquisition of the Shares.
(g) General
Solicitation. The Purchaser is not purchasing the Shares as a result of any advertisement, article, notice or other communication
regarding the Shares published in any newspaper, magazine or similar media or broadcast over television or radio or presented at any seminar
or any other general solicitation or general advertisement.
(h) No
Governmental Review. The Purchaser understands that no United States federal or state governmental authority has passed on or made
any recommendation or endorsement of the Shares, or the fairness or suitability of the investment in the Shares, nor have such governmental
authorities passed upon or endorsed the merits of the offering of the Shares.
(i) Certain
Transactions and Confidentiality. Other than consummating the transactions contemplated hereunder, the Purchaser has not, nor has
any person acting on behalf of or pursuant to any understanding with the Purchaser, directly or indirectly executed any purchases or sales,
including Short Sales (as defined in Rule 200 of Regulation SHO under the Exchange Act), of the securities of the Company during
the period commencing as of the time that the Purchaser first received a term sheet (written or oral) from the Company or any other person
representing the Company setting forth the material terms of the transactions contemplated hereunder and ending immediately prior to the
execution hereof. Other than to the Company or to the Purchaser’s representatives, including, without limitation, its officers,
directors, partners, legal and other advisors, employees, agents and affiliates, the Purchaser has maintained the confidentiality of all
disclosures made to it in connection with this transaction (including the existence and terms of this transaction).
SECTION 4: OTHER AGREEMENTS OF THE PARTIES
4.1 Transfer and Restrictive
Legend.
(a) The
Shares may only be disposed of in compliance with state and federal securities laws. In connection with any transfer of Shares other than
pursuant to an effective registration statement, the Company may require the transferor thereof to provide to the Company an opinion of
counsel selected by the transferor and reasonably acceptable to the Company, the form and substance of which opinion shall be reasonably
satisfactory to the Company, to the effect that such transfer does not require registration of such transferred Shares under the Securities
Act.
(b) The
Purchaser agrees to a restrictive notation on the Shares to be issued in book entry form as follows:
“THESE SECURITIES HAVE BEEN ACQUIRED FROM
THE ISSUER WITHOUT REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”) AND ARE RESTRICTED SECURITIES
AS THAT TERM IS DEFINED UNDER RULE 144, PROMULGATED UNDER THE SECURITIES ACT. THESE SECURITIES MAY NOT BE SOLD, PLEDGED, TRANSFERRED,
DISTRIBUTED, OR OTHERWISE DISPOSED OF IN ANY MANNER UNLESS SUCH TRANSACTION IS (I) REGISTERED UNDER THE SECURITIES ACT, (II) UNLESS
SOLD PURSUANT TO RULE 144 OR RULE 144A UNDER SAID ACT, OR (III) SOLD PURSUANT TO A VALID EXEMPTION FROM SUCH REGISTRATION REQUIREMENTS
AS EVIDENCED BY AN OPINION OF COUNSEL, REASONABLY SATISFACTORY TO THE ISSUER, STATING THAT THE TRANSFER DOES NOT INVOLVE A TRANSACTION
REQUIRING REGISTRATION OF SUCH SECURITIES UNDER THE SECURITIES ACT.”
3
4.2 Securities Laws Disclosure;
Publicity. No later than two (2) business days immediately following the date of this Agreement, the Company shall file a Current
Report on Form 8-K (the “Announcement 8-K”), including the Agreement as an exhibit thereto, with the U.S. Securities
and Exchange Commission.
4.3 Certain Transactions
and Confidentiality. The Purchaser covenants that neither it nor any of its affiliates acting on its behalf or pursuant to any understanding
with it will execute any purchases, sales or effect any other transactions, including Short Sales of any of the Company’s securities
during the period commencing with the execution of this Agreement and ending at such time that the transactions contemplated herein are
first publicly announced pursuant to the filing of the Announcement 8-K as described above. The Purchaser covenants that until such time
as the transactions contemplated herein are publicly disclosed by the Company pursuant to the filing of the Announcement 8-K, the Purchaser
will maintain the confidentiality of the existence and terms of this transaction and the information included in this Agreement.
4.4 Form D; Blue Sky
Filings. The Company agrees to timely file a Form D with respect to the Shares as required under Regulation D. The Company shall
take such action as the Company shall reasonably determine is necessary in order to obtain an exemption for, or to qualify the Shares
for, sale to the Purchaser at the Closing under applicable securities or “Blue Sky” laws of the states of the United States.
4.5 Stabilization.
Neither the Purchaser, the Company nor, to its knowledge, any of the Company’s employees, directors or shareholders, has taken or
shall take, directly or indirectly, any action designed to or that has constituted or that might reasonably be expected to cause or result
in, under Regulation M of the Exchange Act, or otherwise, stabilization or manipulation of the price of any security of the Company to
facilitate the sale or resale of the Shares.
SECTION 5: MISCELLANEOUS
5.1 Governing Law.
All questions concerning the construction, validity, enforcement and interpretation of this Agreement shall be governed by and construed
and enforced in accordance with the internal laws of the State of New York, without regard to the principles of conflicts of law thereof.
Each party agrees that all legal proceedings concerning the interpretations, enforcement and defense of the transactions contemplated
by this Agreement (whether brought against a party hereto or its respective affiliates, directors, officers, shareholders, partners, members,
employees or agents) shall be commenced exclusively in the state and federal courts sitting in the City of New York. Each party hereby
irrevocably submits to the exclusive jurisdiction of the state and federal courts sitting in the City of New York, Borough of Manhattan
for the adjudication of any dispute hereunder or in connection herewith or with any transaction contemplated hereby or discussed herein
(including with respect to the enforcement of this Agreement), and hereby irrevocably waives, and agrees not to assert in any action or
proceeding, any claim that it is not personally subject to the jurisdiction of any such court, that such action or proceeding is improper
or is an inconvenient venue for such proceeding. Each party hereby irrevocably waives personal service of process and consents to process
being served in any such action or proceeding by mailing a copy thereof via registered or certified mail or overnight delivery (with evidence
of delivery) to such party at the address in effect for notices to it under this Agreement and agrees that such service shall constitute
good and sufficient service of process and notice thereof. Nothing contained herein shall be deemed to limit in any way any right to serve
process in any other manner permitted by law. If any party shall commence an action or proceeding to enforce any provisions of this Agreement,
then the prevailing party in such action or proceeding shall be reimbursed by the non-prevailing party for its reasonable attorneys’
fees and other costs and expenses incurred with the investigation, preparation and prosecution of such action or proceeding.
4
5.2 Survival. The terms,
conditions and agreements made herein shall survive the Closing.
5.3 Successors and Assigns.
Except as otherwise expressly provided herein, the provisions hereof shall inure to the benefit of, and be binding upon, the successors,
assigns, heirs, executors and administrators of the parties hereto.
5.4 Entire Agreement; Amendment;
Waiver. This Agreement constitutes the entire and full understanding and agreement between the parties with regard to the subject
matter hereof. Neither this Agreement nor any term hereof may be amended, waived, discharged or terminated, except by a written instrument
signed by all the parties hereto.
5.5 Counterparts; Electronic
Signature. This Agreement may be executed in any number of counterparts, each of which shall be an original, but all of which together,
shall constitute one instrument. This Agreement may be executed by facsimile or pdf signature by any party and such signature will be
deemed binding for all purposes hereof without delivery of an original signature being thereafter required.
5.6 Fees and Expenses.
Each party shall bear its own fees and expenses in connection with the negotiation, execution and delivery of this Agreement.
[The remainder of this page has been intentionally
left blank.]
5
IN WITNESS WHEREOF, the undersigned have
hereunto set their hands as of the day and year first above written.
CLEARSIGN TECHNOLOGIES CORPORATION
By:
/s/ Colin James Deller
Name:
Colin James Deller
Title:
Chief Executive Officer
PURCHASER
Otter
Capital LLC
By:
/s/ John M. Pasquesi
Name:
John M. Pasquesi
Title:
Sole Member
6
EXHIBIT A
ACCREDITED INVESTOR QUESTIONNAIRE
(see attached)
7
EX-99.1 — EXHIBIT 99.1
EX-99.1
Filename: tm2621046d1_ex99-1.htm · Sequence: 4
Exhibit 99.1
ClearSign Announces Private Placement of $1,770,000
At the Market Transaction with Existing Stockholder
TULSA, Okla., July 23, 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 the completion of a private placement (the “Placement”) of 500,000 shares of its common stock, par value $0.001
per share, with an existing stockholder at a price of $3.54 per share, the average closing price reported on Nasdaq for the five trading
days ending on June 21, 2026, for gross proceeds of $1,770,000. The Placement closed on July 22, 2026.
ClearSign intends to use the net proceeds from the Placement for working
capital, research and development, marketing and sales, and general corporate purposes.
“We very much appreciate, and are encouraged by, the continued
the support of this long time stockholder,” said Jim Deller, Ph.D., Chief Executive Officer of ClearSign.
The securities offered in the Placement have not been registered under
the Securities Act of 1933, as amended, and may not be offered or sold in the United States absent registration or an applicable exemption
from the registration requirements. This press release shall not constitute an offer to sell or the solicitation of an offer to buy, nor
shall there be any sale of the securities in any jurisdiction in which such offer, solicitation, or sale would be unlawful.
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
Cautionary Note on Forward-Looking Statements
All statements in this press release relating to the Placement that
are not based on historical fact are “forward-looking statements.” 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 anticipated use of the net proceeds of the
Placement, and other factors identified in the Company’s Annual Report on Form 10-K and other periodic and current reports
filed with the U.S. Securities and Exchange Commission 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 becomes aware.
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Jul. 21, 2026
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