Exhibit 10.2


 


EXECUTION
VERSION


 


INVESTMENT
MANAGEMENT TRUST AGREEMENT


 


This
Investment Management Trust Agreement (this “Agreement”) is made effective as of October 5, 2020, by
and between FirstMark Horizon Acquisition Corp., a Delaware corporation (the “Company”), and Continental
Stock Transfer & Trust Company, a New York corporation (the “Trustee”).


 


WHEREAS,
the Company’s registration statement on Form S-1, File No. 333-248916 (the “Registration Statement”),
and prospectus (the “Prospectus”) for the initial public offering of the Company’s units (the
“Units”), each of which consists of one share of the Company’s Class A common stock, par value
$0.0001 per share (“Common Stock”), and one-third of one redeemable warrant, each whole warrant entitling
the holder thereof to purchase one share of Common Stock (such initial public offering hereinafter referred to as the “Offering”),
has been declared effective as of the date hereof by the U.S. Securities and Exchange Commission; and


 


WHEREAS,
the Company has entered into an Underwriting Agreement (the “Underwriting Agreement”) with Credit Suisse
Securities (USA) LLC, as representative (the “Representative”) of the several underwriters (the “Underwriters”)
named therein; and


 


WHEREAS,
as described in the Prospectus, $360,000,000 of the gross proceeds of the Offering and sale of the Private Placement Warrants
(as defined in the Underwriting Agreement) (or $414,000,000 if the Underwriters’ over-allotment option is exercised in full)
will be delivered to the Trustee to be deposited and held in a segregated trust account located at all times in the United States
(the “Trust Account”) for the benefit of the Company and the holders of the shares of Common Stock included
in the Units issued in the Offering as hereinafter provided (the amount to be delivered to the Trustee (and any interest subsequently
earned thereon) is referred to herein as the “Property,” the stockholders for whose benefit the Trustee
shall hold the Property will be referred to as the “Public Stockholders,” and the Public Stockholders
and the Company will be referred to together as the “Beneficiaries”); and


 


WHEREAS,
pursuant to the Underwriting Agreement, a portion of the Property equal to $12,600,000, or $14,490,000 if the Underwriters’
over-allotment option is exercised in full, is attributable to deferred underwriting discounts and commissions that may be payable
by the Company to the Underwriters upon the consummation of the Business Combination (as defined below) (the “Deferred
Discount”); and


 


WHEREAS,
the Company and the Trustee desire to enter into this Agreement to set forth the terms and conditions pursuant to which the Trustee
shall hold the Property.


 


NOW
THEREFORE, IT IS AGREED:


 


1. Agreements
and Covenants of Trustee. The Trustee hereby agrees and covenants to:


 


(a) Hold
the Property in trust for the Beneficiaries in accordance with the terms of this Agreement in the Trust Account established by
the Trustee located in the United States at J.P. Morgan Chase Bank, N.A. (or at another U.S. chartered commercial bank with consolidated
assets of $100 billion or more) and at a brokerage institution selected by the Trustee that is reasonably satisfactory to the
Company;


 






     


     


    




 


(b) Manage,
supervise and administer the Trust Account subject to the terms and conditions set forth herein;


 


(c) In
a timely manner, upon the written instruction of the Company, invest and reinvest the Property in United States government securities
within the meaning of Section 2(a)(16) of the Investment Company Act of 1940, as amended, having a maturity of 185 days or less,
or in money market funds meeting the conditions of paragraphs (d)(1), (d)(2), (d)(3) and (d)(4) of Rule 2a-7 promulgated under
the Investment Company Act of 1940, as amended (or any successor rule), which invest only in direct U.S. government treasury obligations,
as determined by the Company; the Trustee may not invest in any other securities or assets, it being understood that the Trust
Account will earn no interest while account funds are uninvested awaiting the Company’s instructions hereunder; while on
deposit, the Trustee may earn bank credits or other consideration;


 


(d) Collect
and receive, when due, all interest or other income arising from the Property, which shall become part of the “Property,”
as such term is used herein;


 


(e) Promptly
notify the Company and the Representative of all communications received by the Trustee with respect to any Property requiring
action by the Company;


 


(f) Supply
any necessary information or documents as may be requested by the Company (or its authorized agents) in connection with the Company’s
preparation of tax returns relating to assets held in the Trust Account or in connection with the preparation or completion of
the audit of the Company’s financial statements by the Company’s auditors;


 


(g) Participate
in any plan or proceeding for protecting or enforcing any right or interest arising from the Property if, as and when instructed
by the Company to do so;


 


(h) Render
to the Company monthly written statements of the activities of, and amounts in, the Trust Account reflecting all receipts and
disbursements of the Trust Account;


 


(i) Commence
liquidation of the Trust Account only after and promptly following (x) receipt of, and only in accordance with the terms
of, a letter from the Company (“Termination Letter”) in a form substantially similar to that attached
hereto as either Exhibit A or Exhibit B, as applicable, signed on behalf of the Company by its Chief Executive Officer,
President, Chief Financial Officer, Secretary or other authorized officer of the Company (an “Authorized Representative”),
and complete the liquidation of the Trust Account and distribute the Property in the Trust Account, including interest (which
interest shall be net of any taxes payable, and less up to $100,000 of interest that may be released to the Company to pay dissolution
expenses), only as directed in the Termination Letter and other documents referred to therein, or (y) upon the date which
is the later of (1) 24 months after the closing of the Offering and (2) such later date as may be approved by the Company’s
stockholders in accordance with the Company’s amended and restated certificate of incorporation, as amended from time to
time, if a Termination Letter has not been received by the Trustee prior to such date, in which case the Trust Account shall be
liquidated in accordance with the procedures set forth in the Termination Letter attached as Exhibit B and the Property
in the Trust Account, including interest (which interest shall be net of any taxes payable, and less up to $100,000 of interest
that may be released to the Company to pay dissolution expenses) shall be distributed to the Public Stockholders of record as
of such date;


 






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(j) Upon
written request from the Company, which may be given from time to time in a form substantially similar to that attached hereto
as Exhibit C (a “Tax Payment Withdrawal Instruction”), withdraw from the Trust Account and distribute
on behalf of the Company the amount of interest earned on the Property requested by the Company to cover any tax obligation owed
by the Company as a result of assets of the Company or interest or other income earned on the Property, which amount shall be
delivered directly to the Company by electronic funds transfer or other method of prompt payment, and the Company shall forward
such payment to the relevant taxing authority; provided, however, that to the extent there is not sufficient cash
in the Trust Account to pay such tax obligation, the Trustee shall liquidate such assets held in the Trust Account as shall be
designated by the Company in writing to make such distribution so long as there is no reduction in the principal amount initially
deposited in the Trust Account; provided, further, however, that if the tax to be paid is a franchise tax,
the written request by the Company to make such distribution shall be accompanied by a copy of the franchise tax bill for the
Company and a written statement from the principal financial officer of the Company setting forth the actual amount payable (it
being acknowledged and agreed that any such amount in excess of interest income earned on the Property shall not be payable from
the Trust Account). The written request of the Company referenced above shall constitute presumptive evidence that the Company
is entitled to said funds, and the Trustee shall have no responsibility to look beyond said request;


 


(k) Upon
written request from the Company, which may be given from time to time in a form substantially similar to that attached hereto
as Exhibit D (a “Stockholder Redemption Withdrawal Instruction”), the Trustee shall distribute
to or on behalf of the Company the amount requested by the Company to be used to redeem shares of Common Stock from Public Stockholders
properly submitted in connection with a stockholder vote to approve an amendment to the Company’s amended and restated certificate
of incorporation (A) to modify the substance or timing of the Company’s obligation to allow redemptions in connection with
its initial Business Combination or to redeem 100% of the Company’s public shares of Common Stock if the Company does not
complete its initial Business Combination within the time period set forth therein or (B) with respect to any other provision
relating to the Company’s stockholders’ rights or pre-initial Business Combination activity. The written request of
the Company referenced above shall constitute presumptive evidence that the Company is entitled to distribute said funds, and
the Trustee shall have no responsibility to look beyond said request; and


 


(l) Not
make any withdrawals or distributions from the Trust Account other than pursuant to Section 1(i), (j) or (k) above.


 


2. Agreements
and Covenants of the Company. The Company hereby agrees and covenants to:


 


(a) Give
all instructions to the Trustee hereunder in writing, signed by an Authorized Representative of the Company. In addition, except
with respect to its duties under Sections 1(i), 1(j) and 1(k) hereof, the Trustee shall be entitled to rely
on, and shall be protected in relying on, any verbal or telephonic advice or instruction which it, in good faith and with reasonable
care, believes to be given by any one of the persons authorized above to give written instructions, provided that the Company
shall promptly confirm such instructions in writing;


 






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(b) Subject
to Section 4 hereof, hold the Trustee harmless and indemnify the Trustee from and against any and all reasonable and documented
out-of-pocket expenses, including reasonable outside counsel fees and disbursements, or losses suffered by the Trustee in connection
with any action taken by it hereunder and in connection with any action, suit or other proceeding brought against the Trustee
involving any claim, or in connection with any claim or demand, which in any way arises out of or relates to this Agreement, the
services of the Trustee hereunder, or the Property or any interest earned on the Property, except for expenses and losses resulting
from the Trustee’s gross negligence, fraud or willful misconduct. Promptly after the receipt by the Trustee of notice of
demand or claim or the commencement of any action, suit or proceeding, pursuant to which the Trustee intends to seek indemnification
under this Section 2(b), it shall notify the Company in writing of such claim (hereinafter referred to as the “Indemnified
Claim”). The Trustee shall have the right to conduct and manage the defense against such Indemnified Claim; provided
that the Trustee shall obtain the consent of the Company with respect to the selection of counsel, which consent shall not be
unreasonably withheld. The Trustee may not agree to settle any Indemnified Claim without the prior written consent of the Company,
which such consent shall not be unreasonably withheld. The Company may participate in such action with its own counsel;


 


(c) Pay
the Trustee the fees set forth on Schedule A hereto, including an initial acceptance fee, annual administration fee, and
transaction processing fee, which fees shall be subject to modification by the parties from time to time. It is expressly understood
that the Property shall not be used to pay such fees unless and until it is distributed to the Company pursuant to Sections
1(i) through 1(j) hereof. The Company shall pay the Trustee the initial acceptance fee and the first annual administration
fee at the consummation of the Offering. The Company shall not be responsible for any other fees or charges of the Trustee except
as set forth in this Section 2(c) and as may be provided in Section 2(b) hereof;


 


(d) In
connection with any vote of the Company’s stockholders regarding any merger, capital stock exchange, asset acquisition,
stock purchase, reorganization or other similar business combination involving the Company and one or more businesses (a “Business
Combination”), provide to the Trustee an affidavit or certificate of the inspector of elections for the stockholder
meeting verifying the vote of such stockholders regarding such Business Combination;


 


(e) Provide
the Representative with a copy of any Termination Letter(s) and/or any other correspondence that is sent to the Trustee with respect
to any proposed withdrawal from the Trust Account promptly after it issues the same;


 


(f) Expressly
provide in any Instruction Letter (as defined in Exhibit A) delivered in connection with a Termination Letter in the Form
of Exhibit A that the Deferred Discount be paid directly to the account or accounts directed by the Representative; and


 






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(g) Instruct
the Trustee to make only those distributions that are permitted under this Agreement, and refrain from instructing the Trustee
to make any distributions that are not permitted under this Agreement.


 


3. Limitations
of Liability. The Trustee shall have no responsibility or liability to:


 


(a) Imply
obligations, perform duties, inquire or otherwise be subject to the provisions of any agreement or document other than this Agreement
and that which is expressly set forth herein;


 


(b) Take
any action with respect to the Property, other than as directed in Section 1 hereof, and the Trustee shall have no liability to
any party except for liability arising out of the Trustee’s gross negligence, fraud or willful misconduct;


 


(c) Institute
any proceeding for the collection of any principal and income arising from, or institute, appear in or defend any proceeding of
any kind with respect to, any of the Property unless and until it shall have received instructions from the Company given as provided
herein to do so and the Company shall have advanced or guaranteed to it funds sufficient to pay any expenses incident thereto;


 


(d) Refund
any depreciation in principal of any Property;


 


(e) Assume
that the authority of any person designated by the Company to give instructions hereunder shall not be continuing unless provided
otherwise in such designation, or unless the Company shall have delivered a written revocation of such authority to the Trustee;


 


(f) The
other parties hereto or to anyone else for any action taken or omitted by it, or any action suffered by it to be taken or omitted,
in good faith and in the Trustee’s best judgment, except for the Trustee’s gross negligence, fraud or willful misconduct.
The Trustee may rely conclusively and shall be protected in acting upon any written direction, order, notice, demand, certificate,
opinion or advice of counsel (including counsel chosen by the Trustee with written notification to the Company, which counsel
may be the Company’s counsel), 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 the Trustee believes, in good faith and with reasonable care, to be genuine and to be signed or presented by the proper
person or persons. The Trustee shall not be bound by any notice or demand, or any waiver, modification, termination or rescission
of this Agreement or any of the terms hereof, unless evidenced by a written instrument delivered to the Trustee, signed by the
proper party or parties and, if the duties or rights of the Trustee are affected, unless it shall give its prior written consent
thereto;


 


(g) Verify
the accuracy of the information contained in the Registration Statement;


 


(h) Provide
any assurance that any Business Combination entered into by the Company or any other action taken by the Company is as contemplated
by the Registration Statement;


 






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(i) File
information returns with respect to the Trust Account with any local, state or federal taxing authority or provide periodic written
statements to the Company documenting the taxes payable by the Company, if any, relating to any interest income earned on the
Property;


 


(j) Prepare,
execute and file tax reports, income or other tax returns and pay any taxes with respect to any income generated by, and activities
relating to, the Trust Account, regardless of whether such tax is payable by the Trust Account or the Company, including, but
not limited to, franchise and income tax obligations, except pursuant to Section 1(j) hereof; or


 


(k) Verify
calculations, qualify or otherwise approve the Company’s written requests for distributions pursuant to Sections 1(i),
1(j) or 1(k) hereof.


 


4. Trust
Account Waiver. The Trustee has no right of set-off or any right, title, interest or claim of any kind (“Claim”)
to, or to any monies in, the Trust Account, and hereby irrevocably waives any Claim to, or to any monies in, the Trust Account
that it may have now or in the future. In the event the Trustee has any Claim against the Company under this Agreement, including,
without limitation, under Section 2(b) or Section 2(c) hereof, the Trustee shall pursue such Claim solely against
the Company and its assets outside the Trust Account and not against the Property or any monies in the Trust Account.


 


5. Termination.
This Agreement shall terminate as follows:


 


(a) If
the Trustee gives written notice to the Company that it desires to resign under this Agreement, the Company shall use its reasonable
efforts to locate a successor trustee, pending which the Trustee shall continue to act in accordance with this Agreement. At such
time that the Company notifies the Trustee that a successor trustee has been appointed and has agreed to become subject to the
terms of this Agreement (whether following the Trustee giving notice that it desires to resign under this Agreement or the Company
otherwise electing to replace the Trustee under this Agreement), the Trustee shall transfer the management of the Trust Account
to the successor trustee, including but not limited to the transfer of copies of the reports and statements relating to the Trust
Account, whereupon this Agreement shall terminate; provided, however, that in the event that the Company does not
locate a successor trustee within ninety (90) days of receipt of the resignation notice from the Trustee, the Trustee may submit
an application to have the Property deposited with any court in the State of New York or with the United States District Court
for the Southern District of New York and upon such deposit, the Trustee shall be immune from any liability whatsoever;


 


(b) At
such time that the Trustee has completed the liquidation of the Trust Account and its obligations in accordance with the provisions
of Section 1(i) hereof and distributed the Property in accordance with the provisions of the Termination Letter, this Agreement
shall terminate except with respect to Section 2(b); or


 


(c) If
the Offering is not consummated within ten (10) business days of the date of this Agreement, in which case any funds received
by the Trustee from the Company or FirstMark Horizon Sponsor LLC, as applicable, shall be returned promptly following the receipt
by the Trustee of written instructions from the Company.


 






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6. Miscellaneous.


 


(a) The
Company and the Trustee each acknowledge that the Trustee will follow the security procedures set forth herein with respect to
funds transferred from the Trust Account. The Company and the Trustee will each restrict access to confidential information relating
to such security procedures to authorized persons. Each party must notify the other party immediately if it has reason to believe
unauthorized persons may have obtained access to such confidential information, or of any change in its authorized personnel.
In executing funds transfers, the Trustee shall rely upon all information supplied to it by the Company, including, account names,
account numbers, and all other identifying information relating to a Beneficiary, Beneficiary’s bank or intermediary bank.
Except for any liability arising out of the Trustee’s gross negligence, fraud or willful misconduct, the Trustee shall not
be liable for any loss, liability or out-of-pocket expense resulting from any error in the information or transmission of the
funds.


 


(b) This
Agreement shall be governed by and construed and enforced in accordance with the laws of the State of New York.


 


(c) This
Agreement contains the entire agreement and understanding of the parties hereto with respect to the subject matter hereof. Except
for Section 1(i), 1(j) or 1(k) (which sections may not be modified, amended or deleted without the affirmative
vote of sixty-five percent (65%) of the then outstanding shares of Common Stock and Class B common stock, par value $0.0001 per
share, of the Company voting together as a single class; provided that no such amendment will affect any Public Stockholder who
has otherwise validly indicated his, her or its election to redeem his, her or its shares of Common Stock in connection with a
stockholder vote sought to amend this Agreement), this Agreement or any provision hereof may only be changed, amended or modified
(other than to correct a typographical error) by a writing signed by each of the parties hereto.


 


(d) The
parties hereto consent to the jurisdiction and venue of any state or federal court located in the City of New York, State of New
York, for purposes of resolving any disputes hereunder. AS TO ANY CLAIM, CROSS-CLAIM OR COUNTERCLAIM IN ANY WAY RELATING TO
THIS AGREEMENT, EACH PARTY WAIVES THE RIGHT TO TRIAL BY JURY.


 


(e) Any
notice, consent or request to be given in connection with any of the terms or provisions of this 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 by electronic mail:


 


if
to the Trustee, to:


 


Continental
Stock Transfer & Trust Company


1
State Street, 30th Floor


New
York, New York 10004


Attn:
Francis Wolf & Celeste Gonzalez


Email:
fwolf@continentalstock.com;


cgonzalez@continentalstock.com


 






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if
to the Company, to:


 


FirstMark
Horizon Acquisition Corp.


100
5th Ave, 3rd Floor


New
York, NY 10011


Attn:
Eric D. Cheung


Email:
eric@firstmarkcap.com


 


in
each case, with copies to:


 


FirstMark
Horizon Sponsor LLC


100
5th Ave, 3rd Floor


New
York, NY 10011


Attn:
Eric D. Cheung


Email:
eric@firstmarkcap.com


 


and


 


Skadden,
Arps, Slate, Meagher & Flom LLP


525
University Ave., Suite 1400


Palo
Alto, CA 94301


Attn:
Gregg A. Noel and Michael J. Mies


 


and


 


Credit
Suisse Securities (USA) LLC


Eleven
Madison Avenue


New
York, N.Y. 10010-3629


Attn:
Head of Equity Capital Markets, with a copy to the General Counsel Investment Banking


 


and


 


Proskauer
Rose LLP


Eleven
Times Square


New
York, NY 10036-8299


Attn:
David A. Curtiss, Esq.


 


(f) This
Agreement may not be assigned by the Trustee without the prior consent of the Company.


 


(g) Each
of the Company and the Trustee hereby represents that it has the full right and power and has been duly authorized to enter into
this Agreement and to perform its respective obligations as contemplated hereunder. The Trustee acknowledges and agrees that it
shall not make any claims or proceed against the Trust Account, including by way of set-off, and shall not be entitled to any
funds in the Trust Account under any circumstance.


 






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(h) This
Agreement is the joint product of the Trustee and the Company and each provision hereof has been subject to the mutual consultation,
negotiation and agreement of such parties and shall not be construed for or against any party hereto.


 


(i) This
Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all such counterparts
shall together constitute one and the same instrument. Delivery of a signed counterpart of this Agreement by facsimile or electronic
transmission shall constitute valid and sufficient delivery thereof.


 


(j) Each
of the Company and the Trustee hereby acknowledges and agrees that the Representative, on behalf of the Underwriters, is a third
party beneficiary of this Agreement.


 


(k) Except
as specified herein, no party to this Agreement may assign its rights or delegate its obligations hereunder to any other person
or entity.


 


[Signature
page follows]


 




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IN
WITNESS WHEREOF, the parties have duly executed this Investment Management Trust Agreement as of the date first written above.


 





	 	FirstMark Horizon Acquisition Corp.
	 	 	 
	 	By:	/s/ Eric D. Cheung
	 	Name:	Eric D. Cheung
	 	Title:	Secretary
	 	 	 
	 	TRUSTEE:	 
	 	 	 
	 	Continental Stock Transfer & Trust Company,
	 	as Trustee	 
	 	 	 
	 	By:	/s/ Francis Wolf
	 	Name:	Francis Wolf
	 	Title:	Vice President








 




     


     


    

 


SCHEDULE
A


 


	 
Fee Item
	 	Time and method of payment	 	Amount	 
	Initial acceptance fee	 	Initial closing of the Offering by wire transfer.	 	$	3,500.00	 
	Annual fee	 	First year fee payable at initial closing of the Offering by wire transfer, thereafter on the anniversary of the effective date of the Offering by wire transfer or check.	 	$	10,000.00	 
	Transaction processing fee for disbursements to Company under Sections 1(i) and 1(j)	 	Billed to Company following disbursement made to Company under Sections 1(i) and 1(j)	 	$	250.00	 
	Paying Agent services as required pursuant to Section 1(i) and 1(k)	 	Billed to Company upon delivery of service pursuant to Section 1(i) and 1(k)	 	 	Prevailing rates	 



 


 




     


     


    

 


EXHIBIT
A


 


[Letterhead
of Company]


 


[Insert
date]


 


Continental
Stock Transfer & Trust Company


One
State Street, 30th Floor


New
York, New York 10004


Attn:
Francis Wolf & Celeste Gonzalez


 


Re:Trust
Account – Termination Letter


 


Dear
Mr. Wolf and Ms. Gonzalez:


 


Pursuant
to Section 1(i) of the Investment Management Trust Agreement between FirstMark Horizon Acquisition Corp. (the “Company”)
and Continental Stock Transfer & Trust Company (the “Trustee”), dated as of [●], 2020 (the
“Trust Agreement”), this is to advise you that the Company has entered into an agreement with___________________
(the “Target Business”) to consummate a business combination with the Target Business (the “Business
Combination”) on or about [insert date]. The Company shall notify you at least seventy-two (72) hours in advance
of the actual date (or such shorter time period as you may agree) of the consummation of the Business Combination (the “Consummation
Date”). Capitalized terms used but not defined herein shall have the meanings set forth in the Trust Agreement.


 


In
accordance with the terms of the Trust Agreement, we hereby authorize you to commence to liquidate all of the assets of the Trust
Account and to transfer the proceeds into the above-referenced trust operating account at J.P. Morgan Chase Bank, N.A. to the
effect that, on the Consummation Date, all of the funds held in the Trust Account will be immediately available for transfer to
the account or accounts that the Representative (with respect to the Deferred Discount) and the Company shall direct on the Consummation
Date. It is acknowledged and agreed that while the funds are on deposit in the trust operating account at J.P. Morgan Chase Bank,
N.A. awaiting distribution, neither the Company nor the Representative will earn any interest or dividends.


 






     


     


    




 


On the Consummation
Date (i) counsel for the Company shall deliver to you written notification that the Business Combination has been consummated,
or will be consummated substantially, concurrently with your transfer of funds to the accounts as directed by the Company (the
“Notification”) and (ii) the Company shall deliver to you (a) a certificate by the Chief Executive
Officer or Chief Financial Officer of the Company, which verifies that the Business Combination has been approved by a vote of
the Company’s stockholders, if a vote is held, and (b) joint written instruction signed by the Company and the Representative
with respect to the transfer of the funds held in the Trust Account, including payment of the Deferred Discount from the Trust
Account (the “Instruction Letter”). You are hereby directed and authorized to transfer the funds held
in the Trust Account immediately upon your receipt of the Notification and the Instruction Letter, in accordance with the terms
of the Instruction Letter. In the event that certain deposits held in the Trust Account may not be liquidated by the Consummation
Date without penalty, you will notify the Company in writing of the same and the Company shall direct you as to whether such funds
should remain in the Trust Account and be distributed after the Consummation Date to the Company. Upon the distribution of all
the funds, net of any payments necessary for reasonable unreimbursed expenses related to liquidating the Trust Account, your obligations
under the Trust Agreement shall be terminated.


 


In
the event that the Business Combination is not consummated on the Consummation Date described in the notice thereof and we have
not notified you on or before the original Consummation Date of a new Consummation Date, then upon receipt by the Trustee of written
instructions from the Company, the funds held in the Trust Account shall be reinvested as provided in Section 1(c) of the Trust
Agreement on the business day immediately following the Consummation Date as set forth in the notice as soon thereafter as possible.


 


	 	Very truly yours,
	 	 
	 	FirstMark Horizon Acquisition Corp.
	 	 	 
	 	By: 	     
	 	Name:	 
	 	Title:	 








 


		cc:	Credit
Suisse Securities (USA) LLC



 




     


     


    

 


EXHIBIT
B


 


[Letterhead
of Company]


 


[Insert
date]


 


Continental
Stock Transfer & Trust Company


One
State Street, 30th Floor


New
York, New York 10004


Attn:
Francis Wolf & Celeste Gonzalez


 


		Re:	Trust
Account – Termination Letter



 


Dear
Mr. Wolf and Ms. Gonzalez:


 


Pursuant
to Section 1(i) of the Investment Management Trust Agreement between FirstMark Horizon Acquisition Corp. (the “Company”)
and Continental Stock Transfer & Trust Company (the “Trustee”), dated as of [●], 2020 (the
“Trust Agreement”), this is to advise you that the Company has been unable to effect a business combination
with a target business (the “Business Combination”) within the time frame specified in the Company’s
amended and restated certificate of incorporation, as described in the Company’s Prospectus relating to the Offering. Capitalized
terms used but not defined herein shall have the meanings set forth in the Trust Agreement.


 


In
accordance with the terms of the Trust Agreement, we hereby authorize you to liquidate all of the assets in the Trust Account
and to transfer the total proceeds into the trust operating account at J.P. Morgan Chase Bank, N.A. to await distribution to the
Public Stockholders. The Company has selected _______________ as the effective date for the purpose of determining when the Public
Stockholders will be entitled to receive their share of the liquidation proceeds. You agree to be the Paying Agent of record and,
in your separate capacity as Paying Agent, agree to distribute said funds directly to the Company’s Public Stockholders
in accordance with the terms of the Trust Agreement and the amended and restated certificate of incorporation of the Company.
Upon the distribution of all the funds, your obligations under the Trust Agreement shall be terminated, except to the extent otherwise
provided in Section 1(j) of the Trust Agreement.


 


	 	Very truly yours,
	 	 
	 	FirstMark Horizon Acquisition Corp.
	 	 	 
	 	By: 	  
	 	Name:	 
	 	Title:	 









 


		cc:	Credit
Suisse Securities (USA) LLC



 




     


     


    

 


EXHIBIT
C


 


[Letterhead
of Company]


 


[Insert
date]


 


Continental
Stock Transfer & Trust Company


One
State Street, 30th Floor


New
York, New York 10004


Attn:
Francis Wolf & Celeste Gonzalez


 


		Re:	Trust
Account – Tax Payment Withdrawal Instruction



 


Dear
Mr. Wolf and Ms. Gonzalez:


 


Pursuant
to Section 1(j) of the Investment Management Trust Agreement between FirstMark Horizon Acquisition Corp. (the “Company”)
and Continental Stock Transfer & Trust Company (the “Trustee”), dated as of [●], 2020 (the
“Trust Agreement”), the Company hereby requests that you deliver to the Company $____________ of the
interest income earned on the Property as of the date hereof. Capitalized terms used but not defined herein shall have the meanings
set forth in the Trust Agreement.


 


The
Company needs such funds to pay for the tax obligations as set forth on the attached tax return or tax statement. In accordance
with the terms of the Trust Agreement, you are hereby directed and authorized to transfer (via wire transfer) such funds promptly
upon your receipt of this letter to the Company’s operating account at:


 


[WIRE
INSTRUCTION INFORMATION]


 


	 	Very truly yours,
	 	 
	 	FirstMark Horizon Acquisition Corp.
	 	 	 
	 	By: 	       
	 	Name:	 
	 	Title:	 






 


		cc:	Credit
Suisse Securities (USA) LLC



 




     


     


    

 


EXHIBIT
D


 


[Letterhead
of Company]


 


[Insert
date]


 


Continental
Stock Transfer & Trust Company


One
State Street, 30th Floor


New
York, New York 10004


Attn:
Francis Wolf & Celeste Gonzalez


 


		Re:	Trust
Account – Stockholder Redemption Withdrawal Instruction



 


Dear
Mr. Wolf and Ms. Gonzalez:


 


Pursuant
to Section 1(k) of the Investment Management Trust Agreement between FirstMark Horizon Acquisition Corp. (the “Company”)
and Continental Stock Transfer & Trust Company (the “Trustee”), dated as of [●], 2020 (the
“Trust Agreement”), the Company hereby requests that you deliver to the redeeming Public Stockholders
on behalf of the Company $___________ of the principal and interest income earned on the Property as of the date hereof. Capitalized
terms used but not defined herein shall have the meanings set forth in the Trust Agreement.


 


The
funds as described above are needed to pay the Public Stockholders who have properly elected to have their shares of Common Stock
redeemed by the Company in connection with a stockholder vote to approve an amendment to the Company’s amended and restated
certificate of incorporation (A) to modify the substance or timing of the Company’s obligation to allow redemptions in connection
with its initial Business Combination or to redeem 100% of the Company’s public shares of Common Stock if the Company does
not complete its initial Business Combination within the time period set forth therein or (B) with respect to any other provision
relating to the Company’s stockholders’ rights or pre-initial Business Combination activity. As such, you are hereby
directed and authorized to transfer (via wire transfer) such funds promptly upon your receipt of this letter to the redeeming
Public Stockholders in accordance with your customary procedures.


 





	 	Very truly yours,
	 	 
	 	FirstMark Horizon Acquisition Corp.
	 	 	 
	 	By: 	      
	 	Name:	 
	 	Title:	 



 





		cc:	Credit
Suisse Securities (USA) LLC