Merrimack Pharmaceuticals (MACK) Form 3 MERRIMACK PHARMACEUTICALS / Daryl C Drummond ownership change

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^*

Drummond Daryl C

(Last) (First) (Middle)

C/O MERRIMACK PHARMACEUTICALS, INC.

ONE KENDALL SQUARE, SUITE B7201

(Street)

CAMBRIDGE MA 02139

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
03/31/2017

3. Issuer Name and Ticker or Trading Symbol
MERRIMACK PHARMACEUTICALS INC [ MACK ]

4. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director	10% Owner
X	Officer (give title below)	Other (specify below)
Head of Research

5. If Amendment, Date of Original Filed (Month/Day/Year)

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 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	92,420	D
Common Stock	9,311	I	By Wife

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
Stock Option (right to buy)	(1)	02/01/2020	Common Stock	80,000	2.12	D
Stock Option (right to buy)	(1)	10/15/2020	Common Stock	27,500	2.69	D
Stock Option (right to buy)	(1)	05/03/2021	Common Stock	20,000	5.54	D
Stock Option (right to buy)	(1)	08/22/2022	Common Stock	14,100	7.53	D
Stock Option (right to buy)	(1)	03/11/2023	Common Stock	50,000	6.35	D
Stock Option (right to buy)	(1)	02/10/2024	Common Stock	30,000	5.02	D
Stock Option (right to buy)	(2)	02/08/2025	Common Stock	32,500	9.08	D
Stock Option (right to buy)	(3)	02/07/2026	Common Stock	42,000	5.42	D
Stock Option (right to buy)	(1)	07/03/2017	Common Stock	4,097	2.69	I	By Wife
Stock Option (right to buy)	(1)	07/03/2017	Common Stock	900	5.54	I	By Wife
Stock Option (right to buy)	(1)	06/02/2017	Common Stock	1,400	7.53	I	By Wife
Stock Option (right to buy)	(1)	06/02/2017	Common Stock	1,700	6.35	I	By Wife
Stock Option (right to buy)	(1)	06/02/2017	Common Stock	1,796	5.02	I	By Wife
Stock Option (right to buy)	(1)	06/02/2017	Common Stock	599	9.08	I	By Wife
Stock Option (right to buy)	(1)	06/02/2017	Common Stock	333	5.42	I	By Wife

Explanation of Responses:

1. This option is fully vested.

2. This option vested as to 1/12th of the total number of shares on 5/9/15 and an additional 1/12th of the total number of shares at the end of each successive three month period thereafter until 2/9/18.

3. This option vested as to 1/12th of the total number of shares on 5/8/16 and an additional 1/12th of the total number of shares at the end of each successive three month period thereafter until 2/8/19.

Remarks:

	/s/ Brian J. Kickham, attorney-in-fact	04/10/2017
	** Signature of Reporting Person	Date
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 5 (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.
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