EXHIBIT 10.21

Confidential material omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote such omissions.

MASTER AGREEMENT RELATING TO THE PRODUCTION

OF CLARIFIED

GOAT’S MILK CONTAINING

RECOMBINANT HUMAN ALPHA FETOPROTEIN

BY AND BETWEEN

GTC BIOTHERAPEUTICS, INC.

AND

MERRIMACK PHARMACEUTICALS, INC.

September 9, 2005

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THIS AGREEMENT (the “Master Agreement”) is made this 9th day of September, 2005
(the “Effective Date”), by and between Merrimack Pharmaceuticals, Inc., a
Massachusetts corporation (“Merrimack”) located at 101 Binney Street, Cambridge,
MA 02142 and GTC Biotherapeutics, Inc., a Massachusetts corporation (“GTC”)
located at 175 Crossing Boulevard, Framingham, MA 01702. (GTC and Merrimack each
individually a “Party” and collectively the “Parties”).

WHEREAS, Merrimack is a biotechnology company actively involved in the
development of recombinant human alpha fetoprotein); and

WHEREAS, GTC is a leader in the development of therapeutic proteins in the milk
of transgenic animals; and

WHEREAS, on May 11, 1999, Merrimack (then known as Atlantic Biopharmaceuticals,
Inc.) and GTC entered into an agreement under which GTC was to conduct a mouse
feasibility study of human alpha fetoprotein (the “May 1999 Agreement”); and

WHEREAS, on February 12, 2001, Merrimack and GTC entered into an agreement for
the generation of goats transgenic for human alpha fetoprotein expressed in milk
(the “February 2001 Agreement” and together with the May 1999 Agreement, the
“Initial Agreements”); and

WHEREAS, on June 27, 2003, in order to more fully exploit the opportunities for
the commercialization of Transgenic rhAFP, Merrimack and GTC entered into the
first definitive (Stage I) agreement for the purpose of producing Transgenic
rhAFP in the milk of transgenic animals for Merrimack’s use in pre-clinical
studies, clinical trials and commercial distribution, to be implemented in three
stages through a series of definitive agreements between the Parties (the “2003
Agreement”); and

WHEREAS, the 2003 Agreement has been successfully completed to the satisfaction
of the Parties, and the Parties wish to enter into this Master Agreement to
provide for continued production of Transgenic rhAFP (as defined below); and

WHEREAS, the Parties agree that during the term of this Master Agreement the
production of any Transgenic rhAFP in the milk or other bodily fluids or tissue
of transgenic animals by or on behalf of Merrimack or its Affiliates, will be
done exclusively by GTC pursuant to this Master Agreement.

NOW THEREFORE, in consideration of the premises and agreements herein contained,
and intending to be bound hereby, the Parties hereto hereby agree as set forth
below.

 

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1. Definitions. For purposes of this Master Agreement the following terms shall
have the meaning set forth below:

 

“Affiliate”

   Shall mean any corporation that controls, is controlled by, or is under
common control with a Party hereto. A corporation shall be regarded as in
control of another corporation if it owns or directly or indirectly controls at
least fifty (50%) of the voting stock of the other corporation, or in the
absence of the ownership of at least fifty percent (50%) of the voting stock, if
it possesses, directly or indirectly, the power to direct or cause the direction
of the management and policies of the corporation. “Ancillary Agreements”   
Means the 2003 Agreement, the Maintenance Agreement, Quality Agreement,
Manufacturing Service Agreement and Lease Agreement, each dated as of the
Effective Date, between the Parties relating to the subject matter hereof, and
any other agreements which the Parties may from time to time enter into
referring to this Master Agreement and relating to the subject matter hereof.
“Biopharmaceutical”    Means any medicinal drug, therapeutic, vaccine or any
medically useful composition whose origin, synthesis, or manufacture involves
the use of microorganisms, recombinant animals (including, without limitation,
chimeric or transgenic animals), nuclear transfer, microinjection, or cell
culture techniques. “Business Day”    Shall mean any day on which the banks are
open for commercial banking business in the Commonwealth of Massachusetts. “Cell
Lines”    Shall mean the transfected cells used for the development of the
transgenic Founder Goats and containing the DNA sequence encoding Transgenic
rhAFP and/or the cells derived from tissue samples from a transgenic goat
containing the DNA sequence encoding Transgenic rhAFP. “Change in Control”   
Shall mean (i) the acquisition of ownership, directly or indirectly,
beneficially or of record, by any person or group (within the meaning of the
Securities Exchange Act of 1934, as amended, and the rules of the Securities and
Exchange Commission thereunder as in effect on the date hereof), of shares
representing more than 50% of the aggregate ordinary voting power represented by
the issued and outstanding capital stock of GTC, (ii) a merger or similar
combination after which 50% or more of the voting stock of the surviving
corporation is held by persons who were not stockholders of GTC immediately
prior to such merger or combination

 

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   (iii) occupation of a majority of the seats on the Board of Directors of GTC
by persons who were neither (A) nominated by the independent Directors of GTC or
a committee thereof (as determined pursuant to the rules of the securities
exchange on which GTC’s shares, as then in effect) are listed nor (B) appointed
by directors so nominated, or (iii) the acquisition of the power to directly or
indirectly direct or cause the direction of the management or policies of GTC,
whether through the ability to exercise voting power, by contract or otherwise.

“Clarified Milk”

   Shall mean the milk of Transgenic Goats that contains Transgenic rhAFP and
that has been processed to remove particulates, excess casein micelles and
lipids allowing further processing to recover Transgenic rhAFP.

“Clarification Technology”

   Shall mean technology, methods or Know-How for purifying, treating,
crystallizing, filtering, clarifying, fractionating and/or concentrating the
milk of a transgenic animal to remove particulates, excess casein micelles and
lipids so as to enable the production of a Clarified Milk product containing
Transgenic rhAFP. This does not include the production of a recombinant protein
in the milk of a transgenic animal.

“Commercialization”

   Shall mean the date of first regulatory approval of Transgenic rhAFP in
either the United States or Europe.

“Know-How”

   Shall mean all technical information, unpatented inventions, manufacturing
secrets, practical experience, secret processes, formulae, manufacturing
procedures, methods and materials relating to the Field of Interest.

“Field of Interest”

   Shall mean the production of Transgenic rhAFP in a Clarified Milk product of
a transgenic animal and/or the means to process that Clarified Milk into a form
of Transgenic rhAFP useful as a pharmaceutical.

“GTC’s Transgenic Technology

   Shall mean GTC’s Intellectual Property and practices for the production of
recombinant proteins in the milk of transgenic animals and the development of
such animals, also included is enabling the production of a transgenic animal
such an animal being capable of producing a target recombinant protein in its
milk.

“Improvements”

   Shall mean any improvement, enhancement or modification of a product or
process described in a patent or patent application owned, controlled licensed
or assigned to one of the Parties.

“Invention”

   Includes any invention, discovery, work of authorship, software, information
or data, patentable or unpatentable, that is conceived,

 

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   developed or reduced to practice in the course of the services provided
pursuant to this Master Agreement or any Ancillary Agreement specifically
excluding, however, any of either Party’s pre-existing assays, techniques,
compositions, methods or processes. A “Patentable Invention” for purposes of
this Master Agreement is an Invention that passes the tests of the 1952 Patent
Code with regard to satisfying the key statutory legal tests of novelty, utility
and non-obviousness.

“Intellectual Property”

   Shall mean any patent or patent application, Know-How, development or other
Confidential Information, including but not limited to ideas, concepts,
unpatented inventions, trade secrets, drawings, designs, models, specifications,
formulae, data, processes, procedures and techniques.

“Transgenic rhAFP”

   Shall mean rhAFP produced using GTC’s Transgenic Technology.

“Transgenic rhAFP Product”

   Shall mean a pharmaceutical product sold by or on behalf of Merrimack the
active ingredient of which is Transgenic rhAFP.

“Net Revenue”

   Shall mean the gross amount received by Merrimack and/or its Affiliates from
the commercial sale of its Transgenic rhAFP Product to a person or entity or the
grant of rights to sell or distribute its Transgenic rhAFP. These amounts shall
include all royalty payments to Merrimack or its Affiliates, milestone payments
received by Merrimack or its Affiliates or any other payments received by
Merrimack (except for payments for research and development activities) less the
following:   

(i)     customary trade, quantity, or cash discounts to the extent actually
allowed and taken;

  

(ii)    amounts repaid or credited by reason of rejection or return;

  

(iii)  to the extent separately stated on purchase orders, invoices, or other
documents of sale, any taxes or other governmental charges levied on the
production, sale, transportation, delivery, or use of Transgenic rhAFP which is
paid by or on behalf of Merrimack; and

  

(iv)   outbound transportation costs prepaid or allowed and costs of insurance
in transit.

   Net Revenue may be received by Merrimack either before or after
Commercialization.    No deductions shall be made for commissions paid to
individuals whether they are with an independent sales agency or regularly
employed by Merrimack and on its payroll, or for cost of collections.

 

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   In the case of sales of a product that contains a Transgenic rhAFP Product
and at least one other essential functional component, (hereinafter,
“Combination Product”), Net Revenue mean the gross amount received by Merrimack
and its Affiliates on sales of the Combination Product, less the deductions set
forth above, multiplied by a pro-ration factor that is determined as follows:   

(i)     If all components of the Combination Product are sold separately, the
pro-ration factor shall be determined by the formula [A/(A+B)], where A is the
aggregate gross sales price of an Transgenic rhAFP product when sold separately
from all other essential functional components, and B is the aggregate gross
sales price of the other essential functional components when sold separately
from the Transgenic rhAFP; or

  

(ii)    If all components of the Combination Product are not sold separately,
the pro-ration factor shall be determined by the formula [V/(V+D)], where V is
the value of Transgenic rhAFP, and D is the value of the other essential
functional components, each being determined by agreement in good faith by
Merrimack and GTC.

“Net Partner Sales”    Shall mean the gross amount or any other payment received
by a Partner for the sale of Transgenic rhAFP Product to any person, firm or
entity other than Merrimack or an Affiliate of Merrimack or such Partner, less
the following:   

(i)     customary trade, quantity, or cash discounts to the extent actually
allowed and taken;

  

(ii)    amounts repaid or credited by reason of rejection or return;

  

(iii)  to the extent separately stated on purchase orders, invoices, or other
documents of sale, any taxes or other governmental charges levied on the ion,
sale, transportation, delivery, or use of Transgenic rhAFP Product which is paid
by or on behalf of such Partner; and

  

(iv)   outbound transportation costs prepaid or allowed and costs of insurance
in transit; and

 

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Confidential material omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote such omissions.

 

  

(v)    any transfer price payable to GTC or any of its Affiliates for the
purchase of Transgenic rhAFP Product by such Partner or any of its Affiliates.

   No deductions shall be made for commissions paid to individuals whether they
are with independent sales agencies or regularly employed by such Partner and on
its payroll, or for cost of collections.    In the case of a Combination
Product, Net Partner Sales shall be calculated in the same manner as is used to
calculate Net Revenues in connection with such Combination Product.

“Partner”

   Shall mean a firm or entity with a contractual relationship with Merrimack or
any of its Affiliates, which contractual relationship provides for the Partner
to market, sell or distribute Transgenic rhAFP Product anywhere in the world.

“Property”

   Shall mean GTC’s property located ************ Massachusetts.

“Purification Technology”

   Shall mean technology, Inventions, methods or Know-How for purifying
Transgenic rhAFP from Clarified Milk.

“rhAFP”

   Shall mean recombinant human non-glycosolated Alpha Fetoprotein.

“Transgenic Goats”

   Shall mean goats which carry the heterologous DNA encoding human alpha
fetoprotein.

“Valid Claim”

   Means with respect to the claim of a Patent Right licensed under this Master
Agreement, a claim that has not been held permanently invalid or otherwise
unenforceable by a court of competent jurisdiction whose holding is not
appealable or is not appealed within the time allowed for appeal.

2. Royalty Payments.

 

  2.1 Royalty. In further consideration of the rights granted and services
provided to it hereunder, Merrimack hereby agrees to make royalty payments to
GTC equal to a royalty rate initially set at ************ of Merrimack’s Net
Revenues, plus ************ of Net Partner Sales, subject to the other
provisions of this Section 2.

 

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Confidential material omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote such omissions.

 

  2.2 Investment. In exchange for a payment of ************ dollars ($USD) to
Merrimack by GTC, either in cash or forgiveness of indebtedness or in such
combination of goods and/or services as may be agreed by Merrimack and GTC,
prior to the Commercialization of Transgenic rhAFP, Merrimack will convert the
Royalty payable to GTC from ************ of Merrimack’s Net Revenues plus
************ Net Partner Sales to ************ of Net Partner Sales. GTC shall
have the right to make this payment in cash or forgiveness of indebtedness at
any time prior to Commercialization of Transgenic rhAFP: any payment of this
amount in goods and services (other than goods and services provided under this
Agreement shall be subject to Merrimack’s reasonable agreement regarding the
nature and value of such goods and/or services. Such nature and value shall be
made through a good faith determination by the Parties.

 

  2.3 Reporting. For each calendar quarter after Commercialization, Merrimack
shall deliver to GTC, within ************ business days after the end of each
calendar quarter, a written report setting forth Net Revenues and Net Partner
Sales of any Transgenic rhAFP Product during such calendar quarter, on a
country-by-country basis; provided that if Merrimack does not receive data from
its Partner regarding Net Partner Sales for any calendar quarter within
************ business days after the end of such quarter, such ************
business day period shall be extended to a date which is ************ business
days after Merrimack receives such data. Each such report shall also set forth
an explanation of the calculation of the royalties, if any, payable hereunder.

 

  2.4 Payment. Simultaneously with the delivery of each report required pursuant
to Section § 2.3 above, Merrimack shall tender payment in USD all royalties
shown to be due therein based on exchange rates then in effect. The basis for
determining the exchange rates in effect for the purposes of this Section § 2.4
shall be the “buy” rate for Dollars in such currency as published in the WALL
STREET JOURNAL on the Business Day immediately preceding the date such payment
is due.

 

  2.5 Blocked Payments. If by law, regulation, or fiscal policy of a particular
country, conversion into United States dollars or transfer of funds of a
convertible currency to USD is restricted or forbidden (“Blocked Payments”),
Merrimack shall give GTC prompt notice in writing and shall pay the Blocked
Payments through such means or methods as are lawful in such country as GTC may
reasonably designate. Failing the designation by GTC of such lawful means

 

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  2.6 or methods within thirty (30) days after such notice is given to GTC,
Merrimack shall deposit such Blocked Payments in local currency to the credit of
GTC in a recognized banking institution selected by Merrimack and identified in
a written notice to GTC, and such deposit shall fulfill all obligations of
Merrimack to GTC with respect to such Blocked Payments. So long as Merrimack
satisfies the provisions of this Section § 2.5, Merrimack shall not be
considered to have violated any of its payment obligations hereunder with
respect to any Blocked Payments.

 

  2.7 Taxes. Any and all withholding or similar taxes imposed or levied on
account of the receipt of royalties payable under this Master Agreement which
are required to be withheld by Merrimack shall be paid by Merrimack on behalf of
GTC and shall be paid to the proper taxing authority. Proof of payment shall be
secured and sent to the GTC by Merrimack as evidence of such payment in such
form as required by the tax authorities having jurisdiction over Merrimack. Such
taxes shall be deducted from the royalty that would otherwise be remittable by
Merrimack.

 

  2.8 Books and Records. Merrimack shall keep, and shall require all Affiliates
to keep, full, true and accurate books of accounts and other records containing
all information and data which may be necessary to ascertain and verify the
royalties payable hereunder relative to Transgenic rhAFP for a period of three
(3) years from the calendar quarter to which such books and records apply. For a
period of three (3) years from the calendar quarter to which such books and
records apply, GTC shall have the right from time to time (not to exceed once
during each calendar year) during normal business hours to have an independent
agent, accountant or other representative audit in confidence, such books,
records and supporting data. The cost of such audit shall be borne by GTC unless
it is established by the audit that there has been an error which has caused GTC
to receive less than it is due by five percent (5%) of more for the period under
audit, in which case the cost of such audit shall be borne by GTC.

3. Confidentiality

3.1 For a period of ten (10 ) years from the termination of this Master
Agreement, any Confidential Information (as defined below) disclosed by the
disclosing Party hereunder, directly or indirectly, to the receiving Party
hereunder, including information which forms the subject matter of this Master
Agreement which has been disclosed prior to the date hereof, shall be deemed
confidential, and shall not be disclosed by the receiving Party to third
Parties, except as set forth below. Access to such Confidential Information will
be limited to employees, agents, Affiliates (as defined

 

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below), consultants or contractors of the receiving Party who reasonably require
such Confidential Information and who are bound to the receiving Party by
similar obligations in respect of confidentiality and use. The receiving Party
will use such Confidential Information only to carry out its obligations or to
exercise its rights hereunder and will not use such Confidential Information for
its own benefit or for the benefit of others or in any way inconsistent with
this Master Agreement.

3.2 Nothing contained herein will in any way restrict or impair each Party’s
right to use, disclose or otherwise deal with any Confidential Information
which:

 

  3.2.1  at the time of disclosure, is in the public domain;

 

  3.2.2  after disclosure, becomes part of the public domain by publication or
otherwise, except by breach of this Master Agreement by the receiving Party;

 

  3.2.3  was demonstrably in the receiving Party’s possession at the time of
such disclosure, and which was not acquired, directly or indirectly, from the
disclosing Party;

 

  3.2.4  the receiving Party receives from third Parties, provided such
Confidential Information was not obtained by such third Parties, directly or
indirectly, from the disclosing Party on a confidential basis;

 

  3.2.5  results from research and development of the receiving Party
demonstrably independent of such disclosure;

 

  3.2.6  is required to be disclosed by legal process; provided, however, in
each case the Party so disclosing Confidential Information timely informs the
other Party and uses reasonable efforts to limit the disclosure and maintain
confidentiality to the extent possible and permits the other Party to attempt by
appropriate legal means to limit such disclosure;

 

  3.2.7  pertains to the tax structure or tax treatment of the transaction
embodied in this Master Agreement; or

 

  3.2.8  the disclosing Party identifies in writing as being for public
disclosure.

3.3 For purposes of this Master Agreement, the term “Confidential Information”
shall mean all of the data, information, technology, samples, DNA, specimens,
materials and any other information affecting the business operations of the

 

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disclosing Party received by the receiving Party from the disclosing Party, and
data results, and information developed by GTC and Merrimack hereunder.

3.4 In addition, neither Party shall originate any written publicity, news
release or other public announcement or statement relating to this Master
Agreement or to the performance hereunder or the existence of an arrangement
between the Parties without prior review and written approval of the other
Party, such approval not to be unreasonably withheld. Notwithstanding the
foregoing, either Party may make a public written disclosure if required by
applicable law provided that prior to making such written disclosure, the
disclosing Party shall provide the other Party with a copy of, and reasonable
opportunity to review, the materials to be disclosed. To the extent that the
non-disclosing Party requests that any information in the proposed disclosure be
deleted, the disclosing Party shall request confidential treatment of such
information pursuant to applicable law, so that there be omitted from the
materials that are publicly filed any information that the non-disclosing Party
requests to be deleted or redacted. Each Party shall be free at all times to
disclose the tax treatment and tax structure or the transaction embodied by this
Master Agreement.

4. Intellectual Property

4.1 Ownership.

 

  4.1.1  All Intellectual Property relating to the rhAFP molecule or its use
shall be solely owned by Merrimack, regardless of the designation of
inventorship between the Parties and their employees;

 

  4.1.2  All Intellectual Property relating to the Purification Technology shall
be solely owned by Merrimack, regardless of the designation of inventorship
between the Parties and their employees;

 

  4.1.3  All Intellectual Property relating to GTC’s Transgenic Technology and
the Clarification Technology shall be solely owned by GTC, regardless of the
designation of inventorship between the parties and their employees;

 

  4.1.4  All Transgenic Goats which are generated by GTC,, including the Founder
Goats, and all milk produced by such transgenic animals shall be solely owned by
Merrimack;

 

  4.1.5  All Cell Lines shall be solely owned by Merrimack; and

 

  4.1.6 

All Intellectual Property not described above in this Section 4 and invented
pursuant to this Master Agreement or any Ancillary Agreement that is within the
Field of Interest

 

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shall be jointly owned by the Parties, regardless of the designation of
inventorship between the parties and their employees (hereinafter, the “Joint
Intellectual Property”).

4.2 Maintenance of GTC Intellectual Property GTC shall have the primary right,
but not the obligation, to prepare, file, prosecute, and maintain any of the
Intellectual Property owned by it pursuant to Section 4.1 above (the “GTC
Intellectual Property”) at its sole cost and expense, and Merrimack shall
cooperate with GTC with respect thereto.

 

  4.2.1  If GTC desires to abandon any patent or patent application within the
GTC Intellectual Property in the Field of Interest with at least one Valid Claim
specifically related to the production of Transgenic rhAFP from Clarified Milk
in any country or to decline responsibility for the maintenance or prosecution
of any such patent or patent application in any country, GTC shall provide
Merrimack with sufficient prior written notice of such intended abandonment or
declination of responsibility such that Merrimack shall have the opportunity to
assume responsibility for such patent or patent application without the loss of
any rights therein, and Merrimack shall have the right, at its cost and expense,
to prepare, file, prosecute, and maintain the relevant patents and/or patent
applications in the relevant country or countries in the name of GTC to the
extent legally necessary. In such an event, GTC shall cooperate, and cause its
Affiliates to cooperate, with Merrimack with respect thereto. Should Merrimack
assume the responsibility for one or more patents or patent applications
included within the GTC Intellectual Property and thereafter proceed, maintain,
renew, revive or obtain any patent as a result of GTC’s abandonment or
declination of responsibility as contemplated herein, Merrimack shall thereafter
have a fully paid-up, perpetual and sub-licensable non-exclusive license to any
such patent or patent applications, including all related divisionals,
continuations, national stage applications or patents filed under the Patent
Cooperation Treaty of 1978, reissues, renewals, extensions or additions.
Furthermore, if Merrimack exercises such right, it shall no longer owe GTC
royalties with respect to such patents and/or patent applications. Specifically
excluded from this provision are any rights for Merrimack with regard to the
Transgenic Technology and the Clarification Technology.

 

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4.3 Maintenance of Merrimack Intellectual Property. Merrimack shall have the
primary right, but not the obligation, to prepare, file, prosecute, and maintain
the Intellectual Property owned by it pursuant to Section § 4.1 above (the
“Merrimack Intellectual Property”) Merrimack Intellectual Property at its sole
cost and expense and GTC shall cooperate, and cause its Affiliates to cooperate,
with Merrimack with respect thereto. If Merrimack desires to abandon any patent
or patent application covering the Purification Technology as it relates to
Biopharmaceuticals other than Transgenic rhAFP (a “Purification Technology
Patent”) in any country or to decline responsibility for the maintenance or
prosecution of any such patent application in any country, Merrimack shall
provide GTC with sufficient prior written notice of such intended abandonment or
declination of responsibility so that GTC shall have the opportunity to assume
responsibility for such patent or patent application without the loss of any
rights therein, and GTC shall have the right, at its cost and expense, to
prepare, file, prosecute, and maintain the relevant patents and patent
applications in the relevant country or countries in the name of Merrimack to
the extent legally necessary. In such an event, Merrimack shall cooperate, and
cause its Affiliates to cooperate, with GTC with respect thereto, at GTC’s cost
and expense. Should GTC assume the responsibility for one or more such patents
or Inventions and thereafter proceed, maintain, renew, revive or obtain any
patent as a result of Merrimack’s abandonment or declination of responsibility
as contemplated herein, GTC shall thereafter have a fully paid-up, perpetual and
sub-licensable non-exclusive license to any such patent or patent applications,
including all related divisionals, continuations, continuations-in-part,
national stage applications or patents filed under the Patent Cooperation Treaty
of 1978, reissues, renewals, extensions or additions. Furthermore, if GTC
exercises such right, it shall not owe Merrimack any royalties with respect to
such patents and/or patent applications.

4.4 Joint Intellectual Property. With regard to Joint Intellectual Property, GTC
shall have the right and authority to prepare, file, prosecute and maintain such
intellectual property and/or patent application at its sole expense. Such
authority shall also enable GTC to select the country or countries where
potential patent applications may be filed and to use patent counsel to further
this purpose that are reasonably satisfactory to both the Parties. The Parties
hereby agree that Byron Olsen, the Associate General Counsel of GTC
Biotherapeutics, is a satisfactory patent attorney for the management and
prosecution of any patent application or other Joint Intellectual Property
developed pursuant to this agreement.

4.5 License Grants

4.5.1 The Parties grant to each other, solely for the purpose of carrying out
their respective responsibilities under this Master Agreement and the Ancillary
Agreements, a non-exclusive, paid-up, royalty-free license to practice any
Invention pertaining to the Field of Interest including without limitation
Intellectual Property related to the production of Transgenic rhAFP from
Clarified Milk, assays and/or analytical techniques useful in the measurement or
characterization of Transgenic rhAFP in Clarified Milk or the purification of
Transgenic rhAFP from Clarified Milk developed pursuant to this Master Agreement
or any Ancillary Agreements, with a right

 

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to grant sublicenses. Notwithstanding any provision herein to the contrary the
breadth of such a license shall be only as it pertains to Transgenic rhAFP.
Moreover, and for the sake of clarity, this grant does not in any way include or
provide to Merrimack or any other third party, sublicense, assignee, contractor,
or consultant, any license, right-to-use, shop right or assignment with regard
to GTC’s Transgenic Technology at all, or separately to any of GTC’s proprietary
Clarification Technology not within the Field of Interest.

4.5.2 Merrimack hereby grants to GTC a perpetual, exclusive, paid-up,
royalty-free license to any rights it has in or to the Purification Technology
outside of the Field of Interest.

4.5.3 GTC hereby grants to Merrimack a perpetual, non-exclusive, paid-up,
royalty-free license to practice the Clarification Technology within the Field
of Interest.

4.6 Licensing. Each Party shall consult with the other, in good faith, regarding
commercialization or third party licensing of any Joint Intellectual Property
that may result from this Master Agreement.

4.7 Cooperation GTC will, upon request by Merrimack, cooperate in the drafting
of any and all patent applications, assignments and other instruments which
Merrimack deems are necessary or useful for the protection of any and all such
Merrimack Intellectual Property. With regard to GTC Intellectual Property, or
Joint Intellectual Property, which will be filed or prepared at GTC’s cost and
expense, Merrimack agrees to cooperate in the drafting of any and all patent
applications, assignments and other instruments which GTC deems are necessary or
useful for the protection of any and all such GTC Intellectual Property or Joint
Intellectual Property.

4.8 Notification of Patent Issuances. GTC and Merrimack shall notify each other
of the issuance of each patent included within the GTC Intellectual Property,
Joint Intellectual Property and the Merrimack Intellectual Property that have at
least one claim within the Field of Interest, giving the date of issue and the
patent number for each such patent. Such notice shall be given promptly, but in
any event within thirty (30) Business Days after receipt of such notice from an
appropriate oversight authority.

4.9 Patent Applications. The Parties will promptly furnish to each other a
written disclosure of any Intellectual Property within the Field of Interest,
the assays or analytical techniques developed and validated by Merrimack or GTC
for the purification or processing of Transgenic rhAFP under this Master
Agreement or Joint Intellectual Property conceived and/or reduced to practice
during the term of this Master Agreement. The Parties shall advise each other on
all communications concerning such Intellectual Property and will promptly
supply to the other Party full and complete copies of all papers received and
filed in connection with the prosecution and/or allowance thereof before the
United States Patent and Trademark Office or other equivalent foreign office.

 

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4.10 Reservation of Rights Except as expressly provided in this Section 4.10,
neither Party grants to the other whether implicitly, by estoppel, or otherwise,
any right or license in or to any of its intellectual property rights, Know-How
or Inventions. Each Party also represents and warrants that it has not entered
into any agreement with any other government entity or third Party, nor shall it
do so, which would give any such government entity or third Party any claim or
right to any inventions or discoveries arising under or in connection with this
Master Agreement.

4.11 Reports. GTC and Merrimack designated personnel will communicate at least
on a quarterly basis regarding the GTC Intellectual Property, Joint Intellectual
Property and the Merrimack Intellectual Property developed pursuant to this
Master Agreement. Each Party will provide a written report to the other Party
detailing the timing and payment status of necessary annuity payments,
maintenance fees, outstanding actions, appeals, new filings, oppositions,
interferences filed, to be filed with or under the jurisdiction of an
appropriate oversight authority (such as United States and Trademark Office with
regard to patent applications and other matters pending before it in the United
States of America) for which such Party is responsible hereunder. The first such
communication shall take place within thirty (30) days of the Effective Date of
this Master Agreement. The Parties shall keep complete and accurate records of
the status and progress of their respective Intellectual Property licensed to
the other Party hereunder. Each Party shall retain and will not destroy such
records without giving the other Parties prior written notice and the
opportunity to archive at least one copy of such records, which such records
shall be treated as Confidential Information.

5. Indemnification Merrimack and GTC shall each defend, indemnify and hold the
other and its affiliates the respective directors, officers, employees and
agents and affiliates, harmless from and against any and all losses, damages,
liabilities, claims, demands, judgments, settlements costs and expenses
(including, without limitation, reasonable attorneys’ fees and other costs of
defense) arising out of, relating to or resulting from the breach of any of
their respective representations, warranties and covenants contained within this
Master Agreement or their respective negligence or willful misconduct in the
conduct of their obligations or activities hereunder.

5.1 Notice of Indemnification A Party seeking indemnification pursuant to this
Section 5 ( an “Indemnified Party”) from or against the assertion of any claim
by a third person (a “Third Person Assertion”) shall give prompt notice to the
Party from whom indemnification is sought (the “Indemnifying Party”); provided,
however, that failure to give prompt notice shall not relieve the Indemnifying
Party of any liability hereunder (except to the extent the Indemnifying Party
has suffered actual material prejudice by such failure).

5.2 Assumption of Defense. Within thirty (30) business days of receipt of notice
from the Indemnified Party pursuant to Section 5.1 hereof, the Indemnifying
Party shall have the right exercisable by written notice to the Indemnified
Party, to assume the defense of a Third Person Assertion. If the Indemnifying
Party

 

15

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Confidential material omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote such omissions.

assumes such defense, the Indemnifying Party may select counsel, which shall be
reasonably acceptable to the Indemnified Party.

5.3 Failure to Defend. If the Indemnifying Party (i) does not assume the defense
of any Third Person Assertion; or (ii) having so assumed such defense,
unreasonably fails to defend against such Third Person Assertion, then, upon ten
(10) days’ written notice to the Indemnifying Party, the Indemnified Party may
assume the defense of such Third Person Assertion. In such event, the
Indemnified Party shall be entitled under this Section 5.3 as part of its
damages to indemnification for the costs of such defense.

5.4 Conflicts of Interest. If one of the Parties has been advised, by the
written opinion of counsel made available to both Parties, that the use of the
same counsel to represent both the Indemnified Party and the Indemnifying Party
would present a conflict of interest, then the Indemnified Party may select its
own counsel to represent it in the defense of the matter and the costs of such
defense shall be borne by the Indemnifying Party. The Indemnifying Party shall
be entitled to continue to handle its own representation in such matter through
its own counsel.

5.5 Settlement. The Party controlling the defense of a Third Person Assertion
shall have the right to consent to the entry of judgment with respect to, or
otherwise settle, such Third Person Assertion with the prior written consent of
the other Party, which consent shall not be unreasonably withheld.

5.6 Participation. The Indemnifying Party and the Indemnified Party shall
cooperate, in the defense or prosecution of any Third Person Assertion. The
Indemnified Party shall have the right to participate, at its own expense, in
the defense or settlement of any Third Person Assertion.

6. Term and Termination

 

  6.1 Term The initial term of this Master Agreement (the “Initial Term”) shall
commence on the Effective Date and, unless extended by the Parties, shall
terminate on the ************ anniversary of the Effective Date.

 

  6.2 Early Termination

This Master Agreement may be terminated at any time upon mutual agreement of the
Parties. In addition:

 

  6.2.1 Either Party may terminate this Master Agreement as set forth in
Section 7 or 8 below;

 

  6.2.2 Either Party may terminate this Master Agreement upon sixty (60) days
written notice in the event the other Party fails to make any payments due
pursuant to this Master Agreement, unless such failure is remedied within such
sixty (60) Business Day notice period;

 

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  6.2.3  Either Party may terminate this Master Agreement upon sixty (60) days
written notice in the event the other Party is in material breach of any other
obligation hereunder and such other Party or its Affiliate shall fail to remedy
any such breach within sixty (60) days after written notice of such breach;

 

  6.2.4  Either Party may terminate this Master Agreement immediately upon
written notice to the other Party, in the event that the other Party has ceased
conducting business in the ordinary course (it being agreed that for this
purpose the conduct of research and development activities shall be deemed to
constitute the conduct of business); or

 

  6.2.5  Either Party may terminate this Master Agreement immediately upon
written notice if one or more of the following circumstances remains uncorrected
for more than ninety (90) days: (a) entry of an order for relief by or against
the other Party under Title 11 of the United States Code or any foreign
bankruptcy code; (b) the making by the other Party of a general assignment to
the benefit of creditors; (c) the appointment of a general receiver or trustee
in bankruptcy of the other Party’s business or property; or (d) action by the
other Party under any insolvency or similar law for the purpose of its
bankruptcy, reorganization, or liquidation.

 

  6.2.6  Merrimack may terminate this Master Agreement and any Ancillary
Agreements upon six (6) months written notice to GTC in the event General
Electric Capital Corporation, or any other holder of a mortgage or other
encumbrance on the Property, initiates proceedings to foreclose on all or a
portion of the Property.

 

  6.3 Effect of Termination or Expiration

 

  6.3.1 

In General. Upon termination or expiration of this Master Agreement, neither
Party will have any further obligations under this Master Agreement, except
(i) the liabilities accrued through the date of termination, including
compensation for costs incurred through the date of termination; (ii) payment of
actual or committed costs incurred to date towards any milestones in process as
of the time of termination or expiration; and (iii) the obligations which
expressly survive this Master Agreement as set forth in Section 6.3.2 hereof.
Upon termination, GTC will, if requested to do so by Merrimack, dispose of any
Transgenic rhAFP and/or any Transgenic Goats generated

 

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by GTC pursuant to the Project in accordance with Merrimack’s instructions and
at Merrimack’s expense.

 

  6.3.2  License Rights. Subject to Sections 7 and 8 below, upon a termination
of this Master Agreement by GTC under Section 6.2.1, 6.2.2, 6.2.3, 6.2.4 or
6.2.5 above, the license rights granted to Merrimack under Section 4.5 above
shall terminate and the license rights granted to GTC shall survive. Upon a
termination of this Master Agreement by Merrimack under Section 6.2 above, the
license rights granted to GTC under Section 4.5 above shall terminate and the
license rights granted to Merrimack shall survive.

 

  6.3.2.1  Notwithstanding the foregoing, Merrimack may cause the license rights
granted to it by GTC under this Master Agreement to survive any termination of
this Master Agreement in which they would otherwise terminate as a result of
provisions of Section 6.3.2 by agreeing to pay, in addition to the then current
royalty requirements under Section 2 of this Master Agreement, an additional
royalty equal to 2% of Net Partner Sales, on the terms set forth in Section 2.

 

  6.4 Possession of Merrimack Animals

 

  6.4.1 For the avoidance of doubt, at any time (whether before or after
termination of this Agreement) and for any reason, in the sole discretion of
Merrimack, Merrimack may take possession of any and all animals owned by
Merrimack, and GTC shall cooperate with Merrimack in connection therewith.
Taking of possession shall be at Merrimack’s expense and may, but is not
required to, involve the relocation of the Merrimack animals to certain premises
leased by Merrimack from GTC. Such taking of possession shall not reduce or
eliminate any of Merrimack’s obligations under this Agreement or any of the
Ancillary Agreements.

 

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Confidential material omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote such omissions.

7 Special Protections.

 

  7.1 Change in Control at GTC. If, after a Change in Control, GTC’s successor
in interest commits a willful breach of this Master Agreement, then upon written
notice from Merrimack, Merrimack shall be entitled to each of the following
remedies at its sole option, which remedies are not intended to be exclusive of
any other remedies available to Merrimack at law or equity upon a willful breach
of this Master Agreement:

 

  7.1.1  At Merrimack’s option, the Master Agreement with GTC’s successor in
interest may be cancelled by written notice;

 

  7.1.2  Merrimack shall have a fully-paid, perpetual, assignable license to use
the GTC Intellectual Property within the Field of Interest for the sole purpose
of producing clinical grade Transgenic rhAFP Product from a Clarified Milk
product, with right to sublicense;

 

  7.1.3  GTC’s successor in interest shall reimburse Merrimack for all amounts
paid by Merrimack to GTC or its successor pursuant to this Master Agreement, up
to a maximum dollar value of ************;

 

  7.1.4  Upon notice from Merrimack, GTC’s successor in interest shall transport
all Transgenic Goats at its expense to any facility designated by Merrimack that
is located in the United States and within 750 miles of GTC’s Charlton
Massachusetts facility; and

 

  7.1.5  GTC’s successor shall be obligated to (i) provide Merrimack the
Know-How and technical support necessary to permit Merrimack to continue
production of Transgenic rhAFP from a Clarified Milk product for up to one year
after a Change in Control and to (ii) take all reasonably necessary steps in
order allow access to Merrimack, under the reasonable control of GTC and/or its
successor in interest, to the physical facilities used in the breeding and
maintenance of the Transgenic Goats produced under this Master Agreement or the
Ancillary Agreements including to the barn housing the rhAFP Transgenic Goats if
needed.

 

  7.1.6  The above provisions apply only to a successor in interest to GTC.

 

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8. Protections for Rights in Bankruptcy and Other Failures.

 

  8.1 Notice. Each Party shall notify the other in writing promptly after:
(i) the filing by or against such Party of any petition in bankruptcy or similar
filing seeking relief from creditors; (ii) receipt by such Party of any notice
of foreclosure and/or default that could be reasonably foreseen to have the
effect of preventing the other Party from practicing the licenses granted to it
hereunder. GTC shall notify Merrimack of any default by GTC, or receipt by GTC
of notice of default or letter threatening default, under that certain Mortgage,
Security Agreement and Fixture Filing by GTC in favor of General Electric
Capital Corporation, dated May 26, 2004, or under any other mortgage or
agreement encumbering all or a portion of the Property.

 

  8.2 Representation and Warranty. Each Party hereby represents, warrants, and
covenants that of the Effective Date it has no knowledge of any bankruptcy,
insolvency, reorganization, or liquidation, notices of foreclosure and/or
default, or other filing or proceedings with respect to it that would affect its
promises hereunder or preclude the other Party from practicing the licenses
granted to it hereunder throughout the term of this Master Agreement.

 

  8.3 Failure by GTC. If GTC (i) initiates or becomes subject to one or more of
the following circumstances: (A) seek the entry of an order for relief from or
against GTC or any other party under Title 11 of the United States Code or any
foreign bankruptcy code; (B) making a general assignment to the benefit of its
creditors; (C) make or be required to accept the appointment of a general
receiver or trustee in bankruptcy of its business or property or (ii) otherwise
becomes unable to perform its obligations under the Master Agreement or any of
the Ancillary Agreements (collectively, a “Failure by GTC”, then:

 

  8.3.1  At Merrimack’s option, the Master Agreement and any Ancillary Agreement
with GTC may be cancelled by written notice;

 

  8.3.2  Merrimack shall have a royalty bearing, perpetual, assignable license
to use the GTC Intellectual Property within the Field of Interest for the sole
purpose of producing Transgenic rhAFP Product from a Clarified Milk product,
with right to sublicense. Such royalty shall be equal to the royalty in effect
at the time the license is assigned;

 

  8.3.3 

At Merrimack’s request, GTC shall transport all Transgenic Goats that are in
GTC’s possession at Merrimack’s expense to any facility designated by Merrimack
that is located in the

 

20

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Confidential material omitted and filed separately with the Securities and
Exchange Commission. Asterisks denote such omissions.

 

  United States and within 750 miles of GTC’s ************ Massachusetts
facility; and

 

  8.3.4  GTC shall be obligated, at Merrimack’s expense, to (i) provide
Merrimack the Know-How and technical support necessary to permit Merrimack to
continue production of Transgenic rhAFP from a Clarified Milk product for up to
one year after a Change in Control and to (ii) take all reasonably necessary
steps in order allow access to Merrimack, under the reasonable control of GTC
and/or its successor in interest, to the physical facilities used in the
breeding and maintenance of the Transgenic Goats produced under this Master
Agreement including to the barn housing the rhAFP Transgenic Goats if needed.

 

  8.3.5  Upon the notification set forth in Section 8.1, Merrimack shall be
entitled to contact all GTC employees, contractors and suppliers who are
directly involved in the handling and care of the Transgenic Goats or in the
manufacture of the Clarified Milk and to solicit them for employment with
Merrimack or to enter into a contract with Merrimack.

 

  8.4 Legal Compliance. The Parties intend that the license and protections
granted pursuant to this Section 8 shall be effective and fully compliant with
11 USC §365(n) and 11 USC § 362 of the United States Bankruptcy code such that
the Parties can exercise and otherwise utilize the rights granted hereunder.

9. Assignability. This Master Agreement and the Ancillary Agreements, and the
rights and obligations hereunder and thereunder, may not be assigned or
transferred by either Party without the prior written consent of the other
Party, such consent not to be unreasonably withheld. Notwithstanding the
foregoing, either Party may assign this Master Agreement and the Ancillary
Agreements, without the other’s consent, to an Affiliate or in connection with
(i) the merger or consolidation of such Party with or into another person firm
or entity; or (ii) the sale by such Party of all or substantially all of the
business that is the subject matter of this Master Agreement; provided that in
any such case the assignee agrees in writing to be bound by the provisions of
this Master Agreement. This Master Agreement shall be binding on the successors
and assigns of the Parties hereto. Violation of this provision shall be
considered a material breach.

10. Publication. Any publication or presentation relating to the Project must
first be approved in writing by both Parties, such approval not to be
unreasonably withheld. Each Party agrees to submit, for review, any proposed
publication (including any writing to be presented orally) relating to the
Project at least forty-five (45) days prior to submission for publication or
presentation. Either Party may request a delay in publication or presentation if
any of the information to be published or presented is

 

21

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reasonably deemed by the requesting Party to represent patentable information.
If such a delay is requested, the other Party agrees to delay the publication or
presentation, for a period of ninety (90) days from the date of such request.
Such period may be extended, if necessary, for an additional period mutually
acceptable to the Parties. Notwithstanding the foregoing, both Parties agree
that: (i) no publication or presentation shall contain Confidential Information
with respect to which it has confidentiality obligations and (ii) GTC’s approval
of a publication by Merrimack shall be required only if and to the extent a
proposed publication relates to Transgenic Technology or Clarification
Technology.

11. Governing Law and Entirety. The validity, interpretation and performance of
this Master Agreement shall be governed and construed in accordance with the
laws of the Commonwealth of Massachusetts, U.S.A. Except with respect to those
provisions which survive the June 27, 2003 Agreement between GTC and Merrimack
pursuant to Section 24 of that agreement, this Master Agreement and the
Ancillary Agreements, along with any separate confidentiality agreements between
the Parties, constitutes the full understanding of the Parties with respect to
the subject matter hereof, and a complete and exclusive statement of the terms
of their agreement, and no terms, conditions understanding or agreement
purporting to modify or vary the terms of this Master Agreement shall be binding
unless made in writing and signed by the Party to be bound. In the event of any
inconsistency between the provisions of any Ancillary Agreement and this Master
Agreement, the terms of this Master Agreement shall control the relationship
between the Parties.

12. Dispute Resolution. The Parties hereto hereby agree to perform the terms of
this Master Agreement in good faith, and to attempt to resolve any controversy,
claim or dispute arising hereunder in good faith. Any dispute regarding the
validity, construction, interpretation or performance of this Master Agreement
(other than any provisions, hereof relating to any intellectual property rights,
or the confidentiality obligations contained in Section § 3 hereof) shall be
submitted to binding arbitration in Boston, Massachusetts, to be conducted in
accordance with the Arbitration Rules of the American Arbitration Association
(“AAA”). In connection with the foregoing, the Parties hereto hereby submit to
the jurisdiction of the Federal and state courts of the Commonwealth of
Massachusetts. Any arbitration hereunder shall be submitted to an arbitration
tribunal made up of three (3) members, one of whom shall be selected by
Merrimack, one of whom shall be selected by GTC, and one of whom shall be
selected by the other two arbitrators. The order or award of the arbitrators
shall be final and may be enforced in any court of competent jurisdiction in the
United States. The prevailing Party in any legal or arbitration action brought
by one Party against the other shall be entitled, in addition to any other
rights and remedies it may have, to reimbursement for its expenses incurred
thereby, including court costs and reasonable attorneys’ fees. The Parties shall
have the right of limited pre-hearing discovery, including (i) exchange of
witness lists, (ii) exchange of documentary evidence and reasonably related
documents, (iii) written interrogatories, and (iv) subject to the reasonable
discretion of the arbitrators and upon good cause shown depositions under oath
of any witnesses who are to be called to testify at the arbitration hearing. As
soon as the discovery is concluded, the arbitrators

 

22

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shall hold a hearing in accordance with the aforesaid shall hold a hearing in
accordance with the aforesaid AAA rules.

13. No Waiver. No waiver of any term or condition of this Master Agreement shall
be valid or binding on either Party unless agreed in writing by the Party to be
charged. The failure of each Party to enforce at any time any of the provisions
of this Master Agreement, or the failure to require at any time performance by
the other Party of any of the provisions of this Master Agreement, shall in no
way be construed to be a present or future waiver of such provisions, nor in any
way affect the validity of either Party to enforce each and every such provision
thereafter.

14. Counterparts. This Master Agreement may be executed in two counterparts,
each of which shall be deemed an original and both of which together shall
constitute one instrument.

15. Independent Contractors. The relationship of Merrimack and GTC established
by this Master Agreement is that of independent contractors, and nothing
contained in this Master Agreement shall be construed to: (i) give either Party
the power to direct or control the day-to-day activities of the other;
(ii) constitute the Parties as partners, joint venturers, co-owners or otherwise
as participants in a joint or common undertaking; or (iii) allow a Party to
create or assume any obligation on behalf of the other Party for any purpose
whatsoever. Nothing in this Master Agreement will give rise to the creation of
any labor relation by and between either Party or any employees of the other
Party.

16. The Initial Agreements. As evidenced by their execution hereof, the Parties
hereto expressly acknowledge that each of the Initial Agreements, other than the
portions of those agreements which were intended to survive termination have
been superceded and replaced as a result of the mutual agreement of the Parties
hereto, and that neither Party will have any further obligations thereunder
except as expressly set forth in this Master Agreement.

17. Notices. Any notice required or permitted to be given under this Master
Agreement shall be in writing and shall be deemed to have been sufficiently
given for all purposes hereof, if mailed by first class, certified or registered
mail, postage prepaid, addressed to the Party to be notified and its address or
such other addresses have been furnished in writing to the notifying Party.
Unless otherwise specified in writing, the mailing address shall be as follows:

 

To Merrimack:

  

Merrimack Pharmaceuticals, Inc.

  

101 Binney Street

  

Cambridge, Massachusetts 02142

  

Attention: Robert Mulroy, President & CEO

  

Fax: (617) 354-8391

 

23

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with a copy to

  

Lawrence S. Wittenberg, Esq.

  

Goodwin Procter, LLP

  

53 State Street

  

Boston, MA 02109

 

To GTC:

  

GTC Biotherapeutics Inc

  

175 Crossing Boulevard

  

Framingham, MA 01701

  

USA

  

Attention: Chairman, President & CEO

  

Facsimile: (508) 370-3797

 

with a copy to:

  

GTC Biotherapeutics Inc

  

175 Crossing Boulevard

  

Framingham, MA 01701

  

USA

  

Attention: Sr. Vice President & General Counsel

  

Facsimile: (508) 370-3797

18. No Other Rights. Except as expressly set forth in this Section, no other
rights, express or implied, are granted hereunder to either Party under any
Patent Rights, GTC’s Transgenic Technology or Know How of the other Party.
Except as otherwise expressly provided in this Section, under no circumstances
shall either Party, as a result of this Master Agreement, obtain any ownership
interest in or other right to the Patent Rights or Know How of the other Party,
including intellectual property owned, controlled or developed by or licensed to
the other Party prior to or any time during the term of this Master Agreement.

19. Insurance. Each Party shall maintain insurance, including product liability
insurance and workers compensation or an insurance product with a similar
purpose, with respect to its activities hereunder. Such insurance shall be in
such amounts and subject to such deductibles as the Parties may agree based upon
standards prevailing in the industry at the time. Each Party may satisfy its
obligations under this Section § 27 through self-insurance to the same extent.

20. Severability. If any provision or condition of this Master Agreement is
determined to be invalid, illegal or unenforceable, the remaining provisions and
conditions of this Master Agreement shall remain in full force and effect and
the Parties hereby acknowledge and agree that they would have executed the
remaining portion hereof without including the portion so declared invalid, void
or unenforceable. In the event of any such determination, the Parties agree to
negotiate in good faith to modify this Master Agreement to fulfill as closely as
possible the original intent and purpose hereof. To the extent permitted by law,
the Parties hereby, to the same extent, waive any provision of law that renders
any provision hereof prohibited or unenforceable in any respect.

21. Force Majeure. If the performance of this Master Agreement or any obligation
hereunder is prevented, restricted or interfered with by reason of fire or other

 

24

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casualty or accident, strikes or labor disputes, inability to procure raw
materials, power or supplies, terrorist act or other violence, any law, order,
proclamation, regulation, ordinance, demand or requirement of any government
agency, or any other act or condition whatsoever beyond the control of a Party
hereto, the Party so affected, upon giving prompt notice to the other Party,
shall be excused from such performance to the extent of such prevention,
restriction or interference; provided, however, that the Party so affected shall
use reasonable efforts to avoid or remove such causes of non-performance and
shall continue performance hereunder with the utmost dispatch whenever such
causes are removed.

22. Diligence. Under the terms of this Master Agreement GTC and Merrimack each
agree to use commercially reasonable efforts to achieve the terms of this Master
Agreement. Both Parties agree to be flexible and to work together in good faith
to optimally coordinate the desired outcomes for this Project.

 

GTC Biotherapeutics, Inc.

   Merrimack Pharmaceuticals, Inc. 175 Crossing Boulevard, Suite 410    101
Binney Street Framingham, MA 01702    Cambridge, MA 02142 Attn: Chairman,
President & CEO    Attn: President & CEO

[Remainder of Page Intentionally Left Blank]

 

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IN WITNESS WHEREOF, duly-authorized representatives of the Parties have signed
this Master Agreement as a document under seal as of the Effective Date.

 

GTC BIOTHERAPEUTICS, INC.     MERRIMACK PHARMACEUTICALS, INC.

By:

        

By:

    

Print Name:

        

Print Name:

    

Title:

        

Title:

    

Date:

        

Date:

    

 

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