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MFS(R) RESEARCH FUND
SUPPLEMENT TO THE CURRENT PROSPECTUS
Shareholders of the fund have been asked to vote to approve a new investment
advisory agreement with MFS Investment Management ("MFS") providing for an
increase in the investment management fee paid by the fund to MFS (the "New
Agreement").
Under the terms of the New Agreement, the gross income portion of the investment
management fee would be eliminated and the asset-based component of the fee
would be increased to 0.43% of the average daily net assets. This fee change is
the only material difference between the current Investment Advisory Agreement
described in the prospectus under "Management of the Fund-Investment Adviser"
(the "Current Agreement") and the New Agreement.
The New Agreement was unanimously approved by the fund's Board of Trustees and
will take effect on November 1, 1998 if approved by shareholders of record as of
August 24, 1998 at a special shareholders meeting to be held on October 15,
1998. If the New Agreement is not approved by shareholders the Current Agreement
will continue in effect.
The date of this Supplement is September 10, 1998.
