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VERTEX(SM) INCOME FUND
Supplement to the Current Prospectus
Effective June 30, 2000, the Expense Summary section is hereby amended and
restated:
EXPENSE SUMMARY
Class A Class B Class C
Maximum Sales Charge (Load) Imposed on
Purchases (as a percentage of offering price).. 4.75% 0.00% 0.00%
Maximum Deferred Sales Charge (Load) (as a
percentage of original purchase price or
redemption proceeds, whichever is less)........ See Below(1) 4.00% 1.00%
Annual Fund Operating Expenses (expenses that are deducted from fund
assets):
Management Fees (2).............................. 2.00% 2.00% 2.00%
Distribution and Service (12b-1) Fees(3)......... 0.35% 1.00% 1.00%
Other Expenses................................... 3.78% 3.78% 3.78%
----- ----- -----
Total Annual Fund Operating Expenses............. 6.13% 6.78% 6.78%
Fee Waiver and/or Expense Reimbursement(4).. (6.09)% (5.74)% (5.74)%
------- ------- -------
Net Expenses(5) 0.04% 1.04% 1.04%
--------------------
(1) An initial sales charge will not be deducted from your purchase if you buy
$1 million or more of class A shares, or if you are investing through a
retirement plan and your class A purchase meets certain requirements.
However, in this case, a contingent deferred sales charge (referred to as a
CDSC) of 1% may be deducted from your redemption proceeds if you redeem
your investment within 12 months.
(2) The management fee is subject to performance adjustments as described under
"Management of the Funds - Investment Adviser."
(3) The fund adopted a distribution plan under Rule 12b-1 that permits it to
pay marketing and other fees to support the sale and distribution of class
A, B and C shares and the services provided to you by your financial
adviser (referred to as distribution and service fees).
(4) The adviser has contractually agreed to waive its right to receive the
management fee, and subject to reimbursement, to bear all of the fund's
"Other Expenses" after taking into account the expense offset arrangement
described below, and excluding expenses associated with the funds investing
activities (including interest and dividend expenses with respect to
securities sold short and borrowing activity). The Adviser will not be
reimbursed for bearing expenses up to an expense limitation amount of
2.00%, but will be entitled to reimbursement by the fund for expenses borne
above this amount. In addition, the fund's distributor MFS Fund
Distributors, Inc., has contractually agreed to waive the fund's class A
distribution and service fees. These contractual arrangements will continue
until at least May 1, 2001, unless changed with the consent of the board of
trustees which oversees the fund.
(5) The fund has an expense offset arrangement which reduces the fund's
custodian fee based upon the amount of cash maintained by the fund with its
custodian and dividend disbursing agent and the fund may enter into other
similar 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 estimated to be 0.00% for class A, 1.00%
for class B and 1.00% for class C shares.
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;
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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 1 Year 3 Years
Class A shares $479 $1,691
Class B shares:
Assuming redemption: $506 $1,791
Assuming no redemption: $106 $1,491
Class C shares:
Assuming redemption: $206 $1,491
Assuming no redemption: $106 $1,491
The date of this Supplement is July 28, 2000.
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VERTEX(SM) INCOME FUND
Supplement dated May 1, 2000 (as revised July 28, 2000)
to the Current Prospectus
This Supplement describes the fund's class I shares, and it supplements certain
information in the fund's Prospectus dated May 1, 2000. The caption headings
used in this Supplement correspond with the caption headings used in the
Prospectus.
You may purchase class I shares only if you are an eligible institutional
investor, as described under the caption "Description of Share Classes" below.
1. RISK RETURN SUMMARY
Performance Table. The "Performance Table" is not included because the fund
has not had a full calendar year of investment operations.
2. EXPENSE SUMMARY
Expense Table. The "Expense Table" describes the fees and expenses that you
may pay when you buy, redeem and hold shares of the fund. The table is
supplemented as follows:
Class I
Maximum Sales Charge (Load) Imposed on Purchases
(as a percentage of offering price)................... None
Maximum Deferred Sales Charge (Load) (as a
percentage of original purchase price or
redemption proceeds, whichever is less)............... None
Annual Fund Operating Expenses (expenses that are deducted from fund
assets):
Management Fees(1)................................. 2.00%
Distribution and Service (12b-1) Fees.............. 0.00%
Other Expenses..................................... 3.78%
-----
Total Annual Fund Operating Expenses............... 5.78%
Fee Waiver and/or Expense Reimbursement (2) .... (5.74)%
-------
Net Expenses (3)................................ 0.04%
--------------------------
(1) The management fee is subject to performance adjustments as described under
"Management of the Funds - Investment Adviser" in the prospectus.
(2) The adviser has contractually agreed to waive its right to receive the
management fee, and subject to reimbursement, to bear all of the fund's
"Other Expenses" after taking into account the expense offset arrangement
described below, and excluding expenses associated with the funds investing
activities (including interest and dividend expenses with respect to
securities sold short and borrowing activity). The Adviser will not be
reimbursed for bearing expenses up to an expense limitation amount of
2.00%, but will be entitled to reimbursement by the fund for expenses borne
above this amount. These contractual arrangements will continue until at
least May 1, 2001, unless changed with the consent of the board of trustees
which oversees the fund.
(3) The fund has an expense offset arrangement which 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. Had these expense reductions been taken into account, "Net
Expenses" would be estimated to be 0.00%.
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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.
These 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 Expense Summary table above).
The table is supplemented as follows:
Share Class Year 1 Year 3
----------- ------ ------
Class I shares $4 $1,208
3. DESCRIPTIONS OF SHARE CLASSES
The "Description of Share Classes" is supplemented as follows:
If you are an eligible institutional investor (as described below), you may
purchase class I shares at net asset value without an initial sales charge or
CDSC upon redemption. Class I shares do not have annual distribution and service
fees, and do not convert to any other class of shares of the fund.
The following eligible institutional investors may purchase class I shares:
o certain retirement plans established for the benefit of employees of
VIM, the Fund's investment adviser, Massachusetts Financial Services
Company ("MFS"), the corporate parent of Vertex, and employees of
MFS's affiliates;
o any fund distributed by MFS Fund Distributors, Inc., ('MFD"), if the
fund seeks to achieve its investment objective by investing primarily
in shares of the fund and other MFS fund's:
In no event will the fund, MFS, MFD or any of their affiliates pay any sales
commissions or compensation to any third party in connection with the sale of
class I shares. The payment of any such sales commission or compensation would,
under the fund's policies, disqualify the purchaser as an eligible investor in
class I shares.
4. HOW TO PURCHASE, EXCHANGE AND REDEEM SHARES
The discussion of "How to Purchase, Exchange and Redeem Shares" is supplemented
as follows:
You may purchase, redeem and exchange class I shares only through your MFD
representative or by contacting MFSC (see the back cover of the Prospectus for
address and phone number). You may exchange your class I shares for class I
shares of another MFS Fund (if you are eligible to purchase them) and for shares
of the MFS Money Market Fund at net asset value.
The date of this Supplement is May 1, 2000 (as revised July 28, 2000).
