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TABLE OF CONTENTS

Table of Contents

As filed with the Securities and Exchange Commission on December 9, 2009

Registration No. 333-            

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, DC 20549



FORM S-3
REGISTRATION STATEMENT UNDER
THE SECURITIES ACT OF 1933



MOMENTA PHARMACEUTICALS, INC.
(Exact Name of Registrant as Specified in Its Charter)

Delaware
(State or Other Jurisdiction of Incorporation or Organization)
  04-3561634
(I.R.S. Employer Identification Number)

675 West Kendall Street
Cambridge, MA 02142
(617) 491-9700

(Address, Including Zip Code, and Telephone Number, Including Area Code, of Registrant's Principal Executive Offices)



Craig A. Wheeler
Momenta Pharmaceuticals, Inc.
675 West Kendall Street
Cambridge, MA 02142
(617) 491-9700

(Name, Address, Including Zip Code, and Telephone Number, Including Area Code, of Agent for Service)



Copy to:

Steven D. Singer, Esq.
Wilmer Cutler Pickering Hale and Dorr LLP
60 State Street
Boston, Massachusetts 02109
Telephone: (617) 526-6000
Telecopy: (617) 526-5000



Approximate date of commencement of proposed sale to public:
From time to time after this Registration Statement becomes effective.

             If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box. o

             If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box. ý

             If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

             If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

             If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box. o

             If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box. o

             Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of "large accelerated filer," "accelerated filer" and "smaller reporting company" in Rule 12b-2 of the Exchange Act. (Check one):

Large accelerated filer o   Accelerated filer ý   Non-accelerated filer o
(Do not check if a smaller
reporting company)
  Smaller reporting company o



CALCULATION OF REGISTRATION FEE

 
Title of each class of securities
to be registered(1)

  Amount to be
registered(1)

  Proposed maximum
offering price per
unit(2)(3)

  Proposed maximum
aggregate offering
price(2)(3)

  Amount of
registration fee(4)

 
Common stock, $0.0001 par value per share     (6)                           (6)              (6)
 
Preferred stock, $0.01 par value per share     (6)                           (6)              (6)
 
Debt securities     (6)                           (6)              (6)
 
Warrants     (6)                           (6)              (6)
 
Total           $74,650,000   $4,166(5)
 
(1)
There are being registered hereunder such indeterminate number of shares of common stock, such indeterminate number of shares of preferred stock, such indeterminate principal amount of debt securities, and such indeterminate number of warrants to purchase common stock, preferred stock or debt securities, as shall have an aggregate initial offering price not to exceed $150,000,000, consisting of $75,350,000 of unsold securities that had previously been registered and $74,650,000 of additional securities registered on this registration statement. If any debt securities are issued at an original issue discount, then the offering price of such debt securities shall be in such greater principal amount as shall result in an aggregate initial offering price not to exceed $150,000,000, less the aggregate dollar amount of all securities previously issued hereunder. Any securities registered hereunder may be sold separately or as units with other securities registered hereunder. The securities registered also include such indeterminate amounts and numbers of shares of common stock and numbers of shares of preferred stock, and principal amounts of debt securities, as may be issued upon conversion of or exchange for preferred stock or debt securities that provide for conversion or exchange, upon exercise of warrants or pursuant to the antidilution provisions of any such securities.

(2)
In United States dollars or the equivalent thereof in any other currency, currency unit or units, or composite currency or currencies.

(3)
The proposed maximum per unit and aggregate offering prices per class of security will be determined from time to time by the registrant in connection with the issuance by the registrant of the securities registered hereunder.

(4)
Estimated solely for purposes of determining the registration fee pursuant to Rule 457(o) under the Securities Act of 1933.

(5)
Pursuant to Rule 415(a)(6) under the Securities Act, this registration statement includes a total of $75,350,000 of unsold securities that had previously been registered under the Registrant's registration statement on Form S-3 initially filed on January 26, 2007 and amended on February 7, 2007, file number 333-140251 (the "Prior Registration Statement"). The Prior Registration Statement registered securities for a maximum offering price of $150,000,000. The Registrant sold an aggregate of $74,650,000 of securities thereunder, leaving a balance of unsold securities with an aggregate offering price of $75,350,000. In connection with the registration of such unsold securities on the Prior Registration Statement, the Registrant paid a registration fee of $8,062 for such unsold securities, which fee will continue to be applied to such unsold securities. Accordingly, the amount of the registration fee has been calculated based on the proposed maximum offering price of the additional $74,650,000 of securities registered on this registration statement. Pursuant to Rule 415(a)(6), the offering of the unsold securities registered under the Prior Registration Statement will be deemed terminated as of the date of effectiveness of this registration statement.

(6)
Not required to be included in accordance with General Instruction II.D. of Form S-3.

             The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment which specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.


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The information in this prospectus is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell these securities and it is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

Subject to Completion, dated December 9, 2009

PROSPECTUS

$150,000,000

MOMENTA PHARMACEUTICALS, INC.

Common Stock
Preferred Stock
Debt Securities
Warrants



        We may from time to time issue up to $150,000,000 aggregate principal amount of common stock, preferred stock, debt securities and warrants. We may sell these securities to or through underwriters, directly to investors or through agents. We will specify the terms of the securities, and the names of any underwriters or agents, in supplements to this prospectus.

        Our common stock is listed on the Nasdaq Global Market and traded under the symbol "MNTA." The last reported sale price of our common stock on the Nasdaq Global Market on December 8, 2009 was $10.63 per share.



        Investing in our securities involves risks. See "Risk Factors" at page 3 of this prospectus.



        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus. Any representation to the contrary is a criminal offense.



        This prospectus may not be used to consummate sales of securities unless it is accompanied by a prospectus supplement.



        Prospectus dated                        ,        .


Table of Contents


TABLE OF CONTENTS

 
  Page

ABOUT THIS PROSPECTUS

  1

SPECIAL NOTE REGARDING FORWARD-LOOKING INFORMATION

  1

MOMENTA PHARMACEUTICALS, INC. 

  2

RISK FACTORS

  3

USE OF PROCEEDS

  3

RATIO OF EARNINGS TO FIXED CHARGES

  3

DILUTION

  3

THE SECURITIES WE MAY OFFER

  4

DESCRIPTION OF CAPITAL STOCK

  5

DESCRIPTION OF DEBT SECURITIES

  8

DESCRIPTION OF WARRANTS

  14

LEGAL OWNERSHIP OF SECURITIES

  16

PLAN OF DISTRIBUTION

  20

LEGAL MATTERS

  21

EXPERTS

  22

WHERE YOU CAN FIND MORE INFORMATION

  22

INCORPORATION OF DOCUMENTS BY REFERENCE

  22



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ABOUT THIS PROSPECTUS

        This prospectus is part of a registration statement that we filed with the Securities and Exchange Commission, which we refer to as the SEC, utilizing a "shelf" registration process. Under this shelf registration process, we may from time to time sell any combination of the securities described in this prospectus in one or more offerings up to a total dollar amount of $150,000,000. We may offer any of the following securities: common stock, preferred stock and debt securities. We may also offer warrants to purchase common stock, preferred stock and debt securities.

        This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide one or more prospectus supplements that will contain specific information about the terms of the offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and the accompanying prospectus supplement together with the additional information described under the headings "Where You Can Find More Information" and "Incorporation of Documents by Reference" below.

        You should rely only on the information contained in or incorporated by reference in this prospectus, any accompanying prospectus supplement or in any related free writing prospectus filed by us with the SEC. We have not authorized anyone to provide you with different information. This prospectus and the accompanying prospectus supplement do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the securities described in the accompanying prospectus supplement or an offer to sell or the solicitation of an offer to buy such securities in any circumstances in which such offer or solicitation is unlawful. You should assume that the information appearing in this prospectus, any prospectus supplement and the documents incorporated by reference is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed materially since those dates.

        The terms "we," "us," "our," "Momenta," the "Company" and similar designations refer to Momenta Pharmaceuticals, Inc.

        Our logo, trademarks and service marks are the property of Momenta. Other trademarks or service marks appearing in this prospectus are the property of their respective holders.


SPECIAL NOTE REGARDING FORWARD-LOOKING INFORMATION

        Statements, other than statements of historical facts, that we include in this prospectus, any prospectus supplement and the documents we incorporate by reference in this prospectus, may be deemed "forward looking statements" within the meaning of Section 27A of the Securities Act of 1933, as amended, or the Securities Act, and Section 21E of the Securities Exchange Act of 1934, as amended, or the Exchange Act. We use the words "anticipate," "believe," "could," "could increase the likelihood," "hope," "target," "project," "goals," "potential," "predict," "might," "estimate," "expect," "intend," "is planned," "may," "should," "will," "will enable," "would be expected," "look forward," "may provide," "would" or similar terms, variations of such terms or the negative of those terms, to identify forward looking statements, although not all forward looking statements contain these identifying words. We cannot guarantee that we actually will achieve the plans, intentions or expectations disclosed in our forward looking statements and, accordingly, you should not place undue reliance on our forward looking statements. There are a number of important factors that could cause actual results or events to differ materially from the forward looking statements that we make, including the factors included in the documents we incorporate by reference herein. You should read these factors and the other cautionary statements made in the documents we incorporate by reference as being applicable to all related forward-looking statements wherever they appear in this prospectus, any prospectus supplement, and any document incorporated by reference. We caution you that we do not undertake any obligation to update or revise forward looking statements made by us, whether as a result of new information, future events or otherwise.

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MOMENTA PHARMACEUTICALS, INC.

        Momenta is a biotechnology company with a product pipeline of both complex generic and novel drugs. This pipeline is derived from our proprietary, innovative technology platform for the detailed structural analysis of complex mixture drugs. We use this platform to study the structure (thorough characterization of chemical components), structure-process (design and control of manufacturing process), and structure-activity (relating structure to biological and clinical activity) of complex mixture drugs.

        Our complex mixture generics and follow-on biologics effort is focused on building a thorough understanding of the structure-process-activity of complex mixture drugs to develop generic versions of marketed products. While we use a similar analytical and development approach across all of our product candidates, we tailor that approach for each specific product candidate. Our first objective is to apply our core analytical technology to thoroughly characterize the structure of the marketed product. By defining the chemical composition of multiple batches of the marketed product, we are able to develop an equivalence window, which captures the inherent variability of the innovator's manufacturing process. Using this information we then build an extensive understanding of the structure-process relationship to design and control our manufacturing process to reproducibly manufacture an equivalent version of the marketed product. Where necessary, and as required by the U.S. Food and Drug Administration, or FDA, we will supplement an application with additional supportive structure-activity data (e.g., immunogenicity, pharmacodynamics). Our goal is to obtain FDA approval for and commercialize generic or follow-on versions of complex mixture products, thereby providing high quality, safe and affordable medicines to patients in need.

        Our complex mixture novel drug research and development efforts leverage our analytical technology platform and structure-process knowledge to develop novel drugs by studying the structure-activity of complex mixtures. With our capabilities to thoroughly characterize complex mixtures, we are targeting our efforts to understand the relationship between structure and the biological and therapeutic activity of various complex mixture drug candidates. Our goal is to capitalize on the structural diversity and multitargeting potential of these complex mixtures to engineer novel drug candidates that we believe will meet key unmet medical needs in various diseases. While we believe that our capabilities to engineer improved and novel complex mixture drug candidates can be applied across several product categories with significant therapeutic potential, such as polysaccharides, polypeptides and glycoproteins, our initial focus has been in the area of complex polysaccharide mixtures.

        We were incorporated in Delaware in May 2001 under the name Mimeon, Inc. In September 2002, we changed our name to Momenta Pharmaceuticals, Inc. Our principal executive offices are located at 675 West Kendall Street, Cambridge, Massachusetts 02142, and our telephone number is (617) 491-9700. Our Internet address is www.momentapharma.com. The information on our website is not incorporated by reference into this prospectus and should not be considered to be a part of this prospectus. We have included our website address as an inactive textural reference only.

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RISK FACTORS

        Investing in our securities involves risk. Please see the risk factors under the heading "Risk Factors" in our most recent annual report on Form 10-K, as revised or supplemented by our quarterly reports on Form 10-Q filed with the SEC since the filing of our most recent annual report on Form 10-K, all of which are on file with the SEC and are incorporated herein by reference in this prospectus. Before making an investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus and any prospectus supplement. The risks and uncertainties we have described are not the only ones facing our company. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our business operations.


USE OF PROCEEDS

        Unless otherwise provided in the applicable prospectus supplement, we intend to use the net proceeds from the sale of the securities under this prospectus for general corporate purposes, including clinical trial costs, research and development expenses, manufacturing expenses, general and administrative expenses, and potential acquisitions of companies, products and technologies that complement our business. We will set forth in the prospectus supplement our intended use for the net proceeds received from the sale of any securities. Pending the application of the net proceeds, we intend to invest the net proceeds in investment-grade, interest-bearing securities.


RATIO OF EARNINGS TO FIXED CHARGES

        We did not record earnings for any of the years ended December 31, 2008, 2007, 2006, 2005 or 2004 or for the nine-month period ended September 30, 2009. Accordingly, our earnings were insufficient to cover fixed charges in such periods and we are unable to disclose a ratio of earnings to fixed charges. The following table sets forth, for each of the periods presented, the dollar amount of the deficiency of earnings available to cover fixed charges. For purposes of computing the deficiency of earnings available to cover fixed charges, fixed charges represent interest expense, an estimate of the interest expense within rental expense, the non-cash dividend related to the beneficial conversion feature of our Series C redeemable convertible preferred stock and the accretion to redemption value of the redeemable convertible preferred stock.

 
  Nine Month
Period
Ended,
September 30,
  Year Ended December 31,  
In thousands
  2009   2008   2007   2006   2005   2004  

Deficiency of Earnings to Cover Fixed Charges

  $ 49,323   $ 62,637   $ 68,881   $ 51,913   $ 21,662   $ 36,316  
                           


DILUTION

        We will set forth in a prospectus supplement the following information regarding any material dilution of the equity interests of investors purchasing securities in an offering under this prospectus:

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THE SECURITIES WE MAY OFFER

        The descriptions of the securities contained in this prospectus, together with the applicable prospectus supplements, summarize all the material terms and provisions of the various types of securities that we may offer. We will describe in the applicable prospectus supplement relating to any securities the particular terms of the securities offered by that prospectus supplement. If we indicate in the applicable prospectus supplement, the terms of the securities may differ from the terms we have summarized below. We will also include in the prospectus supplement information, where applicable, about material United States federal income tax considerations relating to the securities, and the securities exchange, if any, on which the securities will be listed.

        We may sell from time to time, in one or more offerings:

        In this prospectus, we refer to the common stock, preferred stock, debt securities and warrants collectively as "securities." The total dollar amount of all securities that we may sell will not exceed $150,000,000.

        If we issue debt securities at a discount from their original stated principal amount, then, for purposes of calculating the total dollar amount of all securities issued under this prospectus, we will treat the initial offering price of the debt securities as the total original principal amount of the debt securities.

        This prospectus may not be used to consummate a sale of securities unless it is accompanied by a prospectus supplement.

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DESCRIPTION OF CAPITAL STOCK

        Under our certificate of incorporation, we are authorized to issue 100,000,000 shares of common stock, par value $0.0001 per share, and 5,000,000 shares of preferred stock, par value $0.01 per share. The following description summarizes information about our capital stock. You can obtain more comprehensive information about our capital stock by consulting our certificate of incorporation and by-laws, each as amended to date, as well as the Delaware General Corporation Law.

Common Stock

        Holders of our common stock are entitled to one vote for each share held on all matters submitted to a vote of stockholders and do not have cumulative voting rights. Accordingly, holders of a majority of the shares of common stock entitled to vote in any election of directors may elect all of the directors standing for election. Holders of common stock are entitled to receive proportionately any dividends as may be declared by our board of directors, subject to any preferential dividend rights of outstanding preferred stock.

        In the event of our liquidation, dissolution or winding up, the holders of our common stock are entitled to receive proportionately our net assets available after the payment of all debts and other liabilities and subject to the prior rights of any outstanding preferred stock. Holders of our common stock have no preemptive, subscription, redemption or conversion rights. The rights, preferences and privileges of holders of common stock are subject to and may be adversely affected by, the rights of the holders of shares of any series of preferred stock that we may designate and issue in the future.

        The transfer agent and registrar for our common stock is American Stock Transfer & Trust Co.

Preferred Stock

        Under the terms of our certificate of incorporation, our board of directors is authorized to direct us to issue shares of preferred stock in one or more series without stockholder approval. Our board of directors has the discretion to determine the rights, preferences, privileges and restrictions, including voting rights, dividend rights, conversion rights, redemption privileges and liquidation preferences of each series of preferred stock. We have designated one series of preferred stock. See "—Series A Preferred Stock" below.

        The purpose of authorizing our board of directors to issue preferred stock and determine its rights and preferences is to eliminate delays associated with a stockholder vote on specific issuances. The issuance of preferred stock, while providing flexibility in connection with possible acquisitions, future financings and other corporate purposes, could have the effect of making it more difficult for a third party to acquire, or could discourage a third party from seeking to acquire, a majority of our outstanding voting stock.

        The preferred stock of each series will rank senior to the common stock and the Series A Junior Participating Preferred Stock in priority of payment of dividends and in the distribution of assets in the event of our liquidation, dissolution or winding up, to the extent of the preferential amounts to which the preferred stock of the respective series will be entitled. Upon issuance, the shares of preferred stock will be fully paid and nonassessable, which means that its holders will have paid their purchase price in full and we may not require them to pay additional funds.

        On October 31, 2005, in connection with the adoption of a rights plan, which has subsequently expired, our board of directors designated 100,000 shares of preferred stock as Series A Junior Participating Preferred Stock, $0.01 par value per share, or Series A preferred stock, as set forth in the

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Certificate of Designations of Series A Junior Participating Preferred Stock filed with the Secretary of State of the State of Delaware on November 8, 2005.

Anti-Takeover Effects of Provisions of Delaware Law and Our Charter and By-Laws

        We are subject to Section 203 of the Delaware General Corporation Law. Subject to certain exceptions, Section 203 prevents a publicly-held Delaware corporation from engaging in a "business combination" with any "interested stockholder" for three years following the date that the person became an interested stockholder, unless the interested stockholder attained such status with the approval of our board of directors or unless the business combination is approved in a prescribed manner. A "business combination" includes, among other things, a merger or consolidation involving us, and the interested stockholder and the sale of more than 10% of our assets. In general, an "interested stockholder" is any entity or person beneficially owning 15% or more of our outstanding voting stock and any entity or person affiliated with or controlling or controlled by such entity or person.

        Our certificate of incorporation provides that the directors elected may be removed only for cause and only by the affirmative vote of the holders of at least 75% of the votes which all our stockholders would be entitled to cast in any annual election of directors. Under our certificate of incorporation, any vacancy or newly created directorships on the board of directors can be filled only by vote of a majority of our directors then in office. The limitations on the ability of our stockholders to remove directors and fill vacancies could make it more difficult for a third party to acquire, or discourage a third party from seeking to acquire, control of our company.

        Our certificate of incorporation provides that any action required or permitted to be taken by our stockholders at an annual meeting or special meeting of stockholders may only be taken if it is properly brought before such meeting and may not be taken by written action in lieu of a meeting. Our certificate of incorporation and our by-laws also provide that, except as otherwise required by law, special meetings of the stockholders can only be called by our chief executive officer, president, our chairman of the board, or a majority of our board of directors. In addition, our by-laws establish an advance notice procedure for stockholder proposals to be brought before an annual meeting of stockholders, including proposed nominations of candidates for election to our board of directors. Stockholders at an annual meeting may only consider proposals or nominations specified in the notice of meeting or brought before the meeting by or at the direction of our board of directors or by a stockholder of record on the record date for the meeting, who is entitled to vote at the meeting and who has delivered timely written notice in proper form to our secretary of the stockholder's intention to bring such business before the meeting. These provisions could have the effect of delaying stockholder actions that are favored by the holders of a majority of our outstanding voting securities until the next stockholder meeting.

        The Delaware General Corporation Law provides generally that the affirmative vote of a majority of the shares entitled to vote on any matter is required to amend a corporation's certificate of incorporation or by-laws, unless a corporation's certificate of incorporation or by-laws, as the case may be, requires a greater percentage. Our by-laws may be amended or repealed by a majority vote of our board of directors or by the affirmative vote of the holders of at least 75% of the votes which all our stockholders would be entitled to cast in any annual election of directors.

Potential Effects of Authorized but Unissued Stock

        We have shares of common stock and preferred stock available for future issuance without stockholder approval. We may utilize these additional shares for a variety of corporate purposes, including future public offerings to raise additional capital, to facilitate corporate acquisitions or payment as a dividend on the capital stock.

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        The existence of unissued and unreserved common stock and preferred stock may enable the board of directors to issue shares to persons friendly to current management or to issue preferred stock with terms that could render more difficult or discourage a third-party attempt to obtain control of us by means of a merger, tender offer, proxy contest or otherwise, thereby protecting the continuity of our management. In addition, the board has the discretion to determine designations, rights, preferences, privileges and restrictions, including voting rights, dividend rights, conversion rights, redemption privileges and liquidation preferences of each series of preferred stock, all to the fullest extent permissible under the Delaware General Corporation Law and subject to any limitations set forth in our certificate of incorporation. The purpose of authorizing the board to issue preferred stock and to determine the rights and preferences applicable to such preferred stock is to eliminate delays associated with a stockholder vote on specific issuances. The issuance of preferred stock, while providing desirable flexibility in connection with possible financings, acquisitions and other corporate purposes, could have the effect of making it more difficult for a third party to acquire, or could discourage a third party from acquiring, a majority of our outstanding voting stock.

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DESCRIPTION OF DEBT SECURITIES

        The following description, together with the additional information we include in any applicable prospectus supplement, summarizes the material terms and provisions of the debt securities that we may offer under this prospectus. While the terms we have summarized below will apply generally to any future debt securities we may offer, we will describe the particular terms of any debt securities that we may offer in more detail in the applicable prospectus supplement. If we indicate in a prospectus supplement, the terms of any debt securities we offer under that prospectus supplement may differ from the terms we describe below.

        We will issue senior debt securities under a senior indenture which we will enter into with a trustee to be named in the senior indenture. We will issue subordinated debt securities under a subordinated indenture which we will enter into with a trustee to be named in the subordinated indenture. We have filed forms of these documents as exhibits to the registration statement which includes this prospectus. We use the term "indentures" to refer to both the senior indenture and the subordinated indenture. The indentures will be qualified under the Trust Indenture Act of 1939, or the Trust Indenture Act. We use the term "trustee" to refer to either the senior trustee or the subordinated trustee, as applicable.

        The following summaries of material provisions of senior debt securities, subordinated debt securities and the indentures are subject to, and qualified in their entirety by reference to, the provisions of the indenture applicable to a particular series of debt securities. Except as we may otherwise indicate, the terms of the senior indenture and the subordinated indenture are identical.

General

        We will describe in the applicable prospectus supplement the following terms relating to a series of debt securities:

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Conversion or Exchange Rights

        We will set forth in the applicable prospectus supplement the terms on which a series of debt securities may be convertible into or exchangeable for common stock or other securities of ours. We will include provisions as to whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of shares of common stock or other securities of ours that the holders of the series of debt securities receive would be subject to adjustment.

Consolidation, Merger or Sale

        The indentures do not contain any covenant which restricts our ability to merge or consolidate, or sell, convey, transfer or otherwise dispose of all or substantially all of our assets. However, any successor to or acquirer of such assets must assume all of our obligations under the indentures or the debt securities, as appropriate, and immediately after giving effect to the transaction, no default or event of default shall have occurred and be continuing.

Events of Default under the Indenture

        The following are events of default under the indentures with respect to any series of debt securities that we may issue:

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        If an event of default, other than an event of default specified in the last bullet point, with respect to debt securities of any series occurs and is continuing, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to us in writing, and to the trustee if notice is given by such holders, may declare the unpaid principal of, or premium, if any, on and accrued interest, if any, on the debt securities due and payable immediately. If an event of default specified in the last bullet point occurs and is continuing, the entire principal amount of, and accrued interest, if any, on each series of debt securities then outstanding shall become immediately due and payable.

        The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except defaults or events of default regarding payment of principal, or premium, if any, or interest, unless we have cured the default or event of default in accordance with the indenture. Any waiver shall cure the default or event of default.

        Subject to the terms of the indentures, if an event of default under an indenture shall occur and be continuing, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the applicable series of debt securities, unless such holders have offered the trustee reasonable indemnity. The holders of a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities of that series, provided that:

        A holder of the debt securities of any series will only have the right to institute a proceeding under the indentures or to appoint a receiver or trustee, or to seek other remedies, if:

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        These limitations do not apply to a suit instituted by a holder of debt securities if we default in the payment of the principal of, or the premium, if any, or interest on, the debt securities.

        We will periodically file statements with the trustee regarding our compliance with specified covenants in the indentures.

Modification of Indenture; Waiver

        We and the trustee may change an indenture without the consent of any holders with respect to specific matters, including:

        In addition, under the indentures, the rights of holders of a series of debt securities may be changed by us and the trustee with the written consent of the holders of at least a majority in aggregate principal amount of the outstanding debt securities of each series that is affected. However, we and the trustee may only make the following changes with the consent of each holder of any outstanding debt securities affected:

Discharge

        Each indenture provides that we can elect, under certain circumstances, to be discharged from our obligations with respect to one or more series of debt securities, except for obligations to:

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        In order to exercise our rights to be discharged, we must deposit with the trustee money or government obligations sufficient to pay all the principal of, any premium, if any, and interest on, the debt securities of the series on the dates payments are due.

Form, Exchange and Transfer

        We will issue the debt securities of each series only in fully registered form without coupons and, unless we otherwise specify in the applicable prospectus supplement, in denominations of $1,000 and any integral multiple thereof. The indentures provide that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with, or on behalf of, The Depository Trust Company, New York, New York, or DTC, or another depository named by us and identified in a prospectus supplement with respect to that series. See "Legal Ownership of Securities" for a further description of the terms relating to any book-entry securities.

        At the option of the holder, subject to the terms of the indentures and the limitations applicable to global securities described in the applicable prospectus supplement, the holder of the debt securities of any series can exchange the debt securities for other debt securities of the same series, in any authorized denomination and of like tenor and aggregate principal amount.

        Subject to the terms of the indentures and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, we will not require any payment for any registration of transfer or exchange, but we may require payment of any taxes or other governmental charges.

        We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for the debt securities of each series.

        If we elect to redeem the debt securities of any series, we will not be required to:

Information Concerning the Trustee

        The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the trustee must use the same degree of care

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and skill as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the trustee is under no obligation to exercise any of the powers given to it by the indentures at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.

Payment and Paying Agents

        Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest payment.

        We will pay principal of and any premium and interest on the debt securities of a particular series at the office of the paying agents designated by us, except that unless we otherwise indicate in the applicable prospectus supplement, we will make interest payments by check which we will mail to the holder. Unless we otherwise indicate in a prospectus supplement, we will designate the corporate trust office of the trustee in The City of New York as our sole paying agent for payments with respect to debt securities of each series. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series. We will maintain a paying agent in each place of payment for the debt securities of a particular series.

        All money we pay to a paying agent or the trustee for the payment of the principal of or any premium or interest on any debt securities which remains unclaimed at the end of two years after such principal, premium or interest has become due and payable will be repaid to us, and the holder of the security thereafter may look only to us for payment thereof.

Governing Law

        The indentures and the debt securities will be governed by and construed in accordance with the laws of the State of New York, except to the extent that the Trust Indenture Act is applicable.

Subordination of Subordinated Debt Securities

        Other than the terms of the subordinated indenture and subordinated debt securities relating to subordination or as otherwise described in the applicable prospectus supplement, the terms of the subordinated indenture and subordinated debt securities are identical in all material respects to the terms of the senior indenture and senior debt securities.

        The subordinated debt securities will be unsecured and will be subordinate and junior in priority of payment to certain of our other indebtedness to the extent described in a prospectus supplement. The subordinated indenture does not limit the amount of subordinated debt securities which we may issue. It also does not limit us from issuing any other secured or unsecured debt.

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DESCRIPTION OF WARRANTS

        The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the warrants that we may offer under this prospectus and the related warrant agreements and warrant certificates. While the terms summarized below will apply generally to any warrants that we may offer, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any warrants offered under that prospectus supplement may differ from the terms described below. Specific warrant agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement that includes this prospectus.

General

        We may issue warrants for the purchase of common stock, preferred stock or debt securities in one or more series. We may issue warrants independently or together with common stock, preferred stock and debt securities, and the warrants may be attached to or separate from these securities.

        We will evidence each series of warrants by warrant certificates that we will issue under a separate agreement. We will enter into the warrant agreement with a warrant agent. Each warrant agent will be a bank that we select, which has its principal office in the United States and a combined capital and surplus of at least $50,000,000. We will indicate the name and address of the warrant agent in the applicable prospectus supplement relating to a particular series of warrants.

        Before exercising their warrants, holders of warrants will not have any of the rights of holders of the securities purchasable upon such exercise, including:

Additional Information

        We will describe in the applicable prospectus supplement the terms of the series of warrants, including:

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Exercise of Warrants

        Each warrant will entitle the holder to purchase the securities that we specify in the applicable prospectus supplement at the exercise price that we describe in the applicable prospectus supplement. Unless we otherwise specify in the applicable prospectus supplement, holders of the warrants may exercise the warrants at any time up to 5 p.m., Eastern Time, on the expiration date that we set forth in the applicable prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void.

        Holders of the warrants may exercise the warrants by delivering the warrant certificate representing the warrants to be exercised together with specified information, and paying the required amount to the warrant agent in immediately available funds, as provided in the applicable prospectus supplement. We will set forth on the reverse side of the warrant certificate and in the applicable prospectus supplement the information that the holder of the warrant will be required to deliver to the warrant agent.

        Upon receipt of the required payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will issue and deliver the securities purchasable upon such exercise. If fewer than all of the warrants represented by the warrant certificate are exercised, then we will issue a new warrant certificate for the remaining amount of warrants. If we so indicate in the applicable prospectus supplement, holders of the warrants may surrender securities as all or part of the exercise price for warrants.

Enforceability of Rights by Holders of Warrants

        Each warrant agent will act solely as our agent under the applicable warrant agreement and will not assume any obligation or relationship of agency or trust with any holder of any warrant. A single bank or trust company may act as warrant agent for more than one issue of warrants. A warrant agent will have no duty or responsibility in case of any default by us under the applicable warrant agreement or warrant, including any duty or responsibility to initiate any proceedings at law or otherwise, or to make any demand upon us. Any holder of a warrant may, without the consent of the related warrant agent or the holder of any other warrant, enforce by appropriate legal action its right to exercise, and receive the securities purchasable upon exercise of, its warrants.

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LEGAL OWNERSHIP OF SECURITIES

        We can issue securities in registered form or in the form of one or more global securities. We describe global securities in greater detail below. We refer to those persons who have securities registered in their own names on the books that we or any applicable trustee maintain for this purpose as the "holders" of those securities. These persons are the legal holders of the securities. We refer to those persons who, indirectly through others, own beneficial interests in securities that are not registered in their own names, as "indirect holders" of those securities. As we discuss below, indirect holders are not legal holders, and investors in securities issued in book-entry form or in street name will be indirect holders.

Book-Entry Holders

        We may issue securities in book-entry form only, as we will specify in the applicable prospectus supplement. This means securities may be represented by one or more global securities registered in the name of a financial institution that holds them as depositary on behalf of other financial institutions that participate in the depositary's book-entry system. These participating institutions, which are referred to as participants, in turn, hold beneficial interests in the securities on behalf of themselves or their customers.

        Only the person in whose name a security is registered is recognized as the holder of that security. Securities issued in global form will be registered in the name of the depositary or its nominee. Consequently, for securities issued in global form, we will recognize only the depositary as the holder of the securities, and we will make all payments on the securities to the depositary. The depositary passes along the payments it receives to its participants, which will in turn pass the payments along to their customers who are the beneficial owners. The depositary and its participants do so under agreements they have made with one another or with their customers; they are not obligated to do so under the terms of the securities.

        As a result, investors in a book-entry security will not own securities directly. Instead, they will own beneficial interests in a global security, through a bank, broker or other financial institution that participates in the depositary's book-entry system or holds an interest through a participant. As long as the securities are issued in global form, investors will be indirect holders, and not holders, of the securities.

Street Name Holders

        We may terminate a global security or issue securities in non-global form. In these cases, investors may choose to hold their securities in their own names or in "street name." Securities held by an investor in street name would be registered in the name of a bank, broker or other financial institution that the investor chooses, and the investor would hold only a beneficial interest in those securities through an account he or she maintains at that institution.

        For securities held in street name, we will recognize only the intermediary banks, brokers and other financial institutions in whose names the securities are registered as the holders of those securities, and we will make all payments on those securities to them. These institutions pass along the payments they receive to their customers who are the beneficial owners, but only because they agree to do so in their customer agreements or because they are legally required to do so. Investors who hold securities in street name will be indirect holders, not holders, of those securities.

Legal Holders

        Our obligations, as well as the obligations of any applicable trustee and of any third parties employed by us or a trustee, run only to the legal holders of the securities. We do not have obligations

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to investors who hold beneficial interests in global securities, in street name or by any other indirect means. This will be the case whether an investor chooses to be an indirect holder of a security or has no choice because we are issuing the securities only in global form.

        For example, once we make a payment or give a notice to the holder, we have no further responsibility for the payment or notice even if that holder is required, under agreements with depositary participants or customers or by law, to pass it along to the indirect holders but does not do so. Similarly, we may want to obtain the approval of the holders to amend an indenture, to relieve us of the consequences of a default or of our obligation to comply with a particular provision of the indenture or for other purposes. In such an event, we would seek approval only from the holders, and not the indirect holders, of the securities. Whether and how the holders contact the indirect holders is up to the holders.

Special Considerations for Indirect Holders

        If you hold securities through a bank, broker or other financial institution, either in book-entry form or in street name, you should check with your own institution to find out:

Global Securities

        A global security is a security held by a depositary that represents one or any other number of individual securities. Generally, all securities represented by the same global securities will have the same terms.

        Each security issued in book-entry form will be represented by a global security that we deposit with and register in the name of a financial institution or its nominee that we select. The financial institution that we select for this purpose is called the depositary. Unless we specify otherwise in the applicable prospectus supplement, DTC will be the depositary for all securities issued in book-entry form.

        A global security may not be transferred to or registered in the name of anyone other than the depositary, its nominee or a successor depositary, unless special termination situations arise. We describe those situations below under "—Special Situations When a Global Security will be Terminated." As a result of these arrangements, the depositary, or its nominee, will be the sole registered owner and holder of all securities represented by a global security, and investors will be permitted to own only beneficial interests in a global security. Beneficial interests must be held by means of an account with a broker, bank or other financial institution that in turn has an account with the depositary or with another institution that does. Thus, an investor whose security is represented by a global security will not be a holder of the security, but only an indirect holder of a beneficial interest in the global security.

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        If the prospectus supplement for a particular security indicates that the security will be issued in global form only, then the security will be represented by a global security at all times unless and until the global security is terminated. If termination occurs, we may issue the securities through another book-entry clearing system or decide that the securities may no longer be held through any book-entry clearing system.

Special Considerations for Global Securities

        As an indirect holder, an investor's rights relating to a global security will be governed by the account rules of the investor's financial institution and of the depositary, as well as general laws relating to securities transfers. We do not recognize an indirect holder as a holder of securities and instead deal only with the depositary that holds the global security.

        If securities are issued only in the form of a global security, an investor should be aware of the following:

Special Situations When a Global Security Will Be Terminated

        In a few special situations described below, the global security will terminate and interests in it will be exchanged for physical certificates representing those interests. After that exchange, the choice of whether to hold securities directly or in street name will be up to the investor. Investors must consult their own banks or brokers to find out how to have their interests in securities transferred to their own name, so that they will be direct holders. We have described the rights of holders and street name investors above.

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        The global security will terminate when the following special situations occur:

        The prospectus supplement may also list additional situations for terminating a global security that would apply only to the particular series of securities covered by the prospectus supplement. When a global security terminates, the depositary, and not we or any applicable trustee, is responsible for deciding the names of the institutions that will be the initial direct holders.

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PLAN OF DISTRIBUTION

        We may sell securities:

        We may directly solicit offers to purchase securities, or agents may be designated to solicit such offers. We will, in the prospectus supplement relating to such offering, name any agent that could be viewed as an underwriter under the Securities Act, and describe any commissions that we must pay. Any such agent will be acting on a best efforts basis for the period of its appointment or, if indicated in the applicable prospectus supplement, on a firm commitment basis. Agents, dealers and underwriters may be customers of, engage in transactions with, or perform services for us in the ordinary course of business.

        The distribution of the securities may be effected from time to time in one or more transactions:

        Each prospectus supplement will describe the method of distribution of the securities and any applicable restrictions.

        The prospectus supplement with respect to the securities of a particular series will describe the terms of the offering of the securities, including the following:

        If any underwriters or agents are utilized in the sale of the securities in respect of which this prospectus is delivered, we will enter into an underwriting agreement or other agreement with them at the time of sale to them, and we will set forth in the prospectus supplement relating to such offering the names of the underwriters or agents and the terms of the related agreement with them.

        If a dealer is utilized in the sale of the securities in respect of which the prospectus is delivered, we will sell such securities to the dealer, as principal. The dealer may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale.

        Remarketing firms, agents, underwriters and dealers may be entitled under agreements which they may enter into with us to indemnification by us against certain civil liabilities, including liabilities under

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the Securities Act, and may be customers of, engage in transactions with or perform services for us in the ordinary course of business.

        If so indicated in the applicable prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by certain institutions to purchase securities from us pursuant to delayed delivery contracts providing for payment and delivery on the date stated in the prospectus supplement. Each contract will be for an amount not less than, and the aggregate amount of securities sold pursuant to such contracts shall not be less nor more than, the respective amounts stated in the prospectus supplement. Institutions with whom the contracts, when authorized, may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but shall in all cases be subject to our approval. Delayed delivery contracts will not be subject to any conditions except that:

        Certain of the underwriters and their associates and affiliates may be customers of, have borrowing relationships with, engage in other transactions with, and/or perform services, including investment banking services, for, us or one or more of our respective affiliates in the ordinary course of business.

        In order to facilitate the offering of the securities, any underwriters may engage in transactions that stabilize, maintain or otherwise affect the price of the securities or any other securities the prices of which may be used to determine payments on such securities. Specifically, any underwriters may overallot in connection with the offering, creating a short position for their own accounts. In addition, to cover overallotments or to stabilize the price of the securities or of any such other securities, the underwriters may bid for, and purchase, the securities or any such other securities in the open market. Finally, in any offering of the securities through a syndicate of underwriters, the underwriting syndicate may reclaim selling concessions allowed to an underwriter or a dealer for distributing the securities in the offering if the syndicate repurchases previously distributed securities in transactions to cover syndicate short positions, in stabilization transactions or otherwise. Any of these activities may stabilize or maintain the market price of the securities above independent market levels. Any such underwriters are not required to engage in these activities and may end any of these activities at any time.

        The securities may be new issues of securities and may have no established trading market. The securities may or may not be listed on a national securities exchange. We can make no assurance as to the liquidity of or the existence of trading markets for any of the securities.


LEGAL MATTERS

        Unless the applicable prospectus supplement indicates otherwise, the validity of the issuance of the securities offered by this prospectus will be passed upon for us by Wilmer Cutler Pickering Hale and Dorr LLP, Boston, Massachusetts.

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EXPERTS

        The consolidated financial statements of Momenta Pharmaceuticals, Inc. appearing in Momenta Pharmaceuticals, Inc.'s Annual Report (Form 10-K) for the year ended December 31, 2008 and the effectiveness of Momenta Pharmaceuticals, Inc.'s internal control over financial reporting as of December 31, 2008, have been audited by Ernst & Young LLP, independent registered public accounting firm, as set forth in their reports thereon included therein, and incorporated herein by reference. Such consolidated financial statements are incorporated herein by reference in reliance upon such report given on the authority of such firm as experts in accounting and auditing.


WHERE YOU CAN FIND MORE INFORMATION

        We file reports, proxy statements and other documents with the SEC. You may read and copy any document we file with the SEC at the SEC's Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the public reference room.

        The SEC also maintains an Internet site that contains reports, proxy and information statements, and other information regarding registrants, like us, that file electronically with the SEC. The address of the SEC's Internet site is www.sec.gov. Our website is www.momentapharma.com. The information set forth on our website is not part of this prospectus.

        Our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and other filings with the SEC are available, free of charge, through our website, shortly after those reports or filings are electronically filed with or furnished to the SEC. Information on our website or any other website is not incorporated by reference into this prospectus and does not constitute a part of this prospectus.

        This prospectus is part of a registration statement we filed with the SEC relating to the securities we may offer. As permitted by SEC rules, this prospectus does not contain all of the information we have included in the registration statement and the accompanying exhibits and schedules we filed with the SEC. You may refer to the registration statement, exhibits and schedules for more information about us and the securities. The registration statement, exhibits and schedules are available at the SEC's Public Reference Room or through its website.


INCORPORATION OF DOCUMENTS BY REFERENCE

        We are "incorporating by reference" in this prospectus some of the documents we file with the SEC. This means that we can disclose important information to you by referring you to those documents. The information in the documents incorporated by reference is considered to be part of this prospectus. Statements contained in documents that we file with the SEC and that are incorporated by reference in this prospectus will automatically update and supersede information contained in this prospectus, including information in previously filed documents or reports that have been incorporated by reference in this prospectus, to the extent the new information differs from or is inconsistent with the old information.

        We have filed or may file the following documents with the SEC. These documents are incorporated herein by reference as of their respective dates of filing (other than, in each case, documents or information deemed to have been furnished and not filed in accordance with SEC rules):

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        You may request, orally or in writing, a copy of these documents, which will be provided to you at no cost, by contacting Momenta Pharmaceuticals, Inc., 675 West Kendall Street, Cambridge, Massachusetts 02142, Attention: Bruce A. Leicher, Corporate Secretary, telephone: (617) 491-9700.

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PART II

INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14.    Other Expenses of Issuance and Distribution.

        The following table sets forth the various expenses to be incurred in connection with the registration of the securities being registered hereby, all of which will be borne by Momenta Pharmaceuticals, Inc. All amounts shown are estimates except the SEC registration fee.

SEC registration fee

  $ 4,166  

Transfer agent's, trustee's and depository's fees and expenses

    10,000  

Printing and engraving expenses

    25,000  

Legal fees and expenses

    50,000  

Accounting fees and expenses

    25,000  

Miscellaneous

    3,834  
       

Total expenses

  $ 120,000  
       

Item 15.    Indemnification of Directors and Officers.

        Section 102 of the General Corporation Law of the State of Delaware permits a corporation to eliminate the personal liability of directors of a corporation to the corporation or its stockholders for monetary damages for a breach of fiduciary duty as a director, except where the director breached his duty of loyalty, failed to act in good faith, engaged in intentional misconduct or knowingly violated a law, authorized the payment of a dividend or approved a stock repurchase in violation of Delaware corporate law or obtained an improper personal benefit. Our certificate of incorporation provides that no director of the registrant shall be personally liable to us or our stockholders for monetary damages for any breach of fiduciary duty as a director, notwithstanding any provision of law imposing such liability, except to the extent that the General Corporation Law of the State of Delaware prohibits the elimination or limitation of liability of directors for breaches of fiduciary duty.

        Section 145 of the General Corporation Law of the State of Delaware provides that a corporation has the power to indemnify a director, officer, employee or agent of the corporation and certain other persons serving at the request of the corporation in related capacities against expenses (including attorneys' fees), judgments, fines and amounts paid in settlements actually and reasonably incurred by the person in connection with an action, suit or proceeding to which he is or is threatened to be made a party by reason of such position, if such person acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation, and, in any criminal action or proceeding, had no reasonable cause to believe his conduct was unlawful, except that, in the case of actions brought by or in the right of the corporation, no indemnification shall be made with respect to any claim, issue or matter as to which such person shall have been adjudged to be liable to the corporation unless and only to the extent that the Court of Chancery or other adjudicating court determines that, despite the adjudication of liability but in view of all of the circumstances of the case, such person is fairly and reasonably entitled to indemnity for such expenses which the Court of Chancery or such other court shall deem proper.

        Our certificate of incorporation provides that we will indemnify each person who was or is a party or threatened to be made a party to any threatened, pending or completed action, suit or proceeding (other than an action by or in the right of the corporation) by reason of the fact that he or she is or was, or has agreed to become, a director or officer of the registrant, or is or was serving, or has agreed to serve, at our request as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or other enterprise (all such persons being referred to as an "Indemnitee"), or by reason of any action alleged to have been taken or omitted in

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such capacity, against all expenses (including attorneys' fees), judgments, fines and amounts paid in settlement actually and reasonably incurred in connection with such action, suit or proceeding and any appeal therefrom, if such Indemnitee acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, the corporation's best interests, and, with respect to any criminal action or proceeding, he or she had no reasonable cause to believe his or her conduct was unlawful. Our certificate of incorporation provides that we will indemnify any Indemnitee who was or is a party to an action or suit by or in the right of the corporation to procure a judgment in its favor by reason of the fact that the Indemnitee is or was, or has agreed to become, a director or officer of Momenta, or is or was serving, or has agreed to serve, at our request as a director, officer, partner, employee or trustee of, or in a similar capacity with, another corporation, partnership, joint venture, trust or other enterprise, or by reason of any action alleged to have been taken or omitted in such capacity, against all expenses (including attorneys' fees) and, to the extent permitted by law, amounts paid in settlement actually and reasonably incurred in connection with such action, suit or proceeding, and any appeal therefrom, if the Indemnitee acted in good faith and in a manner he or she reasonably believed to be in, or not opposed to, the best interests of the corporation, except that no indemnification shall be made with respect to any claim, issue or matter as to which such person shall have been adjudged to be liable to us, unless a court determines that, despite such adjudication but in view of all of the circumstances, he or she is entitled to indemnification of such expenses. Notwithstanding the foregoing, to the extent that any Indemnitee has been successful, on the merits or otherwise, he or she will be indemnified by us against all expenses (including attorneys' fees) actually and reasonably incurred in connection therewith. Expenses must be advanced to an Indemnitee under certain circumstances.

        The indemnification provisions contained in our certificate of incorporation are not exclusive of any other rights to which a person may be entitled by law, agreement, vote of stockholders or disinterested directors or otherwise.

        In addition, we maintain insurance on behalf of its directors and executive officers insuring them against certain liability asserted against them in their capacities as directors or officers or arising out of such status.

Item 16.    Exhibits.

Exhibit
Number
  Description
  1.1 * Form of underwriting agreement.
        
  3.1   Third Amended and Restated Certificate of Incorporation (filed as Exhibit 3.3 to the Registrant's Registration Statement on Form S-1 filed on March 11, 2004 (File No. 333-113522) and incorporated in this document by reference).
        
  3.2   Certificate of Designations of Series A Junior Participating Preferred Stock, as filed with the Secretary of State of the State of Delaware on November 8, 2005 (filed as Exhibit 3.1 to the Registrant's Current Report on Form 8-K filed on November 8, 2005 and incorporated in this document by reference).
        
  3.3   Amended and Restated By-laws (filed as Exhibit 3.2 to the Registrant's Registration Statement on Form S-1 filed on March 11, 2004 (File No. 333-113522) and incorporated in this document by reference).
        
  4.1   Form of senior indenture.
        
  4.2   Form of subordinated indenture.
        
  4.3 * Form of any senior note with respect to each particular series of senior debt securities issued hereunder.
 
   

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Exhibit
Number
  Description
  4.4 * Form of any subordinated note with respect to each particular series of subordinated debt securities issued hereunder.
        
  4.5 * Form of Warrant Agreement.
        
  4.8 * Form of Certificate of Designation with respect to any preferred stock certificate and related form of preferred stock certificate.
        
  5.1   Opinion of Wilmer Cutler Pickering Hale and Dorr LLP.
        
  8.1 * Opinion of tax counsel on certain U.S. federal income tax matters.
        
  12.1   Schedule of ratio of earnings to fixed charges.
        
  23.1   Consent of Independent Registered Public Accounting Firm.
        
  23.2   Consent of Wilmer Cutler Pickering Hale and Dorr LLP (included in Exhibit 5.1).
        
  24.1   Power of Attorney (see page II-7).
        
  25.1 * Statement of Eligibility on Form T-1 under the Trust Indenture Act of 1939, as amended, of the Trustee.

*
To be filed by amendment or by a Current Report on Form 8-K prior to the issuance of the applicable securities and incorporated herein by reference.

Item 17.    Undertakings.

        Provided, however, That: paragraphs (a)(1)(i), (a)(1)(ii) and (a)(1)(iii) above do not apply if the information required to be included in a post-effective amendment by those paragraphs is contained in reports filed with or furnished to the Commission by the registrant pursuant to Section 13 or Section 15(d) of the Securities Exchange Act of 1934 that are incorporated by reference in the registration statement, or is contained in a form of prospectus filed pursuant to Rule 424(b) that is part of the registration statement.

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        The undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

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SIGNATURES

        Pursuant to the requirements of the Securities Act of 1933, the registrant certifies that it has reasonable grounds to believe that it meets all of the requirements for filing on Form S-3 and has duly caused this registration statement to be signed on its behalf by the undersigned, thereunto duly authorized, in the City of Cambridge, Commonwealth of Massachusetts, on December 9, 2009.

    MOMENTA PHARMACEUTICALS, INC.

 

 

By:

 

/s/ CRAIG A. WHEELER

Craig A. Wheeler
President and Chief Executive Officer

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SIGNATURES AND POWER OF ATTORNEY

        We, the undersigned officers and directors of Momenta Pharmaceuticals, Inc., hereby severally constitute and appoint Craig A. Wheeler and Richard P. Shea, and each of them singly, our true and lawful attorneys-in-fact and agents, with full power to them, to sign for us and in our names in the capacities indicated below, any and all pre-effective and post-effective amendments to the registration statement on Form S-3 filed herewith, and any subsequent registration statement for the same offering that may be filed under Rule 462(b), and generally to do all such things in our names and on our behalf in our capacities as officers and directors to enable Momenta Pharmaceuticals, Inc. to comply with the provisions of the Securities Act of 1933, as amended, and all requirements of the Securities and Exchange Commission, hereby ratifying and confirming our signatures as they may be signed by our said attorneys-in-fact and agents, or any of them, to said amendments or to any subsequent registration statement for the same offering that may be filed pursuant to Rule 462(b).

        Pursuant to the requirements of the Securities Act of 1933, as amended, this registration statement has been signed by the following persons in the capacities and on the dates indicated.

Signature
 
Title
 
Date

 

 

 

 

 
/s/ CRAIG A. WHEELER

Craig A. Wheeler
  President and Chief Executive Officer and Director
(Principal Executive Officer)
  December 9, 2009

/s/ RICHARD P. SHEA

Richard P. Shea

 

Senior Vice President and Chief Financial Officer
(Principal Financial and Accounting Officer)

 

December 9, 2009

/s/ JAMES SULAT

James Sulat

 

Director and Chairman of the Board

 

December 9, 2009

/s/ JOHN K. CLARKE

John K. Clarke

 

Director

 

December 9, 2009

/s/ ALAN L. CRANE

Alan L. Crane

 

Director

 

December 9, 2009

/s/ BRUCE DOWNEY

Bruce Downey

 

Director

 

December 9, 2009

/s/ MARSHA H. FANUCCI

Marsha H. Fanucci

 

Director

 

December 9, 2009

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Signature
 
Title
 
Date

 

 

 

 

 
/s/ PETER BARTON HUTT, LLB, LLM

Peter Barton Hutt, LLB, LLM
  Director   December 9, 2009

  

Ram Sasisekharan, Ph.D.

 

Director

 

December 9, 2009

/s/ BENNETT M. SHAPIRO, M.D.

Bennett M. Shapiro, M.D.

 

Director

 

December 9, 2009

/s/ ELIZABETH STONER, M.D.

Elizabeth Stoner, M.D.

 

Director

 

December 9, 2009

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EXHIBIT INDEX

Exhibit
Number
  Description
  1.1 * Form of underwriting agreement.
        
  3.1   Third Amended and Restated Certificate of Incorporation (filed as Exhibit 3.3 to the Registrant's Registration Statement on Form S-1 filed on March 11, 2004 (File No. 333-113522) and incorporated in this document by reference).
        
  3.2   Certificate of Designations of Series A Junior Participating Preferred Stock, as filed with the Secretary of State of the State of Delaware on November 8, 2005 (filed as Exhibit 3.1 to the Registrant's Current Report on Form 8-K filed on November 8, 2005 and incorporated in this document by reference).
        
  3.3   Amended and Restated By-laws (filed as Exhibit 3.2 to the Registrant's Registration Statement on Form S-1 filed on March 11, 2004 (File No. 333-113522) and incorporated in this document by reference).
        
  4.1   Form of senior indenture.
        
  4.2   Form of subordinated indenture.
        
  4.3 * Form of any senior note with respect to each particular series of senior debt securities issued hereunder.
        
  4.4 * Form of any subordinated note with respect to each particular series of subordinated debt securities issued hereunder.
        
  4.5 * Form of Warrant Agreement.
        
  4.8 * Form of Certificate of Designation with respect to any preferred stock certificate and related form of preferred stock certificate.
        
  5.1   Opinion of Wilmer Cutler Pickering Hale and Dorr LLP.
        
  8.1 * Opinion of tax counsel on certain U.S. federal income tax matters.
        
  12.1   Schedule of ratio of earnings to fixed charges.
        
  23.1   Consent of Independent Registered Public Accounting Firm.
        
  23.2   Consent of Wilmer Cutler Pickering Hale and Dorr LLP (included in Exhibit 5.1).
        
  24.1   Power of Attorney (see page II-7).
        
  25.1 * Statement of Eligibility on Form T-1 under the Trust Indenture Act of 1939, as amended, of the Trustee.

*
To be filed by amendment or by a Current Report on Form 8-K prior to the issuance of the applicable securities and incorporated herein by reference.