Exhibit 4.3


 


FIFTH AMENDMENT TO


SENIOR SECURED NOTES 


 


THIS FIFTH AMENDMENT TO SENIOR SECURED
NOTES (this “Amendment”) is made and entered into as of September 1, 2016 by and among Ener-Core, Inc., a Delaware
corporation (the “Company”), and the undersigned, and amends those certain Senior Secured Notes dated as of
April 23, 2015 (as amended to date, the “Notes”) as issued by the Company pursuant to that certain Securities
Purchase Agreement, dated April 22, 2015, by and among the Company, the “Buyers” identified therein, and the Collateral
Agent identified therein (as amended to date, the “Agreement”). Capitalized terms used herein but not otherwise
defined herein shall have the meanings ascribed to such terms in the Notes.


 


RECITALS


 


WHEREAS, pursuant to Section
15 of the Notes, the written consent of the holders of Notes representing at least a majority of the aggregate principal amount
of the Notes then outstanding, including Empery Asset Master, Ltd. (“Empery”) so long as Empery or any of its
Affiliates holds any Notes (the “Required Holders”), shall be required for any change or amendment or
waiver of any provision of the Notes, provided that any such amendment or waiver does not disproportionately, materially and adversely
affect the rights and obligations of any Holder relative to the comparable rights and obligations of the other Holders;


 


WHEREAS, any amendment effected
in accordance with Section 15 of the Notes is binding upon all holders of Notes; and


 


WHEREAS, the parties hereto
wish to amend the Notes as set forth below in order to facilitate the Company’s efforts to consummate financing activities
to support working capital needs.


 


AGREEMENT


 


NOW, THEREFORE, in consideration
of the mutual covenants herein contained and other good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties, intending to be legally bound, agree as follows:  


 


ARTICLE I

AMENDMENTS TO THE NOTES


 


Section 1.1 Additional Permitted
Indebtedness. Section 29(t) of the Notes is hereby amended and restated as follows:


 


“(t) “Permitted Indebtedness”
means (i) Indebtedness evidenced by this Note and the Other Notes, (ii) trade payables incurred in the ordinary course of business
consistent with past practice, (iii) Indebtedness secured by Permitted Liens described in clauses (iv) of the definition of Permitted
Liens, (iv) deemed Indebtedness arising from one or more operating leases, including, without limitation, the leases for one or
more test turbines from Dresser-Rand, but only if such lease, if secured, is secured solely by such test turbine, (v) Indebtedness
listed on Schedule 29(t) attached hereto, (vi) Indebtedness incurred pursuant to the Backstop Agreement, (vii) Indebtedness evidence
by the Bridge Notes (as defined in the Securities Purchase Agreement, as amended to date).”


 


Section 1.2 Redemption Date.
The first sentence of Section 7 of the Notes is hereby amended and restated as follows:


 


“At any time from and after December 31,
2016, the Holder shall have the right, in its sole and absolute discretion, at any time or times, to require that the Company redeem
(a “Holder Optional Redemption”) all or any portion of the Conversion Amount of this Note then outstanding by
delivering written notice thereof (a “Holder Optional Redemption Notice” and the date the Holder delivers such
notice, the “Holder Optional Redemption Notice Date”) to the Company, which notice shall state (i) the portion
of this Note that is being redeemed and (ii) the date on which the Holder Optional Redemption shall occur, which date shall be
not less than three (3) Business Days from the Holder Optional Redemption Notice Date (the “Holder Optional Redemption
Date”).”


 


Section 1.3 Further Private
Offering. Section 14(l) of the Notes is hereby amended and restated as follows:


 


“(l) Further Private Offering.
Prior to December 31, 2016, the Company shall consummate a Further Private Offering.”


 






     


    


    




 


ARTICLE II

MISCELLANEOUS


 


Section 2.1 Effect of this Amendment.
This Amendment shall form a part of each Note for all purposes, and each holder thereof shall be bound hereby. This Amendment shall
only be deemed to be in full force and effect from and after both the execution of this Amendment by the parties hereto and the
execution of agreements substantially identical to this Amendment by the Company and holders of Notes at least a majority of the
aggregate principal amount of the Notes then outstanding, including Empery, constituting the Required Holders. From and after such
effectiveness, any reference to the Notes shall be deemed to be a reference to the Notes as amended hereby. Except as specifically
amended as set forth herein, each term and condition of the Notes shall continue in full force and effect.


 


Section 2.2 Entire Agreement.
This Amendment, together with the Notes, contains the entire agreement of the parties and supersedes any prior or contemporaneous
written or oral agreements between them concerning the subject matter of this Amendment.


 


Section 2.3 Governing Law.
This Amendment shall be governed by the internal law of the State of New York.


 


Section 2.4 Counterparts.
This Amendment may be executed in any number of counterparts and by different parties hereto in separate counterparts, each of
which when so executed and delivered shall be deemed an original, but all such counterparts together shall constitute but one and
the same instrument; signature pages may be detached from multiple separate counterparts and attached to a single counterpart so
that all signature pages are physically attached to the same document. This Amendment may be executed by fax or electronic mail,
in PDF format, and no party hereto may contest this Amendment’s validity solely because a signature was faxed or otherwise
sent electronically.


 


[Signature Pages Follow]





 






     


    


    




 


IN WITNESS WHEREOF, the parties
hereto have executed this Fifth Amendment to Senior Secured Notes as of the date first written above.


 


	 	COMPANY:
	 	 
	 	ENER-CORE, INC.
	 	 	 
	 	By:	 
	 	 	Name: 
	 	 	Title:  


 






    


[Signature Page to Fifth Amendment to Senior Secured
Notes—April 2015]







    


    

 











IN WITNESS WHEREOF, the parties
hereto have executed this Fifth Amendment to Senior Secured Notes as of the date first written above.


 


	 	
        HOLDER:

	 	 	 
	 	By:	 
	 	 	Name: 
	 	 	Title: 


 




 





[Signature Page to Fifth Amendment to Senior Secured
Notes—April 2015]