<SEC-DOCUMENT>0001085146-18-002820-index.html : 20181207
<SEC-HEADER>0001085146-18-002820.hdr.sgml : 20181207
<ACCEPTANCE-DATETIME>20181207135259
ACCESSION NUMBER:		0001085146-18-002820
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20181207
DATE AS OF CHANGE:		20181207

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			STEEL DYNAMICS INC
		CENTRAL INDEX KEY:			0001022671
		STANDARD INDUSTRIAL CLASSIFICATION:	STEEL WORKS, BLAST FURNACES  ROLLING MILLS (COKE OVENS) [3312]
		IRS NUMBER:				351929476
		STATE OF INCORPORATION:			IN
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-49143
		FILM NUMBER:		181223004

	BUSINESS ADDRESS:	
		STREET 1:		7575 W JEFFERSON BLVD
		CITY:			FORT WAYNE
		STATE:			IN
		ZIP:			46804
		BUSINESS PHONE:		260 459 3553

	MAIL ADDRESS:	
		STREET 1:		7575 W JEFFERSON BLVD
		CITY:			FORT WAYNE
		STATE:			IN
		ZIP:			46804

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Boston Partners
		CENTRAL INDEX KEY:			0001386060
		IRS NUMBER:				980202744
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		ONE BEACON STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02108
		BUSINESS PHONE:		2129089500

	MAIL ADDRESS:	
		STREET 1:		909 THIRD AVENUE
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10022

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Robeco Investment Management, Inc.
		DATE OF NAME CHANGE:	20070111
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>stlda1_120718.htm
<DESCRIPTION>ROBECO INVESTMENT MANAGEMENT INC.
<TEXT>
Document 1 - file: stlda1_120718.htm

</DOCUMENT>
</SEC-DOCUMENT>