<SEC-DOCUMENT>0000354204-22-001490-index.html : 20220208
<SEC-HEADER>0000354204-22-001490.hdr.sgml : 20220208
<ACCEPTANCE-DATETIME>20220208155239
ACCESSION NUMBER:		0000354204-22-001490
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20220208
DATE AS OF CHANGE:		20220208

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ALLEGHENY TECHNOLOGIES INC
		CENTRAL INDEX KEY:			0001018963
		STANDARD INDUSTRIAL CLASSIFICATION:	STEEL PIPE & TUBES [3317]
		IRS NUMBER:				251792394
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-46715
		FILM NUMBER:		22601031

	BUSINESS ADDRESS:	
		STREET 1:		1000 SIX PPG PLACE
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15222
		BUSINESS PHONE:		4123942800

	MAIL ADDRESS:	
		STREET 1:		100 SIX PPG PLACE
		CITY:			PITTSBURGH
		STATE:			PA
		ZIP:			15222

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ALLEGHENY TELEDYNE INC
		DATE OF NAME CHANGE:	19960716

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			DIMENSIONAL FUND ADVISORS LP
		CENTRAL INDEX KEY:			0000354204
		STANDARD INDUSTRIAL CLASSIFICATION:	UNKNOWN SIC - 0000 [0000]
		IRS NUMBER:				222370029
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		6300 BEE CAVE ROAD
		STREET 2:		BUILDING ONE
		CITY:			AUSTIN
		STATE:			TX
		ZIP:			78746
		BUSINESS PHONE:		(512) 306-7400

	MAIL ADDRESS:	
		STREET 1:		6300 BEE CAVE ROAD
		STREET 2:		BUILDING ONE
		CITY:			AUSTIN
		STATE:			TX
		ZIP:			78746

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	DIMENSIONAL FUND ADVISORS INC
		DATE OF NAME CHANGE:	19920929
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>SEC13G_Filing.htm
<DESCRIPTION>SEC SCHEDULE 13G
<TEXT>
Document 1 - file: SEC13G_Filing.htm

</DOCUMENT>
</SEC-DOCUMENT>