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MFS(R) MID CAP VALUE FUND
Supplement to the Current Prospectus
Effective May 1, 2000, the Principal Investment Policies of the Fund are
hereby restated as follows:
The fund invests, under normal market conditions, at least 65% of its total
assets in common stocks and related securities, such as preferred stocks,
convertible securities and depositary receipts for those securities, of
companies with medium market capitalizations which MFS believes are undervalued
in the market relative to their long term potential.
Medium market capitalization companies are defined by the fund as companies
with market capitalizations equaling or exceeding $250 million but not exceeding
the top of the Russell MidcapTM Growth Index range at the time of the fund's
investment. This Index is a widely recognized, unmanaged index of mid-cap common
stock prices. Companies whose market capitalizations fall below $250 million or
exceed the top of the Russell Midcap TM Growth Index range after purchase
continue to be considered medium-capitalization companies for purposes of the
fund's 65% investment policy. As of March 31, 1999, the top of the Russell
Midcap TM Growth Index range was $31 billion. The fund's investments may include
securities listed on a securities exchange or traded in the over-the-counter
markets.
MFS uses a bottom-up, as opposed to a top-down, investment style in
managing the equity-oriented funds (such as the fund) it advises. This means
that securities are selected based upon fundamental analysis performed by the
fund's portfolio manager and MFS' large group of equity research analysts.
Consistent with its principal investment strategies described above, the
fund may invest in foreign securities (including emerging markets securities),
through which it may have exposure to foreign currencies.
The date of this supplement is May 1, 2000.
