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Exhibit 10.2

NEITHER THIS SECURITY NOR THE SECURITIES INTO 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 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. THESE SECURITIES AND THE SECURITIES ISSUABLE UPON EXERCISE OF THESE
SECURITIES MAY BE PLEDGED IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT SECURED
BY SUCH SECURITIES.

COMMON STOCK PURCHASE WARRANT

To Purchase                        Shares of Common Stock of

GTC Biotherapeutics, Inc.

        This Common Stock Purchase Warrant (this "Warrant") certifies that, for
value received,                        and any permitted assignee (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
August 1, 2003 (the "Initial Exercise Date") and on or prior to the close of
business on the fifth anniversary of the Initial Exercise Date (the "Termination
Date") but not thereafter, to subscribe for and purchase from GTC
Biotherapeutics, Inc., a corporation incorporated in the Commonwealth of
Massachusetts (the "Company"), up to                        shares (the "Warrant
Shares") of the Company's Common Stock, par value $0.01 per share (the "Common
Stock"). The purchase price of one share of Common Stock (the "Exercise Price")
under this Warrant shall be $3.30, subject to adjustment hereunder. The Exercise
Price and the number of Warrant Shares for which the Warrant is exercisable
shall be subject to adjustment as provided herein. 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 July 30,
2003, between the Company and the purchasers signatory thereto.

        1.    Title to Warrant.    Prior to the Termination Date and subject to
compliance with applicable laws and to the conditions set forth in Section 7(d)
hereof and to the provisions of Section 2 of the Purchase Agreement, this
Warrant and all rights hereunder are transferable, in whole or in part, at the
office or agency of the Company by the Holder in person or by duly authorized
attorney, upon surrender of this Warrant together with the Assignment Form
annexed hereto properly endorsed. The transferee shall sign an investment letter
in form and substance reasonably satisfactory to the Company.

        2.    Authorization of Shares.    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, be duly authorized, validly issued, fully paid and nonassessable and
free from all taxes, liens and charges in respect of the issue thereof (other
than taxes in respect of any transfer occurring contemporaneously with such
issue).

        3.    Exercise of Warrant.    

        (a)   Except as provided elsewhere herein, exercise of the purchase
rights represented by this Warrant may be made at any time or times on or after
the Initial Exercise Date and on or before the Termination Date by the surrender
of this Warrant and the Notice of Exercise Form annexed hereto duly executed, at
the office of 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
such Holder appearing on the books of the Company) and upon payment of the
Exercise Price of the shares thereby purchased by

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wire transfer or cashier's check drawn on a United States bank or by means of a
cashless exercise pursuant to Section 3(c), the Holder shall be entitled to
receive a certificate for the number of Warrant Shares so purchased. This
Warrant shall be deemed to have been exercised and such certificate or
certificates shall be deemed to have been issued, and Holder or any other person
so designated to be named therein shall be deemed to have become a holder of
record of such shares for all purposes, as of the date the Warrant has been
exercised by payment to the Company of the Exercise Price and all taxes required
to be paid by the Holder, if any, pursuant to Section 5 prior to the issuance of
such shares, have been paid.

        (b)   If this Warrant shall have been exercised in part, the Company
shall, at the time of delivery of the certificate or certificates representing
Warrant Shares, deliver to Holder a new Warrant evidencing the rights of 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.

        (c)   If after the Effectiveness Deadline (as such term is defined in
the Registration Rights Agreement attached as an Exhibit to the Purchase
Agreement (the "Registration Rights Agreement")) (i) a Registration Statement
has not been declared effective by the Commission registering the sale of the
Warrant Shares to the Holder (or alternatively, the resale of the Warrant Shares
by the Holder), or (ii) after the date first declared effective by the
Commission but prior to the expiration of the Registration Period, as such term
is defined in the Registration Rights Agreement, the Registration Statement
ceases to be effective and available to register the sale of the Warrant Shares
to the Holder (or alternatively, the resale of the Warrant Shares by the Holder)
for a total of Twenty Five (25) Trading Days in the aggregate, then until such
Registration Statement has been declared effective or for so long as it ceases
to be available for more than a total of Twenty Five (25) Trading Days in the
aggregate, as the case may be, this Warrant may also be exercised at such time
by means of a "cashless exercise" in which the Holder shall be entitled to
receive a certificate for the number of Warrant Shares equal to the quotient
obtained by dividing [(A-B) (X)] by (A), where:

(A) – the VWAP on the trading day preceding the date of such election;

(B) – the Exercise Price of the Warrants, as adjusted; and

(X) – the number of Warrant Shares issuable upon exercise of the Warrants in
accordance with the terms of this Warrant.

For purposes of this Warrant, "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 the American Stock Exchange, the New York Stock
Exchange, the Nasdaq National Market or the Nasdaq SmallCap Market (each a
"Principal Market"), the daily volume weighted average price of the Common Stock
for such date (or the nearest preceding date) on the Principal Market on which
the Common Stock is then listed or quoted as reported by Bloomberg Financial
L.P. (based on a trading day from 9:30 a.m. Eastern Time to 4:02 p.m. Eastern
Time); (b) if the Common Stock is not then listed or quoted on a Principal
Market and if prices for the Common Stock are then quoted on the OTC Bulletin
Board (or any successor market), the volume weighted average price of the Common
Stock for such date (or the nearest preceding date) on the OTC Bulletin Board
(or any successor market); (c) if the Common Stock is not then listed or quoted
on the OTC Bulletin Board (or any successor market) and if prices for the Common
Stock are then reported in the "Pink Sheets" published by the National Quotation
Bureau Incorporated (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 a nationally recognized-independent
appraiser selected in good faith by the Company.

        4.    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 Holder would

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otherwise be entitled to purchase upon such exercise, the Company shall pay a
cash adjustment in respect of such final fraction in an amount equal to such
fraction multiplied by the Exercise Price.

        5.    Charges, Taxes and Expenses.    Issuance of certificates for
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 such
certificate, all of which taxes and expenses shall be paid by the Company, and
such certificates 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
certificates for 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.

        6.    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.

        7.    Transfer, Division and Combination.    

        (a)   Subject to compliance with any applicable securities laws and the
conditions set forth in Sections 1 and 7(d) hereof and to the provisions of
Section 2 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, 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 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. A Warrant, if properly assigned, may be
exercised by a new holder for the purchase of Warrant Shares without having a
new Warrant issued.

        (b)   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 7(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.

        (c)   The Company shall prepare, issue and deliver at its own expense
(other than transfer taxes) the new Warrant or Warrants under this Section 7.

        (d)   The Company agrees to maintain, at its aforesaid office, books for
the registration and the registration of transfer of the Warrants.

        (e)   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
registered pursuant to an effective registration statement under the Securities
Act and under applicable state securities or blue sky laws, the Company may
require, as a condition of allowing such transfer (i) that the Holder or
transferee of this Warrant, as the case may be, furnish to the Company a written
opinion of counsel (which opinion shall be in form, substance and scope
customary for opinions of counsel in comparable transactions) to the effect that
such transfer may be made without registration under the Securities Act and
under applicable state securities or blue sky laws, (ii) that the Holder or
transferee execute and deliver to the Company an investment letter in form and
substance acceptable to the Company and (iii) that the transferee be an
"accredited investor" as defined in Rule 501(a) promulgated under the Securities
Act.

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        8.    No Rights as Shareholder until Exercise.    This Warrant does not
entitle the Holder to any voting rights or other rights as a shareholder of the
Company prior to the exercise hereof. Upon the surrender of this Warrant and the
payment of the aggregate Exercise Price (or if permitted hereunder, by means of
a cashless exercise), the Warrant Shares so purchased shall be and be deemed to
be issued to such Holder as the record owner of such shares as of the close of
business on the later of the date of such surrender or payment.

        9.    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.

        10.    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 be a Saturday, Sunday or a legal holiday, then such action
may be taken or such right may be exercised on the next succeeding day not a
Saturday, Sunday or legal holiday.

        11.    Adjustments of Exercise Price and Number of Warrant
Shares.    The number and kind of securities purchasable upon the exercise of
this Warrant and the Exercise Price shall be subject to adjustment from time to
time upon the happening of any of the following. In case the Company shall
(i) pay a dividend in shares of Common Stock or make a distribution in shares of
Common Stock to holders of its outstanding Common Stock, (ii) subdivide its
outstanding shares of Common Stock into a greater number of shares,
(iii) combine its outstanding shares of Common Stock into a smaller number of
shares of Common Stock, or (iv) issue any shares of its capital stock in a
reclassification of the Common Stock, then the number of Warrant Shares
purchasable upon exercise of this Warrant immediately prior thereto shall be
adjusted so that the Holder shall be entitled to receive the kind and number of
Warrant Shares or other securities of the Company which it would have owned or
have been entitled to receive had such Warrant been exercised in advance
thereof. Upon each such adjustment of the kind and number of Warrant Shares or
other securities of the Company which are purchasable hereunder, the Holder
shall thereafter be entitled to purchase the number of Warrant Shares or other
securities resulting from such adjustment at an Exercise Price per Warrant Share
or other security obtained by multiplying the Exercise Price in effect
immediately prior to such adjustment by the number of Warrant Shares purchasable
pursuant hereto immediately prior to such adjustment, and dividing such product
by the number of Warrant Shares or other securities of the Company resulting
from such adjustment. An adjustment made pursuant to this paragraph shall become
effective immediately after the effective date of such event retroactive to the
record date, if any, for such event.

        12.    Reorganization, Reclassification, Merger, Consolidation or
Disposition of Assets.    In case the Company shall reorganize its capital,
reclassify its capital stock, consolidate or merge with or into another
corporation (where the Company is not the surviving corporation or where there
is a change in or distribution with respect to the Common Stock of the Company),
or sell, transfer or otherwise dispose of all or substantially all its property,
assets or business to another corporation and, pursuant to the terms of such
reorganization, reclassification, merger, consolidation or disposition of
assets, shares of common stock of the successor or acquiring corporation, or any
cash, shares of stock or other securities or property of any nature whatsoever
(including warrants or other subscription or purchase rights) in addition to or
in lieu of common stock of the successor or acquiring corporation ("Other
Property"), are to be received by or distributed to the holders of Common Stock
of the Company, then the Holder shall have the right thereafter to receive upon
exercise of this Warrant, the number of shares of Common Stock of the successor
or acquiring corporation or of the Company, if it is the surviving corporation,
and Other Property receivable upon or as a result of such reorganization,

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reclassification, merger, consolidation or disposition of assets by a Holder of
the number of shares of Common Stock for which this Warrant is exercisable
immediately prior to such event. In case of any such reorganization,
reclassification, merger, consolidation or disposition of assets, the successor
or acquiring corporation (if other than the Company) shall expressly assume the
due and punctual observance and performance of each and every covenant and
condition of this Warrant to be performed and observed by the Company and all
the obligations and liabilities hereunder, subject to such modifications as may
be deemed appropriate (as determined in good faith by resolution of the Board of
Directors of the Company) in order to provide for adjustments of Warrant Shares
for which this Warrant is exercisable which shall be as nearly equivalent as
practicable to the adjustments provided for in this Section 12. For purposes of
this Section 12, "common stock of the successor or acquiring corporation" shall
include stock of such corporation of any class which is not preferred as to
dividends or assets over any other class of stock of such corporation and which
is not subject to redemption and shall also include any evidences of
indebtedness, shares of stock or other securities which are convertible into or
exchangeable for any such stock, either immediately or upon the arrival of a
specified date or the happening of a specified event and any warrants or other
rights to subscribe for or purchase any such stock. The foregoing provisions of
this Section 12 shall similarly apply to successive reorganizations,
reclassifications, mergers, consolidations or disposition of assets.

        13.    Limitation on Exercise.    Notwithstanding anything to the
contrary contained herein, the number of shares of Common Stock that may be
acquired by the Holder upon any exercise of this Warrant (or otherwise in
respect hereof) shall be limited to the extent necessary to insure that,
following such exercise (or other issuance), the total number of shares of
Common Stock then beneficially owned by such Holder and its Affiliates and any
other Persons whose beneficial ownership of Common Stock would be aggregated
with the Holder's for purposes of Section 13(d) of the Exchange Act, does not
exceed 9.999% of the total number of issued and outstanding shares of Common
Stock (including for such purpose the shares of Common Stock issuable upon such
exercise). For such purposes, beneficial ownership shall be determined in
accordance with Section 13(d) of the Exchange Act and the rules and regulations
promulgated thereunder. Each delivery of an Exercise Notice hereunder will
constitute a representation by the Holder that it has evaluated the limitation
set forth in this paragraph and determined that issuance of the full number of
Warrant Shares requested in such Exercise Notice is permitted under this
paragraph. This provision shall not restrict the number of shares of Common
Stock which a Holder may receive or beneficially own in order to determine the
amount of securities or other consideration that such Holder may receive in the
event of a merger or other business combination or reclassification involving
the Company as contemplated in Section 12 of this Warrant. This restriction may
not be waived without the consent of the Holder.

        14.    Voluntary Adjustment by the Company.    The Company may at any
time during the term of this Warrant reduce the then current Exercise Price to
any amount and for any period of time deemed appropriate by the Board of
Directors of the Company.

        15.    Notice of Adjustment.    Whenever the number of Warrant Shares or
number or kind of securities or other property purchasable upon the exercise of
this Warrant or the Exercise Price is adjusted, as herein provided, the Company
shall give notice thereof to the Holder, which notice shall state the number of
Warrant Shares (and other securities or property) purchasable upon the exercise
of this Warrant and the Exercise Price of such Warrant Shares (and other
securities or property) after such adjustment, setting forth a brief statement
of the facts requiring such adjustment and setting forth the computation by
which such adjustment was made.

        16.    Notice of Corporate Action.    If at any time: (a) the Company
shall take a record of the holders of its Common Stock for the purpose of
entitling them to receive a dividend or other distribution, or any right to
subscribe for or purchase any evidences of its indebtedness, any shares of stock
of any class or any other securities or property, or to receive any other right,
or (b) there shall be any capital reorganization of the Company, any
reclassification or recapitalization of the capital stock

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of the Company or any consolidation or merger of the Company with, or any sale,
transfer or other disposition of all or substantially all the property, assets
or business of the Company to, another corporation or, (c) there shall be a
voluntary or involuntary dissolution, liquidation or winding up of the Company;
then, in any one or more of such cases, the Company shall give to Holder (i) at
least 20 days' prior written notice of the date on which a record date shall be
selected for such dividend, distribution or right or for determining rights to
vote in respect of any such reorganization, reclassification, merger,
consolidation, sale, transfer, disposition, liquidation or winding up, and
(ii) in the case of any such reorganization, reclassification, merger,
consolidation, sale, transfer, disposition, dissolution, liquidation or winding
up, at least 20 days' prior written notice of the date when the same shall take
place. Such notice in accordance with the foregoing clause also shall specify
(i) the date on which any such record is to be taken for the purpose of such
dividend, distribution or right, the date on which the holders of Common Stock
shall be entitled to any such dividend, distribution or right, and the amount
and character thereof, and (ii) the date on which any such reorganization,
reclassification, merger, consolidation, sale, transfer, disposition,
dissolution, liquidation or winding up is to take place and the time, if any
such time is to be fixed, as of which the holders of Common Stock shall be
entitled to exchange their Warrant Shares for securities or other property
deliverable upon such disposition, dissolution, liquidation or winding up. Each
such written notice shall be sufficiently given if addressed to Holder at the
last address of Holder appearing on the books of the Company and delivered in
accordance with Section 17(d).

        17.    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
executing stock certificates to execute and issue the necessary certificates for
the 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 Principal Market
upon which the Common Stock may be listed at such time.

        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
articles of organization 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 (a) 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, (b) 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 (c) 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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        18.    Miscellaneous.    

        (a)    Jurisdiction.    All questions concerning the construction,
validity, enforcement and interpretation of this Warrant shall be governed by
the internal laws of the State of New York, without giving effect to any choice
of law or conflict of law provision or rule (whether of the State of New York or
any other jurisdictions) that would cause the application of the laws of any
jurisdictions other than the State of New York. Each party hereby irrevocably
submits to the non-exclusive jurisdiction of the state and federal courts
sitting in the City of New York, Borough of Manhattan, 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 suit, action or proceeding, any claim that it is not
personally subject to the jurisdiction of any such court, that such suit, action
or proceeding is brought in an inconvenient forum or that the venue of such
suit, action or proceeding is improper. Each party hereby irrevocably waives
personal service of process and consents to process being served in any such
suit, action or proceeding by mailing a copy thereof to such party at the
address for such notices to it under this Warrant and agrees that such service
shall constitute good and sufficient service of process and notice thereof. EACH
PARTY HEREBY IRREVOCABLY WAIVES ANY RIGHT IT MAY HAVE, AND AGREES NOT TO
REQUEST, A JURY TRIAL FOR THE ADJUDICATION OF ANY DISPUTE HEREUNDER OR IN
CONNECTION HEREWITH OR ARISING OUT OF THIS WARRANT OR ANY TRANSACTION
CONTEMPLATED HEREBY.

        (b)    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 and federal securities laws.

        (c)    Nonwaiver.    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 Holder's rights, powers or remedies,
notwithstanding all rights hereunder terminate on the Termination Date.

        (d)    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.

        (e)    Limitation of Liability.    No provision hereof, in the absence
of any affirmative action by Holder to exercise this Warrant or purchase Warrant
Shares, and no enumeration herein of the rights or privileges of Holder, shall
give rise to any liability of 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.

        (f)    Remedies.    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 the defense in any action for specific performance that a remedy at law
would be adequate.

        (g)    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 of the Company and the successors
and permitted assigns of Holder. The provisions of this Warrant are intended to
be for the benefit of all Holders from time to time of this Warrant and shall be
enforceable by any such Holder or holder of Warrant Shares.

        (h)    Amendment.    Except as provided in Section 13, this Warrant may
be modified or amended or the provisions hereof waived with the written consent
of the Company and the holders of Warrants issued under the Purchase Agreement
representing a majority of the Warrant Shares issuable under Warrants then
outstanding as of the date such consent is sought.

        (i)    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.

        (j)    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.

        (k)    Acceptance.    Receipt of this Warrant by the Holder shall
constitute acceptance of and agreement to all of the terms and conditions
contained herein.

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        IN WITNESS WHEREOF, the Company has caused this Warrant to be executed
by its officer thereunto duly authorized.

Dated: August 1, 2003

    GTC BIOTHERAPEUTICS, INC.
 
 
By:
 

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John B. Green
Senior Vice President, Chief Financial Officer and Treasurer

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NOTICE OF EXERCISE

To: GTC Biotherapeutics, Inc.

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

        (2)   Payment shall take the form of (check applicable box):

olawful money of the United States; or

othe cancellation of such number of Warrant Shares as is necessary, in
accordance with the formula set forth in subsection 3(c), to exercise this
Warrant with respect to the maximum number of Warrant Shares purchasable
pursuant to the cashless exercise procedure set forth in subsection 3(c).

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

 
 

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The Warrant Shares shall be delivered to the following:

 
 

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

    [PURCHASER]
 
 
By:
 

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    Name:
Title:    
 
 
Dated:
 

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ASSIGNMENT FORM

for

Common Stock Purchase Warrant
of GTC Biotherapeutics, Inc.

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

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

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whose address is

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Dated:
 

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Holder's Signature:
 

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Holder's Address:
 

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Signature Guaranteed:
 

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        NOTE: The signature to this Assignment Form must correspond with the
name as it appears on the face of the Warrant, without alteration or enlargement
or any change whatsoever, and must be guaranteed by a bank or trust company.
Officers of corporations and those acting in a fiduciary or other representative
capacity should file proper evidence of authority to assign the foregoing
Warrant.

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QuickLinks

Exhibit 10.2

NOTICE OF EXERCISE
ASSIGNMENT FORM for Common Stock Purchase Warrant of GTC Biotherapeutics, Inc.
(To assign the foregoing Warrant, execute this form and supply required
information. Do not use this form to exercise the warrant.)