Exhibit 10.5


 


PRIVATE PLACEMENT UNITS PURCHASE AGREEMENT


 


This PRIVATE PLACEMENT
UNITS PURCHASE AGREEMENT (this “Agreement”) is made as of the th day of March 2021, by and between B. Riley
Principal 250 Merger Corp., a Delaware corporation (the “Company”), and B. Riley Principal 250 Sponsor Co.,
LLC, a Delaware limited liability company (the “Subscriber”), each with a principal place of business at 299
Park Avenue, 21st Floor New York, New York 10171.


 


WHEREAS, the Company
desires to sell to Subscriber on a private placement basis (the “Offering”) an aggregate of 555,000 units (the
“Initial Units”) of the Company and up to an additional 45,000 units (the “Additional Units”
and, together with the Initial Units the “Units”) of the Company in the event that the underwriters’
over-allotment option (the “Over-Allotment Option”) in connection with the IPO (as defined below) is exercised
in full or in part, each Unit comprised of one share of Class A common stock of the Company, par value $0.0001 per share (“Common
Stock”), and one-third of one warrant (“Warrant”), for a purchase price of $5,550,000 (or $6,000,000
if the Over-Allotment Option is exercised in full), or $10.00 per Unit. The shares of Common Stock underlying the Warrants are
hereinafter referred to as the “Warrant Shares”. The shares of Common Stock underlying the Units (excluding
the Warrant Shares) are hereinafter referred to as the “Placement Shares.” The Warrants underlying the Units
are hereinafter referred to as the “Placement Warrants.” The Units, Placement Shares, Placement Warrants and
Warrant Shares, collectively, are hereinafter referred to as the “Securities.” Each whole Placement Warrant
is exercisable to purchase one share of Common Stock at an exercise price of $11.50 per share during the period commencing 30
days following the consummation of the Company’s initial business combination (the “Business Combination”),
as such term is defined in the registration statement in connection with the IPO, as amended at the time it becomes effective
(the “Registration Statement”), and expiring on the fifth anniversary of the consummation of the Business Combination;
and


 


WHEREAS, Subscriber
wishes to purchase 555,000 Units (or 600,000 Units if the Over-Allotment Option is exercised in full) for a purchase price of $5,550,000
(or $6,000,000 if the Over-Allotment Option is exercised in full) and the Company wishes to accept such subscription from Subscriber.


 


NOW, THEREFORE, in
consideration of the premises and the mutual covenants hereinafter set forth and other good and valuable consideration, the receipt
and sufficiency of which are hereby acknowledged, the Company and Subscriber hereby agree as follows:


 


		1.	Agreement to Subscribe



 


1.1       Purchase
and Issuance of the Units. Upon the terms and subject to the conditions of this Agreement, Subscriber hereby agrees to purchase
from the Company, and the Company hereby agrees to sell to Subscriber, on the Closing Date (as defined below) the Initial Units
in consideration of the payment of the Initial Purchase Price (as defined below). On the Closing Date, the Company shall deliver
(via book entry) to Subscriber the Securities purchased. Subscriber hereby agrees to purchase up to an additional 45,000 Additional
Units at $10.00 per Additional Unit for a purchase price of up to $450,000. The purchase and issuance of the Additional Units shall
occur only in the event that the Over-Allotment Option is exercised in full or in part. The total number of Additional Units to
be purchased hereunder shall be in the same proportion as the proportion of the Over-Allotment Option that is exercised. Each purchase
of Additional Units shall occur simultaneously with the consummation of any portion of the Over-Allotment Option.


 






     


     


    

 


1.2       Purchase
Price. As payment in full for the Initial Units being purchased under this Agreement, Subscriber shall pay an aggregate of $5,550,000
(the “Initial Purchase Price”) by wire transfer of immediately available funds or by such other method as may
be reasonably acceptable to the Company, 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 (“Continental”),
no later than one (1) business day prior to the date of effectiveness of the Registration Statement. As payment in full for the
Additional Units being purchased under this Agreement, Subscriber shall pay $10.00 per Additional Unit being purchased by wire
transfer of immediately available funds or by such other method as may be reasonably acceptable to the Company, to the Trust Account
at a financial institution to be chosen by the Company, maintained by Continental, one (1) business day prior to the Closing Date
of the Over-Allotment Option.


 


1.3       Closing.
The closing of the purchase and sale of the Initial Units shall take place simultaneously with the closing of the IPO and the closing
of the purchase and sale of Additional Units shall take place simultaneously with the closing of the Over-Allotment Option (each,
a “Closing Date”). The closing of the purchase and sale of the Units shall take place at the offices of White & Case LLP, 1221 Avenue of the Americas, New York, New York 10020, or such other place as may be agreed upon by the parties
hereto.


 


1.4       Termination.
This Agreement and each of the obligations of the undersigned shall be null and void and without effect if the IPO does not close
prior to December 31, 2021.


 


		2.	Representations and Warranties of Subscriber



 


Subscriber represents
and warrants to the Company that:


 


2.1       No
Government Recommendation or Approval. Subscriber understands that no federal or state agency has passed upon or made any recommendation
or endorsement of the Company or the Offering of the Securities.


 


2.2       Accredited
Investor. 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 that the sale contemplated
hereby is being made in reliance, among other things, on a private placement exemption to “accredited investors” under
the Securities Act and similar exemptions under state law.


 


2.3       Intent.
Subscriber is purchasing the Securities solely for investment purposes, for Subscriber’s own account (and/or for the account
or benefit of its members or affiliates, as permitted, pursuant to the terms of an agreement (the “Insider Letter”)
to be entered into with respect to the Securities between, among others, Subscriber and the Company, as described in the Registration
Statement), and not with a view to the distribution thereof and Subscriber has no present arrangement to sell the Securities to
or through any person or entity except as may be permitted under the Insider Letter. Subscriber shall not engage in hedging transactions
with regard to the Securities unless in compliance with the Securities Act.


 


2.4       Restrictions
on Transfer. Subscriber acknowledges and understands the Units are being offered in a transaction not involving a public offering
in the United States within the meaning of the Securities Act. The Securities have not been registered under the Securities Act
and, if in the future Subscriber decides to offer, resell, pledge or otherwise transfer the Securities, such Securities may be
offered, resold, pledged or otherwise transferred only (A) pursuant to an effective registration statement filed under the Securities
Act, (B) pursuant to an exemption from registration under Rule 144 promulgated under the Securities Act, if available, or (C) pursuant
to any other available exemption from the registration requirements of the Securities Act, and in each case in accordance with
any applicable securities laws of any state or any other jurisdiction. Notwithstanding the foregoing, Subscriber acknowledges and
understands the Securities are subject to transfer restrictions as described in Section 8 hereof. 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 with respect to such transfer. Absent
registration or another available exemption from registration, Subscriber agrees it will not resell the Securities (unless otherwise
permitted pursuant to the Insider Letter, as described in the Registration Statement). Subscriber further acknowledges that because
the Company is a shell company, Rule 144 may not be available to Subscriber for the resale of the Securities until the one-year
anniversary following consummation of the Business Combination of the Company, despite technical compliance with the requirements
of Rule 144 and the release or waiver of any contractual transfer restrictions.


 






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2.5       Sophisticated
Investor.


 


(i)       Subscriber
is sophisticated in financial matters and is able to evaluate the risks and benefits of the investment in the Securities.


 


(ii)       Subscriber
is aware that an investment in the Securities is highly speculative and subject to substantial risks because, among other things,
the Securities are subject to transfer restrictions and have not been registered under the Securities Act and therefore cannot
be sold unless subsequently registered under the Securities Act or an exemption from such registration is available. Subscriber
is able to bear the economic risk of its investment in the Securities for an indefinite period of time.


 


2.6       Independent
Investigation. Subscriber, in making the decision to purchase the Units, has relied upon an independent investigation of the Company
and has not relied upon any information or representations made by any third parties or upon any oral or written representations
or assurances from the Company, its officers, directors or employees or any other representatives or agents of the Company, other
than as set forth in this Agreement. Subscriber is familiar with the business, operations and financial condition of the Company
and has had an opportunity to ask questions of, and receive answers from the Company’s officers and directors concerning
the Company and the terms and conditions of the offering of the Units and has had full access to such other information concerning
the Company as Subscriber has requested. Subscriber confirms that all documents that it has requested have been made available
and that Subscriber has been supplied with all of the additional information concerning this investment which Subscriber has requested.


 


2.7       Organization
and Authority. Subscriber is duly organized, validly existing and in good standing under the laws of the State of Delaware and
it possesses all requisite power and authority necessary to carry out the transactions contemplated by this Agreement.


 


2.8       Authority.
This Agreement has been validly authorized, executed and delivered by Subscriber and is a valid and binding agreement enforceable
in accordance with its terms, subject to the general principles of equity and to bankruptcy or other laws affecting the enforcement
of creditors’ rights generally.


 


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


 


2.10       No
Legal Advice from Company. Subscriber acknowledges it has had the opportunity to review this Agreement and the transactions contemplated
by this Agreement and the other agreements entered into between the parties hereto with Subscriber’s own legal counsel and
investment and tax advisors. Except for any statements or representations of the Company made in this Agreement and the other agreements
entered into between the parties hereto, Subscriber is relying solely on such counsel and advisors and not on any statements or
representations of the Company or any of its representatives or agents for legal, tax or investment advice with respect to this
investment, the transactions contemplated by this Agreement or the securities laws of any jurisdiction.


 






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2.11       Reliance
on Representations and Warranties. Subscriber understands the Units are being offered and sold to Subscriber in reliance on exemptions
from the registration requirements under the Securities Act, and analogous provisions in the laws and regulations of various states,
and that the Company is relying upon the truth and accuracy of the representations, warranties, agreements, acknowledgments and
understandings of Subscriber set forth in this Agreement in order to determine the applicability of such provisions.


 


2.12       No
General Solicitation. Subscriber is not subscribing for the Units as a result of or subsequent to any general solicitation or general
advertising, including but not limited to any advertisement, article, notice or other communication published in any newspaper,
magazine, or similar media or broadcast over television or radio, or presented at any seminar or meeting or in a registration statement
with respect to the IPO filed with the Securities and Exchange Commission (the “SEC”).


 


2.13       Legend.
Subscriber acknowledges and agrees the certificates evidencing each of the Securities shall bear a restrictive legend (the “Legend”),
in form and substance substantially as set forth in Section 4 hereof.


 


		3.	Representations, Warranties and Covenants of the Company



 


The Company represents
and warrants to, and agrees with, Subscriber that:


 


3.1       Valid
Issuance of Capital Stock. The total number of shares of all classes of capital stock which the Company has authority to issue
is 100,000,000 shares of common stock, including 111,000,000 shares of Class A Common Stock and 10,000,000 shares of Class B common
stock, $0.0001 par value per share (“Class B Common Stock”), and 1,000,000 shares of preferred stock, $0.0001
par value per share (“Preferred Stock”). As of the date hereof, the Company has issued and outstanding 4,312,500
shares of Class B Common Stock (of which up to 562,500 shares are subject to forfeiture as described in the Registration Statement),
no shares of Class A Common Stock and no shares of Preferred Stock. All of the issued shares of capital stock of the Company have
been duly authorized, validly issued, and are fully paid and non-assessable.


 


3.2       Title
to Securities. Upon issuance in accordance with, and payment pursuant to, the terms hereof and that certain warrant agreement to
be entered into between the Company and Continental, as warrant agent (the “Warrant Agreement”), each of the
Units, Placement Shares, Placement Warrants and Warrant Shares will be duly and validly issued, fully paid and non-assessable.
On the date of issuance of the Units, the Warrant Shares shall have been reserved for issuance. Upon issuance in accordance with,
and payment pursuant to, the terms hereof and the Warrant Agreement, Subscriber will have or receive good title to the Units, Placement
Shares and Placement Warrants, free and clear of all liens, claims and encumbrances of any kind, other than (i) transfer restrictions
hereunder and pursuant to the Insider Letter and (ii) transfer restrictions under federal and state securities laws.


 


3.3       Organization
and Qualification. The Company is a corporation duly incorporated, validly existing and in good standing under the laws of the
State of Delaware and has the requisite corporate power to own its properties and assets and to carry on its business as now being
conducted.


 






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3.4       Authorization;
Enforcement. (i) The Company has the requisite corporate power and authority to enter into and perform its obligations under this
Agreement and to issue the Securities in accordance with the terms hereof, (ii) the execution, delivery and performance of this
Agreement by the Company and the consummation by it of the transactions contemplated hereby have been duly authorized by all necessary
corporate action, and no further consent or authorization of the Company or its Board of Directors or stockholders is required,
(iii) this Agreement constitutes valid and binding obligations of the Company enforceable against the Company in accordance with
its terms, except as such enforceability may be limited by applicable bankruptcy, insolvency, fraudulent conveyance, moratorium,
reorganization, or similar laws relating to, or affecting generally the enforcement of, creditors’ rights and remedies or
by equitable principles of general application and except as enforcement of rights to indemnity and contribution may be limited
by federal and state securities laws or principles of public policy, (iv) the Units, when issued and delivered in the manner set
forth herein, will constitute valid and binding obligations of the Company enforceable against the Company in accordance with their
terms, except as such enforceability may be limited by applicable bankruptcy, insolvency, fraudulent conveyance, moratorium, reorganization,
or similar laws relating to, or affecting generally the enforcement of, creditors’ rights and remedies or by equitable principles
of general application and except as enforcement of rights to indemnity and contribution may be limited by federal and state securities
laws or principles of public policy and (v) the Placement Warrants, when issued and delivered in the manner set forth herein, will
constitute valid and binding obligations of the Company enforceable against the Company in accordance with their terms, except
as such enforceability may be limited by applicable bankruptcy, insolvency, fraudulent conveyance, moratorium, reorganization,
or similar laws relating to, or affecting generally the enforcement of, creditors’ rights and remedies or by equitable principles
of general application and except as enforcement of rights to indemnity and contribution may be limited by federal and state securities
laws or principles of public policy.


 


3.5       No
Conflicts. The execution, delivery and performance of this Agreement and the consummation by the Company of the transactions contemplated
hereby do not (i) result in a violation of the Company’s certificate of incorporation or by-laws, (ii) conflict with, or
constitute a default under any agreement or instrument to which the Company is a party or (iii) any law statute, rule or regulation
to which the Company is subject or any agreement, order, judgment or decree to which the Company is subject. Other than any SEC
or state securities filings which may be required to be made by the Company subsequent to the closing of the IPO, and any registration
statement which may be filed pursuant thereto, the Company is not required under federal, state or local law, rule or regulation
to obtain any consent, authorization or order of, or make any filing or registration with, any court or governmental agency or
self-regulatory entity in order for it to perform any of its obligations under this Agreement or issue the Units, Placement Shares,
Placement Warrants or the Warrant Shares in accordance with the terms hereof.


 


		4.	Legends



 


4.1       Legend.
The Company will issue the Units, Placement Shares and Placement Warrants, and when issued, the Warrant Shares, purchased by Subscriber
in the name of Subscriber. The Securities will bear the following Legend and appropriate “stop transfer” instructions:


 


“THE SECURITIES
REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), 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 THE SECURITIES ACT OR SUCH LAWS OR AN EXEMPTION FROM REGISTRATION
UNDER THE SECURITIES ACT AND SUCH LAWS WHICH, IN THE OPINION OF COUNSEL FOR THIS CORPORATION, IS AVAILABLE.”


 


“THE SECURITIES
REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO LOCKUP PURSUANT TO AN INSIDER LETTER BETWEEN, AMONG OTHERS, B. RILEY PRINCIPAL 250
MERGER CORP. AND B. RILEY PRINCIPAL 250 SPONSOR CO., LLC AND MAY ONLY BE OFFERED, SOLD, TRANSFERRED, PLEDGED OR OTHERWISE DISPOSED
DURING THE TERM OF THE LOCKUP PURSUANT TO THE TERMS SET FORTH IN THE INSIDER LETTER.”


 






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4.2       Subscriber’s
Compliance. Nothing in this Section 4 shall affect in any way Subscriber’s obligations and agreements to comply with all
applicable securities laws upon resale of the Securities.


 


4.3       Company’s
Refusal to Register Transfer of the Securities. The Company shall refuse to register any transfer of the Securities, if in the
sole judgment of the Company such purported transfer would not be made (i) pursuant to an effective registration statement filed
under the Securities Act, or pursuant to an available exemption from the registration requirements of the Securities Act and (ii)
in compliance herewith and with the Insider Letter.


 


4.4       Registration
Rights. Subscriber will be entitled to certain registration rights which will be governed by a registration rights agreement (“Registration
Rights Agreement”) to be entered into between, among others, Subscriber and the Company, on or prior to the effective
date of the Registration Statement.


 


		5.	Waiver of Liquidation Distributions.



 


In connection with
the Securities purchased pursuant to this Agreement, Subscriber hereby waives any and all right, title, interest or claim of any
kind in or to any distributions of the amounts in the Trust Account with respect to the Securities, whether (i) in connection with
the exercise of redemption rights if the Company consummates the Business Combination, (ii) in connection with any tender offer
conducted by the Company prior to a Business Combination, (iii) upon the Company’s redemption of shares of Common Stock sold
in the Company’s IPO upon the Company’s failure to timely complete the Business Combination or (iv) 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 redeem 100% of the Company’s public shares if the Company does
not timely complete the Business Combination or (B) with respect to any other provision relating to stockholders’ rights
or pre-Business Combination activity. In the event Subscriber purchases shares of Common Stock in the IPO or in the aftermarket,
any additional shares so purchased shall be eligible to receive the redemption value of such shares of Common Stock upon the same
terms offered to all other purchasers of Common Stock in the IPO in the event the Company fails to consummate the Business Combination.


 


		6.	Terms of Placement Warrants.



 


6.1       Terms.
Each Placement Warrant shall have the terms set forth in the Warrant Agreement.


 


6.2       Failure
to Consummate Business Combination. The Placement Warrants shall be terminated upon the dissolution of the Company or in the event
that the Company does not consummate the Business Combination within 24 months from the consummation of the IPO, unless otherwise
extended by the Company.


 


6.3       Termination
of Rights as Holder. If the Placement Warrants are terminated in accordance with Section 6.1, then after such time Subscriber (or
its successor in interest) shall no longer have any rights as a holder of such Placement Warrants and the Company shall take such
action as is appropriate to cancel such Placement Warrants. Subscriber hereby irrevocably grants the Company a limited power of
attorney for the purpose of effectuating the foregoing and agrees to take any and all measures reasonably requested by the Company
necessary to effect the foregoing.


 






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		7.	Rescission Right Waiver and Indemnification.



 


7.1       Subscriber
understands and acknowledges an exemption from the registration requirements of the Securities Act requires there be no general
solicitation of purchasers of the Units. In this regard, if the IPO were deemed to be a general solicitation with respect to the
Units, the offer and sale of such Units may not be exempt from registration and, if not, Subscriber may have a right to rescind
its purchase of the Units. In order to facilitate the completion of the Offering and in order to protect the Company, its stockholders
and the amounts in the Trust Account from claims that may adversely affect the Company or the interests of its stockholders, Subscriber
hereby agrees to waive, to the maximum extent permitted by applicable law, any claims, right to sue or rights in law or arbitration,
as the case may be, to seek rescission of its purchase of the Units. Subscriber acknowledges and agrees this waiver is being made
in order to induce the Company to sell the Units to Subscriber. Subscriber agrees the foregoing waiver of rescission rights shall
apply to any and all known or unknown actions, causes of action, suits, claims or proceedings (collectively, “Claims”)
and related losses, costs, penalties, fees, liabilities and damages, whether compensatory, consequential or exemplary, and expenses
in connection therewith, including reasonable attorneys’ and expert witness fees and disbursements and all other expenses
reasonably incurred in investigating, preparing or defending against any Claims, whether pending or threatened, in connection with
any present or future actual or asserted right to rescind the purchase of the Units hereunder or relating to the purchase of the
Units and the transactions contemplated hereby.


 


7.2       Subscriber
agrees not to seek recourse against the Trust Account for any reason whatsoever in connection with its purchase of the Units or
any Claim that may arise now or in the future.


 


7.3       Subscriber
acknowledges and agrees that the stockholders of the Company are and shall be third-party beneficiaries of this Section 7.


 


7.4       Subscriber
agrees that to the extent any waiver of rights under this Section 7 is ineffective as a matter of law, Subscriber has offered such
waiver for the benefit of the Company as an equitable right that shall survive any statutory disqualification or bar that applies
to a legal right. Subscriber acknowledges the receipt and sufficiency of consideration received from the Company hereunder in this
regard.


 


		8.	Terms of the Units and Placement Warrants



 


8.1       The
Units and their component parts are substantially identical to the units to be offered in the IPO except that: (i) the Units and
component parts will be subject to transfer restrictions, except in limited circumstances, until 30 days following the consummation
of the Business Combination, (ii) the Placement Warrants will be non-redeemable so long as they are held by Subscriber (or any
of its permitted transferees), and may be exercisable on a “cashless” basis if held by Subscriber or its permitted
transferees, as further described in the Warrant Agreement, and (iii) the Units and component parts 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 (i) and they are registered pursuant to the Registration Rights Agreement to be signed
on or before the date of the Prospectus or an exemption from registration is available, and the restrictions described above in
clause (i) has expired. Additionally, the Subscriber acknowledges and agrees that the Units and their component parts will be deemed
underwriting compensation by the Financial Industry Regulatory Authority (“FINRA”) and, pursuant to FINRA Rule
5110(g)(1), may not be sold during the offering, or transferred, assigned, pledged or hypothecated or be the subject of any hedging,
short sale, derivative, put or call transaction that would result in the economic disposition of the securities for a period of
180 days immediately following the date of effectiveness or commencement of sales in the IPO, except as provided in FINRA Rule
5110(g)(2).


 


8.2       Subscriber
agrees to vote the Placement Shares in accordance with the terms of the Insider Letter and as otherwise described in the Registration
Statement.


 


		9.	Governing Law; Jurisdiction; Waiver of Jury Trial



 


This Agreement shall
be governed by and construed in accordance with the laws of the State of New York for agreements made and to be wholly performed
within such state, without regards to the conflicts of laws principles thereof. Any suit brought by either party shall be brought
in the state or federal courts sitting in New York County in the State of New York. The parties hereto hereby waive any right to
a jury trial in connection with any litigation pursuant to this Agreement and the transactions contemplated hereby.


 






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		10.	Assignment; Entire Agreement; Amendment



 


10.1       Assignment.
Neither this Agreement nor any rights hereunder may be assigned, in whole or in part, by any party to any other person without
the prior written consent of the other party hereto except that Subscriber may assign this Agreement, or any of its rights hereunder,
to a person agreeing to be bound by the terms hereof, including the waiver contained in Section 7 hereof.


 


10.2       Entire
Agreement. This Agreement sets forth the entire agreement and understanding between the parties as to the subject matter thereof
and merges and supersedes all prior discussions, agreements and understandings of any and every nature among them with respect
to such subject matter.


 


10.3       Amendment.
Except as expressly provided in this Agreement, neither this Agreement nor any term hereof may be amended, waived, discharged or
terminated other than by a written instrument signed by the party against whom enforcement of any such amendment, waiver, discharge
or termination is sought.


 


10.4       Binding
upon Successors. This Agreement shall be binding upon and inure to the benefit of the parties hereto and to their respective successors
and permitted assigns.


 


		11.	Notices



 


11.1       Notices.
Unless otherwise provided herein, any notice or other communication to a party hereunder shall be sufficiently given if in writing
and personally delivered or sent by facsimile or other electronic transmission with copy sent in another manner herein provided
or sent by courier (which for all purposes of this Agreement shall include Federal Express or other recognized overnight courier)
or mailed to said party by certified mail, return receipt requested, at its address provided for herein or such other address as
either may designate for itself in such notice to the other. Communications shall be deemed to have been received when delivered
personally, on the scheduled arrival date when sent by next day or 2nd-day courier service, or if sent by facsimile upon receipt
of confirmation of transmittal or, if sent by mail, then three days after deposit in the mail. If given by electronic transmission,
such notice shall be deemed to be delivered when directed to an electronic mail address at which such party has consented to receive
notice.


 


		12.	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 by e-mail
delivery of a “pdf” format data file, 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 facsimile or “.pdf” signature
page were an original thereof.


 


		13.	Survival; Severability



 


13.1       Survival.
The representations, warranties, covenants and agreements of the parties hereto shall survive the Closing.


 


13.2       Severability.
In the event that any provision of this Agreement becomes or is declared by a court of competent jurisdiction to be illegal, unenforceable
or void, this Agreement shall continue in full force and effect without said provision; provided that no such severability shall
be effective if it materially changes the economic benefit of this Agreement to any party.


 


		14.	Headings.



 


The titles and subtitles
used in this Agreement are used for convenience only and are not to be considered in construing or interpreting this Agreement.


 


[Signature Page Follows]


 




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


 


	 	B. RILEY PRINCIPAL 250 MERGER CORP.
	 	 	 
	 	By: 	 
	 	 	Name:  	Daniel Shribman
	 	 	Title:	Chief Executive and Chief Financial Officer


 


	 	B. RILEY PRINCIPAL 250 SPONSOR CO., LLC
	 	 	 
	 	By:	 
	 	 	 
	 	By: 	 
	 	 	Name: 	                
	 	 	Title:	 


 


[Signature Page to Private Placement
Units Subscription Agreement]


 


 


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