Exhibit 10.15.4

THIRD AMENDMENT TO LEASE
This Third Amendment to Lease (the "Amendment'), dated June 1, 2016 for
references purposes only, is made and entered into by and between Nassau Land
Company, L.P., a California limited partnership (the "Landlord'), and Resonant,
Inc., a Delaware corporation (the "Tenant'), with reference to the following
facts:
RECITALS:

A.Landlord is the owner of the real property and improvements consisting of
approximately 63,283 square feet of leasable space located in the Castilian
Technical Center situated at 110, 130 and 150 Castilian Drive, Goleta,
California (the "Project'). The building situated at 110 Castilian Drive (the
"Building") currently consists of approximately 25,720 square feet of leasable
space.

B.Landlord and Tenant entered into a Multi-Tenant Industrial Lease dated August
9, 2013 (the "Original Lease"), whereby Landlord leased to Tenant. and Tenant
leased from Landlord, approximately 3,608 square feet of leasable space located
within the Project and commonly known as 110 Castilian Drive, Suite 100, Goleta,
California (the "Original Premises").

C.Landlord and Tenant entered into a written First Amendment to Lease dated
March 20, 2014 expanding the leased Premises to include the space adjacent to
the Original Premises commonly known as Suite 103 located in the Building
consisting of approximately 1,916 leasable square feet (the "Expansion
Premises").

D.Landlord and Tenant entered into a written Second Amendment. Lease dated
September 15, 2014, whereby landlord temporarily leased to Tenant approximately
1,500 square feet of additional leasable space located on the second (2nd) floor
of the Building as outlined in the Site Plan attached as Exhibit A to the Second
Amendment (the "Additional Premises'') for the period commencing September 4,
2014 and ending January 15, 2015.
 
E.Landlord and Tenant wish to amend the leased Premises to include the
Additional Premises and to address other matters, including, without limitation,
changes to the amount of Rent.

F.The parties have agreed to execute this Amendment in order to memorialize
their understandings regarding certain amendments to the Lease.

G.All capitalized terms that appear in this Amendment and are not defined herein
shall have the meaning ascribed thereto in the Lease.

AGREEMENTS:

NOW THEREFORE, the parties hereto, intended to be legally bound, do hereby agree
and further amend the Lease as follows:    
1.     AMENDMENTS TO LEASE. Notwithstanding any other provisions of the Lease to
the contrary, effective as of the date set forth above, the Lease is hereby
amended as follows:

1.1     Delivery Date. Landlord shall deliver the Additional Premises to Tenant,
in its "as is" condition, on June 15, 2016 (the "Addition Delivery Date”).

1.2     Premises. Effective as of the Addition Delivery Date, the Additional
Premises shall be part of the Premises under this Lease, so that the term
"Premises" in this Lease shall refer to the Original Premises plus the Expansion
Premises plus the Additional Premises and the leased Premises shall consist of a
total of 7,024 leaseable square feet through the end of the Addition Term (as
defined below).

1.3     Addition Term. The lease Term for the Additional Premises (the "Addition
Term") shall commence upon the Addition Delivery Date and shall continue on a
month-to-month basis through the expiration of the Lease. Landlord and Tenant
each reserve the right to terminate Tenant's right to lease the Additional
Premises provided notification of such

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termination is at least thirty (30) days prior to the such date of termination.
At the expiration of the Addition Term, Tenant shall return the Additional
Premises to landlord in accordance with Section 25.1 (Surrender of the Premises)
of the Original Lease.

1.4    Tenant shall have no right to sublet, license or assign the right to
lease the Additional Premises.

1.5    Monthly Base Rent. During the Addition Term, the Monthly Base Rent for
the Additional Premises shall be the sum of $1.55 per square feet per month
(NNN) payment in monthly installments of $2,325 .00 (NNN).

1.6    Operating Expenses. Effective throughout the Addition Term, Tenant's
proportionate share of the Building Expenses shall be twenty-seven and 31/100
percent (27.31%) and Tenant's proportionate share of the Project Operating
Expenses shall be eleven and 10/100'percent (11.10%).

2. MISCELLANEOUS.

2.1     In the event of any conflict between the terms of this Amendment and the
terms of the Lease, the terms of this Amendment shall control.

2.2      This Amendment is the entire agreement between the parties with respect
to the subject matter hereof and supersedes all prior contemporaneous oral and
written agreements and discussions with respect to the subject matter hereof.

2.3 Landlord and Tenant represent and warrant that all signatories hereto
signing in a representative capacity have been duly authorized by and on behalf
of their respective principals to execute this Amendment.

AGREED THIS 15th day of August 2016.

LANDLORD:
 
TENANT:
 
 
 
NASSAU LAND COMPANY, L.P.
 
RESONANT INC
a California limited partnership
 
a Delaware corporation
 
 
 
By: Michael Towbes Construction & Development, Inc., a
 
 
California corporation
 
 
Its: General Partner
 
 
 
 
 
By: /s/ MichaelTowbes
 
By: /s/ John M. Philpott
Its: President
 
Its: CFO