Exhibit 10.1


 


EXECUTION VERSION 


 


THIS PROMISSORY NOTE (THIS “NOTE”) HAS NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”). THIS NOTE HAS BEEN ACQUIRED
FOR INVESTMENT ONLY AND MAY NOT BE SOLD, TRANSFERRED OR ASSIGNED IN THE ABSENCE OF REGISTRATION OF THE RESALE THEREOF UNDER THE
SECURITIES ACT OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY IN FORM, SCOPE AND SUBSTANCE TO THE COMPANY THAT SUCH REGISTRATION
IS NOT REQUIRED.


 


PROMISSORY NOTE


 


	Principal Amount: Up to US$300,000	 	Dated as of February 18, 2021




 


FOR VALUE RECEIVED and subject to the terms
and conditions set forth herein, FirstMark Acquisition Corp. III, a Cayman Islands exempted company (“Maker”),
promises to pay to the order of FirstMark Sponsor III LLC, a Delaware limited liability company, or its registered assigns or successors
in interest (collectively, “Payee”), or order, the principal sum of Three Hundred Thousand U.S. Dollars (US$300,000)
or such lesser amount as shall have been advanced by Payee to Maker and shall remain unpaid under this Note on the Maturity Date
(as defined below) in lawful money of the United States of America, on the terms and conditions described below. All payments on
this Note shall be made by check or wire transfer of immediately available funds or as otherwise determined by Maker to such account
as Payee may from time to time designate by written notice in accordance with the provisions of this Note.


 


1.            Principal. The entire unpaid principal balance of this Note shall be due and payable in full on the earlier of: (i) December
31, 2021, and (ii) the date on which Maker consummates an initial public offering of its securities (such earlier date of (i) and
(ii), the “Maturity Date”), unless accelerated upon the occurrence of an Event of Default (as defined below).
The principal balance may be prepaid at any time by Maker, at its election and without penalty. Under no circumstances shall any
individual, including but not limited to any officer, director, employee or shareholder of Maker, be obligated personally for any
obligations or liabilities of Maker hereunder.


 


2.            Drawdown
Requests. Maker and Payee agree that Maker may request, from time to time, up to Three Hundred Thousand U.S. Dollars (US$300,000)
in draw downs under this Note to be used for costs and expenses related to Maker’s proposed initial public offering of its
securities (the “IPO”), including its formation. The principal of this Note may be drawn down from time to
time prior to the Maturity Date upon request from Maker to Payee (each, a “Drawdown Request”). Each Drawdown
Request must state the amount to be drawn down, and must not be an amount less than Ten Thousand U.S. Dollars (US$10,000) unless
agreed upon by Maker and Payee. Payee shall fund each Drawdown Request no later than five (5) business days after receipt of a
Drawdown Request; provided, however, that the maximum amount of drawdowns outstanding under this Note at any time
may not exceed Three Hundred Thousand U.S. Dollars (US$300,000). No fees, payments or other amounts shall be due to Payee in connection
with, or as a result of, any Drawdown Request by Maker.


 


3.            Interest. No interest shall accrue on the unpaid principal balance of this Note.


 


4.            Application
of Payments. All payments shall be applied first to payment in full of any costs incurred in the collection of any sum due
under this Note, including (without limitation) reasonable attorney’s fees, then to the payment in full of any late charges
and finally to the reduction of the unpaid principal balance of this Note.


 


5.            Events of Default. The following shall constitute an event of default (“Event of Default”):


 






     


     


    

 


(a)               
Failure to Make Required Payments. Failure by Maker to pay the principal amount due pursuant to this Note on the
Maturity Date.


 


(b)               
Voluntary Bankruptcy, Etc. The commencement by Maker of a voluntary case under any applicable bankruptcy, insolvency,
reorganization, rehabilitation or other similar law, or the consent by it to the appointment of or taking possession by a receiver,
liquidator, assignee, trustee, custodian, sequestrator (or other similar official) of Maker or for any substantial part of its
property, or the making by it of any assignment for the benefit of creditors, or the failure of Maker generally to pay its debts
as such debts become due, or the taking of corporate action by Maker in furtherance of any of the foregoing.


 


(c)               
Involuntary Bankruptcy, Etc. The entry of a decree or order for relief by a court having jurisdiction in the premises
in respect of Maker in an involuntary case under any applicable bankruptcy, insolvency or other similar law, or appointing a receiver,
liquidator, assignee, custodian, trustee, sequestrator (or similar official) of Maker or for any substantial part of its property,
or ordering the winding-up or liquidation of its affairs, and the continuance of any such decree or order unstayed and in effect
for a period of sixty (60) consecutive days.


 


6.            Remedies.


 


(a)               
Upon the occurrence of an Event of Default specified in Section 5(a) hereof, Payee may, by written notice to Maker, declare
this Note to be due immediately and payable, whereupon the unpaid principal amount of this Note, and all other amounts payable
thereunder, shall become immediately due and payable without presentment, demand, protest or other notice of any kind, all of which
are hereby expressly waived, anything contained herein or in the documents evidencing the same to the contrary notwithstanding.


 


(b)               
Upon the occurrence of an Event of Default specified in Sections 5(b) or 5(c), the unpaid principal balance of this Note,
and all other sums payable with regard to this Note, shall automatically and immediately become due and payable, in all cases without
any action on the part of Payee.


 


7.             Waivers. Maker and all endorsers and guarantors of, and sureties for, this Note waive presentment for payment, demand,
notice of dishonor, protest, and notice of protest with regard to the Note, all errors, defects and imperfections in any proceedings
instituted by Payee under the terms of this Note, and all benefits that might accrue to Maker by virtue of any present or future
laws exempting any property, real or personal, or any part of the proceeds arising from any sale of any such property, from attachment,
levy or sale under execution, or providing for any stay of execution, exemption from civil process, or extension of time for payment;
and Maker agrees that any real estate that may be levied upon pursuant to a judgment obtained by virtue hereof, on any writ of
execution issued hereon, may be sold upon any such writ in whole or in part in any order desired by Payee.


 


8.            Unconditional
Liability. Maker hereby waives all notices in connection with the delivery, acceptance, performance, default, or enforcement
of the payment of this Note, and agrees that its liability shall be unconditional, without regard to the liability of any other
party, and shall not be affected in any manner by any indulgence, extension of time, renewal, waiver or modification granted or
consented to by Payee, and consents to any and all extensions of time, renewals, waivers, or modifications that may be granted
by Payee with respect to the payment or other provisions of this Note, and agrees that additional makers, endorsers, guarantors,
or sureties may become parties hereto without notice to Maker or affecting Maker’s liability hereunder.


 






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9.            Notices.
All notices, statements or other documents which are required or contemplated by this Note shall be: (i) in writing and delivered
personally or sent by first class registered or certified mail, overnight courier service or facsimile or electronic transmission
to the address designated in writing, (ii) by facsimile to the number most recently provided to such party or such other
address or fax number as may be designated in writing by such party or (iii) by electronic mail, to the electronic mail address
most recently provided to such party or such other electronic mail address as may be designated in writing by such party. Any
notice or other communication so transmitted shall be deemed to have been given on the day of delivery, if delivered personally,
on the business day following receipt of written confirmation, if sent by facsimile or electronic transmission, one (1) business
day after delivery to an overnight courier service or five (5) days after mailing if sent by mail.


 


10.        
Construction. THIS NOTE SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH THE LAWS OF NEW YORK.


 


11.        
Severability. Any provision contained in this Note which is prohibited or unenforceable in any jurisdiction shall, as
to such jurisdiction, be ineffective to the extent of such prohibition or unenforceability without invalidating the remaining provisions
hereof, and any such prohibition or unenforceability in any jurisdiction shall not invalidate or render unenforceable such provision
in any other jurisdiction.


 


12.         
Trust Waiver. Notwithstanding anything herein to the contrary, Payee hereby waives any and all right, title, interest
or claim of any kind (“Claim”) in or to any distribution of or from the trust account to be established in which
proceeds of the IPO (including the deferred underwriting discounts and commissions) and proceeds of the sale of the warrants issued
in a private placement to occur in connection with the consummation of the IPO are to be deposited, as described in greater detail
in the registration statement and prospectus to be filed with the Securities and Exchange Commission in connection with the IPO,
and hereby agrees not to seek recourse, reimbursement, payment or satisfaction for any Claim against the trust account for any
reason whatsoever.


 


13.          Amendment;
Waiver. Any amendment hereto or waiver of any provision hereof may be made with, and only with, the written consent of Maker
and Payee.


 


14.         
Assignment. No assignment or transfer of this Note or any rights or obligations hereunder may be made by any party hereto
(by operation of law or otherwise) without the prior written consent of the other party hereto and any attempted assignment without
the required consent shall be void.


 


[Signature page follows]


 






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IN WITNESS WHEREOF, Maker, intending
to be legally bound hereby, has caused this Note to be duly executed by the undersigned as of the day and year first above written.


 


		FIRSTMARK ACQUISITION CORP. III
	 	 	 
	 	By:	/s/ Eric Cheung
	 	 	Name: Eric Cheung
	 	 	Title:   Secretary



 




 




	Agreed and Acknowledged:	 
	 	 	 
	FIRSTMARK SPONSOR III LLC	 
	 	 	 
	By:	/s/ Richard Heitzmann	 
	 	Richard Heitzmann	 
	 	Sole Member	 



 


[Signature Page to Promissory Note]