INVESTOR RIGHTS AGREEMENT

Exhibit 10.2

Execution Copy

Novartis Pharma AG

AND

Momenta Pharmaceuticals, Inc.

INVESTOR RIGHTS AGREEMENT

TABLE OF CONTENTS

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INVESTOR RIGHTS AGREEMENT

THIS INVESTOR RIGHTS AGREEMENT (this " Agreement ") is made as of July 25, 2006, by and between Novartis Pharma AG (the " Investor "), a corporation organized under the laws of Switzerland, with its principal place of business at Lichtstraße 35, CH 4058 Basel BS, and Momenta Pharmaceuticals, Inc. (the " Company "), a Delaware corporation with its principal place of business at 675 West Kendall Street, Cambridge, Massachusetts 02142.

WHEREAS, the Company proposes to issue and sell to the Investor shares of its Common Stock, par value $0.0001 per share (the " Common Stock "), pursuant to the Stock Purchase Agreement dated as of July 25, 2006 (the " Purchase Agreement "); and

WHEREAS, as a condition to consummating the transactions contemplated by the Purchase Agreement, the Investor and the Company have agreed upon registration rights and certain other rights and restrictions as set forth herein.

NOW, THEREFORE, in consideration of the premises and mutual agreements hereinafter set forth, and for other valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1.              Definitions.   As used in this Agreement, the following terms shall have the following meanings:

(a)  The term " Affiliate " means, with respect to any Person, any other Person that directly or indirectly, controls, is controlled by or is under common control with such Person.  For the purposes of this definition, "control" (including with correlative meanings, the terms "controlled by" and "under common control with") shall mean the possession, directly or indirectly, of the power to direct or cause the direction of the management and policies of such Person, whether through the ownership of voting securities or by contract or otherwise.

(b)  The term " Agreement " shall have the meaning set forth in the Preamble to this Agreement.

(c)  The term " Collaboration and License Agreement " means that certain Collaboration and License Agreement to be entered into between the Company and the Investor contemplated by the memorandum of understanding among the Company and the Investor (or an affiliate of the Investor) dated the date hereof.

(d)  The term " Common Stock " shall have the meaning set forth in the recitals to this Agreement.

(e)  The term " Demand Registration Request " has the meaning set forth in Section 7.

(f)  The term " Effectiveness Period " has the meaning set forth in Section 3(a).

(g)  The term " Exchange Act " means the Securities Exchange Act of 1934, as amended.

(h)  The term " Existing Registration Rights Agreement " means the Second Amended and Restated Investors’ Rights Agreement, dated as of February 27, 2004, by and among the Purchasers listed therein, the Founders listed therein and the Company, as amended by Amendment No. 1 to such Agreement dated June 10, 2004.

(i)  The term " Holder " means the Investor for so long as it owns Registrable Shares and any Person to whom the Investor transfers Registrable Shares in accordance with the terms and conditions of this Agreement.  If Registrable Shares are held by a nominee for the beneficial owner thereof, the beneficial owner thereof may, at its option, be treated as the Holder of such Registrable Shares for purposes of any request or other action by any Holder or Holders of Registrable Shares pursuant to this Agreement (or any determination of any number or percentage of shares constituting Registrable Shares held by any Holder or Holders of Registrable Shares contemplated by this Agreement), provided that the Company shall have received assurances reasonably satisfactory to it of such beneficial ownership.

(j)  The term " Notices " has the meaning set forth in Section 21.

(k)  The term " Investor " shall have the meaning set forth in the Preamble to this Agreement.

(l)  The term " Person " means any individual, corporation, association, partnership, joint venture, entity, trust, estate, limited liability company, limited partnership, joint stock company, unincorporated organization or government or any agency or political subdivision.

(m)  The term " Purchase Agreement " shall have the meaning set forth in the recitals to this Agreement.

(n)  The terms " register ," " registered ," and " registration " refer to a registration effected by preparing and filing a registration statement in compliance with the Securities Act and the declaration or ordering of effectiveness of such registration statement.

(o)  The term " Registrable Shares " means (i) the Common Stock purchased by the Investor pursuant to the Purchase Agreement and (ii) any Common Stock of the Company issued as a dividend or other distribution with respect to, or in exchange or in replacement of, such Common Stock after the date hereof; provided , however , that shares of Common Stock which are Registrable Shares shall cease to be Registrable Shares (A) upon any sale pursuant to a registration statement under the Securities Act or (B) upon any sale or transfer in any manner to a Person or entity which is not entitled, pursuant to Section 11, to the rights under this Agreement.

(p)  The term " Rule 144 " means Rule 144 promulgated under the Securities Act.

(q)  The term " SEC " means the Securities and Exchange Commission.

(r)  The term " Securities Act " means the Securities Act of 1933, as amended.

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(s)  The term " Similarly Situated Person " means any third party that (i) has entered into a collaboration agreement with the Company or one of its subsidiaries that is required to be filed by the Company in accordance with Item 601 of Regulation S-K of the Securities Act and (ii) in connection with such collaboration, acquires equity securities of the Company equal to ten percent (10%) or more of the then outstanding equity securities of the Company.

(t)  The term " Subsequent Registration " has the meaning set forth in Section 7(c).

(u)  The term " Termination Date " means the earliest of (a) the date on which the Company (i) enters into a definitive agreement with an unaffiliated third party or parties to merge, consolidate or otherwise combine, with such third party or parties in a transaction where the holders of the Company’s outstanding shares immediately prior to such merger or consolidation would hold, in the aggregate, securities possessing less than fifty percent (50%) of the total combined voting power of the combined or surviving entity immediately after such merger or consolidation, or to sell all or substantially all of the Company’s business or assets or securities representing a majority of the then outstanding voting power of the Company’s securities, (ii) makes a public announcement that it is negotiating a transaction with an unaffiliated third party or parties covered by the foregoing clause (a)(i), or (iii) consummates a transaction with an unaffiliated third party or parties covered by the foregoing clause (a)(i); or (b) the date a third party or group (as defined above) (i) acquires beneficial ownership of voting securities (including those convertible or exchangeable into such voting securities) of the Company representing twenty percent (20%) or more of the then outstanding voting securities of the Company; or (ii) announces or commences a tender or exchange offer to acquire voting securities of the Company which, if successful, would result in such Person or group owning, when combined with any other voting securities of the Company owned by such Person or group, twenty percent (20%) or more of the then outstanding voting securities of the Company.

(v)  The term " Valid Business Reason " has the meaning set forth in Section 7.

2.              Company Registration.   If (but without any obligation to do so) the Company proposes to register any of its stock or other securities under the Securities Act in connection with the public offering of such securities solely for cash, other than (a) a registration relating solely to the sale of securities to participants in a stock plan, or (b) a registration on Form S-4 (or any successor form) relating solely to a transaction pursuant to the SEC’s Rule 145, the Company shall, at such time, promptly give each Holder written notice of such registration.  Upon the written request of each Holder given within fifteen (15) days after receipt by such Holder of such notice by the Company in accordance with Section 21, the Company shall, subject to the provisions of Section 5, cause to be registered under the Securities Act all of the Registrable Shares that each such Holder has requested to be registered; provided, that the Company shall have the right to postpone or withdraw any registration statement relating to an offering in which the Holders are eligible to participate under this Section 2 without any liability or obligation to the Holders under this Section 2.  Any Holder shall have the right to withdraw its request for inclusion of its Registrable Shares in any registration statement pursuant to this Section 2 by giving written notice to the Company of its request to withdraw; provided, however, that (i) such request must be made in writing prior to the earlier of the execution of the underwriting agreement or the execution of the custody agreement with respect to such registration and (ii) such withdrawal shall be irrevocable and, after making such withdrawal, a

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Holder shall no longer have any right to include Registrable Shares in the registration as to which such withdrawal was made.

3.              Obligations of the Company.   Whenever required under Section 2 or Section 7 to use its reasonable best efforts to effect the registration of any Registrable Shares, the Company shall, as expeditiously as reasonably possible:

(a)  Prepare and file with the SEC a registration statement with respect to such Registrable Shares and use its reasonable best efforts to cause such registration statement to become and remain effective for twelve (12) months from the effective date or such lesser period until the distribution thereof has been completed (the " Effectiveness Period ").

(b)  Prepare and file with the SEC such amendments and supplements to such registration statement and the prospectus used in connection with such registration statement as may be necessary to comply with the provisions of the Securities Act with respect to the disposition of all securities covered by such registration statement.

(c)  Furnish, without charge, to the selling Holders at least one photocopy of a signed copy, of the registration statement and any post-effective amendments thereto, including financial statements and schedules, all documents incorporated therein by reference, all exhibits (including those incorporated by reference) and any free writing prospectus utilized in connection therewith and such reasonable numbers of copies of the registration statement, each amendment and supplement thereto, each prospectus, related there to including a preliminary prospectus, related thereto in conformity with the requirements of the Securities Act, each free writing prospectus utilized in connection therewith, and such other documents as they may reasonably request in order to facilitate the disposition of such Registrable Shares owned by them.

(d)  Use its reasonable best efforts to register and qualify the Registrable Shares covered by such registration statement under such other securities or "blue sky" laws of such states as shall be reasonably appropriate for the distribution of the securities covered by the registration statement and do any and all other acts and things which may be reasonably necessary or advisable to enable the selling Holders or underwriter, if any, to consummate the disposition of the Registrable Shares in such jurisdictions, provided that the Company shall not be required in connection therewith or as a condition thereto to qualify to do business, to amend its certificate of incorporation or by-laws in a manner that the Board of Directors of the Company determines is inadvisable or to file a general consent to service of process in any such states or jurisdictions, and further provided that (anything in this Agreement to the contrary notwithstanding with respect to the bearing of expenses) if any jurisdiction in which the securities shall be qualified shall require that expenses incurred in connection with the qualification of the securities in that jurisdiction be borne by selling stockholders, then such expenses shall be payable by selling stockholders on a pro rata basis, to the extent required by such jurisdiction.

(e)  Provide a transfer agent and registrar for the Common Stock no later than the effective date of the first registration of any Registrable Shares.

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(f)  Otherwise use its reasonable best efforts to comply with all applicable rules and regulations of the SEC.

(g)  Use its reasonable best efforts to cause all such Registrable Shares to be listed on a national securities exchange (if such securities are not already so listed) and on each additional national securities exchange on which similar securities issued by the Company are then listed, if the listing of such securities is then permitted under the rules of such exchange.

(h)  Enter into such customary agreements (including an underwriting agreement in customary form) and take such other actions as the selling Holders of Registrable Shares shall reasonably request in order to expedite or facilitate the disposition of such Registrable Shares.

(i)  (x) Make generally available to its security holders, as soon as reasonably practicable after the effective date of the registration statement (and in any event within 90 days after the end of such twelve month period described hereafter), an earnings statement (which need not be audited) covering the period of at least twelve consecutive months beginning with the first day of the Company’s first calendar quarter after the effective date of the registration statement, which earnings statement shall satisfy the provisions of Section 11(a) of the Securities Act and Rule 158 thereunder and (y) make available for inspection by any selling Holder of Registrable Shares, by any managing underwriter participating in any disposition to be effected pursuant to such registration statement and by any attorney, accountant or other agent retained by any such selling Holder or any such underwriter, all pertinent financial and other records and pertinent corporate documents and properties of the Company, and cause all of the Company’s officers, directors and employees to supply all information reasonably requested by any such selling Holder, underwriter, attorney, accountant or agent in connection with such registration statement.

(j)  Use reasonable best efforts to prevent the issuance of any stop order suspending the effectiveness of such registration statement or of any order preventing or suspending the use of any preliminary prospectus and, if any such order is issued, to obtain the lifting thereof at the earliest reasonable time.

(k)  In the case of an underwritten offering, use its reasonable best efforts to obtain an opinion from the Company’s counsel and a "cold comfort" letter from the Company’s independent public accountants in customary form and covering such matters as are customarily covered by such opinions and "cold comfort" letters delivered to underwriters in underwritten public offerings, which opinion and letter shall be reasonably satisfactory to the underwriter, if any, and furnish to each Holder participating in the offering to the extent possible and to each underwriter, if any, a copy of such opinion and letter addressed to such Holder or underwriter;

(l)  Deliver promptly to each Holder participating in the offering and each underwriter, if any, copies of all correspondence between the SEC and the Company, its counsel or auditors and all memoranda relating to discussions with the SEC or its staff with respect to the registration statement, other than those portions of any such memoranda which contain information subject to attorney-client privilege with respect to the Company.

(m)  Cooperate with the sellers of Registrable Shares and the managing underwriter, if any, to facilitate the timely preparation and delivery of certificates not bearing any

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restrictive legends representing the Registrable Shares to be sold, and cause such Registrable Shares to be issued in such denominations and registered in such names in accordance with the underwriting agreement prior to any sale of Registrable Shares to the underwriters or, if not an underwritten offering, in accordance with the instructions of the sellers of Registrable Shares at least three business days prior to any sale of Registrable Shares and instruct any transfer agent and registrar of Registrable Shares to release any stop transfer orders in respect thereof.

(n)  Take all such other commercially reasonable actions as are necessary or advisable in order to expedite or facilitate the disposition of such Registrable Shares.

(o)  (A) Include in such registration statement and prospectus any information or disclosure related to a Holder as a selling stockholder thereunder reasonably requested by such Holder as may be necessary in the opinion of counsel to such Holder to ensure compliance with applicable securities laws and (B) consider in good faith whether or not to include in such registration statement and prospectus any information or disclosure not related to a Holder as a selling stockholder thereunder reasonably requested by such Holder as may be necessary in the opinion of counsel to such Holder to ensure compliance with applicable securities laws.

(p)  Take all reasonable action to ensure that any free writing prospectus prepared, authorized or approved by the Company and utilized in connection with any registration complies in all material respects with the Securities Act, is filed in accordance with the Securities Act to the extent required thereby, and is retained in accordance with the Securities Act to the extent required thereby.

If the Company has delivered a prospectus to the selling Holders of Registrable Shares and after having done so such prospectus is amended to comply with the requirements of the Securities Act, the Company shall promptly notify the selling Holders of Registrable Shares and, if requested, the selling Holders of Registrable Shares shall immediately cease making offers of Registrable Shares and return all prospectuses to the Company.  The Company shall promptly provide the selling Holders of Registrable Shares with revised prospectuses and, following receipt of the revised prospectuses, the selling Holders of Registrable Shares shall be free to resume making offers of the Registrable Shares.

No Holder shall have any right to take any action to restrain, enjoin, or otherwise delay any registration as the result of any controversy that might arise with respect to the interpretation or implementation of this Agreement.

4.              Furnish Information.

(a)  It shall be a condition precedent to the obligations of the Company to take any action pursuant to this Agreement with respect to the registration of any Holder’s Registrable Shares that such Holder shall take such actions and furnish to the Company such information regarding itself, the Registrable Shares held by it, and the intended method of disposition of such securities, as may then be customarily provided by selling stockholders as the Company shall reasonably request and as shall be required in connection with any registration, qualification or compliance referred to in this Agreement, including, without limitation (i) in connection with an underwritten offering, enter into an appropriate underwriting agreement containing terms and provisions then customary in agreements of that nature (it being understood that the Holders of

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the Registrable Shares which are to be distributed by any underwriters may, at their option, require that any or all of the conditions precedent to the obligations of such underwriters under such underwriting agreement shall be conditions precedent to the obligations of such Holder), (ii) enter into such custody agreements, powers of attorney and related documents at such time and on such terms and conditions as may then be customarily required in connection with such offering and (iii) distribute the Registrable Shares only in accordance with and in the manner of the distribution contemplated by the applicable registration statement and prospectus.  In addition, the Holders shall promptly notify the Company of any request by the SEC or any state securities commission or agency for additional information or for such registration statement or prospectus to be amended or supplemented.

(b)  If any such registration statement or comparable statement under "blue sky" laws refers to any Holder by name or otherwise as the Holder of any securities of the Company, then such Holder shall have the right to require (i) the insertion therein of language, in form and substance reasonably satisfactory to such Holder and the Company, to the effect that the holding by such Holder of such securities is not to be construed as a recommendation by such Holder of the investment quality of the Company’s securities covered thereby and that such holding does not imply that such Holder will assist in meeting any future financial requirements of the Company, or (ii) in the event that such reference to such Holder by name or otherwise is not in the judgment of the Company, as advised by counsel, required by the Securities Act or any similar federal statute or any state "blue sky" or securities law then in force, the deletion of the reference to such Holder.

(c)  The Company covenants that (i)  so long as it remains subject to the reporting provisions of the Exchange Act, it will timely file the reports required to be filed by it under the Securities Act or the Exchange Act (including, but not limited to, the reports under Sections 13 and 15(d) of the Exchange Act referred to in subparagraph (c)(1) of Rule 144 under the Securities Act), and (ii) will take such further action as any Holder of Registrable Shares may reasonably request, all to the extent required from time to time to enable such Holder to sell Registrable Shares without registration under the Securities Act within the limitation of the exemptions provided by (A) Rule 144 under the Securities Act, as such Rule may be amended from time to time, or (B) any similar rule or regulation hereafter adopted by the SEC.  Upon the request of any Holder of Registrable Shares, the Company will deliver to such Holder a written statement as to whether it has complied with such requirements.

5.              Underwriting Requirements; Company Registration.

(a)  In connection with any offering under Section 2 involving an underwriting of shares being issued by the Company, the Company shall not be required to include any Holder’s Registrable Shares in such underwriting unless such Holder accepts the terms of the underwriting as agreed upon between the Company and the underwriters selected by it (and enters into an underwriting agreement with the underwriters on customary terms) (it being understood that the Holders of the Registrable Shares which are to be distributed by any underwriters may, at their option, require that any or all of the conditions precedent to the obligations of such underwriters under such underwriting agreement shall be conditions precedent to the obligations of such Holder), and then only in such quantity as will not, in the reasonable opinion of the underwriters, jeopardize the success of the offering by the Company.  If the total amount of securities, including Registrable Shares, requested by stockholders to be included in such offering exceeds

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the amount of securities to be sold (other than by the Company) that the underwriters determine in their sole discretion is compatible with the success of the offering, then the Company shall be required to include in the offering only that number of such securities, including Registrable Shares, which the underwriters determine in their sole discretion will not jeopardize the success of the offering; provided, however, there shall first be excluded from such registration statement all shares of Common Stock sought to be included therein by (i) any director, consultant, officer, or employee of the Company or any subsidiary of the Company other than Ram Sasisekharan, Robert S. Langer, Jr., Ganesh Venkataraman and Alan L. Crane, (ii) stockholders exercising any contractual or incidental registration rights subordinate and junior to the rights of the Preferred Holders of Registrable Securities (each as defined in the Existing Registration Rights Agreement) and the Holders and (iii) stockholders who do not have contractual registration rights.  If after such shares are excluded and any Registrable Shares remain to be included in the offering, the underwriters shall determine in their sole discretion that the number of securities which remain to be included in the offering exceeds the amount of securities to be sold that the underwriters determine is compatible with the success of the offering, then (a) in the context of a Section 2 offering, prior to excluding any shares for the account of one or more securityholders party to the Existing Registration Rights Agreement, the Company shall first exclude, on a pro rata basis, that number of Registrable Shares and securities to be registered for the account of holders of registration rights granted after the date hereof which the underwriters determine in their sole discretion will jeopardize the success of the offering and (b) in the context of a Section 7 offering, prior to excluding any shares for the account of any Holder, all securities to be registered for the account of holders of registration rights granted after the date hereof shall be excluded from such registration statement.  Any Registrable Shares to be included in the offering shall be apportioned pro rata among the Holders providing notice of their desire to participate in the offering according to the total amount of securities entitled to be included therein owned by each selling Holder or in such other proportions as shall mutually be agreed to by such Holders.  For purposes of the preceding two sentences and the last sentence of the following paragraph concerning apportionment, for any selling Holder or other stockholder which is a partnership, limited liability company or corporation, the partners, members, retired members, retired partners, and stockholders of such Holder or stockholder, or the estates and family members of any such partners, members, retired members and retired partners and any trusts for the benefit of any of the foregoing Persons shall be deemed to be a single "selling Holder" or "selling stockholder" and any pro rata reduction with respect to such "selling Holder" or "selling stockholder" shall be based upon the aggregate amount of shares carrying registration rights owned by all entities and individuals included in such "selling Holder" or "selling stockholder," as defined in this sentence.

(b)  If the total amount of securities requested by stockholders to be included in an offering for the account of one or more securityholders party to the Existing Registration Rights Agreement, including Registrable Shares so requested to be included in such offering, exceeds the amount of securities to be sold that the underwriters determine in their sole discretion is compatible with the success of the offering, then all Registrable Shares shall be excluded from such registration statement.  Any Registrable Shares to be included in the offering shall be apportioned pro rata among the Holders providing notice of their desire to participate in the offering according to the total amount of securities entitled to be included therein owned by each selling Holder or in such other proportions as shall mutually be agreed to by such Holders.

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(c)  If, as a result of the proration provisions of this Section, any Holder shall not be entitled to include all Registrable Shares in a registration that such Holder has requested be included, such Holder may elect to withdraw its request to include Registrable Shares in such registration or may reduce the number requested to be included; provided, however, that (x) such request must be made in writing prior to the earlier of the execution of the underwriting agreement or the execution of the custody agreement with respect to such registration and (y) such withdrawal shall be irrevocable and, after making such withdrawal, such Holder shall no longer have any right to include Registrable Shares in the registration as to which such withdrawal was made.

(d)  In connection with any underwritings of shares to be registered under Section 2, the Company shall have the right to designate the managing underwriter or underwriters.

6.              Company Registration Expenses.   All expenses incurred in connection with any registration pursuant to Section 2, including, without limitation, any additional registration and qualification fees and any additional fees and disbursements of counsel to the Company that result from