<PAGE>
MFS(R) TECHNOLOGY FUND
Supplement to the Current Statement of Additional Information
During the period from May 1, 2000 through May 31, 2000, unless extended by
MFS Fund Distributors, Inc. ("MFD") (the "Sales Period"), MFD will pay FSC
Securities Corporation, HD Vest Investment Securities, Commonwealth Financial
Network, Cadaret Grant & Co. Inc., Nathan & Lewis Securities, Inc., First Union
Securities, Inc., JC Bradford & Co., AG Edwards & Sons, Inc., Stifel Nicolaus &
Company, Inc., US Bancorp Piper Jaffray, Inc., Nat City Investments Inc., Cuna
Brokerage Services, Inc., Centura Securities, Inc., UVEST Financial Services
Group, Inc., Invest, First Union Brokerage Services (the "Dealers") 100% of the
applicable sales charge on sales of Class A shares of the fund sold by the
Dealers during the Sales Period. In addition, MFD will pay the Dealers an
additional commission equal to 0.50% of the net asset value of all of the Class
B shares of the fund sold by the Dealers during the Sales Period.
The date of this Supplement is May 1, 2000.
<PAGE>
MFS(R) TECHNOLOGY FUND
Supplement to the Current Prospectus
During the period from May 1, 2000 through May 31, 2000 (unless extended by
MFS Fund Distributors, Inc. ("MFD")) (the "Sales Period"), MFD will pay Dain
Rauscher Incorporated 100% of the applicable sales charge on sales of Class A
shares of the fund sold by Dain Rauscher Incorporated during the Sales Period.
In addition, MFD will pay Dain Rauscher Incorporated an additional commission
equal to 0.50% of the net asset value of all of the Class B shares of the fund
sold by Dain Rauscher Incorporated during the Sales Period.
The date of this Supplement is May 1, 2000.