Exhibit 10.4


 


June
1, 2017


 


KBL
Merger Corp. IV


527
Stanton Christiana Rd.


Newark,
DE 19713


Attn:
Marlene Krauss, M.D.


 


Ladenburg
Thalmann & Co. Inc.


277
Park Avenue, 26th Floor


New
York, New York 10172


As
Representative of the Several Underwriters named in


Schedule
A  of the Underwriting Agreement


 


	Re:	Initial
    Public Offering


 


Gentlemen:


 


This
letter (this “Letter Agreement”) is being delivered to you in accordance with the Underwriting Agreement
(the “Underwriting Agreement”) proposed to be entered into by and between KBL Merger Corp. IV, a Delaware
corporation (the “Company”), and Ladenburg Thalmann & Co. Inc. as representative (the “Representative”)
of the several underwriters named therein (the “Underwriters”), relating to an underwritten initial
public offering (the “Public Offering”), of 10,000,000 of the Company’s units (the “Units”),
each comprised of one share of the Company’s common stock, par value $0.0001 per share (the “Common Stock”),
one right to receive one-tenth of one share of Common Stock (each, a “Right”), and one warrant (each,
a “Warrant”). Each Warrant entitles the holder thereof to purchase one-half of one share of Common Stock
at a price of $11.50 per whole share, subject to adjustment. The Units shall be sold in the Public Offering pursuant to a registration
statement on Form S-1 and prospectus (the “Prospectus”) filed by the Company with the Securities and
Exchange Commission (the “Commission”) and the Company shall apply to have the Units listed on the Nasdaq
Capital Market. Certain capitalized terms used herein are defined in Section 11 hereof.


 


In
order to induce the Company and the Underwriters to enter into the Underwriting Agreement and to proceed with the Public Offering
and for other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, KBL IV Sponsor LLC
(the “Sponsor”), the undersigned individuals, each of whom is a director or officer to the Company (together
with the Sponsor, each an “Insider” and collectively, the “Insiders”), hereby
agree with the Company as follows:


 


1.
Each Insider agrees that if the Company seeks stockholder approval of a proposed Business Combination, then in connection with
such proposed Business Combination, it, he or she shall (i) vote any shares of Common Stock owned by it, him or her in favor of
such proposed Business Combination and (ii) not redeem any shares of Common Stock owned by it, him or her in connection with such
stockholder approval. If the Company engages in a tender offer in connection with any proposed Business Combination, each Insider
agrees that it, he or she will not seek to sell its, his or her shares of Common Stock owned by it, him or her to the Company
in connection with such tender offer.


 


2.
Each Insider agrees that in the event that the Company fails to consummate a Business Combination (as defined in the Underwriting
Agreement) within the time period set forth in the Company’s amended and restated certificate of incorporation, as the same
may be amended from time to time, each Insider shall take all reasonable steps to cause the Company to (i) cease all operations
except for the purpose of winding up, (ii) as promptly as reasonably possible but not more than 10 business days thereafter
redeem 100% of the Common Stock sold as part of the Units in the Public Offering (the “Offering Shares”),
at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account, including interest
(which interest shall be net of taxes payable and less up to $50,000 of interest to pay dissolution expenses), divided by the
number of then outstanding public shares, which redemption will completely extinguish Public Stockholders’ rights as stockholders
(including the right to receive further liquidation distributions, if any) and (iii) as promptly as reasonably possible following
such redemption, subject to the approval of the Company’s remaining stockholders and the Company’s board of directors,
dissolve and liquidate, subject in the cases of clauses (ii) and (iii) above to the Company’s obligations under Delaware
law to provide for claims of creditors and other requirements of applicable law. Each Insider agrees not to propose any amendment
to the Company’s amended and restated certificate of incorporation that would affect the substance or timing of the Company’s
obligation to redeem the Offering Shares in connection with a Business Combination or if the Company does not complete a Business
Combination within the time period then set forth in the Company’s amended and restated certificate of incorporation, unless
the Company provides its public stockholders with the opportunity to redeem their shares of Common Stock upon approval of any
such amendment at a per-share price, payable in cash, equal to the aggregate amount then on deposit in the Trust Account including
interest (which interest shall be net of taxes payable), divided by the number of then outstanding public shares.


 




     


     


    

 


Each
Insider acknowledges that it, he or she has no right, title, interest or claim of any kind in or to any monies held in the Trust
Account or any other asset of the Company as a result of any liquidation of the Company and hereby waives any claim such Insider
may have in the future as a result of, or arising out of, any contracts or agreements with the Company and will not seek recourse
against the Trust Fund for any reason whatsoever except in each case with respect to the Insider’s right to a pro rata interest
in the proceeds held in the Trust Fund for any Offering Shares such Insider may hold.


 


3.
Subject to the provisions set forth in paragraphs 7(a) and (b) below, during the period commencing on the effective date of
the Underwriting Agreement and ending 180 days after such date, the Sponsor and each Insider shall not (i) sell, offer to
sell, contract or agree to sell, hypothecate, pledge, grant any option to purchase or otherwise dispose of or agree to
dispose of, directly or indirectly, file (or participate in the filing of) a registration statement with the Commission or
establish or increase a put equivalent position or liquidate or decrease a call equivalent position within the meaning of
Section 16 of the Securities Exchange Act of 1934, as amended, and the rules and regulations of the Commission promulgated
thereunder, with respect to any Units, shares of Common Stock, Rights, Warrants or any securities convertible into, or
exercisable, or exchangeable for, shares of Common Stock owned by it, if any, (ii) enter into any swap or other arrangement
that transfers to another, in whole or in part, any of the economic consequences of ownership of any Units, shares of Common
Stock, Rights, Warrants or any securities convertible into, or exercisable, or exchangeable for, shares of Common Stock owned
by it, if any, whether any such transaction is to be settled by delivery of such securities, in cash or otherwise, or (iii)
publicly announce any intention to effect any transaction specified in clause (i) or (ii). The foregoing sentence shall not
apply to the registration of the offer and sale of Units contemplated by the Underwriting Agreement and the sale of the Units
to the Underwriters. The Sponsor and each of the Insiders acknowledges and agrees that, prior to the effective date of any
release or waiver, of the restrictions set forth in this paragraph 3 or paragraph 7 below, the Company shall announce the
impending release or waiver by press release through a major news service at least two business days before the effective
date of the release or waiver. Any release or waiver granted shall only be effective two business days after the publication
date of such press release. The provisions of this paragraph will not apply if (i) the release or waiver is effected solely
to permit a transfer of securities that is not for consideration and (ii) the transferee has agreed in writing to be bound by
the same terms described in this Letter Agreement to the extent and for the duration that such terms remain in effect at the
time of the transfer.


 


4.
In the event of the liquidation of the Trust Account, the Sponsor (the “Indemnitor”) agrees
to indemnify and hold harmless the Company against any and all loss, liability, claim, damage and expense whatsoever
(including, but not limited to, any and all legal or other expenses reasonably incurred in investigating, preparing or
defending against any litigation, whether pending or threatened, or any claim whatsoever) to which the Company may become
subject as a result of any claim by (i) any third party for services rendered or products sold to the Company or
(ii) a prospective target business with which the Company has entered into an acquisition agreement (a
“Target”); provided, however, that such indemnification of the Company by
the Indemnitor shall apply only to the extent necessary to ensure that such claims by a third party for services rendered or
products sold to the Company or a Target do not reduce the amount of funds in the Trust Account to below (i) $10.10 per
Offering Share or (ii) such lesser amount per Offering Share held in the Trust Account due to reductions in the value of the
trust assets as of the date of the liquidation of the Trust Account, in each case, net of the amount of interest earned on
the property in the Trust Account which may be withdrawn to pay taxes, except as to any claims by a third party who executed
a waiver of any and all rights to seek access to the Trust Account and except as to any claims under the Company’s
indemnity of the Underwriters against certain liabilities, including liabilities under the Securities Act of 1933, as
amended. In the event that any such executed waiver is deemed to be unenforceable against such third party, the
Indemnitor shall not be responsible to the extent of any liability for such third party claim. The Indemnitor shall have the
right to defend against any such claim with counsel of its choice reasonably satisfactory to the Company if, within 15 days
following written receipt of notice of the claim to the Indemnitor, the Indemnitor notifies the Company in writing that it
shall undertake such defense.


 



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5.
To the extent that the Underwriters do not exercise their over-allotment option in full to purchase an additional 1,500,000
Units within 45 days from the date of the Prospectus (and as further described in the Prospectus), the Sponsor agrees that it
shall forfeit, at no cost, a number of Founder Shares in the aggregate equal to 375,000 multiplied by a fraction,
(i) the numerator of which is 1,500,000 minus the number of Units, if any, purchased by the Underwriters upon the
exercise of their over-allotment option, and (ii) the denominator of which is 1,500,000. The forfeiture will be adjusted
to the extent that the over-allotment option is not exercised in full by the Underwriters so that the stockholders prior to
the Public Offering will own an aggregate of 20.0% of the Company’s issued and outstanding shares of Common Stock after
the Public Offering (not including any Private Placement Shares). The Sponsor further agrees that to the extent that the size
of the Public Offering is increased or decreased, the Company will purchase or sell shares of Common Stock or effect a stock
dividend or share contribution back to capital, as applicable, immediately prior to the consummation of the Public Offering
in such amount as to maintain the ownership of the stockholders prior to the Public Offering at 20.0% of its issued and
outstanding shares of Common Stock upon the consummation of the Public Offering (not including any Private Placement Shares).
In connection with such increase or decrease in the size of the Public Offering, then (A) the references to 1,500,000 in the
numerator and denominator of the formula in the first sentence of this paragraph shall be changed to a number equal to 15% of
the number of shares included in the Units issued in the Public Offering and (B) the reference to 375,000 in the formula set
forth in the first sentence of this paragraph shall be adjusted to such number of shares of the Common Stock that the Sponsor
would have to return to the Company in order to hold (together with all of the pre-Public Offering stockholders) an aggregate
of 20.0% of the Company’s issued and outstanding shares after the Public Offering (not including any Private Placement
Shares).


 


6.
Each officer of the Company agrees not to participate in the formation of, or become an officer or director of, any other
blank check company until the Company has entered into a definitive agreement with respect to a Business Combination or the
Company has failed to complete a Business Combination within the time period set forth in the Company’s amended and
restated certificate of incorporation, as the same may be amended from time to time.


 


7.
(a) Each Insider (if such Insider owns any Founder Shares) agrees that it, he or she shall not Transfer (as defined
below) any Founder Shares until the earlier of (i) one year after the completion of a Business Combination or (ii) on such
earlier date as provided in clauses (x) or (y) below if, subsequent to a Business Combination, (x) the last sale price of the
Common Stock equals or exceeds $12.00 per share (as adjusted for stock splits, stock dividends, reorganizations,
recapitalizations and the like) for any 20 trading days within any 30-trading day period commencing at least 150 days after a
Business Combination or (y) the date following the completion of a Business Combination on which the Company completes a
liquidation, merger, stock exchange or other similar transaction that results in all of the Company’s stockholders
having the right to exchange their shares of Common Stock for cash, securities or other property (the “Founder
Shares Lock-up Period”).


 


(b)
The Sponsor agrees that it shall not effectuate any Transfer of Private Placement Shares, Private Placement Rights, Private Placement
Warrants or Common Stock issued or issuable upon the exercise of the Private Placement Warrants or upon the conversion of the
Private Placement Rights, until 30 days after the completion of a Business Combination (the “Private Placement Lock-up
Period”, together with the Founder Shares Lock-up Period, the “Lock-up Periods”).


 


(c)
Notwithstanding the provisions set forth in Sections 7(a) and (b), Transfers of the Founder Shares, Private Placement Shares,
Private Placement Rights, Private Placement Warrants and shares of Common Stock issued or issuable upon the exercise of the Private
Placement Warrants or upon the conversion of the Private Placement Rights are permitted to (a) to the Company’s officers
or directors, any affiliates or family members of any of the Company’s officers or directors, any members or partners of
the Sponsor, or any affiliates of the Sponsor or any of its members or partners; (b) in the case of an individual, by gift to
one of the members of the individual’s immediate family or to a trust, the beneficiary of which is a member of one of the
individual’s immediate family, an affiliate of such person or to a charitable organization; (c) in the case of an individual,
by virtue of laws of descent and distribution upon death of the individual; (d) in the case of an individual, pursuant to a qualified
domestic relations order; (e) by private sales or transfers made in connection with the consummation of a Business Combination
at prices no greater than the price at which the securities were originally purchased; (f) in the event of a Company liquidation
prior to a completion of a Business Combination; (g) to the Company for no value for cancellation; or (h) by virtue of the laws
of Delaware or either of the Sponsors’ operating agreements; provided, however, that in the case of clauses (a) through
(f) and (h), these permitted transferees must enter into a written agreement agreeing to be bound by these transfer restrictions
(including provisions relating to voting, the trust account and liquidation distributions described elsewhere in this letter or
the Registration Statement). Any Transfer made in contravention of this Letter Agreement shall be null and void.


 



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8.
Each Insider represents and warrants that it, he or she has never been suspended or expelled from membership in any securities
or commodities exchange or association or had a securities or commodities license or registration denied, suspended or revoked.
As applicable, each Insider’s biographical information furnished to the Company is true and accurate in all material respects
and does not omit any material information with respect to the undersigned’s background. Each Insider’s questionnaire
furnished to the Company is true and accurate in all material respects. As applicable, each Insider represents and warrants (severally,
and not jointly with the other Insiders) that: the undersigned is not subject to or a respondent in any legal action for, any
injunction, cease-and-desist order or order or stipulation to desist or refrain from any act or practice relating to the offering
of securities in any jurisdiction; the undersigned has never been convicted of, or pleaded guilty to, any crime (i) involving
fraud, (ii) relating to any financial transaction or handling of funds of another person, or (iii) pertaining to any
dealings in any securities; and the undersigned is not currently a defendant in any such criminal proceeding.


 


9.
(a) Except as disclosed in the Prospectus, neither the Insiders nor any of their respective affiliates shall receive from the
Company any finder’s fee, reimbursement or cash payments for any services rendered to the Company prior to or in connection
with the consummation of an initial Business Combination. 


 


(b)
Commencing on the effective date of the Prospectus for the Offering and continuing until the earlier of (i) the consummation by
the Company of a Business Combination or (ii) the Company’s liquidation as described in the Prospectus, the Sponsor shall
make available to the Company, at no charge, certain office space and administrative and support services as may be required by
the Company from time to time, situated at 527 Stanton Christiana Rd., Newark, DE 19713 (or any successor locations). 


  


10.
Each Insider has full right and power, without violating any agreement to which it, he or she is bound (including, without limitation,
any non-competition or non-solicitation agreement with any employer or former employer), to enter into this Letter Agreement and,
as applicable, to serve as an officer or a director on the board of directors of the Company and hereby consents to being named
in the Prospectus as an officer or a director or director nominee of the Company.


 


11.
As used herein, (i) “Business Combination” shall mean a merger, capital stock exchange, asset acquisition,
stock purchase, reorganization or similar initial business combination, involving the Company and one or more businesses or entities;
(ii) “Founder Shares” shall mean the 2,875,000 shares (up to 375,000 of which are subject to forfeiture,
if the underwriters’ over-allotment option is not exercised in full) of Common Stock of the Company initially acquired by
the Sponsor for an aggregate purchase price of $25,000, prior to the consummation of the Public Offering; (iii) “Private
Placement Shares,” “Private Placement Rights” and “Private Placement Warrants”
shall mean the shares of Common Stock, Rights and Warrants, underlying the 450,000 Units that will be purchased by the Sponsor
and the representative of the underwriters for an aggregate purchase price of $4,500,000 or $10.00 per Unit, in a private placement
that shall occur simultaneously with the consummation of the Public Offering; (iv) “Public Stockholders”
shall mean the holders of securities issued in the Public Offering; (v) “Trust Account” shall mean
the trust fund into which a portion of the net proceeds of the Public Offering shall be deposited; and (vi) “Transfer”
shall mean the (a) sale of, offer to sell, contract or agreement to sell, hypothecate, pledge, grant of any option to purchase
or otherwise dispose of or agreement to dispose of, directly or indirectly, or establishment or increase of a put equivalent position
or liquidation with respect to or decrease of a call equivalent position within the meaning of Section 16 of the Exchange
Act and the rules and regulations of the Commission promulgated thereunder with respect to, any security, (b) entry into
any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of
any security, whether any such transaction is to be settled by delivery of such securities, in cash or otherwise, or (c) public
announcement of any intention to effect any transaction specified in clause (a) or (b).


 



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12.
(a) This Letter Agreement constitutes the entire agreement and understanding of the parties hereto in respect of the subject matter
hereof and supersedes all prior understandings, agreements, or representations by or among the parties hereto, written or oral,
to the extent they relate in any way to the subject matter hereof or the transactions contemplated hereby. This Letter Agreement
may not be changed, amended, modified or waived (other than to correct a typographical error) as to any particular provision,
except by a written instrument executed by all parties hereto.


 


(b)
Each Insider agrees and acknowledges that: (i) each of the Underwriters and the Company would be irreparably injured in the
event of a breach by such Insider of his, her or its obligations (as applicable) under Sections 1, 2, 3, 4, 5, 6, 7(a), 7(b),
and 9 of this Letter Agreement, (ii) monetary damages may not be an adequate remedy for such breach and (iii) the non-breaching
party shall be entitled to seek injunctive relief, in addition to any other remedy that such party may have in law or in equity,
in the event of such breach.


 


13.
No party hereto may assign either this Letter Agreement or any of its rights, interests, or obligations hereunder without the
prior written consent of the other parties. Any purported assignment in violation of this Section shall be void and ineffectual
and shall not operate to transfer or assign any interest or title to the purported assignee. This Letter Agreement shall be binding
on the Insiders and their respective successors and permitted assigns.


  


14.
This Letter Agreement shall be governed by and construed and enforced in accordance with the laws of the State of New York, without
giving effect to conflicts of law principles that would result in the application of the substantive laws of another jurisdiction.
The parties hereto (i) all agree that any action, proceeding, claim or dispute arising out of, or relating in any way to,
this Letter Agreement shall be brought and enforced in the courts of New York City, in the State of New York, and irrevocably
submits to such jurisdiction and venue, which jurisdiction and venue shall be exclusive and (ii) waives any objection to
such exclusive jurisdiction and venue or that such courts represent an inconvenient forum. 


  


15.
Any notice, consent or request to be given in connection with any of the terms or provisions of this Letter Agreement shall be
in writing and shall be sent by express mail or similar private courier service, by certified mail (return receipt requested),
by hand delivery or facsimile transmission.


 


16.
This Letter Agreement shall terminate on the earlier of (i) the expiration of the Lock-up Periods or (ii) the liquidation
of the Company; provided, however, that the last paragraph of Section 2 and Section 4 of this Letter Agreement
shall survive such liquidation.


 


[Signature
page follows]


 



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Sincerely,


 


KBL
IV SPONSOR, LLC


 


	By:	 /s/
    Marlene Krauss	 
	 	Name: Marlene Krauss, M.D.	 
	 	Title: Managing Member	 


 


	/s/
Marlene Krauss	 
	Marlene Krauss, M.D.	 


 


	/s/
Joseph A. Williamson	 
	Joseph A. Williamson	 


 


	/s/
George Hornig	 
	George Hornig	 


 


	/s/
Sherrill Neff	 
	Sherrill Neff	 


 


	/s/
Andrew Sherman	 
	Andrew Sherman	 
	 	 
	Acknowledged and Agreed:	 
	 	 
	KBL Merger Corp IV	 
	 	 
	By:	/s/ Marlene Krauss	 
	 	Name: Marlene Krauss, M.D.	 
	 	Title: Chief Executive Officer	 


 


[Signature
Page to Insider Letter Agreement]


 


 


6