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Exhibit 10.3    
    


Confidential
Materials omitted and filed separately with the

Securities and Exchange Commission. Asterisks denote omissions. 


 
 

FOURTH AMENDMENT TO THE NOVEMBER 1, 2002 LICENSE


        This
Fourth Amendment, effective as of the date set forth above the signatures of the parties below, pertains to the Amended and Restated Exclusive Patent License Agreement, effective on
November 1, 2002, as subsequently amended by a First Amendment on November 15, 2002, a Letter Agreement on September 12, 2003, a Letter Agreement on October 22, 2003, a
Second Amendment on November 19, 2003 and a Third Amendment on April 2,2004, by and between the Massachusetts Institute of Technology
("M.I.T.") and Momenta Pharmaceuticals, Inc. ("COMPANY"). 


        WHEREAS,
M.I.T. is the owner of certain new intellectual property closely related to the PATENT RIGHTS of the Amended and Restated Exclusive Patent License Agreement and desires to have
this technology developed and commercialized to benefit the public; and 


        WHEREAS,
COMPANY desires to add this new technology to the PATENT RIGHTS and M.I.T. is willing to grant a license thereunder. 


        NOW,
THEREFORE, M.I.T. and COMPANY hereby agree to modify the Amended and Restated Exclusive Patent License Agreement as follows: 



	1.
	The
patent rights of the following M.I.T. Case Nos. shall be added to the PATENT RIGHTS ENZYMES and the PATENT RIGHTS, as defined by their inclusion in the attached APPENDIX H: 





M.I.T. Case No. [**]

Entitled: [**]

By [**]



M.I.T. Case No. [**]

Entitled: [**]

By [**]



M.I.T. Case No. [**]

Entitled: [**]

By [**]






	2.
	In
consideration of the addition of the patent rights of M.I.T. Case Nos. [**], and [**] to the PATENT RIGHTS ENZYMES and the license
granted in the FIELD ENZYMES hereunder:



	a.
	COMPANY
shall pay M.I.T. a Patent Addition Fee of [**] dollars ($[**]) for each M.I.T. Case added for a total of
[**] dollars ($[**]), which shall be due within thirty (30) days of the Effective Date of this Fourth Amendment; and



	b.
	COMPANY
shall be responsible for payment of all fees and costs relating to the filing, prosecution and maintenance of the patent rights of M.I.T. Case Nos. [**]
and [**], whether such fees and costs were incurred [**] the Effective Date of this Fourth Amendment; provided, however, that should M.I.T. license the
PATENT RIGHTS ENZYMES to one or more third parties, M.I.T. shall promptly notify COMPANY in writing and any fees and costs associated with PATENT RIGHTS ENZYMES shall be allocated in a fair and
equitable manner between COMPANY and any subsequent licensees of the PATENT RIGHTS ENZYMES on a go-forward basis. 






All
other terms and conditions of the License Agreement shall remain unchanged. 










The EFFECTIVE DATE of this Amendment is July 17, 2004.


Agreed
to for: 



	MASSACHUSETTS INSTITUTE OF

TECHNOLOGY	MOMENTA PHARMACEUTICALS, INC.
	By	/s/ Lita L. Nelsen	By	/s/ Susan K. Whoriskey
	Name	Lita L. Nelsen	Name	Susan K. Whoriskey
	Title	Technology Licensing Officer	Title	Vice President, Licensing & Business Development
	Date	July 26, 04	Date	July 28, 2004









 
 

APPENDIX H
  PATENT RIGHTS ENZYMES



M.I.T. Case No. [**]

Entitled: [**]

By [**]




Patent
Convention Treaty Serial No. [**]

United States of America Serial No. [**]

Entitled: [**]





M.I.T. Case No. [**]

Entitled: [**]

By [**]




Patent
Convention Treaty Serial No. [**]

United States of America Serial No. [**]

Entitled: [**]





M.I.T. Case No. [**]

Entitled: [**] 

By [**]




Japan
Serial No. [**] 

Patent Convention Treaty Serial No. [**]

United States of America Serial No. [**]

Entitled: [**]





M.I.T. Case No. [**]

Entitled: [**]

By [**]

[**]



M.I.T. Case No. [**]

Entitled: [**]

By [**]




United
States of America Serial No. [**]

United States of America Serial No. [**]

Entitled: [**]





M.I.T. Case No. [**]

Entitled: [**]

By [**]




[**]  

















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Exhibit 10.3


FOURTH AMENDMENT TO THE NOVEMBER 1, 2002 LICENSE

APPENDIX H PATENT RIGHTS ENZYMES