Initial Statement of Beneficial Ownership (3)

FORM 3	UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES	OMB APPROVAL OMB Number: 3235-0104 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 ^*

Andersen Eric

2. Date of Event Requiring Statement (MM/DD/YYYY) 9/18/2019

3. Issuer Name and Ticker or Trading Symbol

MERRIMACK PHARMACEUTICALS INC [MACK]

(Last) (First) (Middle)

5900 WILSHIRE BOULEVARD, SUITE 650

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

(Street)

LOS ANGELES, CA 90036

(City) (State) (Zip)

5. If Amendment, Date Original Filed(MM/DD/YYYY)

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	666327	I	See footnote ⁽¹⁾
Common Stock	176586	I	See footnote ⁽²⁾

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

Explanation of Responses:
(1)	The shares are directly held by WSP. The general partner of the Funds is Western Standard. The managing member of Western Standard and the portfolio manager to the Funds is Mr. Andersen. Each of Western Standard and Mr. Andersen 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 by WSP QP. The general partner of the Funds is Western Standard. The managing member of Western Standard and the portfolio manager to the Funds is Mr. Andersen. Each of Western Standard and Mr. Andersen 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. Andersen, Western Standard, LLC ("Western Standard"), Western Standard Partners, LP ("WSP") and Western Standard Partners QP, LP ("WSP QP" and together with WSP, the "Funds") (collectively, the "Western Standard Parties"), the members of this group are Noah G. Levy, Newtyn Management, LLC, Newtyn Partners, Newtyn TE Partners, LP, Newtyn Capital Partners, LP, and Ledo Capital, LLC (collectively, the "Newtyn Parties" and collectively with the Western Standard Parties, the "13D Group").
As a member of the 13D Group, each Western Standard 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 Western Standard Parties have the ability to direct the acquisition or disposition or, except through the Cooperation Agreement, voting of the securities held by Newtyn Parties, and 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 the Western Standard Parties. As members of the 13D Group, the combined holdings of the Western Standard Parties and the Newtyn Parties would result in each Western Standard Party having voting power equivalent to a combined beneficial ownership of 15.1% of the Issuer's outstanding Common Stock for voting purposes. Each Western Standard 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.

Reporting Owners
Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
Andersen Eric 5900 WILSHIRE BOULEVARD, SUITE 650 LOS ANGELES, CA 90036	X			See Remarks
Western Standard LLC 5900 WILSHIRE BOULEVARD, SUITE 650 LOS ANGELES, CA 90036				See Remarks
WESTERN STANDARD PARTNERS LP 5900 WILSHIRE BOULEVARD, SUITE 650 LOS ANGELES, CA 90036				See Remarks
Western Standard Partners QP, L.P. 5900 WILSHIRE BOULEVARD, SUITE 650 LOS ANGELES, CA 90036				See Remarks

Signatures
/s/ Eric D. Andersen		9/27/2019
^**Signature of Reporting Person		Date
Western Standard, LLC; /s/ Eric D. Andersen, Managing Member		9/27/2019
^**Signature of Reporting Person		Date
Western Standard Partners, LP; By: Western Standard, LLC, General Partner; /s/ Eric D. Andersen, Managing Member		9/27/2019
^**Signature of Reporting Person		Date
Western Standard Partners QP, LP; By: Western Standard, LLC, General Partner; /s/ Eric D. Andersen, Managing Member		9/27/2019
^**Signature of Reporting Person		Date