THE REGISTERED HOLDER
OF THIS PURCHASE WARRANT BY ITS ACCEPTANCE HEREOF, AGREES THAT IT WILL NOT SELL, TRANSFER OR ASSIGN THIS PURCHASE WARRANT EXCEPT
AS HEREIN PROVIDED AND THE REGISTERED HOLDER OF THIS PURCHASE WARRANT AGREES THAT IT WILL NOT SELL, TRANSFER, ASSIGN, PLEDGE OR
HYPOTHECATE THIS PURCHASE WARRANT FOR A PERIOD OF ONE HUNDRED EIGHTY DAYS FOLLOWING THE COMMENCEMENT DATE (DEFINED BELOW) TO ANYONE
OTHER THAN (I) BREAN CAPITAL, LLC, OR (II) A BONA FIDE OFFICER OR PARTNER OF BREAN CAPITAL, LLC.


 


THIS PURCHASE WARRANT
IS NOT EXERCISABLE PRIOR TO SEMPTEMBER 5, 2014. VOID AFTER 5:00 P.M., EASTERN TIME, MARCH 5, 2019.


 


COMMON STOCK PURCHASE WARRANT #D-1


 


For the Purchase of 20,313 Shares of Common
Stock


 


of


 


CLEARSIGN
COMBUSTION CORPORATION


 


1.          Purchase
Warrant. THIS CERTIFIES THAT, in consideration of funds duly paid by or on behalf of Brean Capital, LLC (“Holder”),
as registered owner of this Purchase Warrant, to ClearSign Combustion Corporation, a Washington corporation (the “Company”),
Holder is entitled, at any time or from time to time from March 5, 2014 (the “Commencement Date”), and at or
before 5:00 p.m., Eastern time, March 5, 2019 (the ”Expiration Date”), but not thereafter, to subscribe
for, purchase and receive, in whole or in part, up to 20,313 shares of common stock of the Company, par value $0.0001 per share
(the “Shares”), subject to adjustment as provided in Section 6 hereof. If the Expiration Date is a day on which
banking institutions are authorized by law to close, then this Purchase Warrant may be exercised on the next succeeding day which
is not such a day in accordance with the terms herein. During the period ending on the Expiration Date, the Company agrees not
to take any action that would terminate the Purchase Warrant. This Purchase Warrant is initially exercisable at $10.00 per Share
(125% of the price of the Shares sold in the Offering); provided, however, that upon the occurrence of any of the
events specified in Section 6 hereof, the rights granted by this Purchase Warrant, including the exercise price per Share and the
number of Shares to be received upon such exercise, shall be adjusted as therein specified. The term “Exercise Price”
shall mean the initial exercise price or the adjusted exercise price, depending on the context.


 




    	 



    	 



    

 


2.           Exercise.


 


2.1           Exercise
Form. In order to exercise this Purchase Warrant, the exercise form attached hereto must be duly executed and completed and
delivered to the Company, together with this Purchase Warrant and payment of the Exercise Price for the Shares being purchased
payable in cash by wire transfer of immediately available funds to an account designated by the Company or by certified check or
official bank check. If the subscription rights represented hereby shall not be exercised at or before 5:00 p.m., Eastern time,
on the Expiration Date, this Purchase Warrant shall become and be void without further force or effect, and all rights represented
hereby shall cease and expire.


 


2.2           Cashless
Exercise.  If at any time after the Commencement Date there is no effective registration statement registering, or no
current prospectus available for, the resale of the Shares by the Holder, then in lieu of exercising this Purchase Warrant by payment
of cash or check payable to the order of the Company pursuant to Section 2.1 above, Holder may elect to receive the number of Shares
equal to the value of this Purchase Warrant (or the portion thereof being exercised), by surrender of this Purchase Warrant to
the Company, together with the exercise form attached hereto, in which event the Company shall issue to Holder, Shares in accordance
with the following formula:


 


	X	=	Y(A-B)	 
	A	 


 


	Where,	X	=	The number of Shares to be issued to Holder;
	 	Y	=	The number of Shares for which the Purchase Warrant is being exercised;
	 	A	=	The fair market value of one Share; and
	 	B	=	The Exercise Price.


 


For purposes of this
Section 2.2, the fair market value of a Share is defined as follows:


 


		(i)	if the Company’s common stock is traded on a securities exchange, the value shall be deemed
to be the closing price on such exchange prior to the exercise form being submitted in connection with the exercise of the Purchase
Warrant; or



 


		(ii)	if the Company’s common stock is actively traded over-the-counter, the value shall be deemed
to be the closing bid prior to the exercise form being submitted in connection with the exercise of the Purchase Warrant; if there
is no active public market, the value shall be the fair market value thereof, as determined in good faith by the Company’s
Board of Directors.



 


2.3           Legend.
Each certificate for the securities purchased under this Purchase Warrant shall bear a legend as follows unless such securities
have been registered under the Securities Act of 1933, as amended (the “Securities Act”):


 




    	 



    	 



    

 


“The securities
represented by this certificate have not been registered under the Securities Act of 1933, as amended (the “Securities
Act”), or applicable state law. Neither the securities nor any interest therein may be offered for sale, sold or otherwise
transferred except pursuant to an effective registration statement under the Securities Act, or pursuant to an exemption
from registration under the Securities Act and applicable state law which, in the opinion of counsel to the Company, is
available.”


 


3.           Transfer.


 


3.1           General
Restrictions. The registered Holder of this Purchase Warrant agrees by his, her or its acceptance hereof, that such Holder
will not: (a) sell, transfer, assign, pledge or hypothecate this Purchase Warrant for a period of one hundred eighty (180) days
following the Effective Date to anyone other than: (i) Brean Capital, LLC (“Brean”) or a placement agent or
a selected dealer participating in the Offering, or (ii) a bona fide officer or partner of Brean or of any such placement agent
or selected dealer, in each case in accordance with FINRA Conduct Rule 5110(g)(1), or (b) cause this Purchase Warrant or the securities
issuable hereunder to be the subject of any hedging, short sale, derivative, put or call transaction that would result in the effective
economic disposition of this Purchase Warrant or the securities hereunder, except as provided for in FINRA Rule 5110(g)(2). On
and after 180 days after the Effective Date, transfers to others may be made subject to compliance with or exemptions from applicable
securities laws. In order to make any permitted assignment, the Holder must deliver to the Company the assignment form attached
hereto duly executed and completed, together with the Purchase Warrant and payment of all transfer taxes, if any, payable in connection
therewith. The Company shall within five (5) business days transfer this Purchase Warrant on the books of the Company and shall
execute and deliver a new Purchase Warrant or Purchase Warrants of like tenor to the appropriate assignee(s) expressly evidencing
the right to purchase the aggregate number of Shares purchasable hereunder or such portion of such number as shall be contemplated
by any such assignment.


 


3.2           Restrictions
Imposed by the Securities Act. The securities evidenced by this Purchase Warrant shall not be transferred unless and until:
(i) the Company has received an opinion of Company counsel that the securities may be transferred pursuant to an exemption from
registration under the Securities Act and applicable state securities laws, the availability of which is established to
the reasonable satisfaction of the Company, or (ii) a registration statement or a post-effective amendment to the Registration
Statement relating to the offer and sale of such securities has been filed by the Company and declared effective by the U.S. Securities
and Exchange Commission (the “Commission”) and compliance with applicable state securities law has been
established.


 






    	 



    	 



    

 


4.           Registration
Rights.


 


4.1          Demand
Registration.


 





4.1.1           Grant
of Right. The Company, upon written demand (a “Demand Notice”) of the Holder(s) of at least 51% of the Purchase
Warrants and/or the underlying Shares (“Majority Holders”), agrees to register, on one occasion, all or any
portion of the Shares underlying the Purchase Warrants (collectively, the “Registrable Securities”). On such
occasion, the Company will file a registration statement with the Commission covering the Registrable Securities within sixty (60)
days after receipt of a Demand Notice and use its reasonable best efforts to have the registration statement declared effective
promptly thereafter, subject to compliance with review by the Commission; provided, however, that the Company shall
not be required to comply with a Demand Notice if the Company has filed a registration statement with respect to which the Holder
is entitled to piggyback registration rights pursuant to Section 4.2 hereof and either: (i) the Holder has elected to participate
in the offering covered by such registration statement or (ii) if such registration statement relates to an underwritten primary
offering of securities of the Company, until the offering covered by such registration statement has been withdrawn or until thirty
(30) days after such offering is consummated. The demand for registration may be made at any time during a period of four (4) years
beginning one (1) year after the Effective Date. The Company covenants and agrees to give written notice of its receipt of any
Demand Notice by any Holder(s) to all other registered Holders of the Purchase Warrants and/or the Registrable Securities within
ten (10) days after the date of the receipt of any such Demand Notice.


 


4.1.2           Terms.
The Company shall bear all fees and expenses attendant to the registration of the Registrable Securities pursuant to Section 4.1.1,
but the Holders shall pay any and all underwriting commissions and the expenses of any legal counsel selected by the Holders to
represent them in connection with the sale of the Registrable Securities. The Company agrees to use its reasonable best efforts
to cause the filing required herein to become effective promptly and to qualify or register the Registrable Securities in such
states as are reasonably requested by the Holder(s); provided, however, that in no event shall the Company be required
to register the Registrable Securities in a State in which such registration would cause: (i) the Company to be obligated to register
or license to do business in such State or submit to general service of process in such State, or (ii) the principal shareholders
of the Company to be obligated to escrow their shares of capital stock of the Company. The Company shall cause any registration
statement filed pursuant to the demand right granted under Section 4.1.1 to remain effective for a period of at least twelve (12)
consecutive months after the date that the Holders of the Registrable Securities covered by such registration statement are first
given the opportunity to sell all of such securities. The Holders shall only use the prospectuses provided by the Company to sell
the shares covered by such registration statement, and will immediately cease to use any prospectus furnished by the Company if
the Company advises the Holder that such prospectus may no longer be used due to a material misstatement or omission. Notwithstanding
the provisions of this Section 4.1.2, the Holder shall be entitled to a demand registration under this Section 4.1.2 on only one
(1) occasion and such demand registration right shall terminate on the fifth anniversary of the Commencement Date.


 


4.2          “Piggy-Back”
Registration.


 


4.2.1           Grant
of Right. In addition to the demand right of registration described in Section 4.1 hereof, the Holder shall have the right,
until such right terminates on the fourth anniversary of the Commencement Date, to include the Registrable Securities as part of
any other registration of securities filed by the Company (other than in connection with a transaction contemplated by Rule 145
(a) promulgated under the Securities Act or pursuant to Form S-8, Form S-4 or any equivalent forms); provided, however,
that if, solely in connection with any primary underwritten public offering for the account of the Company, the managing underwriter(s)
thereof shall, in its reasonable discretion, exclude entirely or impose a limitation on the number of shares of Common Stock which
may be included in the Registration Statement because, in such underwriter(s)’ judgment, marketing or other factors dictate
such limitation is necessary to facilitate public distribution, then the Company shall be able to exclude entirely or be obligated
only to include in such Registration Statement only such limited portion of the Registrable Securities with respect to which the
Holder requested inclusion hereunder as the underwriter shall reasonably permit. Any exclusion of Registrable Securities shall
be made pro rata among the Holders seeking to include Registrable Securities in proportion to the number of Registrable Securities
sought to be included by such Holders; provided, however, that the Company shall not exclude any Registrable Securities
unless the Company has first excluded all outstanding securities, the holders of which are not entitled to inclusion of such securities
in such Registration Statement or are not entitled to pro rata inclusion with the Registrable Securities.


 




    	 



    	 



    

 


4.2.2           Terms.
The Company shall bear all fees and expenses attendant to registering the Registrable Securities pursuant to Section 4.2.1 hereof,
but the Holders shall pay any and all underwriting commissions and the expenses of any legal counsel selected by the Holders to
represent them in connection with the sale of the Registrable Securities. In the event of such a proposed registration, the Company
shall furnish the then Holders of outstanding Registrable Securities with not less than twenty (20) days written notice prior to
the proposed date of filing of such registration statement. Such notice to the Holders shall continue to be given for each registration
statement filed by the Company until such time as all of the Registrable Securities have been sold by the Holder. The holders of
the Registrable Securities shall exercise the “piggy-back” rights provided for herein by giving written notice within
ten (10) days of the receipt of the Company’s notice of its intention to file a registration statement. Except as otherwise
provided in this Purchase Warrant, there shall be no limit on the number of times the Holder may request registration under this
Section 4.2.2; provided, however, that such registration rights shall terminate on the fourth anniversary of the
Commencement Date.


 


4.3          General
Terms.


 


4.3.1           Indemnification.
The Company shall indemnify the Holder(s) of the Registrable Securities to be sold pursuant to any registration statement hereunder
and each person, if any, who controls such Holders within the meaning of Section 15 of the Securities Act or Section 20
(a) of the Securities Exchange Act of 1934, as amended (“Exchange Act”), against all loss, claim, damage, expense
or liability (including all reasonable attorneys’ fees and other expenses reasonably incurred in investigating, preparing
or defending against any claim whatsoever) to which any of them may become subject under the Securities Act, the Exchange
Act or otherwise, arising from such registration statement but only to the same extent and with the same effect as the provisions
pursuant to which the Company has agreed to indemnify the Placement Agent contained in Section 8(a) of the Placement Agency Agreement
between the Placement Agent and the Company, dated as of February 27, 2014. The Holder(s) of the Registrable Securities to be sold
pursuant to such registration statement, and their successors and assigns, shall severally, and not jointly, indemnify the Company,
against all loss, claim, damage, expense or liability (including all reasonable attorneys’ fees and other expenses reasonably
incurred in investigating, preparing or defending against any claim whatsoever) to which they may become subject under the Securities
Act, the Exchange Act or otherwise, arising from information furnished by or on behalf of such Holders, or their successors
or assigns, in writing, for specific inclusion in such registration statement to the same extent and with the same effect as the
provisions contained in Section 8(b) of the Placement Agency Agreement pursuant to which the Placement Agent has agreed to indemnify
the Company.


 


4.3.2           Exercise
of Purchase Warrants. Nothing contained in this Purchase Warrant shall be construed as requiring the Holder(s) to exercise
their Purchase Warrants prior to or after the initial filing of any registration statement or the effectiveness thereof.


 




    	 



    	 



    

 


4.3.3           Documents
to be Delivered by Holder(s). Each of the Holder(s) participating in any of the foregoing offerings shall furnish to the Company
a completed and executed questionnaire provided by the Company requesting information customarily sought of selling security holders.


 


5.           New
Purchase Warrants to be Issued.


 


5.1           Partial
Exercise or Transfer. Subject to the restrictions in Section 3 hereof, this Purchase Warrant may be exercised or assigned in
whole or in part. In the event of the exercise or assignment hereof in part only, upon surrender of this Purchase Warrant for cancellation,
together with the duly executed exercise or assignment form and funds sufficient to pay any Exercise Price and/or transfer tax
if exercised pursuant to Section 2.1 hereto, the Company shall cause to be delivered to the Holder without charge a new Purchase
Warrant of like tenor to this Purchase Warrant in the name of the Holder evidencing the right of the Holder to purchase the number
of Shares purchasable hereunder as to which this Purchase Warrant has not been exercised or assigned.


 


5.2           Lost
Certificate. Upon receipt by the Company of evidence satisfactory to it of the loss, theft, destruction or mutilation of this
Purchase Warrant and of reasonably satisfactory indemnification or the posting of a bond, the Company shall execute and deliver
a new Purchase Warrant of like tenor and date. Any such new Purchase Warrant executed and delivered as a result of such loss, theft,
mutilation or destruction shall constitute a substitute contractual obligation on the part of the Company.


 


6.           Adjustments.


 


6.1           Adjustments
to Exercise Price and Number of Securities. The Exercise Price and the number of Shares underlying the Purchase Warrant shall
be subject to adjustment from time to time as hereinafter set forth:


 


6.1.1           Share
Dividends; Splits. If, after the date hereof, and subject to the provisions of Section 6.3 below, the number of outstanding
Shares is increased by a stock dividend payable in Shares or by a split up of Shares or other similar event, then, on the effective
day thereof, the number of Shares purchasable hereunder shall be increased in proportion to such increase in outstanding Shares,
and the Exercise Price shall be proportionately decreased.


 


6.1.2           Aggregation
of Shares. If, after the date hereof, and subject to the provisions of Section 6.3 below, the number of outstanding Shares
is decreased by a consolidation, combination or reclassification of Shares or other similar event, then, on the effective date
thereof, the number of Shares purchasable hereunder shall be decreased in proportion to such decrease in outstanding Shares, and
the Exercise Price shall be proportionately increased.


 




    	 



    	 



    

 


6.1.3           Replacement
of Securities upon Reorganization, etc. In case of any reclassification or reorganization of the outstanding Shares other than
a change covered by Section 6.1.1 or 6.1.2 hereof or that solely affects the par value of such Shares, or in the case of any share
reconstruction or amalgamation or consolidation of the Company with or into another corporation (other than a consolidation or
share reconstruction or amalgamation in which the Company is the continuing corporation and that does not result in any reclassification
or reorganization of the outstanding Shares), or in the case of any sale or conveyance to another corporation or entity of the
property of the Company as an entirety or substantially as an entirety in connection with which the Company is dissolved, the Holder
of this Purchase Warrant shall have the right thereafter (until the expiration of the right of exercise of this Purchase Warrant)
to receive upon the exercise hereof, for the same aggregate Exercise Price payable hereunder immediately prior to such event, the
kind and amount of shares of stock or other securities or property (including cash) receivable upon such reclassification, reorganization,
share reconstruction or amalgamation, or consolidation, or upon a dissolution following any such sale or transfer, by a Holder
of the number of Shares of the Company obtainable upon exercise of this Purchase Warrant immediately prior to such event; and if
any reclassification also results in a change in Shares covered by Section 6.1.1 or 6.1.2, then such adjustment shall be made pursuant
to Sections 6.1.1, 6.1.2 and this Section 6.1.3. The provisions of this Section 6.1.3 shall similarly apply to successive reclassifications,
reorganizations, share reconstructions or amalgamations, or consolidations, sales or other transfers.


 


6.1.4           Changes
in Form of Purchase Warrant. This form of Purchase Warrant need not be changed because of any change pursuant to this Section
6.1, and Purchase Warrants issued after such change may state the same Exercise Price and the same number of Shares as are stated
in the Purchase Warrants initially issued pursuant to this Agreement. The acceptance by any Holder of the issuance of new Purchase
Warrants reflecting a required or permissive change shall not be deemed to waive any rights to an adjustment occurring after the
Commencement Date or the computation thereof.


 


6.2          Reserved.


 


6.3          Elimination
of Fractional Interests. The Company shall not be required to issue certificates representing fractions of Shares upon the
exercise of the Purchase Warrant, nor shall it be required to issue scrip or pay cash in lieu of any fractional interests, it being
the intent of the parties that all fractional interests shall be eliminated by rounding any fraction up or down, as the case may
be, to the nearest whole number of Shares or other securities, properties or rights.


 


7.           Reservation
and Listing. The Company shall at all times reserve and keep available out of its authorized Shares, solely for the purpose
of issuance upon exercise of the Purchase Warrants, such number of Shares or other securities, properties or rights as shall be
issuable upon the exercise thereof. The Company covenants and agrees that, upon exercise of the Purchase Warrants and payment of
the Exercise Price therefor, in accordance with the terms hereby, all Shares and other securities issuable upon such exercise shall
be duly and validly issued, fully paid and non-assessable and not subject to preemptive rights of any shareholder. The Company
further covenants and agrees that upon exercise of the Purchase Warrants and payment of the exercise price therefor, all Shares
and other securities issuable upon such exercise shall be duly and validly issued, fully paid and non-assessable and not subject
to preemptive rights of any shareholder. As long as the Purchase Warrants shall be outstanding, the Company shall use its commercially
reasonable efforts to cause all Shares issuable upon exercise of the Purchase Warrants to be listed (subject to official notice
of issuance) on all national securities exchanges (or, if applicable, on the OTC Bulletin Board or any successor trading market)
on which the Shares issued to the public in the Offering may then be listed and/or quoted.


 




    	 



    	 



    

 


8.           Certain
Notice Requirements.


 


8.1           Holder’s
Right to Receive Notice. Nothing herein shall be construed as conferring upon the Holders the right to vote or consent or to
receive notice as a shareholder for the election of directors or any other matter, or as having any rights whatsoever as a shareholder
of the Company. If, however, at any time prior to the expiration of the Purchase Warrants and their exercise, any of the events
described in Section 8.2 shall occur, then, in one or more of said events, the Company shall give written notice of such event
at least ten days prior to the date fixed as a record date or the effective date the transfer books for the determination of the
shareholders entitled to such dividend, distribution, conversion or exchange of securities or subscription rights, or entitled
to vote on such proposed dissolution, liquidation, winding up or sale. Such notice shall specify such record date or the date of
the closing of the transfer books, as the case may be. Notwithstanding the foregoing, the Company shall deliver to each Holder
a copy of each notice given to the other shareholders of the Company at the same time and in the same manner that such notice is
given to the shareholders.


 


8.2           Events
Requiring Notice. The Company shall be required to give the notice described in this Section 8 upon one or more of the following
events: (i) if the Company shall take a record of the holders of its Shares for the purpose of entitling them to receive a dividend
or distribution payable otherwise than in cash, or a cash dividend or distribution payable otherwise than out of retained earnings,
as indicated by the accounting treatment of such dividend or distribution on the books of the Company, (ii) the Company shall offer
to all the holders of its Shares any additional shares of capital stock of the Company or securities convertible into or exchangeable
for shares of capital stock of the Company, or any option, right or warrant to subscribe therefor, or (iii) a dissolution, liquidation
or winding up of the Company (other than in connection with a consolidation or share reconstruction or amalgamation) or a sale
of all or substantially all of its property, assets and business shall be proposed.


 


8.3           Notice
of Change in Exercise Price. The Company shall, promptly after an event requiring a change in the Exercise Price pursuant to
Section 6 hereof, send notice to the Holders of such event and change (“Price Notice”). The Price Notice shall
describe the event causing the change and the method of calculating same and shall be certified as being true and accurate by the
Company’s Chief Financial Officer.


 


8.4           Transmittal
of Notices. All notices, requests, consents and other communications under this Purchase Warrant shall be in writing and shall
be deemed to have been duly made when hand delivered, or mailed by express mail or private courier service: (i) if to the registered
Holder of the Purchase Warrant, to the following address of the Holder or to such other address as the Holder may designate by
notice to the Company, or (ii) if to the Company, to following address or to such other address as the Company may designate by
notice to the Holders:


 




    	 



    	 



    

 


If to the Holder:


 


Brean Capital, LLC

1345 Avenue of the Americas, 29th Floor

New York, New York 10105

Attn: Mr. William McCluskey, Senior Managing Director


Fax No.: (212) 702-6548


 


with a copy (which shall not constitute notice) to:




Sichenzia Ross Friedman Ference LLP


61 Broadway, 32nd Floor


New York, NY 10006


Attention: Jay Kapowitz, Esq.


Fax No: (212) 935-9725


 


If to the Company:


 


ClearSign Combustion Corp.


12870 Interurban Avenue South


Seattle, Washington 98168


Attention: James N. Harmon, Chief Financial Officer


Fax No: (206) 299-3553


 


with a copy (which shall not constitute notice) to:


 


Richardson & Patel, LLP


The Chrysler Building,


405 Lexington Avenue, 49th Floor


New York, NY 10174


Attention: Kevin Friedmann, Esq.


Fax No: (917) 591-6898


 


9.           Miscellaneous.


 


9.1           Amendments.
The Company and Brean may from time to time supplement or amend this Purchase Warrant without the approval of any of the Holders
in order to cure any ambiguity, to correct or supplement any provision contained herein that may be defective or inconsistent with
any other provisions herein, or to make any other provisions in regard to matters or questions arising hereunder that the Company
and Brean may deem necessary or desirable and that the Company and Brean deem shall not adversely affect the interest of the Holders.
All other modifications or amendments shall require the written consent of and be signed by the party against whom enforcement
of the modification or amendment is sought.


 


9.2           Headings.
The headings contained herein are for the sole purpose of convenience of reference, and shall not in any way limit or affect the
meaning or interpretation of any of the terms or provisions of this Purchase Warrant.


 




    	 



    	 



    

 


9.3.          Entire
Agreement. This Purchase Warrant (together with the other agreements and documents being delivered pursuant to or in connection
with this Purchase Warrant) constitutes the entire agreement of the parties hereto with respect to the subject matter hereof, and
supersedes all prior agreements and understandings of the parties, oral and written, with respect to the subject matter hereof.


 


9.4           Binding
Effect. This Purchase Warrant shall inure solely to the benefit of and shall be binding upon, the Holder and the Company and
their permitted assignees, respective successors, legal representative and assigns, and no other person shall have or be construed
to have any legal or equitable right, remedy or claim under or in respect of or by virtue of this Purchase Warrant or any provisions
herein contained.


 


9.5           Governing
Law; Submission to Jurisdiction; Trial by Jury. This Purchase Warrant shall be governed by and construed and enforced in accordance
with the laws of the State of New York, without giving effect to conflict of laws principles thereof. The Company hereby agrees
that any action, proceeding or claim against it arising out of, or relating in any way to this Purchase Warrant shall be brought
and enforced in the New York Supreme Court, County of New York, or in the United States District Court for the Southern District
of New York, and irrevocably submits to such jurisdiction, which jurisdiction shall be exclusive. The Company hereby waives any
objection to such exclusive jurisdiction and that such courts represent an inconvenient forum. Any process or summons to be served
upon the Company may be served by transmitting a copy thereof by registered or certified mail, return receipt requested, postage
prepaid, addressed to it at the address set forth in Section 8 hereof. Such mailing shall be deemed personal service and shall
be legal and binding upon the Company in any action, proceeding or claim. The Company and the Holder agree that the prevailing
party(ies) in any such action shall be entitled to recover from the other party(ies) all of its reasonable attorneys’ fees
and expenses relating to such action or proceeding and/or incurred in connection with the preparation therefor. The Company (on
its behalf and, to the extent permitted by applicable law, on behalf of its stockholders and affiliates) and the Holder hereby
irrevocably waive, to the fullest extent permitted by applicable law, any and all right to trial by jury in any legal proceeding
arising out of or relating to this Agreement or the transactions contemplated hereby.


 


9.6           Waiver,
etc. The failure of the Company or the Holder to at any time enforce any of the provisions of this Purchase Warrant shall not
be deemed or construed to be a waiver of any such provision, nor to in any way affect the validity of this Purchase Warrant or
any provision hereof or the right of the Company or any Holder to thereafter enforce each and every provision of this Purchase
Warrant. No waiver of any breach, non-compliance or non-fulfillment of any of the provisions of this Purchase Warrant shall be
effective unless set forth in a written instrument executed by the party or parties against whom or which enforcement of such waiver
is sought; and no waiver of any such breach, non-compliance or non-fulfillment shall be construed or deemed to be a waiver of any
other or subsequent breach, non-compliance or non-fulfillment.


 


9.7           Execution
in Counterparts. This Purchase Warrant may be executed in one or more counterparts, and by the different parties hereto in
separate counterparts, each of which shall be deemed to be an original, but all of which taken together shall constitute one and
the same agreement, and shall become effective when one or more counterparts has been signed by each of the parties hereto and
delivered to each of the other parties hereto. Such counterparts may be delivered by facsimile transmission or other electronic
transmission.


 




    	 



    	 



    

 


9.8           Exchange
Agreement. As a condition of the Holder’s receipt and acceptance of this Purchase Warrant, Holder agrees that, at any
time prior to the complete exercise of this Purchase Warrant by Holder, if the Company and Brean enter into an agreement (“Exchange
Agreement”) pursuant to which they agree that all outstanding Purchase Warrants will be exchanged for securities or cash
or a combination of both, then Holder shall agree to such exchange and become a party to the Exchange Agreement.


 


[Signature Page Follows]


 




    	 



    	 



    

 


IN WITNESS WHEREOF, the Company has caused
this Purchase Warrant to be signed by its duly authorized officer as of the 5th day of March, 2014.


 


	CLEARSIGN COMBUSTION CORPORATION	 
	 	 	 
	By:	/s/ James N. Harmon	 
	 	Name: James N. Harmon	 
	 	Title:  Chief Financial Officer	 


 




    	 



    	 



    

 


[Form to be used to exercise Purchase
Warrant]


 


Date: __________, 20___


 


The undersigned
hereby elects irrevocably to exercise the Purchase Warrant for ______ shares of common stock, par value $0.0001 per share (the
“Shares”), of ClearSign Combustion Corporation, a Washington corporation (the “Company”),
and hereby makes payment of $____ (at the rate of $____ per Share) in payment of the Exercise Price pursuant thereto. Please issue
the Shares as to which this Purchase Warrant is exercised in accordance with the instructions given below and, if applicable, a
new Purchase Warrant representing the number of Shares for which this Purchase Warrant has not been exercised.


 


or


 


The undersigned
hereby elects irrevocably to convert its right to purchase ___ Shares of the Company under the Purchase Warrant for ______ Shares,
as determined in accordance with the following formula:


 


	 	X	=	Y(A-B)	 
	 	 	 	A	 


 


	Where,	X	=	The number of Shares to be issued to Holder;
	 	Y	=	The number of Shares for which the Purchase Warrant is being exercised;
	 	A	=	The fair market value of one Share which is equal to $_____; and
	 	 	 	 
	 	B	=	


 


The Exercise Price
which is equal to $______ per share


 


The undersigned
agrees and acknowledges that the calculation set forth above is subject to confirmation by the Company and any disagreement with
respect to the calculation shall be resolved by the Company in its sole discretion.


 


Please issue
the Shares as to which this Purchase Warrant is exercised in accordance with the instructions given below and, if applicable, a
new Purchase Warrant representing the number of Shares for which this Purchase Warrant has not been converted.


 


	Signature	 	 


 


	Signature Guaranteed  	 	 


 




    	 



    	 



    

 


INSTRUCTIONS FOR REGISTRATION OF SECURITIES


 


	Name:	 	 
	 	(Print in Block Letters)	 
	 	 	 
	Address:	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	 


 


NOTICE: The signature
to this form must correspond with the name as written upon the face of the Purchase Warrant without alteration or enlargement or
any change whatsoever, and must be guaranteed by a bank, other than a savings bank, or by a trust company or by a firm having membership
on a registered national securities exchange.


 




    	 



    	 



    

 


[Form to be used to assign Purchase Warrant]


 


ASSIGNMENT


 


(To be executed by the registered Holder
to effect a transfer of the within Purchase Warrant):


 


FOR VALUE RECEIVED, __________________
does hereby sell, assign and transfer unto the right to purchase shares of common stock, par value $0.0001 per share, of ClearSign
Combustion Corporation, a Washington corporation (the “Company”), evidenced by the Purchase Warrant and does
hereby authorize the Company to transfer such right on the books of the Company.


 


Dated: __________, 20__


 


	Signature	 	 


 


	Signature Guaranteed  	 	 


 


NOTICE: The signature to this form must correspond with the
name as written upon the face of the within Purchase Warrant without alteration or enlargement or any change whatsoever, and must
be guaranteed by a bank, other than a savings bank, or by a trust company or by a firm having membership on a registered national
securities exchange.