Exhibit
4.3


  


THESE
SECURITIES HAVE NOT BEEN REGISTERED WITH THE SECURITIES AND EXCHANGE COMMISSION OR THE SECURITIES COMMISSION OF ANY STATE IN RELIANCE
UPON AN EXEMPTION FROM REGISTRATION UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "SECURITIES ACT"), AND,
ACCORDINGLY, MAY NOT BE OFFERED OR SOLD EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT OR PURSUANT
TO AN AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN
ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS AS EVIDENCED BY A LEGAL OPINION OF COUNSEL TO THE TRANSFEROR TO SUCH EFFECT,
THE SUBSTANCE OF WHICH SHALL BE REASONABLY ACCEPTABLE TO THE COMPANY.


 


THE
REGISTERED HOLDER OF THIS PURCHASE WARRANT BY ITS ACCEPTANCE HEREOF, AGREES THAT IT WILL NOT SELL, TRANSFER OR ASSIGN THIS PURCHASE
WARRANT EXCEPT AS HEREIN PROVIDED AND THE REGISTERED HOLDER OF THIS PURCHASE WARRANT AGREES THAT IT WILL NOT SELL, TRANSFER, ASSIGN,
PLEDGE OR HYPOTHECATE THIS PURCHASE WARRANT FOR A PERIOD OF ONE HUNDRED EIGHTY DAYS FOLLOWING THE EFFECTIVE DATE (DEFINED BELOW)
TO ANYONE OTHER THAN (I) KINGSWOOD CAPITAL MARKETS, DIVISION OF BENCHMARK INVESTMENTS, INC. OR AN UNDERWRITER OR A SELECTED DEALER
IN CONNECTION WITH THE OFFERING, OR (II) A BONA FIDE OFFICER OR PARTNER OF KINGSWOOD CAPITAL MARKETS, DIVISION OF BENCHMARK INVESTMENTS,
INC. OR OF ANY SUCH UNDERWRITER OR SELECTED DEALER.


 


THIS
PURCHASE WARRANT IS NOT EXERCISABLE PRIOR TO AUGUST 11, 2021. VOID AFTER 5:00 P.M., EASTERN TIME, FEBRUARY 11, 2026.


 


COMMON
STOCK PURCHASE WARRANT


 


For
the Purchase of 106,400 Shares of Class A Common Stock


of


LONGEVERON
INC.


 


1. Purchase
Warrant. THIS CERTIFIES THAT, in consideration of funds duly paid by or on behalf of Kingswood Capital Markets, division of
Benchmark Investments, Inc. (“Holder”), as registered owner of this Purchase Warrant, Longeveron Inc., a Delaware
corporation (the “Company”), Holder is entitled, at any time or from time to time from August 11, 2021 (the
“Commencement Date”), and at or before 5:00 p.m., Eastern time, February
11, 2026 (the ”Expiration Date”), but not thereafter, to subscribe for, purchase and receive, in
whole or in part, up to 106,400 shares of Class A common stock of the Company, par value $0.001 per share (the “Shares”),
subject to adjustment as provided in Section 6 hereof. If the Expiration Date is a day on which banking institutions are authorized
by law to close, then this Purchase Warrant may be exercised on the next succeeding day which is not such a day in accordance
with the terms herein. This Purchase Warrant is initially exercisable at $12.00 per Share; provided, however, that
upon the occurrence of any of the events specified in Section 6 hereof, the rights granted by this Purchase Warrant, including
the exercise price per Share and the number of Shares to be received upon such exercise, shall be adjusted as therein specified.
The term “Exercise Price” shall mean the initial exercise price or the adjusted exercise price, depending on
the context. The term “Effective Date” shall mean February 11, 2021, the date on which the Registration Statement
on Form S-1 (File No. 333-252234) of the Company was declared effective by the Securities and Exchange Commission.


 






     


     


    

 


2.  Exercise.


 





2.1 Exercise
Form. In order to exercise this Purchase Warrant, the exercise form attached hereto must be duly executed and completed and
delivered to the Company, together with this Purchase Warrant and payment of the Exercise Price for the Shares being purchased
payable in cash by wire transfer of immediately available funds to an account designated by the Company or by certified check
or official bank check. If the subscription rights represented hereby shall not be exercised at or before 5:00 p.m., Eastern time,
on the Expiration Date, this Purchase Warrant shall become and be void without further force or effect, and all rights represented
hereby shall cease and expire.


 


2.2 Cashless
Exercise.  If at any time after the Commencement Date there is no effective registration statement registering, or no
current prospectus available for, the resale of the Shares by the Holder, then in lieu of exercising this Purchase Warrant by
payment of cash or check payable to the order of the Company pursuant to Section 2.1 above, Holder may elect to receive the number
of Shares equal to the value of this Purchase Warrant (or the portion thereof being exercised), by surrender of this Purchase
Warrant to the Company, together with the exercise form attached hereto, in which event the Company shall issue to Holder, Shares
in accordance with the following formula:


 


	X	=	Y(A-B)	 
	A	 



 


	Where,	 	 	 
	 	X	=	The number of Shares to be issued to Holder;
	 	Y	=	The number of Shares for which the Purchase Warrant is being exercised;
	 	A	=	The fair market value of one Share; and
	 	B	=	The Exercise Price.



 


For
purposes of this Section 2.2, the fair market value of a Share is defined as follows:


 




		(i)	if
                                         the Company’s Class A common stock is traded on a securities exchange, the value
                                         shall be deemed to be the closing price on such exchange immediately prior to the exercise
                                         form being submitted in connection with the exercise of the Purchase Warrant;



 


		(ii)	if
                                         the Company’s Class A common stock is actively traded over-the-counter, the value
                                         shall be deemed to be the closing bid price immediately prior to the exercise form being
                                         submitted in connection with the exercise of the Purchase Warrant; or



 


		(iii)	if
                                         there is no active public market, the value shall be the fair market value thereof, as
                                         determined in good faith by the Company’s Board of Directors.



 


2.3
 Legend. Each certificate for the securities purchased under this
Purchase Warrant shall bear a legend as follows unless such securities have been registered under the Securities Act of 1933,
as amended (the “Securities Act”):


 


“THE
SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES
ACT”), OR APPLICABLE STATE LAW. NEITHER THE SECURITIES NOR ANY INTEREST THEREIN MAY BE OFFERED FOR SALE, SOLD OR OTHERWISE
TRANSFERRED EXCEPT PURSUANT TO AN EFFECTIVE REGISTRATION STATEMENT UNDER THE SECURITIES ACT, OR PURSUANT TO AN EXEMPTION FROM
REGISTRATION UNDER THE SECURITIES ACT AND APPLICABLE STATE LAW WHICH, IN THE OPINION OF COUNSEL TO THE COMPANY, IS AVAILABLE.”


 




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3.  Transfer.


 


3.1 General
Restrictions. The registered Holder of this Purchase Warrant agrees by his, her or its acceptance hereof, that such Holder
will not: (a) sell, transfer, assign, pledge or hypothecate this Purchase Warrant for a period of one hundred eighty (180) days
following the Effective Date to anyone other than: (i) Kingswood Capital Markets, division of Benchmark Investments, Inc. (“Kingswood”)
or an underwriter or a selected dealer participating in the Offering, or (ii) a bona fide officer or partner of Kingswood or of
any such underwriter or selected dealer, in each case in accordance with FINRA Conduct Rule 5110(e)(1), or (b) cause this Purchase
Warrant or the securities issuable hereunder to be the subject of any hedging, short sale, derivative, put or call transaction
that would result in the effective economic disposition of this Purchase Warrant or the securities hereunder, except as provided
for in FINRA Rule 5110(e)(2). On and after 180 days after the Effective Date, transfers to others may be made subject to compliance
with or exemptions from applicable securities laws. In order to make any permitted assignment, the Holder must deliver to the
Company the assignment form attached hereto duly executed and completed, together with the Purchase Warrant and payment of all
transfer taxes, if any, payable in connection therewith. The Company shall within five (5) business days transfer this Purchase
Warrant on the books of the Company and shall execute and deliver a new Purchase Warrant or Purchase Warrants of like tenor to
the appropriate assignee(s) expressly evidencing the right to purchase the aggregate number of Shares purchasable hereunder or
such portion of such number as shall be contemplated by any such assignment.


 


3.2
 Restrictions Imposed by the Securities Act. The securities evidenced
by this Purchase Warrant shall not be transferred unless and until: (i) the Company has received the opinion of counsel for the
Holder that the securities may be transferred pursuant to an exemption from registration under the Securities Act and applicable
state securities laws, the availability of which is established to the reasonable satisfaction of the Company (the Company hereby
agreeing that the opinion of Nelson Mullins Riley & Scarborough LLP shall
be deemed satisfactory evidence of the availability of an exemption).


 


3.3  Ownership
of Warrants The Company may treat the registered holder of this Warrant in the books
of the Company as the owner and holder thereof for all purposes, notwithstanding any notice to the contrary, except that, if and
when any Warrant is properly assigned in blank, the Company may (but shall not be obligated to) treat the bearer thereof as the
owner of such Warrant for all purposes, notwithstanding any notice to the contrary. 


 


4.  Registration
Rights.


 


4.1 Demand
Registration.


 


4.1.1  Grant
of Right. Subject to the further requirements of this subsection 4.4.1, the Company, upon written demand (a “Demand
Notice”) of the Holders of at least 51% of the Purchase Warrants and/or the underlying Shares, agrees to register, on
one occasion, all or any portion of the Shares underlying the Purchase Warrants (excluding any Shares which have been transferred
and the subsequent disposition thereof no longer requires registration or qualification
under the Securities Act or any similar state law then in force) (collectively, the “Registrable Securities”).
For the purpose of this Section 4, the term “Registrable Securities” shall not include Shares that
have been transferred and the subsequent disposition thereof no longer requires registration
or qualification under the Securities Act or any similar state law then in force. On such occasion, the Company will file
a registration statement with the Commission covering the Registrable Securities within sixty (60) days after receipt of a Demand
Notice and use its reasonable best efforts to have the registration statement declared effective promptly thereafter, subject
to compliance with review by the Commission; provided, however, that the Company shall not be required to comply
with a Demand Notice if (a) the Registration Statement is still in effect or (b) the Company has filed a registration statement
with respect to which the Holder is entitled to piggyback registration rights pursuant to Section 4.2 hereof and either: (i) the
Holder has elected to participate in the offering covered by such registration statement or (ii) if such registration statement
relates to an underwritten primary offering of securities of the Company, until the offering covered by such registration statement
has been withdrawn or until thirty (30) days after such offering is consummated. The demand for registration may be made on one
occasion during the three (3) year period beginning on the Commencement Date. The Company covenants and agrees to give written
notice of its receipt of any Demand Notice by any Holders to all other registered Holders of the Purchase Warrants and/or the
Registrable Securities within ten (10) days after the date of the receipt of any such Demand Notice.


 






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4.1.2
 Terms. The Company shall bear all fees and expenses attendant to the registration of
the Registrable Securities pursuant to Section 4.1.1, but the Holders shall pay any and all underwriting commissions and the expenses
of any legal counsel selected by the Holders to represent them in connection with the sale of the Registrable Securities. The
Company agrees to use commercially reasonable efforts to cause the filing required herein to become effective promptly and to
qualify or register the Registrable Securities in such states as are reasonably requested by the Holders; provided, however,
that in no event shall the Company be required to register the Registrable Securities in a State in which such registration would
cause: (i) the Company to be obligated to register or license to do business in such State or submit to general service of process
in such State, or (ii) the principal stockholders of the Company to be obligated to escrow their shares of capital stock of the
Company. The Company shall cause any registration statement filed pursuant to the demand right granted under Section 4.1.1 to
remain effective for a period of at least twelve (12) consecutive months after the date that the Holders of the Registrable Securities
covered by such registration statement are first given the opportunity to sell all of such securities. The Holders shall only
use the prospectuses provided by the Company to sell the shares covered by such registration statement, and will immediately cease
to use any prospectus furnished by the Company if the Company advises the Holder that such prospectus may no longer be used due
to a material misstatement or omission. Notwithstanding the provisions of this Section 4.1.2, the Holder shall be entitled to
a demand registration under this Section 4.1.2 on only one (1) occasion and such demand registration right shall terminate on
the third anniversary of the Commencement Date.


 


4.2 “Piggy-Back”
Registration.


 


4.2.1  Grant
of Right. In addition to the demand right of registration described in Section 4.1 hereof, the Holder shall have the right,
for a period of no more than seven (7) years from the Effective Date in accordance with FINRA Rule 5110(g)(8)(D), to include the
Registrable Securities as part of any other registration of securities filed by the Company (other than in connection with a transaction
contemplated by Rule 145(a) promulgated under the Securities Act or pursuant to Form S-8 or any equivalent form); provided,
however, that if, solely in connection with any primary underwritten public offering for the account of the Company, the
managing underwriter(s) thereof shall, in its reasonable discretion, impose a limitation on the number of shares of Class A common
stock which may be included in the registration statement because, in such underwriter(s)’ judgment, marketing or other
factors dictate such limitation is necessary to facilitate public distribution, then the Company shall be obligated to include
in such registration statement only such limited portion of the Registrable Securities with respect to which the Holder requested
inclusion hereunder as the underwriter shall reasonably permit. Any exclusion of Registrable Securities shall be made pro rata
among the Holders seeking to include Registrable Securities in proportion to the number of Registrable Securities sought to be
included by such Holders; provided, however, that the Company shall not exclude any Registrable Securities unless
the Company has first excluded all outstanding securities, the holders of which are not entitled to inclusion of such securities
in such registration statement or are not entitled to pro rata inclusion with the Registrable Securities.


 


4.2.2
 Terms. The Company shall bear all fees and expenses attendant to registering the Registrable
Securities pursuant to Section 4.2.1 hereof, but the Holders shall pay any and all underwriting commissions and fees and the expenses
of any legal counsel selected by the Holders to represent them in connection with the sale of the Registrable Securities. In the
event of such a proposed registration, the Company shall furnish the then Holders of outstanding Registrable Securities with not
less than thirty (30) days’ written notice prior to the anticipated effective date of such registration statement. Such
notice to the Holders shall continue to be given for each registration statement filed by the Company until such time as all of
the Registrable Securities have been sold by the Holder. The holders of the Registrable Securities shall exercise the “piggy-back”
rights provided for herein by giving written notice within ten (10) days of the receipt of the Company’s notice of the anticipated
effective date of the registration statement. Except as otherwise provided in this Purchase Warrant, there shall be no limit on
the number of times the Holder may request registration under this Section 4.2.2; provided, however, that such registration
rights shall terminate on the sixth anniversary of the Commencement Date.


 


4.3 General
Terms.


 


4.3.1
 Indemnification. The Company shall indemnify the Holders of the Registrable Securities to be sold
pursuant to any registration statement hereunder and each person, if any, who controls such Holders within the meaning of Section
15 of the Securities Act or Section 20(a) of the Securities Exchange Act of 1934, as amended (“Exchange Act”),
against all loss, claim, damage, expense or liability (including all reasonable attorneys’ fees and other expenses reasonably
incurred in investigating, preparing or defending against any claim whatsoever) to which any of them may become subject under
the Securities Act, the Exchange Act or otherwise, arising from such registration statement but only to the same extent and with
the same effect as the provisions pursuant to which the Company has agreed to indemnify the Underwriters contained in Section
5.1 of the Underwriting Agreement between the Underwriters and the Company, dated as of February 11, 2021. The Holders of the
Registrable Securities to be sold pursuant to such registration statement, and their successors and assigns, shall severally,
and not jointly, indemnify the Company, against all loss, claim, damage, expense or liability (including all reasonable attorneys’
fees and other expenses reasonably incurred in investigating, preparing or defending against any claim whatsoever) to which they
may become subject under the Securities Act, the Exchange Act or otherwise, arising from information furnished by or on behalf
of such Holders, or their successors or assigns, in writing, for specific inclusion in such registration statement to the same
extent and with the same effect as the provisions contained in Section 5.2 of the Underwriting Agreement pursuant to which the
Underwriters have agreed to indemnify the Company.


 




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4.3.2   Exercise
of Purchase Warrants. Nothing contained in this Purchase Warrant shall be construed as requiring the Holders to exercise their
Purchase Warrants prior to or after the initial filing of any registration statement or the effectiveness thereof.


 


4.3.3
 Documents Delivered to Holders. In the sale by the Holders is an underwritten offering,
the Company shall furnish to Holder participating in such offering and each underwriter of any such offering, a signed counterpart,
addressed to such Holder or underwriter, of: (i) an opinion of counsel to the Company dated the date of the closing under any
underwriting agreement related thereto), and (ii) a “cold comfort” letter dated the date of the closing under the
underwriting agreement) signed by the independent registered public accounting firm which has issued a report on the Company’s
financial statements included in such registration statement, in each case covering substantially the same matters with respect
to such registration statement (and the prospectus included therein) and, in the case of such accountants’ letter, with
respect to events subsequent to the date of such financial statements, as are customarily covered in opinions of issuer’s
counsel and in accountants’ letters delivered to underwriters in underwritten public offerings of securities. The Company
shall also deliver promptly to each Holder participating in the offering requesting the correspondence and memoranda described
below and to the managing underwriter, if any, copies of all correspondence between the Commission and the Company, its counsel
or auditors and all memoranda relating to discussions with the Commission or its staff with respect to the registration statement
and permit each Holder and underwriter to do such investigation, upon reasonable advance notice, with respect to information contained
in or omitted from the registration statement as it deems reasonably necessary to comply with applicable securities laws or rules
of FINRA. Such investigation shall include access to books, records and properties and opportunities to discuss the business of
the Company with its officers and independent auditors, all to such reasonable extent and at such reasonable times as any such
Holder shall reasonably request.


 


4.3.4  Underwriting
Agreement. The Company shall enter into an underwriting agreement with the managing underwriter(s), if any, selected by any
Holders whose Registrable Securities are being registered pursuant to this Section 4, which managing underwriter shall be reasonably
satisfactory to the Company. Such agreement shall be reasonably satisfactory in form and substance to the Company, each Holder
and such managing underwriters, and shall contain such representations, warranties and covenants by the Company and such other
terms as are customarily contained in agreements of that type used by the managing underwriter. The Holders shall be parties to
any underwriting agreement relating to an underwritten sale of their Registrable Securities and may, at their option, require
that any or all the representations, warranties and covenants of the Company to or for the benefit of such underwriters shall
also be made to and for the benefit of such Holders. Such Holders shall not be required to make any representations or warranties
to or agreements with the Company or the underwriters except as they may relate to such Holders, their Shares and their intended
methods of distribution.


 


4.3.5
 Documents to be Delivered by Holders. Each of the Holders participating in any of the
foregoing offerings shall furnish to the Company a completed and executed questionnaire provided by the Company requesting information
customarily sought of selling security holders.


 


4.3.6
 Damages. Should the registration or the effectiveness thereof required by Sections 4.1 and
4.2 hereof be delayed by the Company or the Company otherwise fails to comply with such provisions, the Holders shall, in addition
to any other legal or other relief available to the Holders, be entitled to obtain specific performance or other equitable (including
injunctive) relief against the threatened breach of such provisions or the continuation of any such breach, without the necessity
of proving actual damages and without the necessity of posting bond or other security.


 




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5.  New
Purchase Warrants to be Issued.


 


5.1 Partial
Exercise or Transfer. Subject to the restrictions in Section 3 hereof, this Purchase Warrant may be exercised or assigned
in whole or in part. In the event of the exercise or assignment hereof in part only, upon surrender of this Purchase Warrant for
cancellation, together with the duly executed exercise or assignment form and funds sufficient to pay any Exercise Price and/or
transfer tax if exercised pursuant to Section 2.1 hereto, the Company shall cause to be delivered to the Holder without charge
a new Purchase Warrant of like tenor to this Purchase Warrant in the name of the Holder evidencing the right of the Holder to
purchase the number of Shares purchasable hereunder as to which this Purchase Warrant has not been exercised or assigned.


 


5.2
 Lost Certificate. Upon receipt by the Company of evidence satisfactory
to it of the loss, theft, destruction or mutilation of this Purchase Warrant and of reasonably satisfactory indemnification or
the posting of a bond, the Company shall execute and deliver a new Purchase Warrant of like tenor and date. Any such new Purchase
Warrant executed and delivered as a result of such loss, theft, mutilation or destruction shall constitute a substitute contractual
obligation on the part of the Company.


 


6.  Adjustments.


 


6.1 Adjustments
to Exercise Price and Number of Securities. The Exercise Price and the number of Shares underlying the Purchase Warrant shall
be subject to adjustment from time to time as hereinafter set forth:


 


6.1.1  Share
Dividends; Split Ups. If, after the date hereof, and subject to the provisions of Section 6.3 below, the number of outstanding
Shares is increased by a stock dividend payable in Shares or by a split up of Shares or other similar event, then, on the effective
day thereof, the number of Shares purchasable hereunder shall be increased in proportion to such increase in outstanding Shares,
and the Exercise Price shall be proportionately decreased.


 


6.1.2
 Aggregation of Shares. If, after the date hereof, and subject to the provisions of
Section 6.3 below, the number of outstanding Shares is decreased by a consolidation, combination or reclassification of Shares
or other similar event, then, on the effective date thereof, the number of Shares purchasable hereunder shall be decreased in
proportion to such decrease in outstanding Shares, and the Exercise Price shall be proportionately increased.


 


6.1.3
 Replacement of Securities upon Reorganization, etc. In case of any reclassification
or reorganization of the outstanding Shares other than a change covered by Section 6.1.1 or 6.1.2 hereof or that solely affects
the par value of such Shares, or in the case of any share reconstruction or amalgamation or consolidation of the Company with
or into another corporation (other than a consolidation or share reconstruction or amalgamation in which the Company is the continuing
corporation and that does not result in any reclassification or reorganization of the outstanding Shares), or in the case of any
sale or conveyance to another corporation or entity of the property of the Company as an entirety or substantially as an entirety
in connection with which the Company is dissolved, the Holder of this Purchase Warrant shall have the right thereafter (until
the expiration of the right of exercise of this Purchase Warrant) to receive upon the exercise hereof, for the same aggregate
Exercise Price payable hereunder immediately prior to such event, the kind and amount of shares of stock or other securities or
property (including cash) receivable upon such reclassification, reorganization, share reconstruction or amalgamation, or consolidation,
or upon a dissolution following any such sale or transfer, by a holder of the number of Shares of the Company issuable upon exercise
of this Purchase Warrant immediately prior to such event; and if any reclassification also results in a change in Shares covered
by Section 6.1.1 or 6.1.2, then such adjustment shall be made pursuant to Sections 6.1.1, 6.1.2 and this Section 6.1.3. The provisions
of this Section 6.1.3 shall similarly apply to successive reclassifications, reorganizations, share reconstructions or amalgamations,
or consolidations, sales or other transfers.


 


6.1.4
 Changes in Form of Purchase Warrant. This form of Purchase Warrant need not be changed
because of any change pursuant to this Section 6.1, and Purchase Warrants issued after such change may state the same Exercise
Price and the same number of Shares as are stated in the Purchase Warrants initially issued pursuant to this Agreement. The acceptance
by any Holder of the issuance of new Purchase Warrants reflecting a required or permissive change shall not be deemed to waive
any rights to an adjustment occurring after the Commencement Date or the computation thereof.


 




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6.2
 Substitute Purchase Warrant. In case of any consolidation of the
Company with, or share reconstruction or amalgamation of the Company with or into, another corporation (other than a consolidation
or share reconstruction or amalgamation which does not result in any reclassification or change of the outstanding Shares), the
corporation formed by such consolidation or share reconstruction or amalgamation shall execute and deliver to the Holder a supplemental
Purchase Warrant providing that the holder of each Purchase Warrant then outstanding or to be outstanding shall have the right
thereafter (until the stated expiration of such Purchase Warrant) to receive, upon exercise of such Purchase Warrant, the kind
and amount of shares of stock and other securities and property receivable upon such consolidation or share reconstruction or
amalgamation, by a holder of the number of Shares for which such Purchase Warrant might have been exercised immediately prior
to such consolidation, share reconstruction or amalgamation, sale or transfer. Such supplemental Purchase Warrant shall provide
for adjustments which shall be identical to the adjustments provided for in this Section 6. The above provision of this Section
shall similarly apply to successive consolidations or share reconstructions or amalgamations.


 


6.3  
 Elimination of Fractional Interests. The Company shall not be required to issue certificates
representing fractions of Shares upon the exercise of the Purchase Warrant, nor shall it be required to issue scrip or pay cash
in lieu of any fractional interests, it being the intent of the parties that all fractional interests shall be eliminated by rounding
any fraction up or down, as the case may be, to the nearest whole number of Shares or other securities, properties or rights.


 


7.
 Reservation and Listing. The Company shall at all times reserve
and keep available out of its authorized Shares, solely for the purpose of issuance upon exercise of the Purchase Warrants, such
number of Shares or other securities, properties or rights as shall be issuable upon the exercise thereof. The Company covenants
and agrees that, upon exercise of the Purchase Warrants and payment of the Exercise Price therefor, in accordance with the terms
hereby, all Shares and other securities issuable upon such exercise shall be duly and validly issued, fully paid and non-assessable
and not subject to preemptive rights of any stockholder. As long as the Purchase Warrants shall be outstanding, the Company shall
use its commercially reasonable efforts to cause all Shares issuable upon exercise of the Purchase Warrants to be listed (subject
to official notice of issuance) on all national securities exchanges (or, if applicable, on the OTC Bulletin Board or any successor
trading market) on which the Shares issued to the public in the Offering may then be listed and/or quoted.


 


8.  Certain
Notice Requirements.


 


8.1 No
Rights as Stockholder. No Holder shall be entitled to vote or receive dividends or distributions or
be deemed the holder of any equity securities which may at any time be issuable on the exercise hereof, nor shall anything
contained herein be construed to confer upon the Holder, as such, any of the rights of a stockholder of the Company or any
right to vote for the election of directors or upon any matter submitted to stockholders at any meeting thereof, or to give
or withhold consent to any corporate action (whether upon any recapitalization, issuance of stock, reclassification of stock,
change of par value, consolidation, merger, conveyance, or otherwise) or to receive notice of meetings, or to receive dividends
or distributions, or to share in the assets of the Company in the event of a liquidation, dissolution or the winding up of the
Company, until the Purchase Warrant shall have been exercised and the Shares shall have become deliverable, as provided herein.



 


8.2  Certain
Notices. If at any time prior to the expiration of the Purchase Warrants and their exercise, any of the events described in
Section 8.3 shall occur, then, in one or more of said events, the Company shall give written notice of such event at least fifteen
(15) days prior to the date fixed as a record date or the date of closing the transfer books for the determination of the stockholders
entitled to such dividend, distribution, conversion or exchange of securities or subscription rights, or entitled to vote on such
proposed dissolution, liquidation, winding up or sale. Such notice shall specify such record date or the date of the closing of
the transfer books, as the case may be. Notwithstanding the foregoing, the Company shall deliver to each Holder a copy of each
notice given to the other stockholders of the Company at the same time and in the same manner that such notice is given to the
stockholders.


  




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8.3
 Events Requiring Notice. The Company shall be required to give the
notice described in this Section 8 upon one or more of the following events: (i) if the Company shall take a record of the holders
of its Shares for the purpose of entitling them to receive a dividend or distribution payable otherwise than in cash, or a cash
dividend or distribution payable otherwise than out of retained earnings, as indicated by the accounting treatment of such dividend
or distribution on the books of the Company; (ii) the Company shall offer to all the holders of its Shares any additional shares
of capital stock of the Company or securities convertible into or exchangeable for shares of capital stock of the Company, or
any option, right or warrant to subscribe therefor; or (iii) a dissolution, liquidation or winding up of the Company (other than
in connection with a consolidation or share reconstruction or amalgamation) or a sale of all or substantially all of its property,
assets and business shall be proposed.


 


8.4
 Notice of Change in Exercise Price. The Company shall, promptly after
an event requiring a change in the Exercise Price pursuant to Section 6 hereof, send notice to the Holders of such event and change
(“Price Notice”). The Price Notice shall describe the event causing the change and the method of calculating
same and shall be certified as being true and accurate by the Company’s Chief Financial Officer.


 


8.5
   Transmittal of Notices. All notices, requests, consents and other communications
under this Purchase Warrant shall be in writing and shall be deemed to have been duly made when hand delivered or mailed by express
mail or private courier service: (i) if to the registered Holder of the Purchase Warrant, to the address of such Holder as shown
on the books of the Company, or (ii) if to the Company, to following address or to such other address as the Company may designate
by notice to the Holders:


 


If
to the Holder:


 


Kingswood
Capital Markets

17 Battery Place, Suite 625

New York, New York 10004

Attn: Joseph T. Rallo


 


with
a copy (which shall not constitute notice) to:


 




Nelson Mullins Riley & Scarborough LLP


101
Constitution Avenue NW, Suite 900


Washington,
DC 20001


Attn:
Andrew M. Tucker, Esq.


Fax
No.: (202) 689-2860


 


If
to the Company:


 


Longeveron
Inc.


1951
NW 7th Avenue, Suite 520


Miami,
Florida 33136


Attn:
Geoff Green


Fax
No.: 844-879-5154


 


with
a copy (which shall not constitute notice) to:


 


Buchanan
Ingersoll & Rooney PC


Union
Trust Building


501
Grant Street, Suite 200


Pittsburgh,
Pennsylvania 15219


Attn:
Jennifer Minter, Esq.


Fax
No.: (412) 562-1041


 




    8


     


    

 


9.  Miscellaneous.


 


9.1 Amendments.
The Company and Kingswood may from time to time supplement or amend this Purchase Warrant without the approval of any of the Holders
in order to cure any ambiguity, to correct or supplement any provision contained herein that may be defective or inconsistent
with any other provisions herein, or to make any other provisions in regard to matters or questions arising hereunder that the
Company and Kingswood may deem necessary or desirable and that the Company and Kingswood deem shall not adversely affect the interest
of the Holders. All other modifications or amendments shall require the written consent of and be signed by the party against
whom enforcement of the modification or amendment is sought.


 


9.2
 Headings. The headings contained herein are for the sole purpose
of convenience of reference, and shall not in any way limit or affect the meaning or interpretation of any of the terms or provisions
of this Purchase Warrant.


 


9.3.
  Entire Agreement. This Purchase Warrant (together with the other agreements and
documents being delivered pursuant to or in connection with this Purchase Warrant) constitutes the entire agreement of the parties
hereto with respect to the subject matter hereof, and supersedes all prior agreements and understandings of the parties, oral
and written, with respect to the subject matter hereof.


 


9.4
   Binding Effect. This Purchase Warrant shall inure solely to the benefit
of and shall be binding upon, the Holder and the Company and their permitted assignees, respective successors, legal representative
and assigns, and no other person shall have or be construed to have any legal or equitable right, remedy or claim under or in
respect of or by virtue of this Purchase Warrant or any provisions herein contained.


 


9.5
 Governing Law; Submission to Jurisdiction; Trial by Jury. This Purchase
Warrant shall be governed by and construed and enforced in accordance with the laws of the State of New York, without giving effect
to conflict of laws principles thereof. The Company hereby agrees that any action, proceeding or claim against it arising out
of, or relating in any way to this Purchase Warrant shall be brought and enforced in the New York Supreme Court, County of New
York, or in the United States District Court for the Southern District of New York, and irrevocably submits to such jurisdiction,
which jurisdiction shall be exclusive. The Company hereby waives any objection to such exclusive jurisdiction and that such courts
represent an inconvenient forum. Any process or summons to be served upon the Company may be served by transmitting a copy thereof
by registered or certified mail, return receipt requested, postage prepaid, addressed to it at the address set forth in Section
8 hereof. Such mailing shall be deemed personal service and shall be legal and binding upon the Company in any action, proceeding
or claim. The Company and the Holder agree that the prevailing party(ies) in any such action shall be entitled to recover from
the other party(ies) all of its reasonable attorneys’ fees and expenses relating to such action or proceeding and/or incurred
in connection with the preparation therefor. The Company (on its behalf and, to the extent permitted by applicable law, on behalf
of its stockholders and affiliates) and the Holder hereby irrevocably waive, to the fullest extent permitted by applicable law,
any and all right to trial by jury in any legal proceeding arising out of or relating to this Agreement or the transactions contemplated
hereby.


  


9.6
 Waiver, etc. The failure of the Company or the Holder to at any time
enforce any of the provisions of this Purchase Warrant shall not be deemed or construed to be a waiver of any such provision,
nor to in any way affect the validity of this Purchase Warrant or any provision hereof or the right of the Company or any Holder
to thereafter enforce each and every provision of this Purchase Warrant. No waiver of any breach, non-compliance or non-fulfillment
of any of the provisions of this Purchase Warrant shall be effective unless set forth in a written instrument executed by the
party or parties against whom or which enforcement of such waiver is sought; and no waiver of any such breach, non-compliance
or non-fulfillment shall be construed or deemed to be a waiver of any other or subsequent breach, non-compliance or non-fulfillment.


 


9.7   
 Execution in Counterparts. This Purchase Warrant may be executed in one or more counterparts,
and by the different parties hereto in separate counterparts, each of which shall be deemed to be an original, but all of which
taken together shall constitute one and the same agreement, and shall become effective when one or more counterparts has been
signed by each of the parties hereto and delivered to each of the other parties hereto. Such counterparts may be delivered by
facsimile transmission or other electronic transmission.


9.8
   Exchange Agreement. As a condition of the Holder’s receipt and acceptance
of this Purchase Warrant, Holder agrees that, at any time prior to the complete exercise of this Purchase Warrant by Holder, if
the Company and Kingswood enter into an agreement (“Exchange Agreement”) pursuant to which they agree that
all outstanding Purchase Warrants will be exchanged for securities or cash or a combination of both, then Holder shall agree to
such exchange and become a party to the Exchange Agreement.


 


[Signature
Page Follows]


 




    9


     


    

 


IN
WITNESS WHEREOF, the Company has caused this Purchase Warrant to be signed by its duly authorized officer as of the 16th day of
February, 2021.


 


	LONGEVERON
    INC.	 
	 	 	 
	By:	/s/
    Geoff Green	 
	 	Name:
    Geoff Green	 
	 	Title:
    Chief Executive Officer	 


 




     


     


    

 


[Form
to be used to exercise Purchase Warrant]


 


Date:
__________, 20___


 


The
undersigned hereby elects irrevocably to exercise the Purchase Warrant for ______ shares of common stock, par value $0.001 per
share (the “Shares”), of Longeveron Inc., a Delaware corporation (the “Company”), and hereby
makes payment of $____ (at the rate of $____ per Share) in payment of the Exercise Price pursuant thereto. Please issue the Shares
as to which this Purchase Warrant is exercised in accordance with the instructions given below and, if applicable, a new Purchase
Warrant representing the number of Shares for which this Purchase Warrant has not been exercised.


 


or


 


The
undersigned is entitled to pursuant to Section 2.2 of the Purchase Warrant, and hereby elects irrevocably, to convert its right
to purchase ___ Shares of the Company under the Purchase Warrant for ______ Shares, as determined in accordance with the following
formula:


 


	 	X	=	Y(A-B)	 
	A	 
	Where,	 	 	 
	 	X	=	The
    number of Shares to be issued to Holder;
	 	Y	=	The
    number of Shares for which the Purchase Warrant is being exercised;
	 	A	=	The
    fair market value of one Share which is equal to $_____; and
	 	B	=	The
    Exercise Price which is equal to $______ per share
	 	 	 	 	 	 	 


The
undersigned agrees and acknowledges that the calculation and its ability set forth above is subject to confirmation by the Company
and any disagreement with respect to the calculation shall be resolved by the Company in its sole discretion.


 


Please
issue the Shares as to which this Purchase Warrant is exercised in accordance with the instructions given below and, if applicable,
a new Purchase Warrant representing the number of Shares for which this Purchase Warrant has not been converted.


 


	Signature
    	 	 


 


	Signature
    Guaranteed 	 	 


 


INSTRUCTIONS
FOR REGISTRATION OF SECURITIES


 


	Name:
    	 	 
	 	(Print
    in Block Letters)	 


 


	Address:
    	 	 
	 	 	 
	 	 	 
	 	 	 
	 	 	 


 


NOTICE:
The signature to this form must correspond with the name as written upon the face of the Purchase Warrant without alteration or
enlargement or any change whatsoever, and must be guaranteed by a bank, other than a savings bank, or by a trust company or by
a firm having membership on a registered national securities exchange.


 




     


     


    

 


[Form
to be used to assign Purchase Warrant]


 


ASSIGNMENT


 


(To
be executed by the registered Holder to effect a transfer of the within Purchase Warrant):


 


FOR
VALUE RECEIVED, __________________ does hereby sell, assign and transfer unto ___________________the right to purchase shares
of Class A common stock, par value $0.001 per share, of Longeveron Inc., a Delaware corporation (the “Company”),
evidenced by the Purchase Warrant and does hereby authorize the Company to transfer such right on the books of the Company.


 


Dated:
__________, 20__


 


	Signature
    	 	 


 


	Signature
    Guaranteed 	 	 


 


NOTICE:
The signature to this form must correspond with the name as written upon the face of the within Purchase Warrant without alteration
or enlargement or any change whatsoever, and must be guaranteed by a bank, other than a savings bank, or by a trust company or
by a firm having membership on a registered national securities exchange. 


  




     


     


    

 


EXHIBIT
B


 


Form
of Lock-Up Agreement


 


Lock-Up
Agreement


 


February
11, 2021


 


Kingswood
Capital Markets,


division
of Benchmark Investments, Inc.


as
Representative of the Underwriters

17 Battery Place, Suite 625


New
York, New York 10004 


 


Ladies
and Gentlemen:


 


The
undersigned understands that Kingswood Capital Markets, division of Benchmark Investments, Inc. (the “Representative”)
proposes to enter into an Underwriting Agreement (the “Underwriting Agreement”) with Longeveron Inc., a Delaware
corporation (the “Company”), providing for the public offering (the “Public Offering”) of
shares of Class A Common Stock, par value $0.001 per share, of the Company (the “Shares”).


 


To
induce the Representative to continue its efforts in connection with the Public Offering, the undersigned hereby agrees that,
without the prior written consent of the Representative, the undersigned will not, during the period commencing on the date hereof
and ending 180 days after the date of the final prospectus (the “Prospectus”) relating to the Public Offering
(the “Lock-Up Period”), (1) offer, pledge, sell, contract to sell, grant, lend, or otherwise transfer or dispose
of, directly or indirectly, any Shares or any securities convertible into or exercisable or exchangeable for Shares, whether now
owned or hereafter acquired by the undersigned or with respect to which the undersigned has or hereafter acquires the power of
disposition (collectively, the “Lock-Up Securities”); (2) enter into any swap or other arrangement that transfers
to another, in whole or in part, any of the economic consequences of ownership of the Lock-Up Securities, whether any such transaction
described in clause (1) or (2) above is to be settled by delivery of Lock-Up Securities, in cash or otherwise; (3) make any demand
for or exercise any right with respect to the registration of any Lock-Up Securities; or (4) publicly disclose the intention to
make any offer, sale, pledge or disposition, or to enter into any transaction, swap, hedge or other arrangement relating to any
Lock-Up Securities. Notwithstanding the foregoing, and subject to the conditions below, the undersigned may transfer Lock-Up Securities
without the prior written consent of the Representative in connection with (a) transactions relating to Lock-Up Securities acquired
in open market transactions after the completion of the Public Offering; provided that no filing under Section 13
or Section 16(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or other public
announcement shall be required or shall be voluntarily made during the Lock-Up Period in connection with subsequent sales of Lock-Up
Securities acquired in such open market transactions; (b) transfers of Lock-Up Securities as a bona fide gift, by will
or intestacy or to a family member or trust for the benefit of a family member (for purposes of this lock-up agreement, “family
member” means any relationship by blood, marriage or adoption, not more remote than first cousin); (c) transfers of Lock-Up
Securities to a charity or educational institution; or (d) if the undersigned, directly or indirectly, is or controls a corporation,
partnership, limited liability company or other business entity, any transfers of Lock-Up Securities to any shareholder, partner
or member of, or owner of similar equity interests in, the undersigned, as the case may be; provided that in the case of
any transfer pursuant to the foregoing clauses (b), (c) or (d), (i) it shall be a condition to any such transfer that (i) the
transferee/donee agrees to be bound by the terms of this lock-up agreement (including, without limitation, the restrictions set
forth in the preceding sentence) to the same extent as if the transferee/donee were a party hereto; (ii) each party (donor, donee,
transferor or transferee) shall not be required by law (including without limitation the disclosure requirements of the Securities
Act of 1933, as amended (the “Securities Act”), and the Exchange Act) to make, and shall agree to not voluntarily
make, any filing or public announcement of the transfer or disposition prior to the expiration of the Lock-Up Period; and (iii)
the undersigned notifies the Representative at least two (2) business days prior to the proposed transfer or disposition.


 




     


     


    

 


In
addition, the foregoing restrictions shall not apply to (i) the exercise of stock options granted pursuant to the Company’s
equity incentive plans or to any of the undersigned’s Class A Common Stock issued upon such exercise, (ii) exercise of warrants;
provided that it shall apply to any of the undersigned’s Class A Common Stock issued upon such exercise, or (iii) pursuant
to an existing contract, instruction or plan (a “Plan”) that satisfies all of the requirements of Rule 10b5-1(c)(1)(i)(B)
under the Exchange Act, (iv) the establishment of any new Plan; provided that no sales of the undersigned’s Class A Common
Stock shall be made pursuant to such new Plan prior to the expiration of the Lock-Up Period (as such may have been extended pursuant
to the provisions hereof), and such a Plan may only be established if no public announcement of the establishment or existence
thereof and no filing with the Securities and Exchange Commission or other regulatory authority in respect thereof or transactions
thereunder or contemplated thereby, by the undersigned, the Company or any other person, shall be required, and no such announcement
or filing is made voluntarily, by the undersigned, the Company or any other person, prior to the expiration of the Lock-Up Period
(as such may have been extended pursuant to the provisions hereof).


 


The
undersigned also agrees and consents to the entry of stop transfer instructions with the Company’s transfer agent and registrar
against the transfer of the undersigned’s securities subject to this this lock-up agreement except in compliance with this
this lock-up agreement.


 


If
the undersigned is an officer or director of the Company, (i) the undersigned agrees that the foregoing restrictions shall be
equally applicable to any Shares that the undersigned may purchase in the Public Offering; (ii) the Representative agrees that,
at least three (3) business days before the effective date of any release or waiver of the foregoing restrictions in connection
with a transfer of Lock-Up Securities, the Representative will notify the Company of the impending release or waiver; and (iii)
the Company has agreed in the Underwriting Agreement to announce the impending release or waiver by press release through a major
news service at least two (2) business days before the effective date of the release or waiver. Any release or waiver granted
by the Representative hereunder to any such officer or director shall only be effective two (2) business days after the publication
date of such press release. The provisions of this paragraph will not apply if (a) the release or waiver is effected solely to
permit a transfer of Lock-Up Securities not for consideration and (b) the transferee has agreed in writing to be bound by the
same terms described in this lock-up agreement to the extent and for the duration that such terms remain in effect at the time
of such transfer.


 


The
undersigned understands that the Company and the Representative are relying upon this lock-up agreement in proceeding toward consummation
of the Public Offering. The undersigned further understands that this lock-up agreement is irrevocable and shall be binding upon
the undersigned’s heirs, legal representatives, successors and assigns.


 


The
undersigned understands that, if the Underwriting Agreement does not become effective, or if the Underwriting Agreement (other
than the provisions thereof which survive termination) shall terminate or be terminated prior to payment for and delivery of the
Shares to be sold thereunder, the undersigned shall be released from all obligations under this lock-up agreement.


  


This
lock-up agreement shall be governed by, and construed in accordance with, the laws of the State of New York.


 


	 	Very
    truly yours,
	 	 
	 	 
	 	(Name
    - Please Print)
	 	 
	 	 
	 	(Signature)
	 	 
	 	 
	 	(Name
    of Signatory, in the case of entities - Please Print)
	 	 
	 	 
	 	(Title
    of Signatory, in the case of entities - Please Print)
	 	 	 
	 	Address: