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MFS INSTITUTIONAL CORE PLUS FIXED INCOME FUND
MFS INSTITUTIONAL RESEARCH FUND
MFS INSTITUTIONAL MID-CAP GROWTH EQUITY FUND
MFS INSTITUTIONAL INTERNATIONAL EQUITY FUND
Supplement to the December 1, 1995 Prospectus
Core Plus Research Mid-Cap International
EXPENSE SUMMARY Fund Fund Fund Equity Fund
Shareholder Transaction Expenses
Maximum Sales Load Imposed on
Purchases of Shares.......... None None None None
Maximum Sales Load Imposed on
Reinvested Dividends and
Distributions................ None None None None
Annual Operating Expenses (as a percentage of average net assets):
Management Fees................. 0.45% 0.60% 0.60% 0.75%
Other Expenses (after
applicable fee
reduction)(1)(2)............. 0.05% 0.05% 0.05% 0.10%
Total Operating Expenses
(after applicable fee
reduction)(2)................ 0.50% 0.65% 0.65% 0.85%
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(1) "Other Expenses" are based on estimates for each Fund's fiscal year
ending June 30, 1996.
(2) MFS has agreed to bear expenses of each Fund such that each Fund's
aggregate expenses do not exceed the following percentage, on an annualized
basis, of its average daily net assets: 0.50% of the Core Plus Fund, 0.65%
of the Research Fund, 0.65% of the Mid-Cap Fund and 0.85% of the
International Equity Fund. Each arrangement may be terminated or revised by
MFS at any time. See "Information Concerning Shares of the Funds -
Expenses" below. Absent these expense arrangements, estimated "Other
Expenses" and "Total Operating Expenses" for each respective Fund would be,
on an annualized basis, respectively, 3.63% and 4.08% of the Core Plus
Fund, respectively, 3.63% and 4.23% of the Research Fund, respectively,
3.63% and 4.23% of the Mid-Cap Fund, respectively, and 3.63% and 4.38% of
the International Equity Fund, respectively.
Example of Expenses
An investor would pay the following dollar amounts of expenses on a $1,000
investment in each Fund, assuming (a) a 5% annual return and (b) redemption at
the end of each of the time periods indicated:
Core Plus Research Mid-Cap International
Period Fund Fund Fund Equity Fund
1 year.......................... $ 5 $ 7 $ 7 $ 9
3 years......................... $16 $21 $21 $27
INFORMATION CONCERNING SHARES OF THE FUNDS - EXPENSES
The "Expense" section of the Prospectus with respect to the Core Plus Fund, the
Research Fund, the Mid-Cap Fund and the International Equity Fund, is amended as
follows:
MFS has also agreed, effective as of May 1, 1996, to pay the expenses of
each of the Core Plus Fund, the Research Fund, the Mid-Cap Fund and the
International Equity Fund such that the aggregate operating expenses of
each Fund do not exceed the following percentage, on an annualized basis,
of its average daily net assets: 0.50% of the Core Plus Fund, 0.65% of the
Research Fund, 0.65% of the Mid-Cap Fund and 0.85% of the International
Equity Fund. Each obligation to pay expenses may be terminated or revised
at any time by MFS without the consent of the Trust or the Fund by notice
in writing from MFS to the Trust on behalf of the Fund. The previous
expense reimbursement agreement is no longer in effect for these Funds.
The Date of this Supplement is May 22, 1996.
