<SEC-DOCUMENT>0001193125-22-105697-index.html : 20220414
<SEC-HEADER>0001193125-22-105697.hdr.sgml : 20220414
<ACCEPTANCE-DATETIME>20220414165600
ACCESSION NUMBER:		0001193125-22-105697
CONFORMED SUBMISSION TYPE:	SC 13D/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20220414
DATE AS OF CHANGE:		20220414
GROUP MEMBERS:		BCIP LIFE SCIENCES ASSOCIATES, LP
GROUP MEMBERS:		BCLS II INVESTCO, LP

SUBJECT COMPANY:	

	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

	FILING VALUES:
		FORM TYPE:		SC 13D/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-90033
		FILM NUMBER:		22827993

	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

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Bain Capital Life Sciences Fund II, L.P.
		CENTRAL INDEX KEY:			0001773187
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			E9
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13D/A

	BUSINESS ADDRESS:	
		STREET 1:		200 CLARENDON STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
		BUSINESS PHONE:		6175162000

	MAIL ADDRESS:	
		STREET 1:		200 CLARENDON STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13D/A
<SEQUENCE>1
<FILENAME>d363589dsc13da.htm
<DESCRIPTION>SC 13D/A
<TEXT>
Document 1 - file: d363589dsc13da.htm

</DOCUMENT>
</SEC-DOCUMENT>