<PAGE>
GT GLOBAL THEME FUNDS
SUPPLEMENT TO PROSPECTUS DATED MARCH 1, 1998
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THE FOLLOWING SUPPLEMENTS, AS APPLICABLE, THE DISCUSSION UNDER "INVESTMENT
OBJECTIVES AND POLICIES," "HOW TO INVEST," "MANAGEMENT" AND "OTHER INFORMATION"
WITH RESPECT TO G.T. INVESTMENT FUNDS, INC. (THE "COMPANY"), GLOBAL INVESTMENT
PORTFOLIO (THE "PORTFOLIO") AND EACH FUND:
On January 30, 1998, Liechtenstein Global Trust, AG ("LGT"), the indirect parent
organization of GT Global, Inc. and Chancellor LGT Asset Management, Inc.
("Chancellor LGT"), entered into an agreement with AMVESCAP PLC ("AMVESCAP")
pursuant to which AMVESCAP will acquire LGT's Asset Management Division, which
includes Chancellor LGT (the "Purchase"). AMVESCAP is a holding company formed
in 1997 by the merger of INVESCO PLC and A I M Management Group Inc.
Consummation of the purchase is subject to a number of contingencies, including
regulatory approvals. The transaction would constitute an assignment of, and
thereby result in the termination of, the Company's investment management
agreement with Chancellor LGT. Accordingly, the Portfolio's Board of Trustees
and the Company's Board of Directors has approved, subject to shareholder
approval, new investment management and administration agreements between A I M
Advisors, Inc. ("A I M"), a wholly-owned subsidiary of AMVESCAP, and the
Portfolio or Company, as applicable, and sub-advisory and sub-administration
agreements between A I M and Chancellor LGT, which will become a separate,
indirect wholly-owned subsidiary of AMVESCAP. Under the new agreements, A I M
would serve as investment manager and administrator and Chancellor LGT would
serve as investment sub-adviser and sub-administrator of the Portfolio or
Company, as applicable. In addition to shareholder approval, implementation of
the new investment advisory arrangements is contingent upon the consummation of
the Purchase.
The Board of Directors of the Company has also approved the following matters,
subject to shareholder approval:
1. The adoption of compensation-type Rule 12b-1 plans of distribution for each
Fund that would replace each Fund's current reimbursement-type Rule 12b-1
plans of distribution.
2. Amendments to the fundamental investment restrictions of each Fund.
3. The reorganization of the Company from a Maryland corporation into a
Delaware business trust.
In addition, the Board has approved new distribution agreements for the Funds
pursuant to which A I M Distributors, Inc. ("A I M Distributors"), a
wholly-owned subsidiary of A I M, would serve as each Fund's principal
underwriter. In connection with the appointment of A I M Distributors as each
Fund's principal underwriter, each Fund's Class A shares would be sold subject
to a sales charge determined in accordance with the following amended schedule:
<TABLE>
<CAPTION>
INVESTOR'S SALES CHARGE DEALER CONCESSION
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AMOUNT OF AS A PERCENTAGE OF AS A PERCENTAGE OF AS A PERCENTAGE OF
INVESTMENT IN THE PUBLIC THE NET AMOUNT THE PUBLIC
SINGLE TRANSACTION OFFERING PRICE INVESTED OFFERING PRICE
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<S> <C> <C> <C>
Less than $50,000............................... 4.75% 4.99% 4.00%
$50,000 but less than $100,000.................. 4.00 4.17 3.25
$100,000 but less than $250,000................. 3.75 3.90 3.00
$250,000 but less than $500,000................. 2.50 2.56 2.00
$500,000 but less than $1,000,000*.............. 2.00 2.04 1.60
</TABLE>
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* Purchases of $1,000,000 or more will be at net asset value, subject to a
contingent deferred sales charge of 1% if shares are redeemed prior to 18
months from the date such shares were purchased.
Implementation of the new distribution arrangements is contingent upon (1)
shareholder approval of the new investment advisory arrangements and the new
Rule 12b-1 plans; and (2) the consummation of the Purchase.
A special meeting of shareholders of the Company will be held on May 20, 1998 to
consider and vote on, among other proposals, the matters noted above that
require shareholder approvals. If the matters are approved by shareholders and
the Purchase consummated, it is anticipated that the changes described above
will become effective on or about June 1, 1998.
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THEST803M March 25, 1998
