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VERTEX U.S. ALL CAP FUND
Supplement to the Current Prospectus
The Board of Trustees which oversees the Vertex U.S. All Cap Fund (the
"Fund"), has approved the termination of the Fund effective December 22, 1999,
or as soon thereafter as practicable (the "Termination Date"). In connection
with the termination of the Fund, the Board of Trustees has suspended the sale
of the Fund's shares effective immediately. Consequently, purchase orders for
Fund shares that are received on or after December 8, 1999 will be rejected by
the Fund.
Enclosed is a formal Notice of Termination which is designed to answer
any questions concerning the Fund's termination. As described more fully in this
Notice, until the Termination Date, shareholders may choose to redeem their Fund
shares or exchange their shares for shares of the same class of any fund in the
MFS Family of Funds(R) which permits exchanges at such fund's then current net
asset value. If a shareholder takes no action, his or her shares will
automatically be exchanged on the Termination Date for shares of the MFS(R)
Money Market Fund ("MMM").
MMM, a member of the MFS Family of Funds, seeks to provide as high a
level of current income as is consistent with the preservation of capital and
liquidity. MMM's prospectus is enclosed with the Notice of Termination.
THE DATE OF THIS SUPPLEMENT IS DECEMBER 8, 1999.
