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MFS(R) INSTITUTIONAL TRUST
MFS(R) INSTITUTIONAL LARGE CAP GROWTH FUND
Supplement dated March 10, 2000 to the Current Prospectus
Effective March 1, 2000, the Expense Summary section is hereby amended and
restated to reflect a reduction in the management fee for the MFS Institutional
Large Cap Growth Fund (the "fund") from the current 75 basis points (0.75%) to
50 basis points (0.50%). The revised management fee for the fund is reflected
below in the Expense Table and Example of Expenses:
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):
Management Fees 0.75%
Distribution and Service (12b-1) Fees None
Other Expenses (1) 0.05%
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Total Annual Fund Operating Expenses 0.80%
Fee Waiver and/or Expense Reimbursement (1) (0.25)%
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Net Expenses(1) 0.55%
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(1) MFS has contractually agreed to reduce the management fee to a maximum of
0.50% annually of the average daily net assets of the fund. MFS has also
agreed to bear all of the fund's expenses, such that "Other Expenses" do
not exceed 0.05% annually. These contractual fee arrangements will remain
in effect until at least March 1, 2001, absent an earlier modification
approved by the board of trustees which oversees the 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
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).
Share Class Year 1 Year 3 Year 5 Year 10
Class A shares $56 $230 $420 $967
The date of this Supplement is March 10, 2000.
