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MML SERIES INVESTMENT FUND
Supplement dated December 1, 1999
to the Prospectus dated May 3, 1999,
as previously supplemented June 4, 1999
The Prospectus is changed as follows:
1. The first full paragraph under the heading "Principal Investment
Strategies" for the MML Small Cap Value Equity Fund is deleted and the following
is substituted in its place:
The Fund invests primarily in stocks, securities convertible into
stocks and other securities, such as warrants and stock rights, whose
value is based on stock prices. The Fund generally invests in publicly
traded stocks of companies with market capitalizations in the range of
companies in the Russell 2000 Index (between approximately $5 million
and approximately $7.0 billion), the Fund's benchmark. Normally,
however, at least 65% of the Fund's investments will be in small cap
companies. For these purposes, the Fund treats as "small cap" those
companies with market capitalizations of up to $1.5 billion at the time
of purchase. However, the Fund will not automatically sell or cease to
purchase the stock of a company it already owns just because the
company's market capitalization grows or falls outside the range of
companies in the Russell 2000 Index.
2. The portfolio manager of the MML Small Cap Value Equity Fund changed on
December 1, 1999. The description of the former portfolio manager is deleted and
the following is substituted in its place:
Paul S. Szczygiel is the person principally responsible for the
day-to-day management of the MML Small Cap Value Equity Fund since
December 1, 1999. Prior to assuming day-to-day responsibility for
managing the Fund, Mr. Szczygiel was actively involved in assisting the
previous portfolio manager. Mr. Szczygiel also currently serves as
portfolio manager for several other registered and unregistered funds
sponsored by David L. Babson with similar investment objectives to the
Fund. Mr. Szczygiel is a Chartered Financial Analyst with over 14 years
of investment experience, and has been associated with the MassMutual
organization since 1994, prior to which he was an Associate Director at
Bear Stearns. Mr. Szczygiel is assisted in the day-to-day management of
the Fund by a team of Babson investment professionals.
December 1, 1999
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MML Series Investment Fund
Supplement dated December 1, 1999
to the Statement of Additional Information dated May 3, 1999
as previously supplemented June 11, 1999
and November 3, 1999
The Statement of Additional Information is changed as follows:
1. The first full paragraph under the heading "E. MML Small Cap Value
Equity" on page B-8 of the Statement of Additional Information is deleted and in
its place is substituted the following:
The Fund's current non-fundamental policy is that, under normal
circumstances, at least 65% of the value of its total assets will be
invested (determined at the time the Fund invests its assets) in equity
securities which are issued by companies with market capitalization, at
the time of purchase, of $1.5 billion or less. The Fund is not,
however, required to sell portfolio securities as a result of an
issuer's market capitalization increasing over $1.5 billion.
Consequently, during periods of equity market strength, a substantial
portion of the Fund's portfolio may consist of securities issued by
companies with a market capitalization in excess of $1.5 billion. The
Fund may purchase securities with above-average volatility relative to
indices like the S&P 500 Stock Index. While such volatility frequently
may involve the opportunity for greater gain, it also generally
involves greater risk of loss and, as a result, the Fund's shares are
suitable only for those investors who are in a financial position to
assume such risk.
December 1, 1999
