<SEC-DOCUMENT>0001209191-17-042048-index.html : 20170627
<SEC-HEADER>0001209191-17-042048.hdr.sgml : 20170627
<ACCEPTANCE-DATETIME>20170627201452
ACCESSION NUMBER:		0001209191-17-042048
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170627
FILED AS OF DATE:		20170627
DATE AS OF CHANGE:		20170627

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Mersana Therapeutics, Inc.
		CENTRAL INDEX KEY:			0001442836
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		840 MEMORIAL DRIVE
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139
		BUSINESS PHONE:		617-498-0020

	MAIL ADDRESS:	
		STREET 1:		840 MEMORIAL DRIVE
		CITY:			CAMBRIDGE
		STATE:			MA
		ZIP:			02139

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MERSANA THERAPEUTICS INC
		DATE OF NAME CHANGE:	20080813

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			NEA 14 GP, LTD
		CENTRAL INDEX KEY:			0001551532
		STATE OF INCORPORATION:			E9
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38129
		FILM NUMBER:		17933541

	BUSINESS ADDRESS:	
		STREET 1:		1954 GREENSPRING DRIVE
		STREET 2:		SUITE 600
		CITY:			TIMONIUM
		STATE:			MD
		ZIP:			21093
		BUSINESS PHONE:		410-842-4000

	MAIL ADDRESS:	
		STREET 1:		1954 GREENSPRING DRIVE
		STREET 2:		SUITE 600
		CITY:			TIMONIUM
		STATE:			MD
		ZIP:			21093

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			NEA Partners 14, L.P.
		CENTRAL INDEX KEY:			0001551531
		STATE OF INCORPORATION:			E9
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38129
		FILM NUMBER:		17933542

	BUSINESS ADDRESS:	
		STREET 1:		1954 GREENSPRING DRIVE
		STREET 2:		SUITE 600
		CITY:			TIMONIUM
		STATE:			MD
		ZIP:			21093
		BUSINESS PHONE:		410-842-4000

	MAIL ADDRESS:	
		STREET 1:		1954 GREENSPRING DRIVE
		STREET 2:		SUITE 600
		CITY:			TIMONIUM
		STATE:			MD
		ZIP:			21093

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			New Enterprise Associates 14, L.P.
		CENTRAL INDEX KEY:			0001544328
		STATE OF INCORPORATION:			E9
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38129
		FILM NUMBER:		17933543

	BUSINESS ADDRESS:	
		STREET 1:		1954 GREENSPRING DRIVE
		STREET 2:		SUITE 600
		CITY:			TIMONIUM
		STATE:			MD
		ZIP:			21093
		BUSINESS PHONE:		410-842-4000

	MAIL ADDRESS:	
		STREET 1:		1954 GREENSPRING DRIVE
		STREET 2:		SUITE 600
		CITY:			TIMONIUM
		STATE:			MD
		ZIP:			21093
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>doc3.xml
<DESCRIPTION>FORM 3 SUBMISSION
<TEXT>
Document 1 - file: doc3.html
Document 1 - RAW XML: doc3.xml
</DOCUMENT> </SEC-DOCUMENT>