Attached files

file filename
EX-21 - EX-21 - MOMENTA PHARMACEUTICALS INCa2223226zex-21.htm
EX-31.1 - EX-31.1 - MOMENTA PHARMACEUTICALS INCa2223226zex-31_1.htm
EX-23.1 - EX-23.1 - MOMENTA PHARMACEUTICALS INCa2223226zex-23_1.htm
EX-31.2 - EX-31.2 - MOMENTA PHARMACEUTICALS INCa2223226zex-31_2.htm
EXCEL - IDEA: XBRL DOCUMENT - MOMENTA PHARMACEUTICALS INCFinancial_Report.xls
10-K - 10-K - MOMENTA PHARMACEUTICALS INCa2223226z10-k.htm

QuickLinks -- Click here to rapidly navigate through this document


Exhibit 32.1

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,

AS ADOPTED PURSUANT TO

SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        In connection with the Annual Report on Form 10-K of Momenta Pharmaceuticals, Inc. (the "Company") for the period ended December 31, 2014 as filed with the Securities and Exchange Commission on the date hereof (the "Report"), the undersigned, Craig A. Wheeler, President and Chief Executive Officer of the Company, and Richard P. Shea, Senior Vice President and Chief Financial Officer of the Company, each hereby certifies, pursuant to 18 U.S.C. Section 1350, that:

    (1)
    The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

    (2)
    The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Dated: February 27, 2015   /s/ CRAIG A. WHEELER

Craig A. Wheeler
President and Chief Executive Officer

Dated: February 27, 2015

 

/s/ RICHARD P. SHEA

Richard P. Shea
Senior Vice President and Chief Financial Officer



QuickLinks

CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002