<SEC-DOCUMENT>0001193125-25-095335-index.html : 20250425 <SEC-HEADER>0001193125-25-095335.hdr.sgml : 20250425 <ACCEPTANCE-DATETIME>20250425095332 ACCESSION NUMBER: 0001193125-25-095335 CONFORMED SUBMISSION TYPE: 485BPOS PUBLIC DOCUMENT COUNT: 47 FILED AS OF DATE: 20250425 DATE AS OF CHANGE: 20250425 EFFECTIVENESS DATE: 20250501 FILER: COMPANY DATA: COMPANY CONFORMED NAME: COLUMBIA ACORN TRUST CENTRAL INDEX KEY: 0000002110 ORGANIZATION NAME: EIN: 362692100 STATE OF INCORPORATION: MA FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: 485BPOS SEC ACT: 1940 Act SEC FILE NUMBER: 811-01829 FILM NUMBER: 25870633 BUSINESS ADDRESS: STREET 1: 71 S. WACKER DRIVE, SUITE 2500 CITY: CHICAGO STATE: IL ZIP: 60606 BUSINESS PHONE: 3126349200 MAIL ADDRESS: STREET 1: 71 S. WACKER DRIVE, SUITE 2500 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 FILER: COMPANY DATA: COMPANY CONFORMED NAME: COLUMBIA ACORN TRUST CENTRAL INDEX KEY: 0000002110 ORGANIZATION NAME: EIN: 362692100 STATE OF INCORPORATION: MA FISCAL YEAR END: 1231 FILING VALUES: FORM TYPE: 485BPOS SEC ACT: 1933 Act SEC FILE NUMBER: 002-34223 FILM NUMBER: 25870632 BUSINESS ADDRESS: STREET 1: 71 S. WACKER DRIVE, SUITE 2500 CITY: CHICAGO STATE: IL ZIP: 60606 BUSINESS PHONE: 3126349200 MAIL ADDRESS: STREET 1: 71 S. WACKER DRIVE, SUITE 2500 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>S000009184 <SERIES-NAME>Columbia Acorn Fund <CLASS-CONTRACT> <CLASS-CONTRACT-ID>C000024954 <CLASS-CONTRACT-NAME>Columbia Acorn Fund Class A <CLASS-CONTRACT-TICKER-SYMBOL>LACAX </CLASS-CONTRACT> <CLASS-CONTRACT> <CLASS-CONTRACT-ID>C000024956 <CLASS-CONTRACT-NAME>Columbia Acorn Fund Class C <CLASS-CONTRACT-TICKER-SYMBOL>LIACX </CLASS-CONTRACT> <CLASS-CONTRACT> <CLASS-CONTRACT-ID>C000024957 <CLASS-CONTRACT-NAME>Columbia Acorn Fund Institutional Class <CLASS-CONTRACT-TICKER-SYMBOL>ACRNX </CLASS-CONTRACT> <CLASS-CONTRACT> <CLASS-CONTRACT-ID>C000122736 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