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<ACCEPTANCE-DATETIME>20190326163531
ACCESSION NUMBER:		0001564590-19-009358
CONFORMED SUBMISSION TYPE:	10-K
PUBLIC DOCUMENT COUNT:		27
CONFORMED PERIOD OF REPORT:	20181231
FILED AS OF DATE:		20190326
DATE AS OF CHANGE:		20190326

FILER:

	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:		10-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38792
		FILM NUMBER:		19705677

	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
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