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MFS(R) Union Standard(R) Equity Fund
Supplement to Prospectus dated February 1, 1998
Effective October 8, 1998, MFS will terminate its contractual
relationships with American Capital Strategies, Ltd. ("ACS"). ACS was retained
to perform three functions: to develop and maintain the Labor Sensitivity Index
("LSI"), a common stock index comprised of companies selected on the basis of
labor sensitivity criteria; to administer the affairs of the Labor Advisory
Board ("LAB"), which is comprised of senior labor officials, senior managers of
companies with significant labor contracts, academics and other national labor
leaders or experts; and to vote proxies of companies included in the Fund's
portfolio.
MFS is seeking to retain another organization to screen companies based
on labor sensitivity criteria for the Fund. The LAB has expressed its
willingness to associate itself with another organization and to provide that
organization with substantially the same services it has provided to ACS (i.e.,
to assist in developing and applying labor screening criteria). Following the
termination of MFS' arrangement with ACS, MFS and the Fund will have no further
access to, and will not have the right to use, the LSI. The Fund will continue
to invest, under normal market conditions, not less than 65% of its total assets
in equity securities of companies that are presently contained in the LSI until
a new arrangement with a new organization is in place. After the new arrangement
is in place, the Fund intends to invest, under normal market conditions, not
less than 65% of its total assets in equity securities of companies that are on
an "approved list," provided to MFS by the newly engaged organization, which,
with the assistance and guidance of the LAB, will screen companies for inclusion
on this list.
MFS has retained JMR/Financial, Inc. to vote proxies of companies
included in the Fund's portfolio effective October 8, 1998. JMR/Financial, Inc.
is an investment adviser registered with the Securities and Exchange Commission,
and will provide substantially the same proxy voting services as provided by
ACS.
The date of this Supplement is October 2, 1998.
