Exhibit 10.3


 


STOCK ESCROW AGREEMENT


 


This STOCK ESCROW AGREEMENT,
dated as of May 17, 2021 (“Agreement”), by and among MOUNTAIN CREST ACQUISITION CORP. III, a Delaware corporation (“Company”),
and the initial shareholders listed on the signature pages hereto (collectively, the “Initial Shareholders”) CONTINENTAL
STOCK TRANSFER & TRUST COMPANY, a New York corporation (“Escrow Agent”).


 


WHEREAS, the Company has entered
into an Underwriting Agreement, dated as of May 17, 2021 (“Underwriting Agreement”), with Chardan Capital Markets LLC
(“Chardan”) acting as representative of the several underwriters (collectively, the “Underwriters”), pursuant
to which, among other matters, the Underwriters have agreed to purchase 5,000,000 units (“Units”) of the Company, plus an
additional 750,000 Units if the Underwriters exercise their over-allotment option in full. Each Unit consists of one share of common
stock of the Company, par value $0.0001 per share (the “Common Stock”) and one right to receive one-tenth (1/10) of a share
of common stock upon the consummation of an initial business combination, all as more fully described in the Company’s final Prospectus,
dated May 10, 2021 (“Prospectus”), comprising part of the Company’s Registration Statement on Form S-1 (File
No. 333-255519) under the Securities Act of 1933, as amended (“Registration Statement”), declared effective on May 17,
2021 (“Effective Date”).


 


WHEREAS, the Initial Shareholders
have agreed as a condition of the sale of the Units to deposit their Insider Shares (as defined in the Prospectus), as set forth opposite
their respective names on Exhibit A attached hereto (collectively “Escrow Shares”), in escrow as hereinafter
provided.


 


WHEREAS, the Company and the
Initial Shareholders desire that the Escrow Agent accept the Escrow Shares, in escrow, to be held and disbursed as hereinafter provided.


 


IT IS AGREED:


 


1. Appointment of
Escrow Agent. The Company and the Initial Shareholders hereby appoint the Escrow Agent to act in accordance with and subject
to the terms of this Agreement and the Escrow Agent hereby accepts such appointment and agrees to act in accordance with and subject to
such terms.


 


2. Deposit of Escrow
Shares. On or prior to the date hereof, each of the Initial Shareholders delivered to the Escrow Agent certificates representing
such Initial Shareholder’s respective Escrow Shares, together with applicable share powers, to be held and disbursed subject to
the terms and conditions of this Agreement. Each of the Initial Shareholders acknowledges that the certificate representing such
Initial Shareholder’s Escrow Shares is legended to reflect the deposit of such Escrow Shares under this Agreement.


 


3. Disbursement of
the Escrow Shares.


 


3.1 The Escrow Agent shall
hold the Escrow Shares during the period (the “Escrow Period”) commencing on the date hereof and (i) for 50% of the Escrow
Shares, ending on the earlier of (x) six months after the date of the consummation of the Company’s initial business combination
(as described in the Registration Statement, hereinafter a “Business Combination”) and (y) the date on which the closing
price of the Common Stock equals or exceeds $12.50 per share (as adjusted for stock splits, stock dividends, reorganizations and recapitalizations)
for any 20 trading days within any 30-trading day period commencing after the Company’s initial Business Combination and (ii) for
the remaining 50% of the Escrow Shares, ending six months after the date of the consummation of an initial Business Combination. The Company
shall promptly provide notice of the consummation of a Business Combination to the Escrow Agent. Upon completion of the Escrow Period,
the Escrow Agent shall disburse such amount of each Initial Shareholder’s Escrow Shares (and any applicable share power) to such
Initial Shareholder; provided, however, that if the Escrow Agent is notified by the Company pursuant to Section 6.7 hereof that the
Company is being liquidated at any time during the Escrow Period, then the Escrow Agent shall promptly destroy the certificates representing
the Escrow Shares; provided further, however, that if, within six months after the Company consummates an initial Business Combination,
the Company (or the surviving entity) subsequently consummates a liquidation, merger, stock exchange or other similar transaction which
results in all of the shareholders of such entity having the right to exchange their shares of Common Stock for cash, securities or other
property, then the Escrow Agent will, upon receipt of a notice executed by the Chairman of the Board, Chief Executive Officer or other
authorized officer of the Company, in form reasonably acceptable to the Escrow Agent, certifying that such transaction is then being consummated
or such conditions have been achieved, as applicable, release the Escrow Shares to the Initial Shareholders. The Escrow Agent shall
have no further duties hereunder after the disbursement or destruction of the Escrow Shares in accordance with this Section 3.1.


 






    


     


    

 


3.2 Notwithstanding Section 3.1,
if the Underwriters do not exercise their over-allotment option to purchase an additional 750,000 Units of the Company in full within
45 days of the date of the Prospectus (as described in the Underwriting Agreement), the Initial Shareholders agree that the Escrow Agent
shall return to the Company for cancellation, at no cost, the number of Escrow Shares held by the Initial Shareholders listed on Exhibit B determined
by multiplying (a) the product of (i) 187,500 multiplied by (ii) a fraction, (x) the numerator of which is the number
of Escrow Shares held by each such holder, and (y) the denominator of which is the total number of Escrow Shares, by (b) a fraction,
(i) the numerator of which is 750,000 minus the number of shares of Common Stock purchased by the Underwriters upon the exercise
of their over-allotment option, and (ii) the denominator of which is 750,000. The Company shall promptly provide notice to the Escrow
Agent of the expiration or termination of the Underwriters’ over-allotment option and the number of Units, if any, purchased by
the Underwriters in connection with their exercise thereof.


 


4. Rights of Initial
Shareholders in Escrow Shares.


 


4.1 Voting Rights as
a Shareholder. Subject to the terms of the Insider Letters described in Section 4.4 hereof and except as herein provided,
the Initial Shareholders shall retain all of their rights as shareholders of the Company during the Escrow Period, including, without
limitation, the right to vote such shares.


 


4.2 Dividends and Other
Distributions in Respect of the Escrow Shares. During the Escrow Period, all dividends payable in cash with respect to the Escrow
Shares shall be paid to the Initial Shareholders, but all dividends payable in stock or other non-cash property (“Non-Cash Dividends”)
shall be delivered to the Escrow Agent to hold in accordance with the terms hereof. As used herein, the term “Escrow Shares”
shall be deemed to include the Non-Cash Dividends distributed thereon, if any.


 


4.3 Restrictions on
Transfer. During the Escrow Period, the only permitted transfers of the Escrow Shares will be (1) to the Company’s
pre-IPO stockholders or their respective affiliates, or to the Company’s offices, directors, advisors and employees, (2) if
the Initial Shareholder is an entity, as a distribution to its, partners, stockholders or members upon its liquidation, (3) by bona
fide gift to a member of the Initial Shareholder’s immediate family or to a trust, the beneficiary of which is the Initial Shareholder
or a member of the Initial Shareholder’s immediate family for estate planning purposes, (4) by virtue of the laws of descent
and distribution upon death of the Initial Shareholder, (5) pursuant to a qualified domestic relations order, (6) by certain
pledges to secure obligations incurred in connection with purchases of the Company’s securities, (7) by private sales at prices
no greater than the price at which the Insider Shares were originally purchased or (8) for the cancellation of up to 187,500 shares
of Common Stock subject to forfeiture to the extent that the Underwriters’ over-allotment is not exercised in full or in part or
in connection with the consummation of our initial Business Combination, in each case (except for clause 8 or with our prior consent)
on the condition that such transfers may be implemented only upon the respective transferee’s written agreement to be bound
by the terms and conditions of this Agreement and of the Insider Letter (as defined below) signed by the Initial Shareholder transferring
the Escrow Shares.


 


4.4 Insider Letters. Each
of the Initial Shareholders has executed a letter agreement with Chardan and the Company, dated as indicated on Exhibit C hereto,
and the form of which is filed as an exhibit to the Registration Statement (“Insider Letter”), respecting the rights and obligations
of such Initial Shareholder in certain events, including but not limited to the liquidation of the Company.


 






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5. Concerning the
Escrow Agent.


 


5.1 Good Faith Reliance. The
Escrow Agent shall not be liable for any action taken or omitted by it in good faith and in the exercise of its own best judgment, and
may rely conclusively and shall be protected in acting upon any order, notice, demand, certificate, opinion or advice of counsel (including
counsel chosen by the Escrow Agent), statement, instrument, report or other paper or document (not only as to its due execution and the
validity and effectiveness of its provisions, but also as to the truth and acceptability of any information therein contained) which is
believed by the Escrow Agent to be genuine and to be signed or presented by the proper person or persons. The Escrow Agent shall
not be bound by any notice or demand, or any waiver, modification, termination or rescission of this Agreement unless evidenced by a writing
delivered to the Escrow Agent signed by the proper party or parties and, if the duties or rights of the Escrow Agent are affected, unless
it shall have given its prior written consent thereto.


 


5.2 Indemnification. The
Escrow Agent shall be indemnified and held harmless by the Company from and against any expenses, including counsel fees and disbursements,
or loss suffered by the Escrow Agent in connection with any action, suit or other proceeding involving any claim which in any way, directly
or indirectly, arises out of or relates to this Agreement, the services of the Escrow Agent hereunder, or the Escrow Shares held by it
hereunder, other than expenses or losses arising from the gross negligence or willful misconduct of the Escrow Agent. Promptly after the
receipt by the Escrow Agent of notice of any demand or claim or the commencement of any action, suit or proceeding, the Escrow Agent shall
notify the other parties hereto in writing. In the event of the receipt of such notice, the Escrow Agent, in its sole discretion, may
commence an action in the nature of interpleader in an appropriate court to determine ownership or disposition of the Escrow Shares or
it may deposit the Escrow Shares with the clerk of any appropriate court or it may retain the Escrow Shares pending receipt of a final,
non-appealable order of a court having jurisdiction over all of the parties hereto directing to whom and under what circumstances the
Escrow Shares are to be disbursed and delivered. The provisions of this Section 5.2 shall survive in the event the Escrow Agent resigns
or is discharged pursuant to Sections 5.5 or 5.6 below.


 


5.3 Compensation. The
Escrow Agent shall be entitled to reasonable compensation from the Company for all services rendered by it hereunder. The Escrow Agent
shall also be entitled to reimbursement from the Company for all expenses paid or incurred by it in the administration of its duties hereunder
including, but not limited to, all counsel, advisors’ and agents’ fees and disbursements and all taxes or other governmental
charges.


 


5.4 Further Assurances. From
time to time on and after the date hereof, the Company and the Initial Shareholders shall deliver or cause to be delivered to the Escrow
Agent such further documents and instruments and shall do or cause to be done such further acts as the Escrow Agent shall reasonably request
to carry out more effectively the provisions and purposes of this Agreement, to evidence compliance herewith or to assure itself that
it is protected in acting hereunder.


 


5.5 Resignation. The
Escrow Agent may resign at any time and be discharged from its duties as escrow agent hereunder by its giving the other parties hereto
written notice and such resignation shall become effective as hereinafter provided. Such resignation shall become effective at such time
that the Escrow Agent shall turn over, to a successor escrow agent appointed by the Company, the Escrow Shares held hereunder. If no new
escrow agent is so appointed within the 60-day period following the giving of such notice of resignation, the Escrow Agent may deposit
the Escrow Shares with any court it reasonably deems appropriate.


 


5.6 Discharge of Escrow
Agent. The Escrow Agent shall resign and be discharged from its duties as escrow agent hereunder if so requested in writing at
any time by the other parties hereto, jointly, provided, however, that such resignation shall become effective only upon acceptance of
appointment by a successor escrow agent as provided in Section 5.5.


 


5.7 Liability. Notwithstanding
anything herein to the contrary, the Escrow Agent shall not be relieved from liability hereunder for its own gross negligence or its own
willful misconduct.


 


5.8 Waiver. The
Escrow Agent hereby waives any right of set-off or any other right, title, interest or claim of any kind (“Claim”) in, or
to any distribution of, the Trust Account (as defined in that certain Investment Management Trust Agreement, dated as of the date hereof,
by and between the Company and the Escrow Agent as trustee thereunder) and hereby agrees not to seek recourse, reimbursement, payment
or satisfaction for any Claim against the Trust Account for any reason whatsoever.


 






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6. Miscellaneous.


 


6.1 Governing Law. This
Agreement shall for all purposes be deemed to be made under and shall be construed 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.


 


6.2 Third Party Beneficiaries. Each
of the Initial Shareholders hereby acknowledges that Chardan is a third-party beneficiary of this Agreement and this Agreement may not
be modified or changed without the prior written consent of Chardan.


 


6.3 Entire Agreement. This
Agreement contains the entire agreement of the parties hereto with respect to the subject matter hereof and, except as expressly provided
herein, may not be changed or modified except by an instrument in writing signed by the party to the charged.


 


6.4 Headings. The
headings contained in this Agreement are for reference purposes only and shall not affect in any way the meaning or interpretation thereof.


 


6.5 Binding Effect. This
Agreement shall be binding upon and inure to the benefit of the respective parties hereto and their legal representatives, successors
and assigns.


 


6.6 Notices. Any
notice or other communication required or which may be given hereunder shall be in writing and either be delivered personally or be mailed,
certified or registered mail, or by private national courier service, return receipt requested, postage prepaid, and shall be deemed given
when so delivered personally or, if mailed, two days after the date of mailing, as follows:


 


	 	If to the Company, to:	Mountain Crest Acquisition Corp. III
	 	 	311 West 43rd Street, 12th Floor
	 	 	New York, NY 10036
	 	 	Attn: Suying Liu, Chief Executive Officer


 


If to a Shareholder, to his address set forth in Exhibit A.


 


	 	and if to the Escrow Agent, to:	Continental Stock Transfer & Trust Company
	 	 	1 State Street
	 	 	New York, New York 10004
	 	 	Attention: Francis Wolf


 


A copy (which copy shall not constitute notice)
sent hereunder shall be sent to:


 


	 	 	Chardan Capital Markets LLC
	 	 	17 State Street, 21st Floor
	 	 	New York, NY 10004
	 	 	Attn: Jack Liu
	 	 	Fax: (646) 465-9039


 


	 	and:	Reed Smith LLP
	 	 	599 Lexington Avenue
	 	 	New York, New York 10022
	 	 	Attn: Ari Edelman
	 	 	Fax: (212) 521-5450


 


	 	and:	Loeb & Loeb LLP
	 	 	345 Park Avenue
	 	 	New York, New York 10154
	 	 	Attn: Mitchell S. Nussbaum, Esq. and Giovanni Caruso, Esq.
	 	 	Fax: (212) 407-4990


 






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	 	and:	Continental Stock Transfer & Trust Company
	 	 	1 State Street
	 	 	New York, New York 10004
	 	 	Attention: Francis Wolf


 


The parties may change the
persons and addresses to which the notices or other communications are to be sent by giving written notice to any such change in the manner
provided herein for giving notice.


 


6.7 Liquidation of the
Company. The Company shall give the Escrow Agent written notification of the liquidation and dissolution of the Company in the
event that the Company fails to consummate a Business Combination within the time period specified in the Prospectus.


 


[Signature Page Follows]






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WITNESS the execution of this
Agreement as of the date first above written.


 


	 	COMPANY:
	 	 
	 	MOUNTAIN CREST ACQUISITION CORP. III
	 	 	 
	 	By:	/s/ Suying Liu
	 	 	Name: 	Suying Liu
	 	 	Title:	Chief Executive Officer


 


	 	
    INITIAL SHAREHOLDERS:

     

    MOUNTAIN CREST HOLDINGS III LLC

	 	 
	 	 	/s/ Suying Liu
	 	 	Name: 	Suying Liu                 
	 	 	Title:	Member


 


	 	 	/s/ Nelson Haight
	 	 	Name: 	Nelson Haight        


 


	 	 	/s/ Todd Milbourn
	 	 	Name: 	Todd Milbourn


 


	 	 	/s/ Wenhua Zhang
	 	 	Name: 	Wenhua Zhang


 


	 	
    ESCROW AGENT:

     

    CONTINENTAL STOCK TRANSFER & TRUST COMPANY

	 	 
	 	By:	/s/ Francis Wolf
	 	 	Name: 	Francis E. Wolf, Jr.          
	 	 	Title:	Vice President


 


[Signature Page to Stock
Escrow Agreement]






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EXHIBIT A


 


Initial Shareholders


 


	Name of Initial Shareholder	 	Number of Shares	 	Date of Insider Letter
	Mountain Crest Holdings III LLC	 	 1,431,500	 	May 17, 2021
	 Nelson Haight	 	 2,000	 	May 17, 2021
	 Todd Milbourn	 	 2,000	 	May 17, 2021
	 Wenhua Zhang	 	 2,000	 	May 17, 2021


 






    A-1


     


    

 





EXHIBIT B


 


Escrow Shares


 






    B-1


     


    




 


EXHIBIT C


 


Insider Letter


 






    C-1