<PAGE>
SCHEDULE 14A INFORMATION
Proxy Statement Pursuant to Section 14(a) of the Securities
Exchange Act of 1934 (Amendment No. )
Filed by the Registrant [X]
Filed by a Party other than the Registrant [_]
Check the appropriate box:
[_] Preliminary Proxy Statement [_] CONFIDENTIAL, FOR USE OF THE
COMMISSION ONLY (AS PERMITTED BY
RULE 14A-6(E)(2))
[_] Definitive Proxy Statement
[X] Definitive Additional Materials
[_] Soliciting Material Pursuant to Section 240.14a-11(c) or Section 240.14a-12
Acorn Investment Trust
- --------------------------------------------------------------------------------
(Name of Registrant as Specified In Its Charter)
- --------------------------------------------------------------------------------
(Name of Person(s) Filing Proxy Statement, if other than the Registrant)
Payment of Filing Fee (Check the appropriate box):
[X] No fee required
[_] Fee computed on table below per Exchange Act Rules 14a-6(i)(4) and 0-11.
(1) Title of each class of securities to which transaction applies:
-------------------------------------------------------------------------
(2) Aggregate number of securities to which transaction applies:
-------------------------------------------------------------------------
(3) Per unit price or other underlying value of transaction computed
pursuant to Exchange Act Rule 0-11 (Set forth the amount on which
the filing fee is calculated and state how it was determined):
-------------------------------------------------------------------------
(4) Proposed maximum aggregate value of transaction:
-------------------------------------------------------------------------
(5) Total fee paid:
-------------------------------------------------------------------------
[_] Fee paid previously with preliminary materials.
[_] Check box if any part of the fee is offset as provided by Exchange
Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee
was paid previously. Identify the previous filing by registration statement
number, or the Form or Schedule and the date of its filing.
(1) Amount Previously Paid:
-------------------------------------------------------------------------
(2) Form, Schedule or Registration Statement No.:
-------------------------------------------------------------------------
(3) Filing Party:
-------------------------------------------------------------------------
(4) Date Filed:
-------------------------------------------------------------------------
Notes:
<PAGE>
Acorn Investment Trust
Proposed Fee Adjustment Overview
. For the first time in 27 years, Acorn Fund proposes a fee increase to its
shareholders.
. The purpose is to serve investors better and remain one of the premier small
cap funds.
. The adjustment in no way reflects a change in Acorn Fund's core investment
philosophy.
. Acorn Fund will continue to remain one of the lowest priced small cap funds
in the industry and a solid long-term investment.
[SQUIRREL LOGO]
1
<PAGE>
For the first time in 27 years,
Acorn Fund proposes a fee increase
to its shareholders
We strongly believe Acorn Fund remains an extremely good value for its
shareholders. Acorn Fund's actual and proposed fees and expenses for the 6
months ended 6/30/97 are as follows:
Current Proposed
Acorn Management Fee .44% .69%
Acorn Total Expense Ratio .57% .87%
As you will see on the following pages, the proposed fee is highly competitive
within our industry.
*The total expense ratio represents all fund expenses -- management fee,
shareholder servicing costs, fund accounting, custody costs, transfer agent
costs, legal and reporting fees. There are no additional or hidden costs. The
"proposed" management fee and total expense ratio are pro forma calculations
assuming the proposed fees had been in effect throughout the period.
[SQUIRREL LOGO]
2
<PAGE>
Acorn Fund's proposed total
expense ratio remains well below
the average.
Acorn Fund's total expense ratio, with the fee increase, remains nearly 42%
below that of the average small cap mutual fund.
Proposed Acorn Fund management fee........................ .69%
Average small cap mutual fund management fee.............. .79%
Proposed Acorn Total Expense Ratio........................ .87%
Average small cap mutual fund total expense ratio......... 1.50%
Moreover, of the 396 small company mutual funds tracked by Lipper, 90% of these
funds had total expense ratios in their most recent fiscal years higher than the
total expense ratio proposed for Acorn Fund.
The proposed Acorn Fund total expense ratio and management fee are pro forma
calculations for the six months ended June 30, 1997 assuming the proposed fee
arrangements had been in effect throughout that period. Information on the total
expense ratios and management fees for all small cap funds was prepared by
Lipper Analytical Services, Inc., and includes the most recent available fiscal
year data for all 396 mutual funds (including Acorn Fund) included in the Lipper
small company funds category as of August 20, 1997.
3
<PAGE>
How does the proposed fee compare
with other mutual fund fees?
Acorn Fund's proposed fee is even well below the average general equity mutual
fund fee.*
<TABLE>
<CAPTION>
Retail Taxable General Mid Small
Money Fixed ACORN Equity Cap Cap
Market Income Fund Fund Fund Fund
<S> <C> <C> <C> <C> <C> <C>
Management Fee .36% .49% .69% .73% .76% .79%
Total Expense Ratio .73% 1.08% .87% 1.46% 1.46% 1.50%
</TABLE>
Moreover, there are no hidden costs -- no 12b-1 fees, sales charges, front-end
charges or back-end charges.
*The management fee and total expense ratios for Acorn Fund are proforma figures
for the six months ended June 30, 1997, calculated as if the proposed fees had
been in effect throughout that period. The industry averages are from Lipper
Analytical Services, Inc. and include the most recent fiscal year data available
as of August 16, 1997 for all funds tracked by Lipper in the following
categories: retail money market funds; taxable fixed income funds; general
equity funds, mid cap funds and small cap funds.
4
<PAGE>
Purpose of Acorn Fund's Fee Increase
We want Acorn Fund to remain one of the premier small cap funds and to serve
investors better. The proposed fee increase will give Wanger Asset Management
(WAM) the resources to continue to compete for top analytical talent. WAM will
also have expanded resources to increase its client servicing staff and improve
internal systems.
5
<PAGE>
Good analytical talent is the key
to any fund's success.
. Attracting and retaining top talent is the key to Acorn Fund's continued
success. WAM needs to competitively compensate its analysts.
. WAM analysts receive extensive training and on-going mentoring.
. WAM mantra: "Hire the best, retain the best to provide the best performance."
6
<PAGE>
WAM must maintain the right balance
of analysts to new ideas.
. Finding good small company stocks is very labor intensive. There are more new
companies to choose from than ever before. Currently, there are over 3,400
small cap companies in the U.S. alone.*
. WAM adds value by researching and investing in "lesser known" names. WAM
analysts don't want to buy yesterday's celebrity stocks, they want to invest
in tomorrow's stars.
. In addition to finding new companies, Acorn Fund has over 250 stocks in the
portfolio to track and monitor.
. Currently, there are 396 small company mutual funds competing for new ideas.
To be the first to uncover great stocks, we must stay ahead of the pack.**
*Source: Wilshire Associates, 8/31/97. Based on publicly traded securities with
market capitalization between $100 million and $1 billion.
**Source: Lipper Analytical Services, Inc., 8/31/97.
7
<PAGE>
Does the fee adjustment signal
a change in Acorn's core investment
philosophy or management team?
Absolutely not.
. WAM instills in its analysts and portfolio managers the "Acorn Way" of money
management that started 27 years ago with Irving Harris and Ralph Wanger.
. Our investment approach has proven successful through multiple business
cycles.
. WAM adds value by doing its own homework, rather than following the pack.
Over the years, this philosophy has paid off as Acorn has continued to invest
in great little companies ahead of the pack. Examples include:
-Harley Davidson
-Carnival Cruise Line
-Liberty Media
8
<PAGE>
To serve investors better and remain
one of the premier small cap funds.
. For the first time in the Fund's history, Acorn Fund proposes a fee increase
to shareholders.
. Even with the adjustment, Acorn's fees are still lower than the average small
cap mutual fund and average general equity mutual fund.
. The adjustment in no way signals a change in Acorn's proven investment
approach. And, the fee increase will give WAM the resources to continue to
compete for top analytical talent.
. Acorn Fund remains a good investment.
9