# EDGAR Filing Document

**Accession Number:** 0001450414
**File Stem:** 0000950170-23-009171
**Filing Date:** 2023-3
**Character Count:** 13588
**Document Hash:** 2ec3a6a310e5a69345003744e71a6cb1
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0000950170-23-009171.hdr.sgml**: 20230322

**ACCESSION NUMBER**: 0000950170-23-009171

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 1

**CONFORMED PERIOD OF REPORT**: 20230321

**FILED AS OF DATE**: 20230322

**DATE AS OF CHANGE**: 20230322

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Western Standard LLC
- **CENTRAL INDEX KEY:** 0001517666
- **STATE OF INCORPORATION:** CA

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-35409
- **FILM NUMBER:** 23752981

**BUSINESS ADDRESS:**
- **STREET 1:** 5900 WILSHIRE BLVD
- **STREET 2:** SUITE 650
- **CITY:** LOS ANGELES
- **STATE:** CA
- **ZIP:** 90036
- **BUSINESS PHONE:** 3107465639

**MAIL ADDRESS:**
- **STREET 1:** 5900 WILSHIRE BLVD
- **STREET 2:** SUITE 650
- **CITY:** LOS ANGELES
- **STATE:** CA
- **ZIP:** 90036

**FORMER NAME:**
- **FORMER CONFORMED NAME:** Western Standard, LLC
- **DATE OF NAME CHANGE:** 20160129

**FORMER NAME:**
- **FORMER CONFORMED NAME:** Western Standard LLC
- **DATE OF NAME CHANGE:** 20110408
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** WESTERN STANDARD PARTNERS LP
- **CENTRAL INDEX KEY:** 0001450414
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-35409
- **FILM NUMBER:** 23752979

**BUSINESS ADDRESS:**
- **STREET 1:** 5900 WILSHIRE BLVD
- **STREET 2:** SUITE 650
- **CITY:** LOS ANGELES
- **STATE:** CA
- **ZIP:** 90036
- **BUSINESS PHONE:** 310-929-4300

**MAIL ADDRESS:**
- **STREET 1:** 5900 WILSHIRE BLVD
- **STREET 2:** SUITE 650
- **CITY:** LOS ANGELES
- **STATE:** CA
- **ZIP:** 90036
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Western Standard Partners QP, L.P.
- **CENTRAL INDEX KEY:** 0001544857
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-35409
- **FILM NUMBER:** 23752978

**BUSINESS ADDRESS:**
- **STREET 1:** 5900 WILSHIRE BLVD
- **STREET 2:** SUITE 650
- **CITY:** LOS ANGELES
- **STATE:** CA
- **ZIP:** 90036
- **BUSINESS PHONE:** 3109294300

**MAIL ADDRESS:**
- **STREET 1:** 5900 WILSHIRE BLVD
- **STREET 2:** SUITE 650
- **CITY:** LOS ANGELES
- **STATE:** CA
- **ZIP:** 90036
**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Andersen Eric
- **CENTRAL INDEX KEY:** 0001517667

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-35409
- **FILM NUMBER:** 23752980

**MAIL ADDRESS:**
- **STREET 1:** 1507 BERKELEY ST
- **STREET 2:** SUITE 7
- **CITY:** SANTA MONICA
- **STATE:** X1
- **ZIP:** 90404
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** MERRIMACK PHARMACEUTICALS INC
- **CENTRAL INDEX KEY:** 0001274792
- **STANDARD INDUSTRIAL CLASSIFICATION:** PHARMACEUTICAL PREPARATIONS [2834]
- **IRS NUMBER:** 000000000
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** ONE BROADWAY
- **STREET 2:** 14TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142
- **BUSINESS PHONE:** 617-441-1000

**MAIL ADDRESS:**
- **STREET 1:** ONE BROADWAY
- **STREET 2:** 14TH FLOOR
- **CITY:** CAMBRIDGE
- **STATE:** MA
- **ZIP:** 02142

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

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

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

[ ] Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Andersen Eric<br><sub>(Last) (First) (Middle)</sub><br>5900 WILSHIRE BOULEVARD, SUITE 650<br><sub>(Street)</sub><br>LOS ANGELES, CA 90036<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2023-03-21 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [ ] 10% Owner<br>[ ] Officer (give title below) [X] Other (specify below)<br>_See remarks_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>MERRIMACK PHARMACEUTICALS INC [ MACK ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Western Standard LLC<br><sub>(Last) (First) (Middle)</sub><br>5900 WILSHIRE BOULEVARD, SUITE 650<br><sub>(Street)</sub><br>LOS ANGELES, CA 90036<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2023-03-21 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [ ] 10% Owner<br>[ ] Officer (give title below) [X] Other (specify below)<br>_See Remarks_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>MERRIMACK PHARMACEUTICALS INC [ MACK ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>WESTERN STANDARD PARTNERS LP<br><sub>(Last) (First) (Middle)</sub><br>5900 WILSHIRE BOULEVARD, SUITE 650<br><sub>(Street)</sub><br>LOS ANGELES, CA 90036<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2023-03-21 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [ ] 10% Owner<br>[ ] Officer (give title below) [X] Other (specify below)<br>_See Remarks_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>MERRIMACK PHARMACEUTICALS INC [ MACK ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

---

| | | |
|:---|:---|:---|
| **1. Name and Address of Reporting Person**<sup>*</sup><br>Western Standard Partners QP, L.P.<br><sub>(Last) (First) (Middle)</sub><br>5900 WILSHIRE BOULEVARD, SUITE 650<br><sub>(Street)</sub><br>LOS ANGELES, CA 90036<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2023-03-21 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[ ] Director [ ] 10% Owner<br>[ ] Officer (give title below) [X] Other (specify below)<br>_See Remarks_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>MERRIMACK PHARMACEUTICALS INC [ MACK ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[ ] Form filed by One Reporting Person<br>[X] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Common Stock | 2023-03-21 |  | P |  | 127409 | A | $11.52 | 1412044 | I | See footnote<sup>(1)</sup> |
| Common Stock | 2023-03-21 |  | P |  | 33181 | A | $11.52 | 357514 | I | See footnote<sup>(2)</sup> |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

---

### Footnotes:

(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, L.P. ("WSP") and Western Standard Partners QP, L.P. ("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 3,643,252 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 25.6% 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.

**Signature:** /s/ Eric D. Andersen  
**Date:** 2023-03-22

**Signature:** Western Standard, LLC; /s/ Eric D. Andersen, Managing Member  
**Date:** 2023-03-22

**Signature:** Western Standard Partners, L.P.; By: Western Standard, LLC, General Partner; /s/ Eric D. Andersen, Managing Member  
**Date:** 2023-03-22

**Signature:** Western Standard Partners QP, L.P.; By: Western Standard, LLC, General Partner; /s/ Eric D. Andersen, Managing Member  
**Date:** 2023-03-22

### Remarks:

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).

** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.

**Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.**