<SEC-DOCUMENT>0001193125-17-230096-index.html : 20170718
<SEC-HEADER>0001193125-17-230096.hdr.sgml : 20170718
<ACCEPTANCE-DATETIME>20170718132913
ACCESSION NUMBER:		0001193125-17-230096
CONFORMED SUBMISSION TYPE:	497
PUBLIC DOCUMENT COUNT:		16
FILED AS OF DATE:		20170718
DATE AS OF CHANGE:		20170718
EFFECTIVENESS DATE:		20170718

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COLUMBIA ACORN TRUST
		CENTRAL INDEX KEY:			0000002110
		IRS NUMBER:				362692100
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		497
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	002-34223
		FILM NUMBER:		17969148

	BUSINESS ADDRESS:	
		STREET 1:		227 W MONROE STE 3000
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
		BUSINESS PHONE:		3126349200

	MAIL ADDRESS:	
		STREET 1:		227 W MONROE STE 3000
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	LIBERTY ACORN TRUST
		DATE OF NAME CHANGE:	20010424

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ACORN INVESTMENT TRUST
		DATE OF NAME CHANGE:	19940204

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ACORN FUND INC
		DATE OF NAME CHANGE:	19920703
<SERIES-AND-CLASSES-CONTRACTS-DATA>
<EXISTING-SERIES-AND-CLASSES-CONTRACTS>
<SERIES>
<OWNER-CIK>0000002110
<SERIES-ID>S000033621
<SERIES-NAME>Columbia Acorn European Fund
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000103324
<CLASS-CONTRACT-NAME>Columbia Acorn European Fund Class A
<CLASS-CONTRACT-TICKER-SYMBOL>CAEAX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000103325
<CLASS-CONTRACT-NAME>Columbia Acorn European Fund Class C
<CLASS-CONTRACT-TICKER-SYMBOL>CAECX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000103327
<CLASS-CONTRACT-NAME>Columbia Acorn European Fund Class Z
<CLASS-CONTRACT-TICKER-SYMBOL>CAEZX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000122752
<CLASS-CONTRACT-NAME>Columbia Acorn European Fund Class R5
<CLASS-CONTRACT-TICKER-SYMBOL>CAEEX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000144049
<CLASS-CONTRACT-NAME>Columbia Acorn European Fund Class R4
<CLASS-CONTRACT-TICKER-SYMBOL>CLOFX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000171393
<CLASS-CONTRACT-NAME>Columbia Acorn European Fund Class Y
<CLASS-CONTRACT-TICKER-SYMBOL>CAEYX
</CLASS-CONTRACT>
</SERIES>
<SERIES>
<OWNER-CIK>0000002110
<SERIES-ID>S000033622
<SERIES-NAME>Columbia Acorn Emerging Markets Fund
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000103328
<CLASS-CONTRACT-NAME>Columbia Acorn Emerging Markets Fund Class A
<CLASS-CONTRACT-TICKER-SYMBOL>CAGAX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000103329
<CLASS-CONTRACT-NAME>Columbia Acorn Emerging Markets Fund Class C
<CLASS-CONTRACT-TICKER-SYMBOL>CGMCX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000103331
<CLASS-CONTRACT-NAME>Columbia Acorn Emerging Markets Fund Class Z
<CLASS-CONTRACT-TICKER-SYMBOL>CEFZX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000122753
<CLASS-CONTRACT-NAME>Columbia Acorn Emerging Markets Fund Class R4
<CLASS-CONTRACT-TICKER-SYMBOL>CAERX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000122754
<CLASS-CONTRACT-NAME>Columbia Acorn Emerging Markets Fund Class R5
<CLASS-CONTRACT-TICKER-SYMBOL>CANRX
</CLASS-CONTRACT>
<CLASS-CONTRACT>
<CLASS-CONTRACT-ID>C000128887
<CLASS-CONTRACT-NAME>Columbia Acorn Emerging Markets Fund Class Y
<CLASS-CONTRACT-TICKER-SYMBOL>CPHRX
</CLASS-CONTRACT>
</SERIES>
</EXISTING-SERIES-AND-CLASSES-CONTRACTS>
</SERIES-AND-CLASSES-CONTRACTS-DATA>
</SEC-HEADER>
<DOCUMENT>
<TYPE>497
<SEQUENCE>1
<FILENAME>d260744d497.htm
<DESCRIPTION>COLUMBIA ACORN TRUST
<TEXT>
Document 1 - file: d260744d497.htm
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</DOCUMENT> <DOCUMENT> <TYPE>EX-101.DEF <SEQUENCE>5 <FILENAME>cat-20170707_def.xml <DESCRIPTION>XBRL TAXONOMY EXTENSION DEFINITION LINKBASE <TEXT> Document 5 - file: cat-20170707_def.xml
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</DOCUMENT> <DOCUMENT> <TYPE>EXCEL <SEQUENCE>12 <FILENAME>Financial_Report.xlsx <DESCRIPTION>IDEA: XBRL DOCUMENT <TEXT> Document 12 - file: Financial_Report.xlsx
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Document 16 - RAW XML: FilingSummary.xml
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