497 1 d141014d497.htm COLUMBIA ACORN TRUST Columbia Acorn Trust
Supplement dated April 15, 2021
to the Prospectus and Summary Prospectus, as supplemented (as applicable), of the following fund (the Fund):
Fund Prospectus and Summary Prospectus Dated
Columbia Acorn Trust  
 Columbia Acorn European FundSM May 1, 2020
Effective May 1, 2021 (the Effective Date), the portfolio manager information under the caption “Fund Management” in the Summary Prospectus and in the "Summary of the Fund" section of the Prospectus is hereby superseded and replaced with the following:
    
Portfolio Manager   Title   Role with Fund   Service with the Fund Since
Stephen Kusmierczak, CFA   International Team Head, Portfolio Manager and Analyst   Portfolio Manager or Co-Portfolio
Manager since inception in 2011 		  2011
Sebastien Pigeon, CFA   Portfolio Manager and Analyst   Co-Portfolio Manager
since May 2021 		  2015
On the Effective Date, the caption “Portfolio Manager" and the information under that caption in the "Primary Service Providers” sub-section of the “More Information About the Fund" section of the Prospectus is hereby superseded and replaced with the following:
Portfolio Managers
Information about the portfolio managers primarily responsible for overseeing the Fund’s investments is shown below. The SAI provides additional information about the portfolio managers, including information relating to compensation, other accounts managed by the portfolio managers, and ownership by the portfolio managers of Fund shares.
    
Portfolio Manager   Title   Role with Fund   Service with the Fund Since
Stephen Kusmierczak, CFA   International Team Head, Portfolio Manager and Analyst   Portfolio Manager or Co-Portfolio
Manager since inception in 2011 		  2011
Sebastien Pigeon, CFA   Portfolio Manager and Analyst   Co-Portfolio Manager
since May 2021 		  2015
Mr. Kusmierczak has been associated with the Investment Manager or its predecessors as an investment professional since 2001, has been President or Co-President of the Trust since 2020, and was a Vice President of the Trust from 2011-2020. Mr. Kusmierczak began his investment career in 1999 and earned a B.A. from Bowdoin College and an M.P.A. from the Princeton School of Public and International Affairs.
Mr. Pigeon has been associated with the Investment Manager as an investment professional since 2015 and has been a Vice President of the Trust since 2021. Mr. Pigeon began his investment career in 1997 and earned a B.A. from the Political Institute of Lyon and an M.B.A. from the KEDGE Business School.
The rest of the section remains unchanged.
Shareholders should retain this Supplement for future reference.
SUP109_12_005_(04/21)

Supplement dated April 15, 2021
to the Prospectus and Summary Prospectus, as supplemented, of the following Fund:
Fund Prospectus and Summary Prospectus Dated
Columbia Acorn Trust  
 Columbia Acorn® Fund May 1, 2020
Effective April 15, 2021 (the Effective Date), the portfolio manager information under the caption “Fund Management” in the Summary Prospectus and in the "Summary of the Fund" section of the Prospectus is hereby superseded and replaced with the following:
    
Portfolio Manager   Title   Role with Fund   Service with the Fund Since
Daniel Cole, CFA   Senior Portfolio Manager of Columbia Management and Vice President of the Investment Manager   Co-Portfolio Manager since April 2021   2021
Erika K. Maschmeyer, CFA   Director of Research (U.S.), Portfolio Manager and Analyst at the Investment Manager   Co-Portfolio Manager since 2019   2016
John L. Emerson, CFA   Portfolio Manager and Analyst at the Investment Manager   Co-Portfolio Manager since April 2021   2003
The rest of the section remains unchanged.
On the Effective Date, the information under the caption “Primary Service Providers - The Investment Manager” in the “More Information About the Fund" section of the Prospectus is hereby revised to add the following:
The Investment Manager and its investment advisory affiliates, including Columbia Management (Affiliates), around the world may coordinate in providing services to their clients. From time to time, the Investment Manager may engage its Affiliates to provide a variety of services such as investment research, investment monitoring, trading, and discretionary investment management (including portfolio management) to certain accounts managed by the Investment Manager, including the Fund. These Affiliates will provide services to these accounts of the Investment Manager either pursuant to delegation agreements, personnel-sharing agreements or similar inter-company or other arrangements or relationships and the Fund will pay no additional fees and expenses as a result of any such arrangements or relationships. These Affiliates, like the Investment Manager, are direct or indirect subsidiaries of Ameriprise Financial and are registered with the appropriate respective regulators and, where required, the SEC and the Commodity Futures Trading Commission in the United States.
Pursuant to some of these arrangements or relationships, certain personnel of Columbia Management and other Affiliates may serve as “associated persons” or officers of the Investment Manager and, in this capacity, subject to the oversight and supervision of the Investment Manager and consistent with the investment objectives, policies and limitations set forth in this prospectus and the Fund's SAI, and with the Investment Manager’s and the Funds’ compliance policies and procedures, may provide such services to the Fund.
The rest of the section remains unchanged.
On the Effective Date, the information about the portfolio managers under the caption “Primary Service Providers - Portfolio Managers” in the “More Information About the Fund" section of the Prospectus is hereby superseded and replaced with the following:
    
Portfolio Manager   Title   Role with Fund   Service with the Fund Since
Daniel Cole, CFA   Senior Portfolio Manager of Columbia Management and Vice President of the Investment Manager   Co-Portfolio Manager since April 2021   2021
Erika K. Maschmeyer, CFA   Director of Research (U.S.), Portfolio Manager and Analyst at the Investment Manager   Co-Portfolio Manager since 2019   2016
John L. Emerson, CFA   Portfolio Manager and Analyst at the Investment Manager   Co-Portfolio Manager since April 2021   2003
Mr. Cole joined Columbia Management, an affiliate of the Investment Manager, in 2014 and has served as a Vice President of the Investment Manager since April 2021. Mr. Cole began his investment career in 1993 and earned a B.S. from Guilford College and an M.B.A. in finance from Virginia Polytechnic Institute and State University.
Ms. Maschmeyer has been associated with the Investment Manager as an investment professional since 2016. Ms. Maschmeyer heads the Investment Manager's U.S. equity research efforts and has been a Vice President of the Trust since March 2020. Prior to joining the Investment Manager, Ms. Maschmeyer was a research analyst at an
SUP110_12_009_(04/21)

 

investment advisory firm where she was responsible for U.S. consumer discretionary/staples investments. Ms. Maschmeyer began her investment career in 2001 and earned a B.A. from Denison University and an M.B.A from the University of Chicago.
Mr. Emerson has been associated with the Investment Manager or its predecessors as an investment professional since 2003 and has been a Vice President of the Trust since March 2020. Prior to joining the Investment Manager, Mr. Emerson was an analyst at an equity research firm. Mr. Emerson began his investment career in 2002 and earned a B.S. from the University of Missouri and an M.B.A from the University of Chicago.
The rest of the section remains unchanged.
Shareholders should retain this Supplement for future reference.
2
SUP110_12_009_(04/21)

Supplement dated April 15, 2021
to the Prospectus and Summary Prospectus, as supplemented, of the following fund (the Fund):
Fund Prospectus and Summary Prospectus Dated
Columbia Acorn Trust  
 Columbia Acorn USA® May 1, 2020
Effective April 15, 2021 (the Effective Date), the portfolio manager information under the caption “Fund Management” in the Summary Prospectus and in the "Summary of the Fund" section of the Prospectus is hereby superseded and replaced with the following:
    
Portfolio Manager   Title   Role with Fund   Service with the Fund Since
Erika K. Maschmeyer, CFA   Director of Research (U.S.), Portfolio Manager and Analyst   Co-Portfolio Manager since April 2021   2016
John L. Emerson, CFA   Portfolio Manager and Analyst   Co-Portfolio Manager since April 2021   2003
On the Effective Date, the portfolio manager information under the caption “Primary Service Providers - Portfolio Managers” in the “More Information About the Fund" section of the Prospectus is hereby superseded and replaced with the following:
    
Portfolio Manager   Title   Role with Fund   Service with the Fund Since
Erika K. Maschmeyer, CFA   Director of Research (U.S.), Portfolio Manager and Analyst   Co-Portfolio Manager since April 2021   2016
John L. Emerson, CFA   Portfolio Manager and Analyst   Co-Portfolio Manager since April 2021   2003
Ms. Maschmeyer has been associated with the Investment Manager as an investment professional since 2016. Ms. Maschmeyer heads the Investment Manager's U.S. equity research efforts and has been a Vice President of the Trust since March 2020. Prior to joining the Investment Manager, Ms. Maschmeyer was a research analyst at an investment advisory firm where she was responsible for U.S. consumer discretionary/staples investments. Ms. Maschmeyer began her investment career in 2001 and earned a B.A. from Denison University and an M.B.A from the University of Chicago.
Mr. Emerson has been associated with the Investment Manager or its predecessors as an investment professional since 2003 and has been a Vice President of the Trust since March 2020. Prior to joining the Investment Manager, Mr. Emerson was an analyst at an equity research firm. Mr. Emerson began his investment career in 2002 and earned a B.S. from the University of Missouri and an M.B.A from the University of Chicago.
The rest of the section remains unchanged.
Shareholders should retain this Supplement for future reference.
SUP115_12_007_(04/21)