SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person* Levy Noah G. (Last) (First) (Middle) 60 EAST 42ND ST., 9TH FLOOR (Street) NEW YORK NY 10165 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 09/18/2019	3. Issuer Name and Ticker or Trading Symbol MERRIMACK PHARMACEUTICALS INC [ MACK ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) X Director 10% Owner Officer (give title below) X Other (specify below) See Remarks	5. 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 Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	677,546	I	See footnote(1)
Common Stock	495,620	I	See footnote(2)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* Levy Noah G. (Last) (First) (Middle) 60 EAST 42ND ST., 9TH FLOOR (Street) NEW YORK NY 10165 (City) (State) (Zip)

1. Name and Address of Reporting Person* Newtyn Management, LLC (Last) (First) (Middle) 60 EAST 42ND ST., 9TH FLOOR (Street) NEW YORK NY 10165 (City) (State) (Zip)

1. Name and Address of Reporting Person* NEWTYN PARTNERS, LP (Last) (First) (Middle) 60 EAST 42ND ST., 9TH FLOOR (Street) NEW YORK NY 10165 (City) (State) (Zip)

1. Name and Address of Reporting Person* NEWTYN TE PARTNERS, LP (Last) (First) (Middle) 60 EAST 42ND ST., 9TH FLOOR (Street) NEW YORK NY 10165 (City) (State) (Zip)

1. Name and Address of Reporting Person* Newtyn Capital Partners, LP (Last) (First) (Middle) 60 EAST 42ND ST., 9TH FLOOR (Street) NEW YORK NY 10165 (City) (State) (Zip)

1. Name and Address of Reporting Person* Ledo Capital, LLC (Last) (First) (Middle) 60 EAST 42ND ST., 9TH FLOOR (Street) NEW YORK NY 10165 (City) (State) (Zip)

Explanation of Responses:

1. The shares are directly held by NP. The general partner of the Funds is NCP. The general partner of NCP is Ledo. The investment manager to the Funds is Newtyn Management. The managing member of Newtyn Management and Ledo and the portfolio manager to the Funds is Mr. Levy. Each of Newtyn Management, Ledo, NCP and Mr. Levy disclaims beneficial ownership of the shares except to the extent of its or his pecuniary interest therein, if any, and this report shall not be deemed an admission that it or he is the beneficial owner of such shares.

2. The shares are directly held Newtyn TE. The general partner of the Funds is NCP. The general partner of NCP is Ledo. The investment manager to the Funds is Newtyn Management. The managing member of Newtyn Management and Ledo and the portfolio manager to the Funds is Mr. Levy. Each of Newtyn Management, Ledo, NCP and Mr. Levy disclaims beneficial ownership of the shares except to the extent of its or his pecuniary interest therein, if any, and this report shall not be deemed an admission that it or he is the beneficial owner of such shares.

Remarks:

As a result of an agreement among the persons listed below to vote their respective shares of Common Stock jointly, such persons have formed a "group" under Section 13(d)(1) of the Exchange Act. In addition to Mr. Levy, Newtyn Management, LLC ("Newtyn Management"), Newtyn Partners, LP ("NP"), Newtyn TE Partners, LP ("Newtyn TE" and together with NP, the "Funds"), Newtyn Capital Partners, LP ("NCP") and Ledo Capital, LLC ("Ledo") (collectively, the "Newtyn Parties"), the members of this group are Eric D. Andersen, Western Standard, LLC, Western Standard Partners, LP and Western Standard Partners QP, LP (the "Western Standard Parties" and collectively with the Newtyn Parties, the "13D Group"). As a member of the 13D Group, each Newtyn Party would be deemed to beneficially own the aggregate amount of the Common Stock that each of the 13D Group members beneficially owns, in which case it or he would be deemed to beneficially own 2,016,079 shares of Common Stock. However, none of the Newtyn Parties have the ability to direct the acquisition or disposition or, except through the Cooperation Agreement, voting of the securities held by Western Standard Parties, and none of the Western Standard Parties have the ability to direct the acquisition or disposition or, except through the Cooperation Agreement, voting of the securities held by the Newtyn Parties. As members of the 13D Group, the combined holdings of the Newtyn Parties and the Western Standard Parties would result in each Newtyn Party having voting power equivalent to a combined beneficial ownership of 15.1% of the Issuer's outstanding Common Stock for voting purposes. Each Newtyn Party disclaims beneficial ownership of the shares beneficially owned by the 13D Group except to the extent of its or his pecuniary interest therein, if any, and this report shall not be deemed an admission that it or he is the beneficial owner of such shares.

	/s/ Noah G. Levy	09/27/2019
	Newtyn Management, LLC; /s/ Noah G. Levy, Managing Member	09/27/2019
	Newtyn Partners, LP; By: Newtyn Management, LLC, Investment Manager; /s/ Noah G. Levy, Managing Member	09/27/2019
	Newtyn TE Partners, LP; By: Newtyn Management, LLC, Investment Manager; /s/ Noah G. Levy, Managing Member	09/27/2019
	Newtyn Capital Partners, LP; By: Ledo Capital, LLC, General Partner; /s/ Noah G. Levy, Managing Member	09/27/2019
	Ledo Capital, LLC; /s/ Noah G. Levy, Managing Member	09/27/2019
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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