<PAGE>
MAS Funds
Supplement dated June 21, 1999 to the MAS Funds' Adviser Class Prospectus
dated January 31, 1999, as revised March 24, 1999.
This supplement supersedes and replaces any existing supplements to the
Prospectus. This supplement provides new and additional information beyond that
contained in the Prospectus and should be read in conjunction with the
Prospectus.
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At a meeting on May 27, 1999, the Board of Trustees approved a proposal to
increase the investment advisory fee for the High Yield Portfolio (the
"Portfolio") from 0.375% to 0.450%. This proposal will be submitted to the
Portfolio's shareholders of record as of June 18, 1999, to be voted upon at a
special shareholders' meeting scheduled to take place on September 16, 1999.
The proposal to increase the investment advisory fee will not be implemented
unless it receives shareholder approval.
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PORTFOLIO MANAGEMENT TEAM CHANGES
Page 11 of the Prospectus is hereby amended to include Gordon W. Loery as a
member of the portfolio management team of the High Yield Portfolio.
Page 15 of the Prospectus is hereby amended to include the following
description of Gordon W. Loery's business experience during the last five years:
Gordon W. Loery, Principal, MSDW, joined MAS in 1996. He served as a Fixed
Income Analyst at Morgan Stanley Asset Management Inc. from 1990 to 1996. He
joined the management team for the High Yield Portfolio in 1999.
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Page 3 of the Prospectus is hereby amended to include Steven B. Chulik as a
member of the portfolio management team for the Mid Cap Growth Portfolio.
Page 29 of the Prospectus is hereby amended to include Steven B. Chulik's
business experience during the last five years:
Steven B.Chulik joined MAS in 1997. He served as a Quantitative Hedge Fund
Analyst at IBJ Schroder Bank and Trust from 1994 to 1995. He attended the
Wharton School of the University of Pennsylvania from 1995 to 1997 and received
his MBA in 1997. He served as an Equity Analyst at MAS from 1997 to 1999. He
joined the management team for the Mid Cap Growth and Small Cap Growth
Portfolios in 1999.
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Due to other responsibilities within the firm, Ann D. Thivierge has
resigned from her position as a member of the portfolio management team of the
Multi-Asset-Class Portfolio. Therefore, pages 15 and 30 of the Prospectus are
hereby amended to reflect this change.
PLEASE RETAIN FOR FUTURE REFERENCE
<PAGE>
MAS Funds
Supplement dated June 21, 1999 to the MAS Funds' Institutional Class Prospectus
dated January 31, 1999, as revised April 30, 1999.
This supplement provides new and additional information beyond that contained in
the Prospectus and should be read in conjunction with the Prospectus.
- --------------------------------------------------------------------------------
At a meeting on May 27, 1999, the Board of Trustees approved a proposal to
increase the investment advisory fee for the High Yield Portfolio (the
"Portfolio") from 0.375% to 0.450%. This proposal will be submitted to the
Portfolio's shareholders of record as of June 18, 1999, to be voted upon at a
special shareholders' meeting scheduled to take place on September 16, 1999.
The proposal to increase the investment advisory fee will not be implemented
unless it receives shareholder approval.
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PORTFOLIO MANAGEMENT TEAM CHANGES
Pages 3 and 5 of the Prospectus are hereby amended to include Steven B.
Chulik as a member of the portfolio management team for the Mid Cap Growth and
Small Cap Growth Portfolios.
Page 39 of the Prospectus is hereby amended to include Steven B. Chulik's
business experience during the last five years:
Steven B. Chulik joined MAS in 1997. He served as a Quantitative Hedge Fund
Analyst at IBJ Schroder Bank and Trust from 1994 to 1995. He attended the
Wharton School of the University of Pennsylvania from 1995 to 1997 and received
his MBA in 1997. He served as an Equity Analyst at MAS from 1997 to 1999. He
joined the management team for the Mid Cap Growth and Small Cap Growth
Portfolios in 1999.
PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE
<PAGE>
MAS Funds
Supplement dated June 21, 1999 to the MAS Funds' Investment Class Prospectus
dated January 31, 1999, as revised April 30, 1999.
This supplement provides new and additional information beyond that contained in
the Prospectus and should be read in conjunction with the Prospectus.
- --------------------------------------------------------------------------------
At a meeting on May 27, 1999, the Board of Trustees approved a proposal to
increase the investment advisory fee for the High Yield Portfolio (the
"Portfolio") from 0.375% to 0.450%. This proposal will be submitted to the
Portfolio's shareholders of record as of June 18, 1999, to be voted upon at a
special shareholders' meeting scheduled to take place on September 16, 1999.
The proposal to increase the investment advisory fee will not be implemented
unless it receives shareholder approval.
PLEASE RETAIN THIS SUPPLEMENT FOR FUTURE REFERENCE
