X0306 4 2020-02-07 0 0001235010 MOMENTA PHARMACEUTICALS INC MNTA 0001229450 WHEELER CRAIG A C/O MOMENTA PHARMACEUTICALS, INC. 301 BINNEY STREET CAMBRIDGE MA 02142 1 1 0 0 President & CEO Common Stock 2020-02-07 4 M 0 4890 13.26 A 17567 D Common Stock 2020-02-07 4 S 0 4890 32.04 D 12677 D Common Stock 2020-02-07 4 M 0 5781 A 18458 D Common Stock 2020-02-10 4 S 0 2601 31.43 D 15857 D Common Stock 36725 I Craig A Wheeler 2016 Annuity Trust Common Stock 48263 I Craig A Wheeler 2018 Annuity Trust Common Stock 419934 I Craig Wheeler Revocable Trust Restriced Stock Units 2020-02-07 4 A 0 100000 0 A Common Stock 100000 100000 D Stock Option (Right to Buy) 31.87 2020-02-07 4 A 0 200000 0 A 2030-02-07 Common Stock 200000 200000 D Stock Option (Right to Buy) 13.26 2020-02-07 4 M 0 2423 0 D 2015-02-22 2021-02-22 Common Stock 2423 4124 D Stock Option (Right to Buy) 13.26 2020-02-07 4 M 0 2467 0 D 2012-08-22 2021-02-22 Common Stock 2467 57653 D Restricted Stock Units 2020-02-07 4 M 0 5781 0 D Common Stock 5781 23126 D This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on December 14, 2018. This transaction was executed in multiple trades at prices ranging from $32.00 to $32.13. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote. Shares received pursuant to settlement of Restricted Stock Units that were granted on February 7, 2017. Restricted Stock Units convert into common stock on a one-for-one basis. This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 7, 2017. This transaction was executed in multiple trades at prices ranging from $30.91 to $31.72. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide upon request to the SEC staff, the issuer or a security holder of the issuer full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote. Each Restricted Stock Unit represents a contingent right to receive one share of MNTA common stock. Represents restricted stock granted by the issuer pursuant to the issuer's 2013 Incentive Award Plan, as amended and restated. Subject to the officer's continued employment with the company, the restricted stock units will vest with respect to 25% of the shares on the first anniversary of the grant date, and the remainder will vest in equal quarterly installments over the subsequent three years. Represents options granted by the issuer pursuant to the issuer's 2013 Incentive Award Plan, as amended and restated. Subject to certain criteria, the stock options will vest with respect to 25% of the shares on the first anniversary of the grant date, and the remainder will vest in equal quarterly installments over the subsequent three years. /s/ R. Mark Chamberlin as attorney in fact 2020-02-11