Exhibit 10.1


 


June 29, 2021


 


Mountain Crest Acquisition Corp. IV


311 West 43rd Street, 12th Floor


New York, NY 10036


 


Network 1 Financial Securities, Inc.


2 Bridge Ave #241


Red Bank, NJ 07701


 


	 	Re:	Initial
    Public Offering


 


Gentlemen:


 


This letter is being delivered
to you in accordance with the Underwriting Agreement (the “Underwriting Agreement”) entered into by and between
Mountain Crest Acquisition Corp. IV, a Delaware corporation (the “Company”), and Network 1 Financial Securities, Inc.,
as Representative (the “Representative”) of the several underwriters named on Schedule A thereto (the “Underwriters”),
relating to an underwritten initial public offering (the “IPO”) of the Company’s units (the “Units”),
each comprised of one share of common stock of the Company, $0.0001 par value (the “Common Stock”) and one
right to receive one-tenth (1/10) of one share of Common Stock (the “Rights”). Certain capitalized terms used
herein are defined in paragraph 16 hereof.


 


In order to induce the Company
and the Underwriters to enter into the Underwriting Agreement and to proceed with the IPO, and in recognition of the benefit that such
IPO will confer upon the undersigned as a shareholder of the Company, and for other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged, the undersigned hereby agrees with the Company as follows:


 


1. If the Company solicits
approval of its shareholders of a Business Combination, the undersigned will vote all shares of Common Stock beneficially owned by him,
her or it, whether acquired before, in or after the IPO, in favor of such Business Combination.


 


2. (a) Unless the Company’s
shareholders are previously given the option to redeem their shares in connection with amending applicable documents to extend the time
that the Company has to complete a Business Combination and the Company fails to consummate a Business Combination within 12 months from
the closing of the Company’s IPO (or, in the event that the Company extended the period of time to consummate a business combination
up to 18 months from the closing of the Company’s IPO, as specified in the Company’s amended and restated certificate of
incorporation), the undersigned shall take all reasonable steps to (i) cause the Trust Fund to be liquidated and distributed to
the holders of the IPO Shares and (ii) cause the Company to liquidate as soon as reasonably practicable.


 


(b) The undersigned hereby
waives any and all right, title, interest or claim of any kind in or to any distribution of the Trust Fund and any remaining net assets
of the Company as a result of such liquidation with respect to his, her or its Insider Shares including any shares underlying the Private
Units (“Claim”) and hereby waives any Claim the undersigned 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. The
undersigned acknowledges and agrees that there will be no distribution from the Trust Fund with respect to any Rights underlying the
Private Units, all of which will terminate on the Company’s liquidation.


 


3. In the event of the liquidation
of the Trust Fund, Mountain Crest Holdings IV LLC agrees to indemnify and hold harmless the Company against any and all loss, liability,
claims, 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) which the Company may become subject
as a result of any claim by any target business or vendor or other person who is owed money by the Company for services rendered or products
sold or contracted for, but only to the extent necessary to ensure that such loss, liability, claim, damage or expense does not reduce
the amount of funds in the Trust Fund; provided that such indemnity shall not apply if such target business, vendor
or other person has executed an agreement waiving any claims against the Trust Fund.


 






     


     


    

 


4. In the event that the Company
does not consummate a Business Combination and must liquidate and its remaining net assets are insufficient to complete such liquidation,
Mountain Crest Holdings IV LLC agrees to advance such funds necessary to complete such liquidation and agrees not to seek recourse for
such expenses.


 


5. The undersigned will escrow
all of his, her or its Insider Shares pursuant to the terms of a Stock Escrow Agreement, which the Company will enter into with the undersigned
and an escrow agent acceptable to the Company. After the underwriter exercises its over-allotment option in full, the remaining portion
of the underwriter’s over-allotment option is canceled, or the underwriter’s over-allotment option terminates, the undersigned
agrees to cancel a portion of the undersigned’s Insider Shares such that the total number of Insider Shares equals (i) .25
multiplied by (ii) the number of Units sold in the IPO.


 


6. The undersigned agrees that
until the Company consummates a Business Combination, the undersigned’s Private Units will be subject to the transfer restrictions
described in the Subscription Agreement relating to the undersigned’s Private Units.


 


7. In order to minimize potential
conflicts of interest which may arise from multiple affiliations, the undersigned agrees to present to the Company for its consideration,
prior to presentation to any other person or entity, any suitable opportunity to acquire a target business, until the earlier of the
consummation by the Company of a Business Combination or the liquidation of the Company, subject to any pre-existing fiduciary and contractual
obligations the undersigned might have.


 


8. The undersigned acknowledges
and agrees that prior to entering into a Business Combination with a target business that is affiliated with any Insiders of the Company
or their affiliates, including any company that is a portfolio company of, or otherwise affiliated with, or has received financial investment
from, an entity with which any Insider or their affiliates is affiliated, such transaction must be approved by a majority of the Company’s
disinterested independent directors and the Company must obtain an opinion from an independent investment banking firm that such Business
Combination is fair to the Company’s unaffiliated shareholders from a financial point of view.


 


9. Neither the undersigned,
any member of the family of the undersigned, nor any affiliate of the undersigned will be entitled to receive and will not accept any
compensation or other cash payment prior to, or for services rendered in connection with, the consummation of the Business Combination; provided that
the Company shall be allowed to repay working capital loans made by the undersigned to the Company in cash upon consummation of the Business
Combination. Notwithstanding the foregoing, the undersigned and any affiliate of the undersigned shall be entitled to reimbursement from
the Company for their out-of-pocket expenses incurred in connection with identifying, investigating and consummating a Business Combination.


 


10. Neither the undersigned,
any member of the family of the undersigned, nor any affiliate of the undersigned will be entitled to receive or accept a finder’s
fee or any other compensation in the event the undersigned, any member of the family of the undersigned or any affiliate of the undersigned
originates a Business Combination.


 


11. Each of the undersigned
officers and directors agrees to be a director or officer, as applicable of the Company until the earlier of the consummation by the
Company of a Business Combination or the liquidation of the Company. The undersigned’s biographical information previously furnished
to the Company and the Representative is true and accurate in all material respects, does not omit any material information with respect
to the undersigned’s biography and contains all of the information required to be disclosed pursuant to Item 401 of Regulation
S-K, promulgated under the Securities Act of 1933.]3 The FINRA Questionnaire of each of the undersigned officers and
directors previously furnished to the Company and the Representative is true and accurate in all material respects. Each of the undersigned
represents and warrants that:


  


	 	(a)	He, she or
    it has never had a petition under the federal bankruptcy laws or any state insolvency law been filed by or against (i) him,
    her or it, or any partnership in which he or she was a general partner at or within two years before the time of filing; or (ii) any
    corporation or business association of which he or she was an executive officer at or within two years before the time of such filing;








  


	 	(b)	He, she or
    it has never had a receiver, fiscal agent or similar officer been appointed by a court for his business or property, or any such
    partnership;


 






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	 	(c)	He, she or
    it has never been convicted of fraud in a civil or criminal proceeding;


 


	 	(d)	He, she or
    it has never been convicted in a criminal proceeding or named the subject of a pending criminal proceeding (excluding traffic violations
    and minor offenses);


 


	 	(e)	He, she or
    it has never been the subject of any order, judgment or decree, not subsequently reversed, suspended or vacated, of any court of
    competent jurisdiction, permanently or temporarily enjoining or otherwise limiting him, her or it from (i) acting as a futures
    commission merchant, introducing broker, commodity trading advisor, commodity pool operator, floor broker, leverage transaction merchant,
    any other person regulated by the Commodity Futures Trading Commission (“CFTC”) or an associated person of any of the
    foregoing, or as an investment adviser, underwriter, broker or dealer in securities, or as an affiliated person, director or employee
    of any investment company, bank, savings and loan association or insurance company, or from engaging in or continuing any conduct
    or practice in connection with any such activity; or (ii) engaging in any type of business practice; or (iii) engaging
    in any activity in connection with the purchase or sale of any security or commodity or in connection with any violation of federal
    or state securities or federal commodities laws;


 


	 	(f)	He, she, or
    it has never been the subject of any order, judgment or decree, not subsequently reversed, suspended or vacated, of any federal or
    state authority barring, suspending or otherwise limiting for more than 60 days his, her or its right to engage in any activity described
    in 11(e)(i) above, or to be associated with persons engaged in any such activity;


 


	 	(g)	He, she, or
    it has never been found by a court of competent jurisdiction in a civil action or by the SEC to have violated any federal or state
    securities law, where the judgment in such civil action or finding by the SEC has not been subsequently reversed, suspended or vacated;


 


	 	(h)	He, she, or
    it has never been found by a court of competent jurisdiction in a civil action or by the CFTC to have violated any federal commodities
    law, where the judgment in such civil action or finding by the CFTC has not been subsequently reversed, suspended or vacated;


 


	 	(i)	He, she, or
    it has never been the subject of, or a party to, any Federal, State or foreign judicial or administrative order, judgment, decree
    or finding, not subsequently reversed, suspended or vacated, relating to an alleged violation of (i) any Federal, State or foreign
    securities or commodities law or regulation, (ii) any law or regulation respecting financial institutions or insurance companies
    including, but not limited to, a temporary or permanent injunction, order of disgorgement or restitution, civil money penalty or
    temporary or permanent cease-and desist order, or removal or prohibition order or (iii) any law or regulation prohibiting mail
    or wire fraud or fraud in connection with any business entity;


 


	 	(j)	He, she or
    it has never been the subject of, or party to, any sanction or order, not subsequently reversed, suspended or vacated, or any self-regulatory
    organization, any registered entity, or any equivalent exchange, association, entity or organization that has disciplinary authority
    over its members or persons associated with a member;


 






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	 	(k)	He, she or
    it has never been convicted of any felony or misdemeanor: (i) in connection with the purchase or sale of any security; (ii) involving
    the making of any false filing with the SEC; or (iii) arising out of the conduct of the business of an underwriter, broker,
    dealer, municipal securities dealer, investment advisor or paid solicitor of purchasers of securities;


 


	 	(l)	He, she or
    it was never subject to a final order of a state or foreign securities commission (or an agency of officer of a state performing
    like functions); a state or foreign authority that supervises or examines banks, savings associations, or credit unions; a state
    or foreign insurance commission (or an agency or officer of a state performing like functions); an appropriate federal or foreign
    banking agency; the CFTC; or the National Credit Union Administration that is based on a violation of any law or regulation that
    prohibits fraudulent, manipulative, or deceptive conduct;


 


	 	(m)	He, she or
    it has never been subject to any order, judgment or decree of any court of competent jurisdiction, that, at the time of the sale
    of the Units, restrained or enjoined him, her or it from engaging or continuing to engage in any conduct or practice: (i) in
    connection with the purchase or sale of any security; (ii) involving the making of any false filing with the SEC or any foreign
    regulatory agency with similar functions; or (iii) arising out of the conduct of the business of an underwriter, broker, dealer,
    municipal securities dealer, investment adviser or paid solicitor of purchasers of securities;


 


	 	(n)	He, she or
    it has never been subject to any order of the SEC or any foreign regulatory agency with similar functions that orders him, her or
    it to cease and desist from committing or causing a future violation of: (i) any scienter-based anti-fraud provision of the
    federal securities laws, including, but not limited to, Section 17(a)(1) of the Securities Act, Section 10(b) of
    the Exchange Act and Rule 10b-5 thereunder, Section 15(c) and Section 206(1) of the Advisers Act or any
    other rule or regulation thereunder; or (ii) Section 5 of the Securities Act;


 


	 	(o)	He, she or
    it has never filed (as a registrant or issuer), or been named as an underwriter in any registration statement or Regulation A offering
    statement filed with the SEC that was the subject of a refusal order, stop order, or order suspending the Regulation A exemption,
    or is, currently, the subject of an investigation or proceeding to determine whether a stop order or suspension order should be issued;


 


	 	(p)	He, she or
    it has never been subject to a United States Postal Service false representation order, or is currently subject to a temporary restraining
    order or preliminary injunction with respect to conduct alleged by the United States Postal Service to constitute a scheme or device
    for obtaining money or property through the mail by means of false representations;


 


	 	(q)	He, she or
    it is not subject to a final order of a state securities commission (or an agency of officer of a state performing like functions);
    a state authority that supervises or examines banks, savings associations, or credit unions; a state insurance commission (or an
    agency or officer of a state performing like functions); an appropriate federal banking agency; the CFTC; or the National Credit
    Union Administration that bars the undersigned from: (i) association with an entity regulated by such commission, authority,
    agency or officer; (ii) engaging in the business of securities, insurance or banking; or (iii) engaging in savings association
    or credit union activities;


 


	 	(r)	He, she or
    it is not subject to an order of the SEC entered pursuant to section 15(b) or 15B(c) of the Securities Exchange Act of
    1934 (the “Exchange Act”) or section 203(e) or 203(f) of the Investment Advisers Act of 1940 (the “Advisers
    Act”) that: (i) suspends or revokes the undersigned’s registration as a broker, dealer, municipal securities dealer
    or investment adviser; (ii) places limitations on the activities, functions or operations of, or imposes civil money penalties
    on, such person; or (iii) bars the undersigned from being associated with any entity or from participating in the offering of
    any penny stock; and


 


	 	(s)	He, she or
    it has never been suspended or expelled from membership in, or suspended or barred from association with a member of, a securities
    self-regulatory organization (e.g., a registered national securities exchange or a registered national or affiliated securities association)
    for any act or omission to act constituting conduct inconsistent with just and equitable principles of trade.


 









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12. The undersigned has full
right and power, without violating any agreement by which he, she or it is bound, to enter into this letter agreement and to serve as
a Director and/or officer of the Company, as applicable.


 


13. The undersigned hereby
waives his, her or its right to exercise redemption rights with respect to any shares of Common Stock owned or to be owned by the undersigned,
directly or indirectly, whether purchased by the undersigned prior to the IPO, in the IPO or in the aftermarket, and agrees that he,
she or it will not seek redemption with respect to or otherwise sell, such shares in connection with any vote to approve a Business Combination
with respect thereto, a vote to amend the provisions of the Company’s Amended and Restated Certificate of Incorporation, or a tender
offer by the Company prior to a Business Combination.


 


14. The undersigned hereby
agrees to not propose, or vote in favor of, an amendment to the Company’s Amended and Restated Certificate of Incorporation with
respect to the Company’s pre-Business Combination activities prior to the consummation of a Business Combination unless the Company
offers holders of IPO Shares the right to receive their pro rata portion of the funds then held in the Trust Fund.


 


15. In connection with Section 5-1401
of the General Obligations Law of the State of New York, this letter agreement shall be governed by, and construed in accordance with,
the laws of the State of New York without regard to principles of conflicts of law that would result in the application of the substantive
law of another jurisdiction. The parties hereto agree that any action, proceeding or claim arising out of or relating in any way to this
letter agreement shall be resolved through final and binding arbitration in accordance with the International Arbitration Rules of
the American Arbitration Association (“AAA”). The arbitration shall be brought before the AAA International Center for Dispute
Resolution’s offices in New York City, New York, will be conducted in English and will be decided by a panel of three arbitrators
selected from the AAA Commercial Disputes Panel and that the arbitrator panel’s decision shall be final and enforceable by any
court having jurisdiction over the party from whom enforcement is sought. The cost of such arbitrators and arbitration services, together
with the prevailing party’s legal fees and expenses, shall be borne by the non-prevailing party or as otherwise directed by the
arbitrators.


 


16. As used herein, (i) a
“Business Combination” shall mean a merger, share exchange, asset acquisition, contractual arrangement,
share purchase, recapitalization, reorganization or other similar business combination with one or more businesses or entities; (ii) “Insiders”
shall mean all officers, directors and shareholders of the Company immediately prior to the IPO; (iii) “Insider Shares”
shall mean all of the shares of Common Stock of the Company acquired by an Insider prior to the IPO and any shares of Common Stock underlying
the Private Units; (iv) “IPO Shares” shall mean the shares of Common Stock issued in the Company’s
IPO; (v) “Private Units” shall mean (x) the Units purchased in the private placement taking place
simultaneously with the consummation of the Company’s IPO and (y) the additional Units that may be purchased in connection
with the exercise of the over-allotment option by the underwriters in the IPO as described in the Registration Statement; (vi) “Registration
Statement” means the registration statement on Form S-1 filed by the Company with respect to the IPO; and (vii) “Trust
Fund” shall mean the trust fund into which a portion of the net proceeds of the Company’s IPO will be deposited.


 


17. 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.


 


If to the Representative:


 


Network 1 Financial Securities, Inc.


2 Bridge Ave #241


Red Bank, NJ 07701


Attn: Karen (Huiyun) Mu


Facsimile: (732) 758-6671





 






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with a copy (which copy shall not constitute
notice) to:


 


Ortoli Rosenstadt
LLP


366 Madison
Ave 3rd floor


New York, NY
10017


Attn: Yarona
L. Yieh


Fax No.: (212)
588-0022


 


If to the Company:


 


Mountain Crest
Acquisition Corp. IV


311 West 43rd
Street, 12 Floor


New York, NY
10036


Attn: Suying
Liu, Chief Executive Officer


 


with a copy (which copy shall not constitute
notice) to:


 


Loeb &
Loeb LLP 


345 Park Avenue


New York, NY
10154


Attn: Giovanni
Caruso, Esq.


Facsimile: (212)
407-4990


 


18. 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
party. Any purported assignment in violation of this paragraph 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 parties hereto and any successors and
assigns thereof.


 


19. The undersigned acknowledges
and understands that the Underwriters and the Company will rely upon the agreements, representations and warranties set forth herein
in proceeding with the IPO.


 


[Signature Page Follows]


 






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	Sincerely,	 


 


	 	

    Mountain Crest Holdings IV LLC
	 	 	 
	 	By:	/s/ Suying Liu
	 	 	Name: Suying
    Liu
	 	 	Title: Chairman,
    Chief Executive Officer and Chief Financial Officer
	 	 	 






	 	DIRECTORS
    AND OFFICERS
	 	 	 
	 	By:	/s/ Suying
    Liu
	 	 	Suying
    Liu
	 	 	 
	 	By:	/s/ Nelson
    Haight
	 	 	Nelson
    Haight
	 	 	 
	 	By:	/s/ Todd
    Milbourn
	 	 	Todd
    Milbourn
	 	 	 
	 	By:	/s/ Wenhua
    Zhang
	 	 	Wenhua
    Zhang


 


[SIGNATURE PAGE TO LETTER AGREEMENT]


 






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