Momenta Pharmaceuticals, Inc. (MNTA)

[DewDiligence]

MNTA Major Shareholders

[Updated for BlackRock 13G filing today.]


The table below shows all shareholders who filed their MNTA holdings
on SEC Form 13G during the past 12 months; the holdings are updated
quarterly from filings on Form 13F-HR and are accurate as of 12/31/12
(except BlackRock, which is as of 2/28/13).

The percentages in the table are based on 54.3M diluted shares (#msg-76922372)
and do not concur with the percentages on Form 13G, which uses a different formula.

 
                            Shares    Stake 
 BlackRock Fund Advsrs     5,248,262   9.7% 
 Novartis                  4,708,679   8.7% 
 Visium Asset Mgmt         4,000,000   7.4% 
 T Rowe Price              3,991,277   7.3% 
 Scopia Mgmt               3,799,786   7.0% 
 Fidelity (FMR)            3,146,221   5.8% 
 Vanguard                  2,675,796   4.9%