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	 	 	Annual Rent	 	 	 	 	 	Monthly
    Installment	 
	from	 	through	 	
 Footage
	 	 	
 Per
                                         Square Foot
	 	 	Annual
    Rent	 	 	
 of
                                         Rent
	 
	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:	/s/ Cathleen Meyer	 	By:	/s/
    James N. Harmon               
	 	Cathleen Meyer, Vice President	 	Its:	Chief
    Financial Officer
	 	 	 	 	 
	Date:	11/3/16	 	Date:	10/28/16


 


CORPORATE ACKNOWLEDGMENT


 


	STATE OF WASHINGTON         	)
	 	)  ss.
	COUNTY OF KING	)


 


On
this 28th day of October, 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]	/s/ Arika Smithhisler
	 	(Signature)


 


	 	 Arika Smithhisler
	 	(Please print name legibly)





 





	 	NOTARY PUBLIC in and for the State of Washington





	 	Residing at	Eaglewood, WA






	 	My commission expires	7/29/2020 


 






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CORPORATE ACKNOWLEDGMENT


 


	STATE OF WASHINGTON         	)
	 	)  ss.
	COUNTY OF KING	)


 





On
this 3rd day of November, 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]	/s/ Rachel Johnson
	 	(Signature)


 


	 	Rachel Johnson
	 	(Please print name legibly)





 





	 	NOTARY PUBLIC in and for the State of Washington





	 	Residing at	Seattle, WA






	 	My commission expires	 8/6/19


 






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