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    CONFORMED SUBMISSION TYPE:	424B4
    PUBLIC DOCUMENT COUNT:		27
    FILED AS OF DATE:		20200130
    DATE AS OF CHANGE:		20200130

    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:		424B4
    		SEC ACT:		1933 Act
    		SEC FILE NUMBER:	333-236094
    		FILM NUMBER:		20559921

    	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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