<PAGE>
MFS(R) BLUE CHIP FUND
Supplement to the Current Prospectus
The Board of Trustees responsible for overseeing MFS Blue Chip Fund
(the "Fund") is expected to consider at its next regular meeting on December 8,
1999, a proposal to terminate and liquidate the Fund, effective December 22,
1999, or as soon thereafter as is practicable (the "Termination Date"). If the
proposal is approved by the Board, sales of shares of the Fund will be suspended
and any shareholder who has not redeemed or exchanged all shares in his or her
account by the Termination Date will have his or her shares automatically
exchanged on the Termination Date for shares of MFS Money Market Fund.
The Date of this Supplement is November 24, 1999.
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MFS(R) CONVERTIBLE SECURITIES FUND
Supplement to the Current Prospectus
The Board of Trustees responsible for overseeing MFS Convertible
Securities Fund (the "Fund") is expected to consider at its next regular meeting
on December 8, 1999, a proposal to terminate and liquidate the Fund, effective
December 22, 1999, or as soon thereafter as is practicable (the "Termination
Date"). If the proposal is approved by the Board, sales of shares of the Fund
will be suspended and any shareholder who has not redeemed or exchanged all
shares in his or her account by the Termination Date will have his or her shares
automatically exchanged on the Termination Date for shares of MFS Money Market
Fund.
THE DATE OF THIS SUPPLEMENT IS NOVEMBER 24, 1999.
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MFS(R) SMALL CAP VALUE FUND
Supplement to the Current Prospectus
The Board of Trustees responsible for overseeing MFS Small Cap Value
Fund (the "Fund") is expected to consider at its next regular meeting on
December 15, 1999, a proposal to terminate and liquidate the Fund, effective
December 22, 1999, or as soon thereafter as is practicable (the "Termination
Date"). If the proposal is approved by the Board, sales of shares of the Fund
will be suspended and any shareholder who has not redeemed or exchanged all
shares in his or her account by the Termination Date will have his or her shares
automatically exchanged on the Termination Date for shares of MFS Money Market
Fund.
The Date of this Supplement is November 24, 1999.
<PAGE>
VERTEX U.S. ALL CAP FUND
Supplement to the Current Prospectus
The Board of Trustees responsible for overseeing Vertex U.S. All Cap
Fund (the "Fund") is considering a proposal to terminate and liquidate the Fund,
effective December 22, 1999, or as soon thereafter as is practicable (the
"Termination Date"). If the proposal is approved by the Board, sales of shares
of the Fund will be suspended and any shareholder who has not redeemed or
exchanged all shares in his or her account by the Termination Date will have his
or her shares automatically exchanged on the Termination Date for shares of MFS
Money Market Fund.
THE DATE OF THIS SUPPLEMENT IS NOVEMBER 24, 1999.
