Columbia Acorn Trust

07/17/2026 | Press release | Distributed by Public on 07/17/2026 06:27

Prospectus by Investment Company (Form 497)

Supplement dated July 17, 2026
to the Statement of Additional Information (SAI), dated July 1, 2026, for the following fund: 
Fund
Columbia Acorn Trust
 Columbia Acorn® Fund
Effective immediately, the information under the subsection "The Investment Manager and Subadvisers - Portfolio Managers" in the "Investment Management and Other Services" section of the SAI for Columbia Acorn® Fund (Acorn Fund) is hereby superseded and replaced with the following: 
Other Accounts Managed (Excluding the Fund)
Ownership
of Fund
Shares
Potential
Conflicts
of Interest
Structure
of
Compensation
Fund
Portfolio
Manager
Number
and Type
of Account*
Approximate
Total Net
Assets
Performance-
Based
Accounts**
For Funds with fiscal year ending December 31 - Information is as of December 31, 2025, unless otherwise noted
Acorn
Fund
Nicolas Janvier(l)
1 RIC
3 PIVs
2 other
accounts
$11.66 million
$3.09 billion
$0.44 million
None
None
Columbia
Management
Columbia
Management
Pratyasha Rath
1 RIC
7 other
accounts
$470.60 million
$1.18 million
None
$10,001 -
$50,000(b)
*
RIC refers to a Registered Investment Company; PIV refers to a Pooled Investment Vehicle.
**
Number and type of accounts for which the advisory fee paid is based in part or wholly on performance and the aggregate net assets in those accounts.
(b)
Notional investments through a deferred compensation account.
(l)
The portfolio manager began managing the Fund after its last fiscal year end; reporting information is provided as of May 31, 2026.
The rest of the section remains the same.
Shareholders should retain this Supplement for future reference.
SUP910_00_049_(07/26)
Columbia Acorn Trust published this content on July 17, 2026, and is solely responsible for the information contained herein. Distributed via EDGAR on July 17, 2026 at 12:27 UTC. If you believe the information included in the content is inaccurate or outdated and requires editing or removal, please contact us at [email protected]