MNTA Momenta Pharmaceuticals Inc

FORM 4 [X] 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                                                                                   
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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 * Cieplinska Agnieszka	2. Issuer Name and Ticker or Trading Symbol MOMENTA PHARMACEUTICALS INC [ MNTA ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director                    _____ 10% Owner __X__ Officer (give title below)    _____ Other (specify below) Chief Accounting Officer (PAO)
(Last)          (First)          (Middle) C/O MOMENTA PHARMACEUTICALS, INC., 301 BINNEY STREET	3. Date of Earliest Transaction (MM/DD/YYYY) 10/1/2020
(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	10/1/2020		D		8136 (1)	D	(2)	0	D

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	(3)	10/1/2020		D			9450	(3)	(3)	Common Stock	9450	(3)	0	D
Restricted Stock Units	(3)	10/1/2020		D			8193	(3)	(3)	Common Stock	8193	(3)	0	D
Stock Options (Right to Buy)	$13.85	10/1/2020		D			22845	(4)	4/12/2029	Common Stock	22845	(4)	0	D
Stock Option (Right to Buy)	$31.87	10/1/2020		D			3641	(4)	2/7/2030	Common Stock	3641	(4)	0	D
Stock Option (Right to Buy)	$13.85	10/1/2020		D			2155	(4)	4/12/2029	Common Stock	2155	(4)	0	D
Stock Option (Right to Buy)	$31.87	10/1/2020		D			12672	(4)	2/7/2030	Common Stock	12672	(4)	0	D

Explanation of Responses:
(1)	Includes 425 shares and 137 shares acquired under the Issuer's employee stock purchase plan respectively on July 31, 2020 and September 28, 2020.
(2)	Reflects disposition of Issuer common stock in connection with the consummation of the transactions contemplated by that certain Agreement and Plan of Merger, dated as of August 19, 2020 (the "Merger Agreement"), by and among Johnson & Johnson, Vigor Sub, Inc. ("Merger Sub") and the Issuer, including the completion of a tender offer to purchase all of the outstanding shares of Issuer common stock at a price of $52.50 per share in cash, without interest, less any required withholding taxes (the "Offer Price"), and the consummation of the merger (the "Merger") between the Issuer and Merger Sub on October 1, 2020. Pursuant to the Merger Agreement, as of the effective time of the Merger (the "Effective Time"), each outstanding share of Issuer common stock was cancelled in exchange for the right to receive an amount equal to the Offer Price.
(3)	Reflects disposition of Issuer restricted stock units in accordance with the Merger Agreement, pursuant to which, effective immediately prior to the Effective Time, each Issuer restricted stock unit held by the Reporting Person became vested in full and, as of the Effective Time, was cancelled and converted into the right to receive an amount in cash (without interest) equal to the product obtained by multiplying (x) the aggregate number of shares of Issuer common stock underlying such Issuer restricted stock unit immediately prior to the Effective Time by (y) the Offer Price.
(4)	Reflects disposition of options to acquire shares of Issuer common stock (each, an "Issuer Option") in accordance with the Merger Agreement, pursuant to which, effective immediately prior to the Effective Time, each Issuer Option held by the Reporting Person became vested in full and, as of the Effective Time, was cancelled and converted into the right to receive an amount in cash (without interest) equal to the product obtained by multiplying (x) the aggregate number of shares of Issuer common stock underlying such Issuer Option immediately prior to the Effective Time by (y) the amount, if any, by which the Offer Price exceeds the per share exercise price of such Issuer Option.

Reporting Owners
Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Cieplinska Agnieszka C/O MOMENTA PHARMACEUTICALS, INC. 301 BINNEY STREET CAMBRIDGE, MA 02142			Chief Accounting Officer (PAO)

Signatures
/s/ R. Mark Chamberlin as attorney in fact		10/1/2020
**Signature of Reporting Person		Date