SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* MORGENTHALER VENTURE PARTNERS IX LP (Last) (First) (Middle) 3200 ALPINE ROAD (Street) PORTOLA VALLEY CA 94028 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Ra Pharmaceuticals, Inc. [ RARX ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 10/31/2016
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X 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. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction 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	10/31/2016		X		63,019	A	$0.07(2)	80,161	D(1)
Common Stock	10/31/2016		S(2)		340	D	$13(2)	79,821	D(1)
Common Stock	10/31/2016		C		1,392,130	A	(3)	1,471,951	D(1)
Common Stock	10/31/2016		C		523,438	A	(4)	1,995,389	D(1)
Common Stock	10/31/2016		C		486,919	A	(5)	2,482,308	D(1)
Common Stock	10/31/2016		P		263,538	A	$13	2,745,846	D(1)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction 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 (Month/Day/Year)		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: 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
Warrants to Purchase Common Stock	$0.07(2)	10/31/2016		X			63,019	(2)	04/01/2022	Common Stock	63,019	$0	0	D(1)
Series A Preferred Stock	(3)	10/31/2016		C			9,744,916	(3)	(3)	Common Stock	1,392,130	(3)	0	D(1)
Series B-1 Preferred Stock	(4)	10/31/2016		C			3,664,071	(4)	(4)	Common Stock	523,438	(4)	0	D(1)
Series B-2 Preferred Stock	(5)	10/31/2016		C			3,408,439	(5)	(5)	Common Stock	486,919	(5)	0	D(1)

1. Name and Address of Reporting Person* MORGENTHALER VENTURE PARTNERS IX LP (Last) (First) (Middle) 3200 ALPINE ROAD (Street) PORTOLA VALLEY CA 94028 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Morgenthaler Management Partners IX, LLC (Last) (First) (Middle) 3200 ALPINE ROAD (Street) PORTOLA VALLEY CA 94028 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. The securities are held by Morgenthaler Venture Partners IX, L.P. ("MVP IX"). The general partner of MVP IX is Morgenthaler Management Partners IX, LLC ("MMP IX"). MMP IX may be deemed to indirectly beneficially own the securities directly held by MVP IX. MMP IX disclaims beneficial ownership of the securities held by MVP IX except to the extent of its pecuniary interest therein.

2. The Warrants were automatically exercised immediately prior to the closing of the Issuer's initial public offering for such number of shares issuable pursuant to a cashless net exercise provision, resulting in the Issuer withholding 340 of the warrant shares to pay the aggregate exercise price, using the offering price in the Issuer's initial public offering of $13.00, and issuing to the reporting person the remaining 62,679 shares.

3. Each share of the Series A Preferred Stock converted into Common Stock on a 1-for-7 basis automatically and without additional consideration upon the closing of the Issuer's initial public offering, and had no expiration date.

4. Each share of the Series B-1 Preferred Stock converted into Common Stock on a 1-for-7 basis automatically and without additional consideration upon the closing of the Issuer's initial public offering, and had no expiration date.

5. Each share of the Series B-2 Preferred Stock converted into Common Stock on a 1-for-7 basis automatically and without additional consideration upon the closing of the Issuer's initial public offering, and had no expiration date.

	MORGENTHALER VENTURE PARTNERS IX, L.P.By: Morgenthaler Management Partners IX, LLC, its General Partner, By: /s/ Jason Lettmann Name: Jason Lettmann, Its: Member	10/31/2016
	MORGENTHALER MANAGEMENT PARTNERS IX, LLC, By: /s/ Jason Lettmann, Its: Member	10/31/2016
	** Signature of Reporting Person	Date
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