<SEC-DOCUMENT>0001104659-19-008620-index.html : 20190214
<SEC-HEADER>0001104659-19-008620.hdr.sgml : 20190214
<ACCEPTANCE-DATETIME>20190214140826
ACCESSION NUMBER:		0001104659-19-008620
CONFORMED SUBMISSION TYPE:	SC 13G
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20190214
DATE AS OF CHANGE:		20190214
GROUP MEMBERS:		MERCK SHARP & DOHME CORP.
GROUP MEMBERS:		MRL VENTURES FUND LLC

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Alector, Inc.
		CENTRAL INDEX KEY:			0001653087
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				462702363
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-90858
		FILM NUMBER:		19604450

	BUSINESS ADDRESS:	
		STREET 1:		151 OYSTER POINT BLVD., SUITE 300
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080
		BUSINESS PHONE:		415-231-5660

	MAIL ADDRESS:	
		STREET 1:		151 OYSTER POINT BLVD., SUITE 300
		CITY:			SOUTH SAN FRANCISCO
		STATE:			CA
		ZIP:			94080

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Alector LLC
		DATE OF NAME CHANGE:	20150915

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Merck & Co., Inc.
		CENTRAL INDEX KEY:			0000310158
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		IRS NUMBER:				221918501
		STATE OF INCORPORATION:			NJ
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G

	BUSINESS ADDRESS:	
		STREET 1:		2000 GALLOPING HILL ROAD
		CITY:			KENILWORTH
		STATE:			NJ
		ZIP:			07033
		BUSINESS PHONE:		908-740-4000

	MAIL ADDRESS:	
		STREET 1:		2000 GALLOPING HILL ROAD
		CITY:			KENILWORTH
		STATE:			NJ
		ZIP:			07033

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Merck & Co. Inc.
		DATE OF NAME CHANGE:	20091103

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SCHERING PLOUGH CORP
		DATE OF NAME CHANGE:	19920703
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G
<SEQUENCE>1
<FILENAME>a19-4731_1sc13g.htm
<DESCRIPTION>SC 13G
<TEXT>
Document 1 - file: a19-4731_1sc13g.htm

</DOCUMENT>
</SEC-DOCUMENT>