<SEC-DOCUMENT>0001085146-20-000534-index.html : 20200210
<SEC-HEADER>0001085146-20-000534.hdr.sgml : 20200210
<ACCEPTANCE-DATETIME>20200210165429
ACCESSION NUMBER:		0001085146-20-000534
CONFORMED SUBMISSION TYPE:	SC 13G
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20200210
DATE AS OF CHANGE:		20200210

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Aegion Corp
		CENTRAL INDEX KEY:			0000353020
		STANDARD INDUSTRIAL CLASSIFICATION:	WATER, SEWER, PIPELINE, COMM AND POWER LINE CONSTRUCTION [1623]
		IRS NUMBER:				133032158
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-35120
		FILM NUMBER:		20592680

	BUSINESS ADDRESS:	
		STREET 1:		17988 EDISON AVENUE
		CITY:			CHESTERFIELD
		STATE:			MO
		ZIP:			63005
		BUSINESS PHONE:		6365308000

	MAIL ADDRESS:	
		STREET 1:		17988 EDISON AVENUE
		CITY:			CHESTERFIELD
		STATE:			MO
		ZIP:			63005

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INSITUFORM TECHNOLOGIES INC
		DATE OF NAME CHANGE:	19930617

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INSITUFORM OF NORTH AMERICA INC/TN/
		DATE OF NAME CHANGE:	19930617

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INSITUFORM OF NORTH AMERICA INC
		DATE OF NAME CHANGE:	19921217

FILED BY:		

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

	FILING VALUES:
		FORM TYPE:		SC 13G

	BUSINESS ADDRESS:	
		STREET 1:		ONE BEACON STREET
		STREET 2:		30TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02108
		BUSINESS PHONE:		2129089500

	MAIL ADDRESS:	
		STREET 1:		ONE BEACON STREET
		STREET 2:		30TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02108

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Robeco Investment Management, Inc.
		DATE OF NAME CHANGE:	20070111
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G
<SEQUENCE>1
<FILENAME>aegn_21020.htm
<DESCRIPTION>ROBECO INVESTMENT MANAGEMENT INC.
<TEXT>
Document 1 - file: aegn_21020.htm

</DOCUMENT>
</SEC-DOCUMENT>