<PAGE>
ST. CLAIR FUNDS, INC.
SUPPLEMENT DATED JULY 6, 1998
TO PROSPECTUS DATED MAY 1, 1998
MUNDER INSTITUTIONAL S&P 500 INDEX EQUITY FUND
MUNDER INSTITUTIONAL S&P MIDCAP INDEX EQUITY FUND
MUNDER INSTITUTIONAL S&P SMALLCAP INDEX EQUITY FUND
MUNDER INSTITUTIONAL SHORT TERM TREASURY FUND
MUNDER INSTITUTIONAL MONEY MARKET FUND
INVESTMENT ADVISOR
The first paragraph under "STRUCTURE AND MANAGEMENT OF THE FUNDS--Who Manages
and Services the Funds?--Investment Advisor" in the Prospectus is hereby deleted
in its entirety and supplemented as follows:
INVESTMENT ADVISOR. The Funds' investment advisor is Munder Capital
Management, a Delaware general partnership with its principal offices at 480
Pierce Street, Birmingham, Michigan 48009. The principal partners of the
Advisor are Old MCM, Inc. ("MCM"), Munder Group LLC and WAM Holdings, Inc.
("WAM"). MCM was founded in February 1985 as a Delaware corporation and was a
registered investment advisor. WAM is an indirect, wholly-owned subsidiary of
Comerica Incorporated which owns or controls approximately 88%
of the partnership interests in the Advisor. As of March 31, 1998, the Advisor
and its affiliates had approximately $50.5 billion in assets under management,
of which $25.4 billion were invested in equity securities, $10.7 billion were
invested in money market or other short-term instruments, $9.5 billion were
invested in other fixed income securities and $4.9 billion in non-discretionary
assets.
<PAGE>
ST. CLAIR FUNDS, INC.
SUPPLEMENT DATED JULY 6, 1998
TO PROSPECTUS DATED MAY 1, 1998
LIQUIDITY PLUS MONEY MARKET FUND
INVESTMENT ADVISOR
The first paragraph under "STRUCTURE AND MANAGEMENT OF THE FUND--Who Manages and
Services the Fund?--Investment Advisor" in the Prospectus is hereby deleted in
its entirety and supplemented as follows:
INVESTMENT ADVISOR. The Fund's investment advisor is Munder Capital
Management, a Delaware general partnership with its principal offices at 480
Pierce Street, Birmingham, Michigan 48009. The principal partners of the
Advisor are Old MCM, Inc. ("MCM"), Munder Group LLC and WAM Holdings, Inc.
("WAM"). MCM was founded in February 1985 as a Delaware corporation and was a
registered investment advisor. WAM is an indirect, wholly-owned subsidiary of
Comerica Incorporated which owns or controls approximately 88%
of the partnership interests in the Advisor. As of March 31, 1998, the Advisor
and its affiliates had approximately $50.5 billion in assets under management,
of which $25.4 billion were invested in equity securities, $10.7 billion were
invested in money market or other short-term instruments, $9.5 billion were
invested in other fixed income securities and $4.9 billion in non-discretionary
assets.
<PAGE>
ST. CLAIR FUNDS, INC.
SUPPLEMENT DATED JULY 6, 1998
TO STATEMENT OF ADDITIONAL INFORMATION DATED MAY 1, 1998
MUNDER INSTITUTIONAL S&P 500 INDEX EQUITY FUND
MUNDER INSTITUTIONAL S&P MIDCAP INDEX EQUITY FUND
MUNDER INSTITUTIONAL S&P SMALLCAP INDEX EQUITY FUND
MUNDER INSTITUTIONAL SHORT TERM TREASURY FUND
MUNDER INSTITUTIONAL MONEY MARKET FUND
INVESTMENT ADVISORY AGREEMENT
Effective July 2, 1998, the Funds have entered into a new Investment Advisory
Agreement (the "Agreement") with the Advisor pursuant to terms of an
Exemptive Order (the "Order") granted by the Securities and Exchange
Commission. Under the terms of the Order, the Agreement must be approved by
the shareholders within one hundred and fifty (150) days but no later than
November 30, 1998. The Funds will call a special meeting of the shareholders
to approve the Agreement. Until shareholder approval, the fees paid to the
Advisor will be paid into an escrow account. If the Agreement is not
approved by the shareholders, the Board of Directors will consider
appropriate action.
<PAGE>
ST. CLAIR FUNDS, INC.
SUPPLEMENT DATED JULY 6, 1998
TO STATEMENT OF ADDITIONAL INFORMATION DATED MAY 1, 1998
LIQUIDITY PLUS MONEY MARKET FUND
INVESTMENT ADVISORY AGREEMENT
Effective July 2, 1998, the Fund has entered into a new Investment Advisory
Agreement (the "Agreement") with the Advisor pursuant to terms of an
Exemptive Order (the "Order") granted by the Securities and Exchange
Commission. Under the terms of the Order, the Agreement must be approved by
the shareholders within one hundred and fifty (150) days but no later than
November 30, 1998. The Fund will call a special meeting of the shareholders
to approve the Agreement. Until shareholder approval, the fee paid to the
Advisor will be paid into an escrow account. If the Agreement is not
approved by the shareholders, the Board of Directors will consider
appropriate action.
