EXHIBIT 4.1


 


NEITHER THIS SECURITY NOR THE SECURITIES FOR WHICH
THIS SECURITY IS EXERCISABLE HAVE 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. THIS SECURITY AND THE SECURITIES ISSUABLE UPON EXERCISE OF THIS SECURITY MAY BE PLEDGED IN CONNECTION
WITH A BONA FIDE MARGIN ACCOUNT OR OTHER LOAN SECURED BY SUCH SECURITIES.


 


COMMON STOCK PURCHASE WARRANT


 


BIOSTAGE,
INC.


 


	Warrant Shares: [_____________]	Issue Date:	May [___], 2022


 


THIS COMMON STOCK PURCHASE WARRANT
(the “Warrant”) certifies that, for value received, [_____________] or such holder’s assigns (the “Holder”)
is entitled, upon the terms and subject to the limitations on exercise and the conditions hereinafter set forth, at any time on or after
the date hereof and on or prior to the close of business on the Termination Date but not thereafter, to subscribe for and purchase from
Biostage, Inc., a Delaware corporation (the “Company”), up to [_____________] shares (as subject to limitations and
adjustment hereunder, the “Warrant Shares”) of Common Stock. The purchase price of one share of Common Stock under
this Warrant shall be equal to the Exercise Price, as defined in Section 2(b).


 


Section 1.            Definitions.


 


Capitalized terms used and
not otherwise defined herein shall have the meanings set forth in that certain Securities Purchase Agreement (the “Purchase Agreement”),
dated as of the date hereof, among the Company and the Holder. In addition to the terms defined elsewhere in this Warrant or in the Purchase
Agreement, the following terms have the meanings set forth in this Section 1:


 


“Common Stock”
means the common stock of the Company, par value $0.01 per share, and any other class of securities into which such securities may hereafter
be reclassified or changed.


 


“Common Stock Equivalents”
means any securities of the Company or its subsidiaries which would entitle the holder thereof to acquire at any time Common Stock, including,
without limitation, any debt, preferred stock, right, option, warrant or other instrument that is at any time convertible into or exercisable
or exchangeable for, or otherwise entitles the holder thereof to receive, Common Stock.


 


“Termination Date”
means the five (5) year anniversary of the date of issuance of this Warrant.


 


“Trading Day”
means a day on which the principal Trading Market is open for trading.


 


“Trading Market”
means any of the following markets or exchanges on which the Common Stock is listed or quoted for trading on the date in question: the
NYSE MKT, the Nasdaq Capital Market, the Nasdaq Global Market, the Nasdaq Global Select Market, the New York Stock Exchange, OTCQB or
OTCQX (or any successors to any of the foregoing).


 


“VWAP”
means, for any date, the price determined by the first of the following clauses that applies: (a) if the Common Stock is then listed
or quoted on a Trading Market, the daily volume weighted average price of the Common Stock for such date (or the nearest preceding
date) on the Trading Market on which the Common Stock is then listed or quoted as reported by Bloomberg L.P. (based on a Trading Day
from 9:30 a.m. (New York City time) to 4:02 p.m. (New York City time)), (b)  if OTCQB or OTCQX is not a Trading Market, the
volume weighted average price of the Common Stock for such date (or the nearest preceding date) on OTCQB or OTCQX as applicable, (c)
if the Common Stock is not then listed or quoted for trading on OTCQB or OTCQX and if prices for the Common Stock are then reported
in the “Pink Sheets” published by OTC Markets, Inc. (or a similar organization or agency succeeding to its functions of
reporting prices), the most recent bid price per share of the Common Stock so reported, or (d) in all other cases, the fair
market value of a share of Common Stock as determined by an independent appraiser selected in good faith by the Holders of a
majority in interest of the Securities then outstanding and reasonably acceptable to the Company, the fees and expenses of which
shall be paid by the Company.


 






     


     


    

 


Section 2.            Exercise.


 


a)          Exercise
of Warrant. Exercise of the purchase rights represented by this Warrant may be made, in whole or in part, at any time or times on
or after date hereof and on or before the Termination Date by delivery to the Company (or such other office or agency of the Company as
it may designate by notice in writing to the registered Holder at the address of the Holder appearing on the books of the Company) of
a duly executed facsimile copy (or e-mail attachment) of the Notice of Exercise in the form annexed hereto. Within three (3) Trading Days
following the date of exercise as aforesaid, the Holder shall deliver the aggregate Exercise Price for the shares specified in the applicable
Notice of Exercise by wire transfer or cashier’s check drawn on a United States bank. No ink-original Notice of Exercise shall be
required, nor shall any medallion guarantee (or other type of guarantee or notarization) of any Notice of Exercise form be required. Notwithstanding
anything herein to the contrary, the Holder shall not be required to physically surrender this Warrant to the Company until the Holder
has purchased all of the Warrant Shares available hereunder and the Warrant has been exercised in full, in which case, the Holder shall
surrender this Warrant to the Company for cancellation within three (3) Trading Days of the date the final Notice of Exercise is delivered
to the Company. Partial exercises of this Warrant resulting in purchases of a portion of the total number of Warrant Shares available
hereunder shall have the effect of lowering the outstanding number of Warrant Shares purchasable hereunder in an amount equal to the applicable
number of Warrant Shares purchased. The Holder and the Company shall maintain records showing the number of Warrant Shares purchased and
the date of such purchases. The Company shall deliver any objection to any Notice of Exercise within one (1) Business Day of receipt of
such notice. The Holder and any assignee, by acceptance of this Warrant, acknowledge and agree that, by reason of the provisions of
this paragraph, following the purchase of a portion of the Warrant Shares hereunder, the number of Warrant Shares available for purchase
hereunder at any given time may be less than the amount stated on the face hereof.


 


b)          Exercise
Price. The exercise price per share of the Common Stock under this Warrant shall be $8.88, subject to adjustment hereunder (the “Exercise
Price”).


 


c)          Mechanics
of Exercise.


 


i.            Delivery
of Warrant Shares Upon Exercise. Warrant Shares purchased hereunder shall be transmitted by the Transfer Agent to the Holder by
crediting the account of the Holder’s or its designee’s balance account with The Depository Trust Company through its
Deposit or Withdrawal at Custodian system (“DWAC”) if the Company is then a participant in such system and either
(A) there is an effective registration statement permitting the issuance of the Warrant Shares to or resale of the Warrant Shares by
the Holder (although for avoidance of any doubt, the Company is not obligated in any manner or circumstance to file or maintain any
such resale registration statement) or (B) the Warrant Shares are eligible for resale by the Holder without volume or manner-of-sale
limitations pursuant to Rule 144, and otherwise by physical delivery of a certificate or evidence of book entry, in each case
registered in the Company’s share register in the name of the Holder or its designee, for the number of Warrant Shares to
which the Holder is entitled pursuant to such exercise to the address specified by the Holder in the Notice of Exercise by the date
that is three (3) Trading Days after the delivery to the Company of the Notice of Exercise (such date, the “Warrant Share
Delivery Date”). Upon delivery of the Notice of Exercise the Holder shall be deemed for all corporate purposes to have
become the holder of record of the Warrant Shares with respect to which this Warrant has been exercised, irrespective of the date of
delivery of the Warrant Shares; provided payment of the aggregate Exercise Price is received within three Trading Days of delivery
of the Notice of Exercise. If the Company fails for any reason to deliver to the Holder the Warrant Shares subject to a Notice of
Exercise by the Warrant Share Delivery Date, the Company shall pay to the Holder, in cash, as liquidated damages and not as a
penalty, for each $1,000 of Warrant Shares subject to such exercise (based on the VWAP of the Common Stock on the date of the
applicable Notice of Exercise), $5 per Trading Day (increasing to $10 per Trading Day on the fifth Trading Day after such liquidated
damages begin to accrue) for each Trading Day after such Warrant Share Delivery Date until such Warrant Shares are delivered or
Holder rescinds such exercise. The Company agrees to maintain a transfer agent that is a participant in the FAST program so long as
this Warrant remains outstanding and exercisable.


 






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ii.            Delivery
of New Warrants Upon Exercise. If this Warrant shall have been exercised in part, the Company shall, at the request of a Holder and
upon surrender of this Warrant certificate, at the time of delivery of the Warrant Shares, deliver to the Holder a new Warrant evidencing
the rights of the Holder to purchase the unpurchased Warrant Shares called for by this Warrant, which new Warrant shall in all other respects
be identical with this Warrant.


 


iii.         Rescission
Rights. If the Company fails to cause the Transfer Agent to transmit to the Holder the Warrant Shares pursuant to Section 2(c)(i)
by the Warrant Share Delivery Date, then the Holder will have the right to rescind such exercise.


 


iv.         Compensation
for Buy-In on Failure to Timely Deliver Warrant Shares Upon Exercise. In addition to any other rights available to the Holder, if
the Company fails to cause the Transfer Agent to transmit to the Holder the Warrant Shares in accordance with the provisions of Section
2(c)(i) above pursuant to an exercise on or before the Warrant Share Delivery Date, and if after such date the Holder is required by its
broker to purchase (in an open market transaction or otherwise) or the Holder’s brokerage firm otherwise purchases, shares of Common
Stock to deliver in satisfaction of a sale by the Holder of the Warrant Shares which the Holder anticipated receiving upon such exercise
(a “Buy-In”), then the Company shall (A) pay in cash to the Holder the amount, if any, by which (x) the Holder’s
total purchase price (including brokerage commissions, if any) for the shares of Common Stock so purchased exceeds (y) the amount obtained
by multiplying (1) the number of Warrant Shares that the Company was required to deliver to the Holder in connection with the exercise
at issue times (2) the price at which the sell order giving rise to such purchase obligation was executed, and (B) at the option of the
Holder, either reinstate the portion of the Warrant and equivalent number of Warrant Shares for which such exercise was not honored (in
which case such exercise shall be deemed rescinded) or deliver to the Holder the number of shares of Common Stock that would have been
issued had the Company timely complied with its exercise and delivery obligations hereunder. For example, if the Holder purchases Common
Stock having a total purchase price of $11,000 to cover a Buy-In with respect to an attempted exercise of shares of Common Stock with
an aggregate sale price giving rise to such purchase obligation of $10,000, under clause (A) of the immediately preceding sentence the
Company shall be required to pay the Holder $1,000. The Holder shall provide the Company written notice indicating the amounts payable
to the Holder in respect of the Buy-In and, upon request of the Company, evidence of the amount of such loss. Nothing herein shall limit
a Holder’s right to pursue any other remedies available to it hereunder, at law or in equity including, without limitation, a decree
of specific performance and/or injunctive relief with respect to the Company’s failure to timely deliver shares of Common Stock
upon exercise of the Warrant as required pursuant to the terms hereof.


 






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v.           No
Fractional Shares or Scrip. No fractional shares or scrip representing fractional shares shall be issued upon the exercise of this
Warrant. As to any fraction of a share which the Holder would otherwise be entitled to purchase upon such exercise, the Company shall,
at its election, either pay a cash adjustment in respect of such final fraction in an amount equal to such fraction multiplied by the
VWAP as of the date of the applicable Notice of Exercise or round up to the next whole share.


 


vi.         Charges,
Taxes and Expenses. Issuance of Warrant Shares shall be made without charge to the Holder for any issue or transfer tax or other incidental
expense in respect of the issuance of Warrant Shares, all of which taxes and expenses shall be paid by the Company, and such Warrant Shares
shall be issued in the name of the Holder or in such name or names as may be directed by the Holder; provided, however,
that in the event that Warrant Shares are to be issued in a name other than the name of the Holder, this Warrant when surrendered for
exercise shall be accompanied by the Assignment Form attached hereto duly executed by the Holder and the Company may require, as a condition
thereto, the payment of a sum sufficient to reimburse it for any transfer tax incidental thereto. The Company shall pay all Transfer Agent
fees required for same-day processing of any Notice of Exercise and all fees to the Depository Trust Company (or another established clearing
corporation performing similar functions) required for same-day electronic delivery of the Warrant Shares.


 


vii.         Closing
of Books. The Company will not close its stockholder books or records in any manner which prevents the timely exercise of this Warrant,
pursuant to the terms hereof.


 


d)          Holder’s
Exercise Limitations. The Company shall not effect any exercise of this Warrant, and a Holder shall not have the right to
exercise any portion of this Warrant, pursuant to Section 2 or otherwise, to the extent that after giving effect to such issuance
after exercise as set forth on the applicable Notice of Exercise, the Holder (together with the Holder’s Affiliates, and any
other Persons acting as a group together with the Holder or any of the Holder’s Affiliates (such Persons,
 “Attribution Parties”)), would beneficially own in excess of the Beneficial Ownership Limitation (as defined
below).  For purposes of the foregoing sentence, the number of shares of Common Stock beneficially owned by the Holder and its
Affiliates and Attribution Parties shall include the number of shares of Common Stock issuable upon exercise of this Warrant with
respect to which such determination is being made, but shall exclude the number of shares of Common Stock which would be issuable
upon (i) exercise of the remaining, nonexercised portion of this Warrant beneficially owned by the Holder or any of its Affiliates
or Attribution Parties and (ii) exercise or conversion of the unexercised or nonconverted portion of any other securities of the
Company (including, without limitation, any other Common Stock Equivalents) subject to a limitation on conversion or exercise
analogous to the limitation contained herein beneficially owned by the Holder or any of its Affiliates or Attribution Parties. 
Except as set forth in the preceding sentence, for purposes of this Section 2(d), beneficial ownership shall be calculated in
accordance with Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder, it being acknowledged by the
Holder that the Company is not representing to the Holder that such calculation is in compliance with Section 13(d) of the Exchange
Act and the Holder is solely responsible for any schedules required to be filed in accordance therewith. To the extent that the
limitation contained in this Section 2(d) applies, the determination of whether this Warrant is exercisable (in relation to other
securities owned by the Holder together with any Affiliates and Attribution Parties) and of which portion of this Warrant is
exercisable shall be in the reasonable discretion of the Holder, and the submission of a Notice of Exercise shall be deemed to be
the Holder’s determination of whether this Warrant is exercisable (in relation to other securities owned by the Holder
together with any Affiliates and Attribution Parties) and of which portion of this Warrant is exercisable, in each case subject to
the Beneficial Ownership Limitation, and the Company shall provide the Holder necessary assistance to verify or confirm the accuracy
of such determination. In addition, a determination as to any group status as contemplated above shall be determined in accordance
with Section 13(d) of the Exchange Act and the rules and regulations promulgated thereunder. For purposes of this Section 2(d), in
determining the number of outstanding shares of Common Stock, a Holder may rely on the number of outstanding shares of Common Stock
as reflected in (A) the Company’s most recent periodic or annual report filed with the Commission, as the case may be, (B) a
more recent public announcement by the Company or (C) a more recent written notice by the Company or the Transfer Agent setting
forth the number of shares of Common Stock outstanding.  Upon the written or oral request of a Holder, the Company shall within
two Trading Days confirm orally and in writing to the Holder the number of shares of Common Stock then outstanding.  In any
case, the number of outstanding shares of Common Stock shall be determined after giving effect to the conversion or exercise of
securities of the Company, including this Warrant, by the Holder or its Affiliates or Attribution Parties since the date as of which
such number of outstanding shares of Common Stock was reported. The “Beneficial Ownership Limitation” shall be
4.99% of the number of shares of the Common Stock outstanding immediately after giving effect to the issuance of shares of Common
Stock issuable upon exercise of this Warrant. The provisions of this paragraph shall be construed and implemented in a manner
otherwise than in strict conformity with the terms of this Section 2(d) to correct this paragraph (or any portion hereof) which may
be defective or inconsistent with the intended Beneficial Ownership Limitation herein contained or to make changes or supplements
necessary or desirable to properly give effect to such limitation. The limitations contained in this paragraph shall apply to a
successor holder of this Warrant. 


 






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Section 3.            Certain
Adjustments.


 


a)          Stock
Dividends and Splits. If the Company, at any time while this Warrant is outstanding: (i) pays a stock dividend or otherwise makes
a distribution or distributions on shares of its Common Stock or any other equity or equity equivalent securities payable in shares of
Common Stock (which, for avoidance of doubt, shall not include any shares of Common Stock issued by the Company upon exercise of this
Warrant), (ii) subdivides outstanding shares of Common Stock into a larger number of shares, (iii) combines (including by way of reverse
stock split) outstanding shares of Common Stock into a smaller number of shares or (iv) issues by reclassification of shares of the Common
Stock any shares of capital stock of the Company, then in each case the Exercise Price shall be multiplied by a fraction of which the
numerator shall be the number of shares of Common Stock (excluding treasury shares, if any) outstanding immediately before such event
and of which the denominator shall be the number of shares of Common Stock outstanding immediately after such event, and the number of
shares issuable upon exercise of this Warrant shall be proportionately adjusted such that the aggregate Exercise Price of this Warrant
shall remain unchanged, subject to the limitation on fractional shares in Section 2(c)(v). Any adjustment made pursuant to this Section
3(a) shall become effective immediately after the record date for the determination of stockholders entitled to receive such dividend
or distribution and shall become effective immediately after the effective date in the case of a subdivision, combination or re-classification.


 


b)          Pro
Rata Distributions. During such time as this Warrant is outstanding, if the Company shall declare or make any dividend or other distribution
of its assets (or rights to acquire its assets) to holders of shares of Common Stock, by way of return of capital or otherwise (including,
without limitation, any distribution of cash, stock or other securities, property or options by way of a dividend, spin off, reclassification,
corporate rearrangement, scheme of arrangement or other similar transaction) (a "Distribution"), at any time after the
issuance of this Warrant, then, in each such case, the Holder shall be entitled to participate in such Distribution to the same extent
that the Holder would have participated therein if the Holder had held the number of shares of Common Stock acquirable upon complete exercise
of this Warrant (without regard to any limitations on exercise hereof, including without limitation, the Beneficial Ownership Limitation)
immediately before the date of which a record is taken for such Distribution, or, if no such record is taken, the date as of which the
record holders of shares of Common Stock are to be determined for the participation in such Distribution (provided, however,
to the extent that the Holder's right to participate in any such Distribution would result in the Holder exceeding the Beneficial Ownership
Limitation, then the Holder shall not be entitled to participate in such Distribution to such extent (or in the beneficial ownership of
any shares of Common Stock as a result of such Distribution to such extent) and the portion of such Distribution shall be held in abeyance
for the benefit of the Holder until such time, if ever, as its right thereto would not result in the Holder exceeding the Beneficial Ownership
Limitation).





 






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c)          Calculations.
All calculations under this Section 3 shall be made to the nearest cent or the nearest 1/100th of a share, as the case may be. For purposes
of this Section 3, the number of shares of Common Stock deemed to be issued and outstanding as of a given date shall be the sum of the
number of shares of Common Stock (excluding treasury shares, if any) issued and outstanding.


 


d)          Notice
to Holder.


 


i.          Adjustment
to Exercise Price. Whenever the Exercise Price is adjusted pursuant to any provision of this Section 3, the Company shall promptly
deliver to the Holder by facsimile or email a notice setting forth the Exercise Price after such adjustment and any resulting adjustment
to the number of Warrant Shares and setting forth a brief statement of the facts requiring such adjustment.


 


ii.         Notice
to Allow Exercise by Holder. If (A) the Company shall declare a dividend (or any other distribution in whatever form) on the Common
Stock, (B) the Company shall declare a special nonrecurring cash dividend on or a redemption of the Common Stock, (C) the Company shall
authorize the granting to all holders of the Common Stock rights or warrants to subscribe for or purchase any shares of capital stock
of any class or of any rights, (D) the approval of any stockholders of the Company shall be required in connection with any reclassification
of the Common Stock, any consolidation or merger to which the Company is a party, any sale or transfer of all or substantially all of
the assets of the Company, or any compulsory share exchange whereby the Common Stock is converted into other securities, cash or property,
or (E) the Company shall authorize the voluntary or involuntary dissolution, liquidation or winding up of the affairs of the Company,
then, in each case, the Company shall cause to be delivered by facsimile or email to the Holder at its last facsimile number or email
address as it shall appear upon the Warrant Register of the Company, at least 20 calendar days prior to the applicable record or effective
date hereinafter specified, a notice stating (x) the date on which a record is to be taken for the purpose of such dividend, distribution,
redemption, rights or warrants, or if a record is not to be taken, the date as of which the holders of the Common Stock of record to be
entitled to such dividend, distributions, redemption, rights or warrants are to be determined or (y) the date on which such reclassification,
consolidation, merger, sale, transfer or share exchange is expected to become effective or close, and the date as of which it is expected
that holders of the Common Stock of record shall be entitled to exchange their shares of the Common Stock for securities, cash or other
property deliverable upon such reclassification, consolidation, merger, sale, transfer or share exchange; provided that the failure to
deliver such notice or any defect therein or in the delivery thereof shall not affect the validity of the corporate action required to
be specified in such notice. To the extent that any notice provided in this Warrant constitutes, or contains, material, non-public information
regarding the Company or any of the Subsidiaries, the Company shall simultaneously file such notice with the Commission pursuant to a
Current Report on Form 8-K. The Holder shall remain entitled to exercise this Warrant during the period commencing on the date of such
notice to the effective date of the event triggering such notice except as may otherwise be expressly set forth herein.


 


 e)          
Other Adjustments:


 


i.                     As
to Warrant Shares and Exercise Price Regarding Subsequent Offering that includes Warrants. In the event that the Company closes
a registered public offering of its securities on or before six months from the date hereof that includes the issuance of warrants
to acquire common stock to the public investors in such offering (the “Subsequent Warrants”), then the Holder
shall have the right, but not the obligation, on a one-time basis, by signed written notice of election delivered to the Company in
accordance with the Purchase Agreement (the “Election Notice”), to elect to cause, with respect to the remaining
portion of this Warrant that has yet to be exercised, the related Warrant Shares and Exercise Price to be adjusted as follows:


 






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		(a)	The Exercise Price hereunder shall be adjusted to match the initial exercise price of the Subsequent Warrants;
and



 


		(b)	The remaining Warrant Shares shall be adjusted using the warrant coverage percentage used in calculating
the warrant shares under the Subsequent Warrants (the “Subsequent Coverage Percentage”), by multiplying the remaining Warrant
Shares by two (2) and then multiplying the product thereof by the Subsequent Coverage Percentage and rounding to the nearest whole share.



 


Such Election Notice
can only be exercised one-time and must be elected as to both adjustments (Exercise Price and Warrant Shares) collectively, so a Holder
cannot pick to adjust just one such feature as to the Subsequent Warrant. Such Election Notice must also be exercised in whole as to the
remaining portion of this Warrant that has not been exercised, and must be delivered to the Company within ten (10) days of the each earlier
of (i) the date the Company publicly announces the closing of the public offering, and (ii) the date that the Company notifies the Holder
in writing that such closing has taken place. Following such Election Notice being sent by the Holder in accordance herewith, the Exercise
Price and applicable Warrant Shares shall be deemed adjusted as provided above without any further act being required, and the Company
shall upon request of the Holder, deliver a statement to the Holder of the as-adjusted Warrant Shares and Exercise Price applicable to
this Warrant.


 


ii.                  
As to Warrant Shares Regarding Subsequent Offering that does not include Warrants. In the event that the Company closes
a registered public offering of its securities on or before six months from the date hereof that does not include the issuance of warrants
to acquire common stock to the public investors in such offering, and the per share purchase price paid by such public investors (“IPO
Price Per Share”) was less than the Per Share Purchase Price (as defined in the Purchase Agreement), then the Holder shall have
the right, but not the obligation, on a one-time basis, by signed written Election Notice delivered to the Company in accordance with
the Purchase Agreement, to elect to cause, with respect to the remaining portion of this Warrant that has yet to be exercised, the remaining
Warrant Shares shall be increased by the Warrant Share Increase Amount, which such term shall mean and be calculated as follows, with
all determinations made by the Board of Directors of the Company in its sole discretion in accordance with the below requirements:


 


		(a)	First, determine the difference between the Per Share Purchase Price (as defined in the Purchase Agreement)
and the purchase price per share paid by the public investors in the public offering, such difference the “Per Share Difference”;
then



		(b)	Second, determine the Black-Scholes value as of the time of the public offering closing of a warrant to
acquire one share of common stock (the “Per Share Warrant Value”) with a five year term and an exercise price equal to 150%
of the Per Share Purchase Price; then



		(c)	Third, divide the Per Share Difference by the Per Share Warrant Value, such quotient being the “Warrant
Adjustment Factor”); then



		(d)	Fourth, multiple the Warrant Adjustment Factor by the number of shares remaining under this Warrant that
have yet to be exercised, and the product thereof rounded up to the nearest whole share is the “Warrant Share Increase Amount”.



 






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Such Election Notice
can only be exercised one-time. Such Election Notice must also be exercised in whole as to the remaining portion of this Warrant that
has not been exercised, and must be delivered to the Company within ten (10) days of the each earlier of (i) the date the Company publicly
announces the closing of the public offering, and (ii) the date that the Company notifies the Holder in writing that such closing has
taken place. Following such Election Notice being sent by the Holder in accordance herewith, applicable Warrant Shares shall be deemed
adjusted as provided above without any further act being required, and the Company shall upon request of the Holder, deliver a statement
to the Holder of the as-adjusted Warrant Shares applicable to this Warrant.


 


Section 4.            Transfer
of Warrant.


 


a)          Transferability.
Subject to compliance with any applicable securities laws and the conditions set forth in Section 4(d) hereof and to the provisions set
forth in Section 4.1 of the Purchase Agreement, this Warrant and all rights hereunder are transferable, in whole or in part, upon surrender
of this Warrant at the principal office of the Company or its designated agent, together with a written assignment of this Warrant substantially
in the form attached hereto duly executed by the Holder or its agent or attorney and funds sufficient to pay any transfer taxes payable
upon the making of such transfer. Upon such surrender and, if required, such payment, the Company shall execute and deliver a new Warrant
or Warrants in the name of the assignee or assignees, as applicable, and in the denomination or denominations specified in such instrument
of assignment, and shall issue to the assignor a new Warrant evidencing the portion of this Warrant not so assigned, and this Warrant
shall promptly be cancelled. Notwithstanding anything herein to the contrary, the Holder shall not be required to physically surrender
this Warrant to the Company unless the Holder has assigned this Warrant in full, in which case, the Holder shall surrender this Warrant
to the Company within three (3) Trading Days of the date the Holder delivers an assignment form to the Company assigning this Warrant
full. The Warrant, if properly assigned in accordance herewith, may be exercised by a new holder for the purchase of Warrant Shares without
having a new Warrant issued.


 


b)          New
Warrants. This Warrant may be divided or combined with other Warrants upon presentation hereof at the aforesaid office of the Company,
together with a written notice specifying the names and denominations in which new Warrants are to be issued, signed by the Holder or
its agent or attorney. Subject to compliance with Section 4(a), as to any transfer which may be involved in such division or combination,
the Company shall execute and deliver a new Warrant or Warrants in exchange for the Warrant or Warrants to be divided or combined in accordance
with such notice. All Warrants issued on transfers or exchanges shall be dated the Issue Date and shall be identical with this Warrant
except as to the number of Warrant Shares issuable pursuant thereto.


 


c)          Warrant
Register. The Company shall register this Warrant, upon records to be maintained by the Company for that purpose (the “Warrant
Register”), in the name of the record Holder hereof from time to time. The Company may deem and treat the registered Holder
of this Warrant as the absolute owner hereof for the purpose of any exercise hereof or any distribution to the Holder, and for all other
purposes, absent actual notice to the contrary.


 


d)          Transfer
Restrictions. If, at the time of the surrender of this Warrant in connection with any transfer of this Warrant, the transfer of this
Warrant shall not be either (i) registered pursuant to an effective registration statement under the Securities Act and under applicable
state securities or blue sky laws or (ii) eligible for resale without volume or manner-of-sale restrictions or current public information
requirements pursuant to Rule 144, the Company may require, as a condition of allowing such transfer, that the Holder or transferee of
this Warrant, as the case may be, comply with the provisions set forth in Section 4.1 and Section 5.6 of the Purchase Agreement.


 


e)          Representation
by the Holder. The Holder, by the acceptance hereof, represents and warrants that it is acquiring this Warrant and, upon any
exercise hereof, will acquire the Warrant Shares issuable upon such exercise, for its own account and not with a view to or for
distributing or reselling such Warrant Shares or any part thereof in violation of the Securities Act or any applicable state
securities law, except pursuant to sales registered or exempted under the Securities Act.


 






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Section 5.            Miscellaneous.


 


a)          No
Rights as Stockholder Until Exercise. This Warrant does not entitle the Holder to any voting rights, dividends or other rights as
a stockholder of the Company prior to the exercise hereof as set forth in Section 2(c)(i), except as expressly set forth in Section 3.


 


b)          Loss,
Theft, Destruction or Mutilation of Warrant. The Company covenants that upon receipt by the Company of evidence reasonably satisfactory
to it of the loss, theft, destruction or mutilation of this Warrant or any stock certificate relating to the Warrant Shares, and in case
of loss, theft or destruction, of indemnity or security reasonably satisfactory to it (which, in the case of the Warrant, shall not include
the posting of any bond), and upon surrender and cancellation of such Warrant or stock certificate, if mutilated, the Company will make
and deliver a new Warrant or stock certificate of like tenor and dated as of such cancellation, in lieu of such Warrant or stock certificate.


 


c)          Saturdays,
Sundays, Holidays, etc. If the last or appointed day for the taking of any action or the expiration of any right required or granted
herein shall not be a Business Day, then, such action may be taken or such right may be exercised on the next succeeding Business Day.


 


d)          Authorized
Shares.


 


The Company covenants
that, during the period the Warrant is outstanding, it will reserve from its authorized and unissued Common Stock a sufficient number
of shares to provide for the issuance of the Warrant Shares upon the exercise of any purchase rights under this Warrant. The Company further
covenants that its issuance of this Warrant shall constitute full authority to its officers who are charged with the duty of issuing the
necessary Warrant Shares upon the exercise of the purchase rights under this Warrant. The Company will take all such reasonable action
as may be necessary to assure that such Warrant Shares may be issued as provided herein without violation of any applicable law or regulation,
or of any requirements of the Trading Market upon which the Common Stock may be listed. The Company covenants that all Warrant Shares
which may be issued upon the exercise of the purchase rights represented by this Warrant will, upon exercise of the purchase rights represented
by this Warrant and payment for such Warrant Shares in accordance herewith, be duly authorized, validly issued, fully paid and nonassessable
and free from all taxes, liens and charges created by the Company in respect of the issue thereof (other than taxes in respect of any
transfer occurring contemporaneously with such issue).


 


Except and to the
extent as waived or consented to by the Holder, the Company shall not by any action, including, without limitation, amending its certificate
of incorporation or through any reorganization, transfer of assets, consolidation, merger, dissolution, issue or sale of securities or
any other voluntary action, avoid or seek to avoid the observance or performance of any of the terms of this Warrant, but will at all
times in good faith assist in the carrying out of all such terms and in the taking of all such actions as may be necessary or appropriate
to protect the rights of Holder as set forth in this Warrant against impairment. Without limiting the generality of the foregoing, the
Company will (i) not increase the par value of any Warrant Shares above the amount payable therefor upon such exercise immediately prior
to such increase in par value, (ii) take all such action as may be necessary or appropriate in order that the Company may validly and
legally issue fully paid and nonassessable Warrant Shares upon the exercise of this Warrant and (iii) use commercially reasonable efforts
to obtain all such authorizations, exemptions or consents from any public regulatory body having jurisdiction thereof, as may be, necessary
to enable the Company to perform its obligations under this Warrant.


 


Before taking
any action which would result in an adjustment in the number of Warrant Shares for which this Warrant is exercisable or in the
Exercise Price, the Company shall obtain all such authorizations or exemptions thereof, or consents thereto, as may be necessary
from any public regulatory body or bodies having jurisdiction thereof.


 






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e)          Jurisdiction.
All questions concerning the construction, validity, enforcement and interpretation of this Warrant shall be determined in accordance
with the internal laws of the State of Delaware, without regard to the principles of conflicts of law thereof. Each party agrees that
all legal proceedings concerning the interpretations, enforcement and defense of the transactions contemplated by this Warrant (whether
brought against a party hereto or Holder or their respective affiliates, directors, officers, shareholders, partners, members, employees
or agents) shall be commenced exclusively in the state and federal courts sitting in the Commonwealth of Massachusetts. Each party hereby
irrevocably submits to the jurisdiction of the state and federal courts sitting in the Commonwealth of Massachusetts for the adjudication
of any dispute hereunder or in connection herewith or with any transaction contemplated hereby or discussed herein, and hereby irrevocably
waives, and agrees not to assert in any action or proceeding, any claim that it is not personally subject to the jurisdiction of any such
court, that such action or proceeding is improper or is an inconvenient venue for such proceeding.


 


f)          Restrictions.
The Holder acknowledges that the Warrant Shares acquired upon the exercise of this Warrant, if not registered, will have restrictions
upon resale imposed by state, federal or other applicable securities laws.


 


g)          Nonwaiver
and Expenses. No course of dealing or any delay or failure to exercise any right hereunder on the part of Holder shall operate as
a waiver of such right or otherwise prejudice the Holder’s rights, powers or remedies, notwithstanding the fact that all rights
hereunder terminate on the Termination Date. If the Company willfully and knowingly fails to comply with any provision of this Warrant,
which results in any material damages to the Holder, the Company shall pay to the Holder such amounts as shall be sufficient to cover
any costs and expenses including, but not limited to, reasonable attorneys’ fees, including those of appellate proceedings, incurred
by the Holder in collecting any amounts due pursuant hereto or in otherwise enforcing any of its rights, powers or remedies hereunder.


 


h)          Notices.
Any notice, request or other document required or permitted to be given or delivered to the Holder by the Company shall be delivered in
accordance with the notice provisions of the Purchase Agreement.


 


i)          Limitation
of Liability. No provision hereof, in the absence of any affirmative action by the Holder to exercise this Warrant to purchase Warrant
Shares, and no enumeration herein of the rights or privileges of the Holder, shall give rise to any liability of the Holder for the purchase
price of any Common Stock or as a stockholder of the Company, whether such liability is asserted by the Company or by creditors of the
Company.


 


j)          Remedies.
The Holder, in addition to being entitled to exercise all rights granted by law, including recovery of damages, will be entitled to specific
performance of its rights under this Warrant. The Company agrees that monetary damages would not be adequate compensation for any loss
incurred by reason of a breach by it of the provisions of this Warrant and hereby agrees to waive and not to assert the defense in any
action for specific performance that a remedy at law would be adequate.


 


k)          Successors
and Assigns. Subject to applicable securities laws, this Warrant and the rights and obligations evidenced hereby shall inure to the
benefit of and be binding upon the successors and permitted assigns of the Company and the successors and permitted assigns of Holder.
The provisions of this Warrant are intended to be for the benefit of any Holder from time to time of this Warrant and shall be enforceable
by the Holder or holder of Warrant Shares.


 


l)          Amendment.
This Warrant may be modified or amended or the provisions hereof waived with the written consent of the Company and the Holder.


 


m)         Severability.
Wherever possible, each provision of this Warrant shall be interpreted in such manner as to be effective and valid under applicable
law, but if any provision of this Warrant shall be prohibited by or invalid under applicable law, such provision shall be
ineffective to the extent of such prohibition or invalidity, without invalidating the remainder of such provisions or the remaining
provisions of this Warrant.


 






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n)          Headings.
The headings used in this Warrant are for the convenience of reference only and shall not, for any purpose, be deemed a part of this Warrant.


 


********************


 


(Signature Page Follows)


  









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IN WITNESS WHEREOF, the Company
has caused this Warrant to be executed by its officer thereunto duly authorized as of the date first above indicated.


  


	 	Biostage, Inc.
	 	 	 
	 	By:	 
	 	 	Name: David Green
	 	 	Title:   Interim CEO





 






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NOTICE OF EXERCISE


 


To: Biostage, Inc.







 


(1)   The undersigned
hereby elects to purchase ________ Warrant Shares of the Company pursuant to the terms of the attached Warrant (only if exercised in full),
and tenders herewith payment of the exercise price in full, together with all applicable transfer taxes, if any.


 


(2)   Payment
shall take the form of lawful money of the United States.


 


 


(3)   Please
issue said Warrant Shares in the name of the undersigned or in such other name as is specified below:


 


	 	 


 


The Warrant Shares shall be delivered to the following
DWAC Account Number:


 


	 	 
	 	 
	 	 
	 	 
	 	 


 


(4)   Accredited
Investor. The undersigned is an “accredited investor” as defined in Regulation D promulgated under the Securities Act
of 1933, as amended.


 


[SIGNATURE
OF HOLDER]


 


	Name of Investing Entity:	 
	 	 
	Signature of Authorized Signatory of Investing Entity:  	 
	Name of Authorized Signatory:	 
	Title of Authorized Signatory:	 
	 	 
	Date:	 





 






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ASSIGNMENT FORM


 


(To assign the foregoing Warrant, execute this
form and supply required information. Do not use this form to purchase shares.)


 


FOR VALUE RECEIVED, the foregoing Warrant and
all rights evidenced thereby are hereby assigned to


 


	Name:	 	 
	 	(Please Print)	 
	 	 	 
	Address:	 	 
	 	(Please Print)	 
	 	 	 
	Phone Number:	 	 
	 	 	 
	Email Address: 	 	 


 


Dated: _______________ __, ______


 


Holder’s Signature:___________________________________


 


Holder’s Address: ___________________________________


 






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