Barris Peter J Form 3 Mersana Therapeutics / PETER J BARRIS 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^*

BARRIS PETER J

(Last) (First) (Middle)

1954 GREENSPRING DRIVE

SUITE 600

(Street)

TIMONIUM MD 21093

(City) (State) (Zip)

2. Date of Event Requiring Statement (Month/Day/Year)
06/27/2017

3. Issuer Name and Ticker or Trading Symbol
Mersana Therapeutics, Inc. [ MRSN ]

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

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

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)

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
Series A-1 Preferred Stock	(1)	(1)	Common Stock	2,647,241	(1)	I	See Note 2(2)
Series B-1 Preferred Stock	(3)	(3)	Common Stock	4,000,314	(3)	I	See Note 2(2)
Series C-1 Preferred Stock	(4)	(4)	Common Stock	492,583	(4)	I	See Note 2(2)
Stock Purchase Warrant (right to buy)	09/27/2013	09/27/2023	Common Stock	70,593	0.05	I	See Note 2(2)

Explanation of Responses:

1. The Series A-1 Convertible Preferred Stock is convertible into shares of common stock at any time at the holder's election and automatically upon the consummation of a public offering of the registrant. There is no expiration date for the Series A-1 Convertible Preferred Stock.

2. The Reporting Person is a director of NEA 14 GP, LTD, which is the sole general partner of NEA Partners 14, L.P. ("NEA Partners 14"). NEA Partners 14 is the sole general partner of New Enterprise Associates 14, L.P. ("NEA 14"), which is the direct beneficial owner of the securities. The Reporting Person disclaims beneficial ownership, within the meaning of Section 16 of the Securities Exchange Act of 1934, as amended, or otherwise of such portion of the NEA 14 shares in which the Reporting Person has no pecuniary interest.

3. The Series B-1 Convertible Preferred Stock is convertible into shares of common stock at any time at the holder's election and automatically upon the consummation of a public offering of the registrant. There is no expiration date for the Series B-1 Convertible Preferred Stock.

4. The Series C-1 Convertible Preferred Stock is convertible into shares of common stock at any time at the holder's election and automatically upon the consummation of a public offering of the registrant. There is no expiration date for the Series C-1 Convertible Preferred Stock.

Remarks:

	/s/ Sasha Keough, attorney-in-fact	06/27/2017
	** 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).
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