Statement of Changes in Beneficial Ownership (4)

FORM 4

[ ] Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

OMB APPROVAL

OMB Number:

3235-0287

Estimated average burden
hours per response...

0.5

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

1. Name and Address of Reporting Person * WHEELER CRAIG A	2. Issuer Name and Ticker or Trading Symbol MOMENTA PHARMACEUTICALS INC [ MNTA ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director                    _____ 10% Owner __X__ Officer (give title below)    _____ Other (specify below) President & CEO
(Last)          (First)          (Middle) C/O MOMENTA PHARMACEUTICALS, INC., 301 BINNEY STREET	3. Date of Earliest Transaction (MM/DD/YYYY) 8/12/2020
(Street) CAMBRIDGE, MA 02142 (City)        (State)        (Zip)	4. If Amendment, Date Original Filed (MM/DD/YYYY)	6. Individual or Joint/Group Filing (Check Applicable Line) _X _ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security (Instr. 3)	2. Trans. Date	2A. Deemed Execution Date, if any	3. Trans. Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	8/12/2020		M(1)		6171	A	(2)	18090	D
Common Stock	8/13/2020		S(3)		2777	D	$28.55 (4)	15313	D
Common Stock								36725	I	Craig A Wheeler 2016 Annuity Trust
Common Stock								48263	I	Craig A Wheeler 2018 Annuity Trust
Common Stock								573022	I	Craig Wheeler Revocable Trust

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivate Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Trans. Date	3A. Deemed Execution Date, if any	4. Trans. Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Restricted Stock Units	(2)	8/12/2020		M (1)			6171	(5)	(5)	Common Stock	6171	$0	37032	D

Explanation of Responses:
(1)	Shares received pursuant to settlement of Restricted Stock Units that were granted on February 12, 2018.
(2)	Restricted Stock Units convert into common stock on a one-for-one basis.
(3)	This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on November 16, 2018.
(4)	This transaction was executed in multiple trades at prices ranging from $28.18 to $29.04. 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.
(5)	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.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
WHEELER CRAIG A C/O MOMENTA PHARMACEUTICALS, INC. 301 BINNEY STREET CAMBRIDGE, MA 02142	X		President & CEO

Signatures
/s/ R. Mark Chamberlin as attorney in fact		8/13/2020
**Signature of Reporting Person		Date