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MFS(R) INSTITUTIONAL TRUST
MFS(R) INSTITUTIONAL CORE EQUITY FUND
MFS(R) INSTITUTIONAL RESEARCH FUND
MFS(R) INSTITUTIONAL MID CAP GROWTH FUND
Supplement dated July 18, 2000 to the Current Prospectus
Effective July 1, 2000, the Expense Summary section for the above referenced
funds (each a "fund") is hereby amended and restated as follows:
EXPENSE SUMMARY
Expense Table. The "Expense Table" describes expenses you may pay when you
hold shares of the fund.
Annual Fund Operating Expenses (expenses that are deducted from fund
assets):
Core Equity Research Mid Cap
Fund Fund Growth Fund
Management Fees 0.60% 0.60% 0.60%
Distribution and Service (12b-1) Fees None None None
Other Expenses 0.44% 0.17% 0.15%
----- ----- -----
Total Annual Fund Operating Expenses 1.04% 0.77% 0.75%
Fee Waiver/Expense Reimbursement(1) (0.48)% (0.21)% (0.09)%
------- ------- -------
Net Expenses(2) 0.56% 0.56% 0.66%
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(1) MFS has contractually agreed to waive a portion of the management fee
paid by Core Equity Fund and Research Fund equal to 0.05% annually, and
MFS has also agreed to bear each such fund's "Other Expenses", after
giving effect to the expense offset arrangement described below. MFS has
contractually agreed to bear the Mid Cap Growth Fund's "Other Expenses",
after giving effect to the expense offset arrangement described below,
such that "Other Expenses" do not exceed 0.05% annually. These
contractual fee arrangements will remain in effect until at least July 1,
2001, absent an earlier modification approved by the board of trustees
which oversees each fund.
(2) Each fund has an expense offset arrangement that reduces the fund's
custodian fee based upon the amount of cash maintained by the fund with
its custodian and dividend disbursing agent, and may enter into other
such arrangements and directed brokerage arrangements (which would also
have the effect of reducing the fund's expenses). Any such fee reductions
are not reflected in the table. Had these fee reductions been taken into
account, "Net Expenses" would be lower for the funds, and would equal
0.55% for Core Equity Fund and Research Fund, and 0.65% for Mid Cap
Growth Fund.
Example of Expenses. The "Example of Expenses" table is intended to help you
compare the cost of investing in the fund with the cost of investing in other
mutual funds.
The examples assume that:
o You invest $10,000 in the fund for the time periods indicated and you
redeem your shares at the end of the time periods;
o Your investment has a 5% return each year and dividends and other
distributions are reinvested; and
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o The fund's operating expenses remain the same, except that the fund's
total operating expenses are assumed to be the fund's "Net Expenses"
for the first year, and the fund's "Total Annual Fund Operating
Expenses" for subsequent years (see the table above).
Series Year 1 Year 3 Year 5 Year 10
Core Equity Fund $57 $283 $527 $1,228
Research Fund $57 $225 $407 $ 935
Mid Cap Growth Fund $67 $231 $408 $ 922
The date of this Supplement is July 18, 2000.
