Exhibit 4.1


 


AMENDMENT NO. 3 TO AMENDMENT AGREEMENT
AND WAIVER


 


This AMENDMENT NO.
3 TO AMENDMENT AGREEMENT AND WAIVER (this “Amendment”), dated as of March 28, 2019, is made by and between
Ener-Core, Inc., a Delaware corporation, with headquarters located at 30100 Town Center Dr., Suite O-209, Laguna Niguel, California
92677 (the “Company”), and the investor listed on the signature page attached hereto (the “Holder”).


 


RECITALS


 


A. Reference
is made to that certain Securities Purchase Agreement dated as of April 22, 2015, by and among the Company, the Holder (if applicable)
and the other investors (the “April 2015 Other Holders”) listed on the signature pages attached thereto (the
“April 2015 SPA”) and, if applicable, the Senior Secured Notes issued to the Holder pursuant thereto, as amended
and restated on December 2, 2016 pursuant to certain amendment agreements (as amended from time to time prior to the date hereof,
the “April 2015 Notes”);


 


B. Reference
is made to that certain Securities Purchase Agreement dated as of May 7, 2015, by and among the Company, the Holder (if applicable)
and the other investors (the “May 2015 Other Holders” and together with the April 2015 Other Holders, the “Other
Holders” and together with the Holder, the “Holders”) listed on the signature pages attached thereto
(the “May 2015 SPA” and together with the April 2015 SPA, individually, an “SPA” and collectively,
the “SPAs”), and, if applicable, the Senior Secured Notes issued to the Holder pursuant thereto, as amended
and restated on December 2, 2016 pursuant to certain amendment agreements (as amended from time to time prior to the date hereof,
the “May 2015 Notes” and together with the April 2015 Notes, the “2015 Notes”);


 


C. Reference
is made to that certain Amendment Agreement and Waiver dated as of December 31, 2018 by and among the Company and the Holder with
respect to the 2015 Notes and the SPAs (the “December Amendment”); and


 


D. In
compliance with Section 15 of the 2015 Notes and the SPAs, this Amendment shall only be effective upon the execution and delivery
of this Amendment and agreements in form and substance identical to this Amendment (other than with respect to the identity of
the Holder and any provision regarding the reimbursement of legal fees) (the “Other Agreements” and together
with this Amendment, the “Amendments”) by Other Holders of the 2015 Notes (each an “Other Holder”)
representing on the Closing Date at least the Required Holders (as defined in each of the 2015 Notes) (such time, the “Effective
Time”).


 


AGREEMENT


 


NOW THEREFORE,
in consideration of the foregoing mutual premises and the covenants and agreements hereinafter set forth, and for other good and
valuable consideration, the receipt, and legal adequacy of which is hereby acknowledged, the parties hereto, intending to be legally
bound, hereby agree as follows:


 


ARTICLE I


AMENDMENT


 


1. Amendment
of December Amendment. All references to the date “January 31, 2019” set forth in the December Amendment are hereby
amended to instead refer to the date “April 30, 2019”, and all references to the date “February 1, 2019” set
forth in the December Amendment are hereby amended to instead refer to the date “May 1, 2019”. Capitalized terms used
herein and not otherwise defined herein shall have the respective meanings set forth in the December Amendment.


 






     


     


    

 


article
II

MISCELLANEOUS


 


1. Effect
of this Amendment. This Amendment shall form a part of the 2015 Notes and SPAs for all purposes, and each holder of 2015 Notes
and each party to the SPAs 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 Amendments substantially identical to this Amendment
by the Company and “Holders” holding at least a majority of the aggregate principal amount of the 2015 Notes outstanding,
including the Lead Investor, as well as the Collateral Agent, that, together with undersigned, constitute the Required Holders
under each of the 2015 Notes and SPAs. From and after such effectiveness, any reference to the 2015 Notes and the SPAs shall be
deemed to be a reference to the 2015 Notes and SPAs, as amended hereby. Except as specifically amended as set forth herein, each
term and condition of the 2015 Notes and SPAs shall continue in full force and effect.


 


2. Entire
Agreement. This Amendment, together with the SPAs and 2015 Notes, as amended and/or amended and restated to date, contains
the entire agreement of the parties with respect to the matters contemplated hereby and thereby, and supersedes any prior or contemporaneous
written or oral agreements between them concerning the subject matter of this Amendment.


 


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


 


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 Page Follows]


 






    2


     


    

 





IN WITNESS WHEREOF,
the Holder and the Company have caused their respective signature pages to this Amendment to be duly executed as of the date first
written above.


 


	 	COMPANY:
	 	 
	 	ENER-CORE, INC.
	 	 
	 	By:	

	 	 	Name: 	Domonic J. Carney
	 	 	Title: 	Chief Financial Officer


 


Signature
Page to amendment no. 3 to Amendment Agreement and Waiver—2015 Notes


 






     


     


    







 


	 	HOLDER:
	 	 
	 	By:	

	 	 	Name: 	 
	 	 	Title: 	 


 


Signature
Page to amendment no. 3 to Amendment Agreement and Waiver—2015 Notes