Document:

Exhibit 10.5

 

EXECUTION VERSION

 

FirstMark Horizon Acquisition Corp.

100 5th Avenue, 3rd Floor

New York, New York 10011

 

	FirstMark Horizon Sponsor LLC	August 18, 2020

100 5th Avenue, 3rd Floor

New York, New York 10011

 

		RE:	Securities Subscription Agreement

 

Ladies and Gentlemen:

 

FirstMark Horizon Acquisition Corp., a Delaware
corporation (the “Company”), is pleased to accept the offer FirstMark Horizon Sponsor LLC, a Delaware limited
liability company (the “Subscriber” or “you”), has made to purchase 8,625,000 shares of
the Company’s Class B common stock (the “Shares”), par value $0.0001 per share (“Class B Common
Stock”), up to 1,125,000 of which are subject to complete or partial forfeiture by you if the underwriters of the Company’s
initial public offering (“IPO”), if any, do not fully exercise their over-allotment option (the “Over-allotment
Option”). For the purposes of this Agreement (this “Agreement”), references to “Common Stock”
are to, collectively, the Class B Common Stock and the Company’s Class A common stock, par value $0.0001 per share (“Class
A Common Stock”). Pursuant to the Company’s certificate of incorporation, as amended to the date hereof (the “Charter”),
shares of Class B Common Stock will automatically convert into shares of Class A Common Stock on a one-for-one basis, subject
to adjustment, upon the terms and conditions set forth in the Charter. Unless the context otherwise requires, as used herein “Securities”
shall refer to the Shares and shall be deemed to include any shares of Class A Common Stock issued upon conversion of the Shares.
The terms on which the Company is willing to sell the Shares to the Subscriber, and the Company and the Subscriber’s agreements
regarding such Shares, are as follows:

 

1. Purchase of Shares.

 

For the sum of $25,000 (the “Purchase
Price”), which the Company acknowledges receiving in cash, the Company hereby sells and issues the Shares to the Subscriber,
and the Subscriber hereby purchases the Shares from the Company, subject to the forfeiture provisions of Section 3, on the terms
and subject to the conditions set forth in this Agreement. Concurrently with the Subscriber’s execution of this Agreement,
the Company shall, at its option, deliver to the Subscriber a certificate registered in the Subscriber’s name representing
the Shares (the “Original Certificate”), or effect such delivery in book-entry form.

 

     

     

    

 

2. Representations, Warranties and Agreements.

 

2.1 Subscriber’s Representations,
Warranties and Agreements. To induce the Company to issue the Securities to the Subscriber, the Subscriber hereby represents
and warrants to the Company and agrees with the Company as follows:

 

2.1.1 No Government Recommendation or Approval.
The Subscriber understands that no federal or state agency has passed upon or made any recommendation or endorsement of the offering
of the Securities.

 

2.1.2 No Conflicts. The execution,
delivery and performance of this Agreement and the consummation by the Subscriber of the transactions contemplated hereby do not
violate, conflict with or constitute a default under (i) the formation and governing documents of the Subscriber, (ii) any agreement,
indenture or instrument to which the Subscriber is a party, (iii) any law, statute, rule or regulation to which the Subscriber
is subject or (iv) any agreement, order, judgment or decree to which the Subscriber is subject.

 

2.1.3 Organization and Authority. The
Subscriber is a Delaware limited liability company, validly existing and in good standing under the laws of the State of Delaware
and possesses all requisite power and authority necessary to carry out the transactions contemplated by this Agreement. Upon execution
and delivery by you, this Agreement is a legal, valid and binding agreement of the Subscriber, enforceable against the Subscriber
in accordance with its terms, except as such enforceability may be limited by applicable bankruptcy, insolvency, fraudulent conveyance
or similar laws affecting the enforcement of creditors’ rights generally and subject to general principles of equity (regardless
of whether enforcement is sought in a proceeding at law or in equity).

 

2.1.4 Experience, Financial Capability
and Suitability. The Subscriber is: (i) sophisticated in financial matters and is able to evaluate the risks and benefits of
the investment in the Securities and (ii) able to bear the economic risk of its investment in the Securities for an indefinite
period of time because the Securities have not been registered under the Securities Act (as defined below) and therefore cannot
be sold unless subsequently registered under the Securities Act or an exemption from such registration is available. The Subscriber
is capable of evaluating the merits and risks of its investment in the Company and has the capacity to protect its own interests.
The Subscriber must bear the economic risk of this investment until the Securities are sold pursuant to: (x) an effective registration
statement under the Securities Act or (y) an exemption from registration available with respect to such sale. The Subscriber is
able to bear the economic risks of an investment in the Securities and to afford a complete loss of the Subscriber’s investment
in the Securities.

 

2.1.5 Access to Information; Independent
Investigation. Prior to the execution of this Agreement, the Subscriber has had the opportunity to ask questions of and receive
answers from representatives of the Company concerning an investment in the Company, as well as the finances, operations, business
and prospects of the Company, and the opportunity to obtain additional information to verify the accuracy of all information so
obtained. In determining whether to make this investment, the Subscriber has relied solely on the Subscriber’s own knowledge
and understanding of the Company and its business based upon the Subscriber’s own due diligence investigation and the information
furnished pursuant to this paragraph. The Subscriber understands that no person has been authorized to give any information or
to make any representations which were not furnished pursuant to this Section 2 and the Subscriber has not relied on any other
representations or information in making its investment decision, whether written or oral, relating to the Company, its operations
and/or its prospects.

 

    2

     

    

 

2.1.6 Private Placement. The Subscriber
represents that it is an “accredited investor” as such term is defined in Rule 501(a) of Regulation D under the Securities
Act of 1933, as amended (the “Securities Act”), and acknowledges the sale contemplated hereby is being made
in reliance on a private placement exemption applicable to “accredited investors” within the meaning of Section 501(a)
of Regulation D under the Securities Act or similar exemptions under state law.

 

2.1.7 Investment Purposes. The Subscriber
is purchasing the Securities solely for investment purposes, for the Subscriber’s own account and not for the account or
benefit of any other person, and not with a view towards the distribution or dissemination thereof. The Subscriber did not decide
to enter into this Agreement as a result of any general solicitation or general advertising within the meaning of Rule 502 under
the Securities Act.

 

2.1.8 Restrictions on Transfer; Shell Company.
The Subscriber understands the Securities are being offered in a transaction not involving a public offering within the meaning
of the Securities Act. The Subscriber understands the Securities will be “restricted securities” within the meaning
of Rule 144(a)(3) under the Securities Act and the Subscriber understands that the certificates or book-entries representing the
Securities will contain a legend in respect of such restrictions. If in the future the Subscriber decides to offer, resell, pledge
or otherwise transfer the Securities, such Securities may be offered, resold, pledged or otherwise transferred only pursuant to:
(i) registration under the Securities Act, or (ii) an available exemption from registration. The Subscriber agrees that if any
transfer of its Securities or any interest therein is proposed to be made, as a condition precedent to any such transfer, the Subscriber
may, at the Company’s option, be required to deliver to the Company an opinion of counsel satisfactory to the Company. Absent
registration or an exemption, the Subscriber agrees not to resell the Securities. The Subscriber further acknowledges that because
the Company is a shell company, Rule 144 may not be available to the Subscriber for the resale of the Shares until at least one
year following consummation of the initial business combination of the Company (which may not occur), despite technical compliance
with the requirements of Rule 144 and the release or waiver of any contractual transfer restrictions.

 

2.1.9 No Governmental Consents. No
governmental, administrative or other third party consents or approvals are required, necessary or appropriate on the part of the
Subscriber in connection with the transactions contemplated by this Agreement.

 

2.2 Company’s Representations,
Warranties and Agreements. To induce the Subscriber to purchase the Securities, the Company hereby represents and warrants
to the Subscriber and agrees with the Subscriber as follows:

 

2.2.1 Organization and Corporate Power.
The Company is a Delaware corporation and is qualified to do business in every jurisdiction in which the failure to so qualify
would reasonably be expected to have a material adverse effect on the financial condition, operating results or assets of the Company.
The Company possesses all requisite corporate power and authority necessary to carry out the transactions contemplated by this
Agreement.

 

    3

     

    

 

2.2.2 No Conflicts. The execution,
delivery and performance of this Agreement and the consummation by the Company of the transactions contemplated hereby do not violate,
conflict with or constitute a default under (i) the Charter or bylaws of the Company, (ii) any agreement, indenture or instrument
to which the Company is a party, (iii) any law, statute, rule or regulation to which the Company is subject, or (iv) any
agreement, order, judgment or decree to which the Company is subject.

 

2.2.3 Title to Securities. Upon issuance
in accordance with, and payment pursuant to, the terms hereof, the Securities will be duly and validly issued, fully paid and nonassessable.
Upon issuance in accordance with, and payment pursuant to, the terms hereof, the Subscriber will have or receive good title to
the Securities, free and clear of all liens, claims and encumbrances of any kind, other than (a) transfer restrictions hereunder
and under the other agreements to which the Securities may be subject which have been notified to the Subscriber in writing, (b)
transfer restrictions under federal and state securities laws, and (c) liens, claims or encumbrances imposed due to the actions
of the Subscriber.

 

2.2.4 No Adverse Actions. There are
no actions, suits, investigations or proceedings pending, threatened against or affecting the Company which: (i) seek to restrain,
enjoin, prevent the consummation of or otherwise affect the transactions contemplated by this Agreement or (ii) question the validity
or legality of any transactions or seek to recover damages or to obtain other relief in connection with any transactions.

 

2.2.5 Authorization. The shares of
Class A Common Stock issuable upon conversion of the Shares have been duly authorized and reserved for issuance upon such conversion.

 

3. Forfeiture of Shares.

 

3.1 Partial or No Exercise of the Over-allotment
Option. In the event the Over-allotment Option granted to the underwriters of the IPO is not exercised in full, the Subscriber
acknowledges and agrees that it (or, if applicable, it and any transferees of Shares) shall automatically forfeit at the time
such Over-allotment Option expires (or earlier if the underwriters of the IPO waive their ability to exercise such Over-allotment
Option) any and all rights to such number of Shares (up to an aggregate of 1,125,000 Shares and pro rata based upon the percentage
of the Over-allotment Option exercised) such that immediately following such forfeiture, the aggregate number of Shares owned
by the Subscriber (and any such transferees) will equal 20% of the issued and outstanding Common Stock immediately following the
IPO (not including Class A Common Stock issuable upon exercise of any warrants or underlying any units or warrants issued in a
private placement in connection with the IPO).

 

    4

     

    

 

3.2 Termination of Rights as Stockholder.
If any of the Shares are forfeited in accordance with this Section 3, then after such time the Subscriber (or its successor in
interest), shall no longer have any rights as a holder of such forfeited Shares, and the Company shall take such action as is
appropriate to cancel such forfeited Shares.

 

3.3 Share Certificates. In the event
an adjustment to the Original Certificates, if any, is required pursuant to this Section 3, then the Subscriber shall return such
Original Certificates to the Company or its designated agent as soon as practicable upon its receipt of notice from the Company
advising the Subscriber of such adjustment, following which a new certificate (the “New Certificate”), if any,
shall be issued in such amount representing the adjusted number of Shares held by the Subscriber. The New Certificate, if any,
shall be returned to the Subscriber as soon as practicable. Any such adjustment for any uncertificated securities held by the
Subscriber shall be made in book-entry form.

 

4. Waiver of Liquidation Distributions;
Redemption Rights. In connection with the Shares purchased pursuant to this Agreement, the Subscriber hereby waives any and
all right, title, interest or claim of any kind in or to any distributions by the Company from the trust account which will be
established for the benefit of the Company’s public stockholders and into which substantially all of the proceeds of the
IPO will be deposited (the “Trust Account”), in the event of a liquidation of the Company upon the Company’s
failure to timely complete an initial business combination. For purposes of clarity, in the event the Subscriber purchases securities
in the IPO or in the aftermarket, any shares of Class A Common Stock so purchased shall be eligible to receive any liquidating
distributions by the Company. However, in no event will the Subscriber have the right to redeem any shares of Common Stock held
by it into funds held in the Trust Account upon the successful completion of an initial business combination. For the avoidance
of doubt, the foregoing shall not restrict the right of any affiliate of the Subscriber to redeem any shares of Class A Common
Stock purchased in the IPO or aftermarket by such affiliate of the Subscriber.

 

5. Restrictions on Transfer.

 

5.1 Securities Law Restrictions.
In addition to any restrictions to be contained in that certain letter agreement (commonly known as an “Insider Letter”)
dated on or prior to the closing of the IPO by and among the Subscriber, the Company and other parties thereto, the Subscriber
agrees not to sell, transfer, pledge, hypothecate or otherwise dispose of all or any part of the Securities unless, prior thereto
(a) a registration statement on the appropriate form under the Securities Act and applicable state securities laws with respect
to the Securities proposed to be transferred shall then be effective or (b) the Company has received, if requested by the Company,
an opinion from counsel reasonably satisfactory to the Company, that such registration is not required because such transaction
is exempt from registration under the Securities Act and the rules promulgated by the Securities and Exchange Commission thereunder
and with all applicable state securities laws.

 

5.2 Lock-up. The Subscriber acknowledges
that the Securities will be subject to lock-up provisions (the “Lock-up”) contained in the Insider Letter.
Pursuant to the Insider Letter, the Subscriber will agree (subject to certain customary exceptions) not to sell, transfer, pledge,
hypothecate or otherwise dispose of all or any part of the Securities until the earlier to occur of: (a) one year after the completion
of the Company’s initial business combination, (b) if the last sale price of the Class A 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 the Company’s initial business combination and
(c) the date on which the Company consummates a liquidation, merger, capital stock exchange, reorganization or other similar transaction
after the Company’s initial business combination 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.

 

    5

     

    

 

5.3 Restrictive Legends. All certificates
representing the Securities shall have endorsed thereon legends substantially as follows:

 

“THE SECURITIES REPRESENTED HEREBY
HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAWS AND NEITHER THE SECURITIES
NOR ANY INTEREST THEREIN MAY BE OFFERED, SOLD, TRANSFERRED, PLEDGED OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION
STATEMENT UNDER SUCH ACT OR SUCH LAWS OR AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT AND SUCH LAWS WHICH, IN THE OPINION OF COUNSEL
(IF THE COMPANY SO REQUESTS), IS AVAILABLE.” 

 

“THE SECURITIES REPRESENTED BY THIS
CERTIFICATE ARE SUBJECT TO A LOCKUP AND MAY NOT BE OFFERED, SOLD, TRANSFERRED, PLEDGED OR OTHERWISE DISPOSED DURING THE TERM OF
THE LOCKUP.” 

 

5.4 Additional Shares or Substituted
Securities. In the event of the declaration of a share dividend, the declaration of an extraordinary dividend payable in a
form other than Common Stock, a spin-off, a stock split, an adjustment in conversion ratio, a recapitalization or a similar transaction
affecting the Company’s outstanding Common Stock without receipt of consideration, any new, substituted or additional securities
or other property which are by reason of such transaction distributed with respect to any Securities subject to this Section 5
or into which such Securities thereby become convertible shall immediately be subject to this Section 5 and Section 3. Appropriate
adjustments to reflect the distribution of such securities or property shall be made to the number and/or class of Securities
subject to this Section 5 and Section 3.

 

5.5 Registration Rights. The Subscriber
acknowledges that the Shares are being purchased pursuant to an exemption from the registration requirements of the Securities
Act and will become freely tradable only after certain conditions are met or they are registered pursuant to a registration rights
agreement to be entered into with the Company prior to the closing of the IPO (the “Registration Rights Agreement”).

 

6. Other Agreements.

 

6.1 Further Assurances. The Subscriber
agrees to execute such further instruments and to take such further action as may reasonably be necessary to carry out the intent
of this Agreement.

 

    6

     

    

 

6.2 Notices. All notices, statements
or other documents which are required or contemplated by this Agreement shall be in writing and delivered (i) 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, and (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.

 

6.3 Entire Agreement. This Agreement,
together with that certain Insider Letter to be entered into between the Subscriber and the Company and the Registration Rights
Agreement, each substantially in the form to be filed as an exhibit to the Registration Statement, embodies the entire agreement
and understanding between the Subscriber and the Company with respect to the subject matter hereof and supersedes all prior oral
or written agreements and understandings relating to the subject matter hereof. No statement, representation, warranty, covenant
or agreement of any kind not expressly set forth in this Agreement shall affect, or be used to interpret, change or restrict,
the express terms and provisions of this Agreement.

 

6.4 Modifications and Amendments.
The terms and provisions of this Agreement may be modified or amended only by written agreement executed by all parties hereto.

 

6.5 Waivers and Consents. The terms
and provisions of this Agreement may be waived, or consent for the departure therefrom granted, only by written document executed
by the party entitled to the benefits of such terms or provisions. No such waiver or consent shall be deemed to be or shall constitute
a waiver or consent with respect to any other terms or provisions of this Agreement, whether or not similar. Each such waiver
or consent shall be effective only in the specific instance and for the purpose for which it was given, and shall not constitute
a continuing waiver or consent.

 

6.6 Assignment. The rights and obligations
under this Agreement may not be assigned by either party hereto without the prior written consent of the other party.

 

6.7 Benefit. All statements, representations,
warranties, covenants and agreements in this Agreement shall be binding on the parties hereto and shall inure to the benefit of
the respective successors and permitted assigns of each party hereto. Nothing in this Agreement shall be construed to create any
rights or obligations except among the parties hereto, and no person or entity shall be regarded as a third-party beneficiary
of this Agreement.

 

6.8 Governing Law. This Agreement
and the rights and obligations of the parties hereunder shall be construed in accordance with and governed by the laws of the
State of Delaware applicable to contracts wholly performed within the borders of such state.

 

6.9 Severability. In the event that
any court of competent jurisdiction shall determine that any provision, or any portion thereof, contained in this Agreement shall
be unreasonable or unenforceable in any respect, then such provision shall be deemed limited to the extent that such court deems
it reasonable and enforceable, and as so limited shall remain in full force and effect. In the event that such court shall deem
any such provision, or portion thereof, wholly unenforceable, the remaining provisions of this Agreement shall nevertheless remain
in full force and effect.

 

    7

     

    

 

6.10 No Waiver of Rights, Powers and
Remedies. No failure or delay by a party hereto in exercising any right, power or remedy under this Agreement, and no course
of dealing between the parties hereto, shall operate as a waiver of any such right, power or remedy of such party. No single or
partial exercise of any right, power or remedy under this Agreement by a party hereto, nor any abandonment or discontinuance of
steps to enforce any such right, power or remedy, shall preclude such party from any other or further exercise thereof or the
exercise of any other right, power or remedy hereunder. The election of any remedy by a party hereto shall not constitute a waiver
of the right of such party to pursue other available remedies. No notice to or demand on a party not expressly required under
this Agreement shall entitle the party receiving such notice or demand to any other or further notice or demand in similar or
other circumstances or constitute a waiver of the rights of the party giving such notice or demand to any other or further action
in any circumstances without such notice or demand.

 

6.11 Survival of Representations and
Warranties. All representations and warranties made by the parties hereto in this Agreement or in any other agreement, certificate
or instrument provided for or contemplated hereby, shall survive the execution and delivery hereof and any investigations made
by or on behalf of the parties.

 

6.12 No Broker or Finder. Each of
the parties hereto represents and warrants to the other that no broker, finder or other financial consultant has acted on its
behalf in connection with this Agreement or the transactions contemplated hereby in such a way as to create any liability on the
other. Each of the parties hereto agrees to indemnify and save the other harmless from any claim or demand for commission or other
compensation by any broker, finder, financial consultant or similar agent claiming to have been employed by or on behalf of such
party and to bear the cost of legal expenses incurred in defending against any such claim.

 

6.13 Headings and Captions. The
headings and captions of the various subdivisions of this Agreement are for convenience of reference only and shall in no way
modify or affect the meaning or construction of any of the terms or provisions hereof.

 

6.14 Counterparts. This Agreement
may be executed in one or more counterparts, all of which when taken together shall be considered one and the same agreement and
shall become effective when counterparts have been signed by each party and delivered to the other party, it being understood
that both parties need not sign the same counterpart. In the event that any signature is delivered by facsimile transmission or
any other form of electronic delivery, such signature shall create a valid and binding obligation of the party executing (or on
whose behalf such signature is executed) with the same force and effect as if such signature page were an original thereof.

 

    8

     

    

 

6.15 Construction. The parties hereto
have participated jointly in the negotiation and drafting of this Agreement. If an ambiguity or question of intent or interpretation
arises, this Agreement will be construed as if drafted jointly by the parties hereto and no presumption or burden of proof will
arise favoring or disfavoring any party hereto because of the authorship of any provision of this Agreement. The words “include,”
“includes,” and “including” will be deemed to be followed by “without limitation.” Pronouns
in masculine, feminine, and neuter genders will be construed to include any other gender, and words in the singular form will
be construed to include the plural and vice versa, unless the context otherwise requires. The words “this Agreement,”
“herein,” “hereof,” “hereby,” “hereunder,” and words of similar import refer to
this Agreement as a whole and not to any particular subdivision unless expressly so limited. The parties hereto intend that each
representation, warranty, and covenant contained herein will have independent significance. If any party hereto has breached any
representation, warranty, or covenant contained herein in any respect, the fact that there exists another representation, warranty
or covenant relating to the same subject matter (regardless of the relative levels of specificity) which such party hereto has
not breached will not detract from or mitigate the fact that such party hereto is in breach of the first representation, warranty,
or covenant.

 

6.16 Mutual Drafting. This Agreement
is the joint product of the Subscriber 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.

 

7. Voting and Tender of Shares. The
Subscriber agrees to vote the Shares in favor of an initial business combination that the Company negotiates and submits for approval
to the Company’s stockholders and shall not seek redemption with respect to any of the Shares in connection with an initial
business combination or any amendment to the Charter, as amended, prior to an initial business combination. Additionally, the
Subscriber agrees not to tender any Shares in connection with a tender offer presented to the Company’s stockholders in
connection with an initial business combination negotiated by the Company.

 

8. Indemnification. Each party shall
indemnify the other against any loss, cost or damages (including reasonable attorney’s fees and expenses) incurred as a
result of such party’s breach of any representation, warranty, covenant or agreement in this Agreement.

 

[Signature page follows]

 

    9

     

    

 

If the foregoing accurately sets forth our
understanding and agreement, please sign the enclosed copy of this Agreement and return it to us.

 

	 	Very truly yours,
	 	 
	 	FIRSTMARK HORIZON ACQUISITION CORP.
	 	 	 
	 	By:	/s/ Eric Cheung
	 	 	Name: Eric Cheung
	 	 	Title: Secretary

 

 

FIRSTMARK HORIZON SPONSOR
LLC

 

By: FirstMark Capital LLC, as sole member

 

	By:	/s/ Eric Cheung	 
	 	Name: Eric Cheung	 
	 	Title: General Counsel	 

 

 

 

[Signature Page to Securities Subscription
Agreement]Exhibit
10.6

 

PRIVATE
PLACEMENT WARRANTS PURCHASE AGREEMENT

 

THIS PRIVATE PLACEMENT WARRANTS PURCHASE
AGREEMENT (as it may from time to time be amended and including all exhibits referenced herein, this “Agreement”),
dated as of [●], 2020, is entered into by and between FirstMark Horizon Acquisition
Corp., a Delaware corporation (the “Company”), and FirstMark Horizon Sponsor LLC, a Delaware limited
liability company (the “Purchaser”).

 

WHEREAS, the Company intends to consummate
an initial public offering of the Company’s units (the “Public Offering”), each unit consisting
of one share of Class A common stock of the Company, par value $0.0001 per share (a “Share”), and one-third
of one redeemable warrant, each whole warrant entitling the holder to purchase one Share at an exercise price of $11.50 per Share,
as set forth in the Company’s Registration Statement on Form S-1, as amended, filed with the U.S. Securities and Exchange
Commission, No. 333-[●] (the “Registration Statement”),
under the Securities Act of 1933, as amended (the “Securities Act”).

 

WHEREAS, the Purchaser has agreed to purchase,
at a price of $1.50 per warrant, an aggregate of 5,333,333 warrants (and up to 5,933,333 warrants if the underwriters in the Public
Offering exercise their over-allotment option in full) (the “Private Placement Warrants”), each Private
Placement Warrant entitling the holder to purchase one Share at an exercise price of $11.50 per Share.

 

NOW THEREFORE, in consideration of the mutual
promises contained in this Agreement and other good and valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties to this Agreement hereby, intending legally to be bound, agree as follows:

 

AGREEMENT

 

Section 1. Authorization, Purchase
and Sale; Terms of the Private Placement Warrants.

 

A. Authorization
of the Private Placement Warrants. The Company has duly authorized the issuance and sale of the Private Placement Warrants,
and, subject to proper exercise of the Private Placement Warrants and against payment therefor, the Shares underlying such Private
Placement Warrants, to the Purchaser.

 

B. Purchase
and Sale of the Private Placement Warrants.

 

(i) On the date of the consummation of the
Public Offering or on such earlier time and date as may be mutually agreed by the Purchaser and the Company (the “IPO
Closing Date”), the Company shall issue and sell to the Purchaser, and the Purchaser shall purchase from the Company,
5,333,333 Private Placement Warrants at a price of $1.50 per Private Placement Warrant for an aggregate purchase price of $8,000,000
(the “Purchase Price”). The Purchaser shall pay, at least one (1) business day prior to the IPO Closing
Date, the Purchase Price by wire transfer of immediately available funds, to accounts designated by the Company, including to the
trust account (the “Trust Account”), at a financial institution to be chosen by the Company, maintained
by Continental Stock Transfer & Trust Company, acting as trustee, in accordance with the Company’s wiring instructions.
On the IPO Closing Date, subject to receipt of funds pursuant to the immediately prior sentence, the Company shall effect such
delivery in book-entry form.

 

     

     

    

 

(ii) On the date of the consummation of the
closing of the over-allotment option, if any, in connection with the Public Offering or on such earlier time and date as may be
mutually agreed by the Purchaser and the Company (an “Over-allotment Closing Date,” and each Over-allotment
Closing Date (if any) and the IPO Closing Date, a “Closing Date”), the Company shall issue and sell to
the Purchaser, and the Purchaser shall purchase from the Company, up to 600,000 Private Placement Warrants (or, to the extent the
over-allotment option is not exercised in full, a lesser number of Private Placement Warrants in proportion to the portion of the
over-allotment option that is then exercised) at a price of $1.50 per Private Placement Warrant for an aggregate purchase price
of up to $900,000 (if the over-allotment option is exercised in full) (the “Over-allotment Purchase Price”).
The Purchaser shall pay the Over-allotment Purchase Price in accordance with the Company’s wire instruction by wire transfer
of immediately available funds to the Company or the Trust Account (as set forth in the wire instructions), at least one (1) business
day prior to the applicable Over-allotment Closing Date. On each Over-allotment Closing Date, subject to receipt of funds pursuant
to the immediately prior sentence, the Company shall effect such delivery in book-entry form.

 

C. Terms
of the Private Placement Warrants.

 

(i) The Private Placement Warrants are substantially
identical to the warrants underlying the units to be offered in the Public Offering except that (a) the Private Placement Warrants
(including the underlying Shares issuable upon exercise of the Private Placement Warrants) will not, except in limited circumstances,
be transferable or salable until 30 days after the completion of the Company’s initial business combination (the “Business
Combination”) so long as they are held by the Purchaser or its permitted transferees, and (b) the Private Placement
Warrants are being purchased pursuant to an exemption from the registration requirements of the Securities Act and will become
freely tradable only after the expiration of the lockup described above in clause (a) and they are registered pursuant to the Registration
Rights Agreement (as defined below) or an exemption from registration is available, and the restrictions described above in clause
(a) have expired and (c) each Private Placement Warrant shall have the terms set forth for private placement warrants in a
Warrant Agreement to be entered into by the Company and a warrant agent in connection with the Public Offering (the “Warrant
Agreement”).

 

(ii) On or prior to the IPO Closing Date,
the Company and the Purchaser shall enter into a registration rights agreement (the “Registration Rights Agreement”)
pursuant to which the Company will grant certain registration rights to the Purchaser relating to the Private Placement Warrants
and the Shares underlying the Private Placement Warrants.

 

    2

     

    

 

Section 2. Representations and Warranties
of the Company.

 

As a material inducement to the Purchaser
to enter into this Agreement and purchase the Private Placement Warrants, the Company hereby represents and warrants to the Purchaser
(which representations and warranties shall survive each Closing Date) that:

 

A. Incorporation
and Corporate Power. The Company is a corporation duly incorporated, validly existing and in good standing under the
laws of the State of Delaware and is qualified to do business in every jurisdiction in which the failure to so qualify would reasonably
be expected to have a material adverse effect on the financial condition, operating results or assets of the Company. The Company
possesses all requisite corporate power and authority necessary to carry out the transactions contemplated by this Agreement and
the Warrant Agreement.

 

B. Authorization;
No Breach.

 

(i) The execution, delivery and performance
of this Agreement and the Private Placement Warrants, and, subject to proper exercise of the Private Placement Warrants and against
payment therefor, the Shares underlying such Private Placement Warrants, have been duly authorized by the Company. This Agreement
constitutes the valid and binding obligation of the Company, enforceable in accordance with its terms, subject to bankruptcy, insolvency,
fraudulent conveyance, reorganization, moratorium and other laws of general applicability relating to or affecting creditors’
rights and to general equitable principles (whether considered in a proceeding in equity or law). Upon issuance in accordance with,
and payment pursuant to, the terms of the Warrant Agreement and this Agreement, the Private Placement Warrants, will constitute
valid and binding obligations of the Company, enforceable in accordance with their terms as of each Closing Date.

 

(ii) The execution and delivery by the Company
of this Agreement and the Private Placement Warrants, the issuance and sale of the Private Placement Warrants, the issuance of
the Shares upon exercise of the Private Placement Warrants and the fulfillment of and compliance with the respective terms hereof
and thereof by the Company, do not and will not as of each Closing Date (a) conflict with or result in a breach of the terms, conditions
or provisions of, (b) constitute a default under, (c) result in the creation of any lien, security interest, charge or encumbrance
upon the Company’s capital stock or assets under, (d) result in a violation of, or (e) require any authorization, consent,
approval, exemption or other action by or notice or declaration to, or filing with, any court or administrative or governmental
body or agency pursuant to the Company’s amended and restated certificate of incorporation and bylaws (each, in effect on
the date hereof or as may be amended prior to completion of the contemplated Public Offering) or any material law, statute, rule
or regulation to which the Company is subject, or any agreement, order, judgment or decree to which the Company is subject, except
for any filings required after the date hereof under federal or state securities laws.

 

C. Title
to Securities. Upon issuance in accordance with, and payment pursuant to, the terms hereof and the Warrant Agreement,
the Shares issuable upon exercise of the Private Placement Warrants will be duly and validly issued, fully paid and nonassessable.
On the date of issuance of the Private Placement Warrants, the Shares issuable upon exercise of the Private Placement Warrants
shall have been reserved for issuance. Upon issuance in accordance with, and payment pursuant to, the terms hereof and the Warrant
Agreement (as applicable), the Purchaser will have good title to the Private Placement Warrants, including the Shares issuable
upon exercise of the Private Placement Warrants, free and clear of all liens, claims and encumbrances of any kind, other than (i)
transfer restrictions hereunder and under the other agreements contemplated hereby, (ii) transfer restrictions under federal and
state securities laws, and (iii) liens, claims or encumbrances imposed due to the actions of the Purchaser.

 

    3

     

    

 

D. Governmental
Consents. Assuming the accuracy of the representations and warranties made by the Purchaser in this Agreement, no consent,
approval, order or authorization of, or registration, qualification, designation, declaration or filing with, any federal, state
or local governmental authority is required on the part of the Company in connection with the consummation of the transactions
contemplated by this Agreement, except for applicable requirements of the Securities Act.

 

Section 3. Representations and Warranties
of the Purchaser.

 

As a material inducement to the Company
to enter into this Agreement and issue and sell the Private Placement Warrants to the Purchaser, the Purchaser hereby represents
and warrants to the Company (which representations and warranties shall survive each Closing Date) that:

 

A. Organization
and Requisite Authority. The Purchaser possesses all requisite power and authority necessary to carry out the transactions
contemplated by this Agreement.

 

B. Authorization;
No Breach.

 

(i) This Agreement constitutes a valid and
binding obligation of the Purchaser, enforceable in accordance with its terms, subject to bankruptcy, insolvency, fraudulent conveyance,
reorganization, moratorium and other laws of general applicability relating to or affecting creditors’ rights and to general
equitable principles (whether considered in a proceeding in equity or law).

 

(ii) The execution and delivery by the Purchaser
of this Agreement and the fulfillment of and compliance with the terms hereof by the Purchaser do not and shall not as of each
Closing Date (a) conflict with or result in a breach by the Purchaser of the terms, conditions or provisions of, (b) constitute
a default under, (c) result in the creation of any lien, security interest, charge or encumbrance upon the Purchaser’s equity
or assets under, (d) result in a violation of, or (e) require any authorization, consent, approval, exemption or other action by
or notice or declaration to, or filing with, any court or administrative or governmental body or agency pursuant to the Purchaser’s
organizational documents in effect on the date hereof or as may be amended prior to completion of the contemplated Public Offering,
or any material law, statute, rule or regulation to which the Purchaser is subject, or any agreement, instrument, order, judgment
or decree to which the Purchaser is subject, except for any filings required after the date hereof under federal or state securities
laws.

 

C. Investment
Representations.

 

(i) The Purchaser is acquiring the Private
Placement Warrants, and, upon exercise of the Private Placement Warrants, the Shares issuable upon such exercise (collectively,
the “Securities”) for its own account, for investment purposes only and not with a view towards, or for
resale in connection with, any public sale or distribution thereof.

 

    4

     

    

 

(ii) The Purchaser understands that the Securities
are being offered and will be sold to it in reliance on specific exemptions from the registration requirements of the United States
federal and state securities laws and that the Company is relying upon the truth and accuracy of, and the Purchaser’s compliance
with, the representations and warranties of the Purchaser set forth herein in order to determine the availability of such exemptions
and the eligibility of the Purchaser to acquire such Securities.

 

(iii) The Purchaser is an “accredited
investor” as such term is defined in Rule 501(a)(3) of Regulation D under the Securities Act, and the Purchaser has not experienced
a disqualifying event as enumerated pursuant to Rule 506(d) of Regulation D under the Securities Act. The Purchaser did not decide
to enter into this Agreement as a result of any general solicitation or general advertising within the meaning of Rule 502(c) of
Regulation D under the Securities Act.

 

(iv) The Purchaser has been furnished with
all materials relating to the business, finances and operations of the Company and materials relating to the offer and sale of
the Securities which have been requested by the Purchaser. The Purchaser has been afforded the opportunity to ask questions of
the executive officers and directors of the Company. The Purchaser understands that its investment in the Securities involves a
high degree of risk and it has sought such accounting, legal and tax advice as it has considered necessary to make an informed
investment decision with respect to the acquisition of the Securities.

 

(v) The Purchaser understands that no United
States federal or state agency or any other government or governmental agency has passed on or made any recommendation or endorsement
of the Securities or the fairness or suitability of the investment in the Securities by the Purchaser nor have such authorities
passed upon or endorsed the merits of the offering of the Securities.

 

(vi) The Purchaser understands that: (a) the
Securities have not been and are not being registered under the Securities Act or any state securities laws, and may not be offered
for sale, sold, assigned or transferred unless (1) subsequently registered thereunder or (2) sold in reliance on an exemption therefrom;
(b) except as specifically set forth in the Registration Rights Agreement, neither the Company nor any other person is under any
obligation to register the Securities under the Securities Act or any state securities laws or to comply with the terms and conditions
of any exemption thereunder; and (c) Rule 144 adopted pursuant to the Securities Act will not be available for resale transactions
of the Securities prior to a Business Combination and may not be available for resale transactions of the Securities after a Business
Combination.

 

(vii) The Purchaser has such knowledge and
experience in financial and business matters, knowledge of the high degree of risk associated with investments in the securities
of companies in the development stage such as the Company, is capable of evaluating the merits and risks of an investment in the
Securities and is able to bear the economic risk of an investment in the Securities in the amount contemplated hereunder for an
indefinite period of time. The Purchaser has adequate means of providing for its current financial needs and contingencies and
will have no current or anticipated future needs for liquidity which would be jeopardized by the investment in the Securities.
The Purchaser can afford a complete loss of its investments in the Securities.

 

    5

     

    

 

(viii) The Purchaser understands that the
Private Placement Warrants shall bear the legend substantially in the form set forth in the Warrant Agreement and be subject to
appropriate “stop transfer restrictions”.

 

Section 4. Conditions of the Purchaser’s
Obligations.

 

The obligations of the Purchaser to purchase
and pay for the Private Placement Warrants are subject to the fulfillment, on or before each Closing Date, of each of the following
conditions:

 

A. Representations
and Warranties. The representations and warranties of the Company contained in Section 2 shall be true and correct at
and as of such Closing Date as though then made.

 

B. Performance.
The Company shall have performed and complied with all agreements, obligations and conditions contained in this Agreement that
are required to be performed or complied with by it on or before such Closing Date.

 

C. No
Injunction. No litigation, statute, rule, regulation, executive order, decree, ruling or injunction shall have been
enacted, entered, promulgated or endorsed by or in any court or governmental authority of competent jurisdiction or any self-regulatory
organization having authority over the matters contemplated hereby, which prohibits the consummation of any of the transactions
contemplated by this Agreement or the Warrant Agreement.

 

D. Warrant
Agreement and Registration Rights Agreement. The Company shall have entered into the Warrant Agreement and the Registration
Rights Agreement, in each case on terms satisfactory to the Purchaser.

 

Section 5. Conditions of the Company’s
Obligations.

 

The obligations of the Company to the Purchaser
under this Agreement are subject to the fulfillment, on or before each Closing Date, of each of the following conditions:

 

A. Representations
and Warranties. The representations and warranties of the Purchaser contained in Section 3 shall be true and correct
at and as of such Closing Date as though then made.

 

B. Performance.
The Purchaser shall have performed and complied with all agreements, obligations and conditions contained in this Agreement that
are required to be performed or complied with by the Purchaser on or before such Closing Date.

 

C. Corporate
Consents. The Company shall have obtained the consent of its Board of Directors authorizing the execution, delivery
and performance of this Agreement and the Warrant Agreement and the issuance and sale of the Private Placement Warrants hereunder.

 

D. No
Injunction. No litigation, statute, rule, regulation, executive order, decree, ruling or injunction shall have been
enacted, entered, promulgated or endorsed by or in any court or governmental authority of competent jurisdiction or any self-regulatory
organization having authority over the matters contemplated hereby, which prohibits the consummation of any of the transactions
contemplated by this Agreement or the Warrant Agreement.

 

    6

     

    

 

E. Warrant
Agreement. The Company shall have entered into the Warrant Agreement.

 

Section 6. Termination.

 

This Agreement may be terminated at any
time after December 31, 2020 upon the election by either the Company or the Purchaser upon written notice to the other party if
the closing of the Public Offering has not occurred prior to such date.

 

Section 7. Survival of Representations
and Warranties.

 

All of the representations and warranties
contained herein shall survive the applicable Closing Date.

 

Section 8. Definitions.

 

Terms used but not otherwise defined in
this Agreement shall have the meaning assigned to such terms in the Registration Statement.

 

Section 9. Miscellaneous.

 

A. Successors
and Assigns. Except as otherwise expressly provided herein, all covenants and agreements contained in this Agreement
by or on behalf of any of the parties hereto shall bind and inure to the benefit of the respective successors of the parties hereto
whether so expressed or not. Notwithstanding the foregoing or anything to the contrary herein, the parties may not assign this
Agreement, other than assignments by the Purchaser to affiliates thereof (including, without limitation, one or more of its members).

 

B. Severability.
Whenever possible, each provision of this Agreement shall be interpreted in such manner as to be effective and valid under applicable
law, but if any provision of this Agreement is held to be prohibited by or invalid under applicable law, such provision shall be
ineffective only to the extent of such prohibition or invalidity, without invalidating the remainder of this Agreement.

 

C. Counterparts.
This Agreement may be executed simultaneously in two or more counterparts, none of which need contain the signatures of more than
one party, but all such counterparts taken together shall constitute one and the same agreement. Signatures to this Agreement transmitted
via facsimile or e-mail shall be valid and effective to bind the party so signing.

 

D. Descriptive
Headings; Interpretation. The descriptive headings of this Agreement are inserted for convenience only and do not constitute
a substantive part of this Agreement. The use of the word “including” in this Agreement shall be by way of example
rather than by limitation.

 

E. Governing
Law. This Agreement shall be deemed to be a contract made under the laws of the State of New York and for all purposes
shall be construed in accordance with the internal laws of the State of New York.

 

F. Amendments.
This Agreement may not be amended, modified or waived as to any particular provision, except by a written instrument executed by
the parties hereto.

 

[Signature page follows]

 

    7

     

    

 

IN WITNESS WHEREOF, the parties hereto have
executed this Agreement to be effective as of the date first set forth above.

 

	 	COMPANY:
	 	 
	 	FIRSTMARK HORIZON ACQUISITION CORP.
	 	 	 
	 	By:	 
	 	 	Name:
	 	 	Title:

 

	 	PURCHASER:
	 	 
	 	FirstMark
Horizon Sponsor LLC
	 	 	 
	 	By:	 
	 	 	Name:
	 	 	Title:

 

[Signature Page to Private Placement
Warrants Purchase Agreement]

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00314-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00314-of-00352.parquet"}]]