Exhibit 10.8


 


TETRAGON ACQUISITION CORPORATION I


 


399 Park Avenue, 22nd Floor


New York, NY 10022


 








	TFG Asset Management Sponsor LLC	March 19, 2021



 


399 Park Avenue, 22nd Floor


New York, NY 10022


 


RE: Securities
Subscription Agreement


 


Ladies and Gentlemen:


 


Tetragon Acquisition Corporation I, a Delaware
corporation (the “Company”), is pleased to accept the offer TFG Asset Management Sponsor LLC, a Delaware limited
liability company (the “Subscriber” or “you”), has made to purchase 14,375,000 of the Company’s
Class B common stock (the “Shares”), $0.0001 par value per share (the “Class B Common Stock”),
up to 1,875,000 Shares of which are subject to complete or partial forfeiture by you if the underwriters of the initial public
offering (“IPO”) of the Company, do not fully exercise their over-allotment option (the “Over-allotment
Option”). For the purposes of this Agreement, references to “Common Stock,” are to, collectively,
the Class B Common Stock and the Company’s Class A common stock, $0.0001 par value per share (the “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 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 (this “Agreement”) 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 below, 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 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 will be a legal, valid and binding agreement of Subscriber, enforceable against
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. 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.
Subscriber is capable of evaluating the merits and risks of its investment in the Company and has the capacity to protect its own
interests. Subscriber must bear the economic risk of this investment until the Securities are sold pursuant to: (i) an effective
registration statement under the Securities Act or (ii) an exemption from registration available with respect to such sale. Subscriber
is able to bear the economic risks of an investment in the Securities and to afford a complete loss of 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, Subscriber has relied solely on Subscriber’s
own knowledge and understanding of the Company and its business based upon Subscriber’s own due diligence investigation and
the information furnished pursuant to this paragraph. 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 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.


 






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2.1.6 Regulation D Offering.
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 to “accredited investors” within the meaning of Section
501(a) of Regulation D under the Securities Act or similar exemptions under applicable state law.


 


2.1.7 Investment
Purposes. The Subscriber is subscribing for and 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. Neither the Subscriber nor any of its officers, managers, employees, agents or members has either directly or indirectly,
including through a broker or finder (i) to its knowledge, engaged in any general solicitation, or (ii) published any general advertisement
in connection with the offer and sale of the Securities.


 


2.1.8 Restrictions
on Transfer; Shell Company. Subscriber understands the Securities are being offered in a transaction not involving a public
offering within the meaning of the Securities Act. Subscriber understands the Securities will be “restricted securities”
within the meaning of Rule 144(a)(3) under the Securities Act and 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. 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,
Subscriber may 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 offer, resell, pledge or otherwise transfer the Securities. 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 Securities until
one year following consummation of the initial business combination of the Company, 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 Subscriber in connection with the transactions contemplated by this Agreement.


 






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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.


 


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 and the Charter, the Securities
will be duly and validly issued, fully paid and nonassessable. Upon issuance in accordance with, and payment pursuant to, the terms
hereof and the Charter, 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, (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
General Solicitation. Neither the Company, nor any of its officers, directors, employees, agents or stockholders has either
directly or indirectly, including, through a broker or finder (i) engaged in any general solicitation, or (ii) published any general
advertisement in connection with the offer and sale of the Securities.


 


2.2.5 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.


 


2.2.6 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
forfeit any and all rights to such number of Shares (up to an aggregate of 1,875,000 Shares and pro rata based upon the percentage
of the Over-allotment Option exercised) such that immediately following such forfeiture, the Subscriber (and any such transferees)
will own an aggregate number of Shares (not including Shares issuable upon exercise of any warrants or any Common Stock purchased
by the Subscriber in the IPO or in the aftermarket) equal to 20% of the issued and outstanding Common Stock immediately following
the IPO.


 






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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 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 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
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 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.


 


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”)
to be dated on or prior to the closing date of the IPO by and between Subscriber and the Company, 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 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.
Subscriber acknowledges that the Securities will be subject to lock-up provisions (the “Lock-up”) contained
in the Insider Letter.


 






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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,
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 stock dividend, the declaration of a special 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 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 in connection with 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.


 


6.2 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.


 






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6.3 Entire Agreement.
This Agreement, together with the Insider Letter 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.


 


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 New York applicable to contracts wholly performed within the borders of such state, without giving effect to the conflict
of law principles thereof.


 


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.


 


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.


 






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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 hold 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 sections 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.


 


6.15 Construction.
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.


 






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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. 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 (such party, the “Indemnifying Party”) the other party (such party, the “Indemnified
Party”) and its respective officers, employees, and controlling persons to the fullest extent permitted by law from
and against any and all losses, damages, expenses (including reasonable attorneys’ fees and expenses) or other liabilities
resulting from or arising out of such party’s breach of any representation, warranty, covenant or agreement in this Agreement.
The foregoing indemnification rights apply so long as the action or failure to act by the Indemnified Party does not constitute
fraud, bad faith, willful misconduct or gross negligence. Notwithstanding any of the foregoing to the contrary, indemnification
protections will not be construed so as to relieve (or attempt to relieve) any Indemnified Party of any liability (including liability
under federal securities laws which, under certain circumstances, impose liability even on persons that act in good faith), to
the extent (but only to the extent) that such liability may not be waived, modified or limited under applicable law, but will
only be construed so as to effectuate the indemnification protections to the fullest extent permitted by law.


 


[Signature Page Follows]


 




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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,
	 	 
	 	TETRAGON ACQUISITION CORPORATION I
	 	 
	 	By:	/s/ Reade Griffith
	 		Name: 	Reade Griffith
	 		Title:	Authorized Officer


 


Accepted and agreed this 19th day of March, 2021


 


	TFG ASSET MANAGEMENT SPONSOR LLC	 
	 	 	 	 
	By:	/s/ Reade Griffith	 
	 	Name: 	Reade Griffith	 
	 	Title:	Authorized Person