Exhibit 10.9


 


 





SECOND AMENDMENT TO LEASE


 


 


THIS
SECOND AMENDMENT TO LEASE, dated as of the 29th day of September 2016, is entered into by and between RREEF AMERICA REIT II CORP.
MMMM7 WASHINGTON, a Maryland corporation (“Landlord”), and CLEARSIGN COMBUSTION CORPORATION, a Washington corporation
(“Tenant”).


 


RECITALS


 


A.     Landlord
and Tenant entered into that certain Lease dated August 19, 2011, as amended by that certain Commencement Date Memorandum dated
November 1, 2011, and by that certain First Amendment to Lease dated December 17, 2013 (collectively, the “Lease”).


 


B.      The
Lease pertains to approximately 9,200 square feet of space located in Building 1 of Gateway Corporate Center, having an address
of 12870 Interurban Avenue South, Seattle, King County, Washington (the “Existing Premises”), as more fully described
in the Lease.


 


C.      Landlord
and Tenant desire to extend the Term of the Lease, change the Rent Schedule, and otherwise amend the Lease as more fully set forth
below.


 


AMENDMENT


 


NOW,
THEREFORE, in consideration of the mutual covenants and conditions contained herein and other good and valuable consideration,
the receipt and sufficiency of which is hereby acknowledged, the parties agree as follows:


 


		1.	Definitions. Unless otherwise specifically set
forth herein, all capitalized terms used shall have the meanings attributed to them in the Lease.



 


		2.	Address for Rent Payment. The Address for Rent
Payment, as set forth on the Reference Pages of the Lease, is hereby amended to the following:



 


RREEF America REIT II Corp. MMMM7 Washington


pcl18001 - Gateway Corp Ctr - Bldg 1


PO Box 209273


Austin, Texas 78720-9273


 


		3.	Term. The Term of this Lease is hereby extended
for a period of three (3) years and one (1) month, commencing on March 1, 2017 and terminating on March 31, 2020.



 


		4.	Rent Schedule. The Rent Schedule for the period
from March 1, 2017 through March 31, 2020 shall be as follows:



 


	Period	
        Rentable Square

        Footage
	
        Annual Rent

        Per Square Foot
	Annual Rent	
        Monthly Installment

        of Rent

	from	through
	3/1/2017	3/31/2020	9,200	$16.00	$147,216.00	$12,268.00



 






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		5.	Landlord’s Work. Landlord, at its sole cost
and expense, shall replace the HVAC unit numbers 11, 12, 13 and 15 serving the Premises, at a time that is mutually agreeable
to Landlord and Tenant, prior to September 2017.



 


		6.	Effect of Amendment; Incorporation.Except
as expressly modified herein, all terms and conditions of the Lease remain in full force and effect and are hereby ratified and
confirmed.



 


 


IN
WITNESS WHEREOF, Landlord and Tenant have executed this Second Amendment to Lease as of the day and year first written above.


 





	LANDLORD: 	 	TENANT:
	 	 	 
	RREEF AMERICA REIT II CORP. MMMM7 	 	CLEARSIGN COMBUSTION
	WASHINGTON, a Maryland corporation 	 	CORPORATION, a Washington corporation
	 	 	 	 
	 	 	 	 
	By:	 	 	By:	    
	 	Cathleen Meyer, Vice President	 	Its:	    
	 	 	 	 	 
	Date:	 	 	Date:	               







 





 


 


CORPORATE ACKNOWLEDGMENT


 





	STATE OF WASHINGTON	)
		) ss.
	COUNTY OF KING	)







 





On
this ____ day of ________, 2016, before me, the undersigned, a Notary Public in and for the State of Washington, personally
appeared CATHLEEN MEYER, to me known or shown through satisfactory evidence to be the Vice President of RREEF AMERICA REIT II
CORP. MMMM7 WASHINGTON, a Maryland corporation, and acknowledged to me that she executed the same on behalf of said
corporation freely and voluntarily for the uses and purposes therein mentioned.


 


Witness
my hand and official seal the day and year in this certificate first above written.


 





	 	[SEAL]		 
	 	 	(Signature)	 
	 	 	
         

        
	 
	 	 	(Please print name legibly)	 
	 	 	 	 
	 	 	NOTARY PUBLIC in and for the State of Washington 	 
	 	 	Residing at  ______________________________	 
	 	 	My commission expires _____________________	 







  



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CORPORATE ACKNOWLEDGMENT


 





	STATE OF WASHINGTON	)
		) ss.
	COUNTY OF KING	)


 





On
this ____ day of _______ , 2016, before me, the undersigned, a Notary Public in and for the State of Washington,
personally appeared _________________, to me known or shown through satisfactory evidence to be the _______________
of CLEARSIGN COMBUSTION CORPORATION, a Washington corporation, and acknowledged to me that ________ executed the foregoing
instrument on behalf of said corporation freely and voluntarily for the uses and purposes therein mentioned.


 


Witness
my hand and official seal the day and year in this certificate first above written.


 


 





	 	[SEAL]		 
	 	 	(Signature)	 
	 	 	
         

        
	 
	 	 	(Please print name legibly)	 
	 	 	 	 
	 	 	NOTARY PUBLIC in and for the State of Washington 	 
	 	 	Residing at  ______________________________	 
	 	 	My commission expires _____________________	 







 






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