<PAGE>
LIBERTY ACORN FUND
LIBERTY ACORN INTERNATIONAL
LIBERTY ACORN USA
LIBERTY ACORN TWENTY
LIBERTY ACORN FOREIGN FORTY
Supplement dated November 17, 2000
to Prospectus dated September 29, 2000 of Liberty Acorn Trust
LIBERTY ACORN FUND. The second sentence under the heading "Principal
Investment Strategies" on page 2 is deleted and replaced by the following
sentences: "The Fund generally invests in stocks of companies with market
capitalizations of less than $2 billion at the time of purchase. As long as a
stock continues to meet the Fund's other investment criteria, the Fund may
choose to hold the stock even if it grows beyond an arbitrary capitalization
limit."
LIBERTY ACORN INTERNATIONAL. The second sentence under the heading
"Principal Investment Strategies" on page 7 is deleted and replaced by the
following sentences: "The Fund generally invests in stocks of companies based
outside the U.S. with market capitalizations of less than $5 billion at the time
of purchase. As long as a stock continues to meet the Fund's other investment
criteria, the Fund may choose to hold the stock even if it grows beyond an
arbitrary capitalization limit."
LIBERTY ACORN USA. The second sentence under the heading "Principal
Investment Strategies" on page 12 is deleted and replaced by the following
sentences: "The Fund generally invests in the stocks of U.S. companies with
market capitalizations of less than $2 billion at the time of purchase. As long
as a stock continues to meet the Fund's other investment criteria, the Fund may
choose to hold the stock even if it grows beyond an arbitrary capitalization
limit."
LIBERTY ACORN FOREIGN FORTY. The third sentence under the heading
"Principal Investment Strategies" on page 20 is deleted and replaced by the
following sentences: "The Fund is a non-diversified Fund that takes advantage of
its advisor's research and stock-picking capabilities to invest in a limited
number of foreign companies (between 40-60), offering the potential to provide
above-average growth over time. The Fund invests primarily in companies with
market capitalizations of $5 to $15 billion at the time of purchase."
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LIBERTY ACORN FUND
Supplement dated November 17, 2000
to Prospectus dated September 29, 2000 of Liberty Acorn Fund
Class Z Shares
The second sentence under the heading "Principal Investment Strategies" on
page 2 is deleted and replaced by the following sentences: "The Fund generally
invests in stocks of companies with market capitalizations of less than $2
billion at the time of purchase. As long as a stock continues to meet the Fund's
other investment criteria, the Fund may choose to hold the stock even if it
grows beyond an arbitrary capitalization limit."
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LIBERTY ACORN INTERNATIONAL
Supplement dated November 17, 2000
to Prospectus dated September 29, 2000 of Liberty Acorn International
Class Z Shares
The second sentence under the heading "Principal Investment Strategies" on
page 2 is deleted and replaced by the following sentences: "The Fund generally
invests in stocks of companies based outside the U.S. with market
capitalizations of less than $5 billion at the time of purchase. As long as a
stock continues to meet the Fund's other investment criteria, the Fund may
choose to hold the stock even if it grows beyond an arbitrary capitalization
limit."
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LIBERTY ACORN USA
Supplement dated November 17, 2000
to Prospectus dated September 29, 2000 of Liberty Acorn USA
Class Z Shares
The second sentence under the heading "Principal Investment Strategies" on
page 2 is deleted and replaced by the following sentences: "The Fund generally
invests in the stocks of U.S. companies with market capitalizations of less than
$2 billion at the time of purchase. As long as a stock continues to meet the
Fund's other investment criteria, the Fund may choose to hold the stock even if
it grows beyond an arbitrary capitalization limit."
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LIBERTY ACORN FOREIGN FORTY
Supplement dated November 17, 2000
to Prospectus dated September 29, 2000 of Liberty Acorn Foreign Forty
Class Z Shares
The third sentence under the heading "Principal Investment Strategies" on
page 2 is deleted and replaced by the following sentences: "The Fund is a non-
diversified Fund that takes advantage of its advisor's research and stock-
picking capabilities to invest in a limited number of foreign companies (between
40-60), offering the potential to provide above-average growth over time. The
Fund invests primarily in companies with market capitalizations of $5 to $15
billion at the time of purchase."
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LIBERTY ACORN TWENTY
Supplement dated November 17, 2000
to Prospectus dated September 29, 2000 of Liberty Acorn Twenty
Class A, B, and C Shares
The first sentence of note (7) under the heading "Annual Fund Operating
Expenses (deducted directly from fund assets)" on page 5 is deleted and replaced
by the following sentence: "The Fund's Advisor has voluntarily agreed to
reimburse the Fund for any ordinary operating expenses (exclusive of
distribution and service fees, interest, taxes and extraordinary expenses, if
any) exceeding 1.35% of the average annual net assets for Class A, Class B, and
Class C shares."
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LIBERTY ACORN FOREIGN FORTY
Supplement dated November 17, 2000
to Prospectus dated September 29, 2000 of Liberty Acorn Foreign Forty
Class A, B, and C Shares
The third sentence under the heading "Principal Investment Strategies" on
page 2 is deleted and replaced by the following sentences: "The Fund is a non-
diversified Fund that takes advantage of its advisor's research and stock-
picking capabilities to invest in a limited number of foreign companies (between
40-60), offering the potential to provide above-average growth over time. The
Fund invests primarily in companies with market capitalizations of $5 to $15
billion at the time of purchase."
The first sentence of note (8) under the heading "Annual Fund Operating
Expenses (deducted directly from fund assets)" on page 7 is deleted and replaced
by the following sentence: "The Fund's Advisor has voluntarily agreed to
reimburse the Fund for any ordinary operating expenses (exclusive of
distribution and service fees, interest, taxes and extraordinary expenses, if
any) exceeding 1.45% of the average annual net assets for Class A, Class B, and
Class C shares."
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LIBERTY ACORN FUND
Supplement dated November 17, 2000
to Prospectus dated September 29, 2000 of Liberty Acorn Fund
Class A, B, and C Shares
The second sentence under the heading "Principal Investment Strategies" on
page 2 is deleted and replaced by the following sentences: "The Fund generally
invests in stocks of companies with market capitalizations of less than $2
billion at the time of purchase. As long as a stock continues to meet the Fund's
other investment criteria, the Fund may choose to hold the stock even if it
grows beyond an arbitrary capitalization limit."
<PAGE>
LIBERTY ACORN INTERNATIONAL
Supplement dated November 17, 2000
to Prospectus dated September 29, 2000 of Liberty Acorn International
Class A, B, and C Shares
The second sentence under the heading "Principal Investment Strategies" on
page 2 is deleted and replaced by the following sentences: "The Fund generally
invests in stocks of companies based outside the U.S. with market
capitalizations of less than $5 billion at the time of purchase. As long as a
stock continues to meet the Fund's other investment criteria, the Fund may
choose to hold the stock even if it grows beyond an arbitrary capitalization
limit."
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LIBERTY ACORN USA
Supplement dated November 17, 2000
to Prospectus dated September 29, 2000 of Liberty Acorn USA
Class A, B and C Shares
The second sentence under the heading "Principal Investment Strategies" on
page 2 is deleted and replaced by the following sentences: "The Fund generally
invests in the stocks of U.S. companies with market capitalizations of less than
$2 billion at the time of purchase. As long as a stock continues to meet the
Fund's other investment criteria, the Fund may choose to hold the stock even if
it grows beyond an arbitrary capitalization limit."
