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DFA INVESTMENT DIMENSIONS GROUP INC.
SUPPLEMENT DATED SEPTEMBER 30, 1997
TO THE PROSPECTUS DATED MARCH 28, 1997
U.S. 9-10 Small Company Portfolio
The Board of Directors of DFA Investment Dimensions Group Inc. has
approved changes to certain of the investment policies and limitations of the
U.S. 9-10 Small Company Portfolio (the "Portfolio") in order to permit the
Portfolio to invest substantially all of its assets in the U.S. 9-10 Small
Company Series (the "9-10 Series") of The DFA Investment Trust Company.
These changes are subject to approval by the shareholders of the Portfolio.
The 9-10 Series is an open-end, management investment company having the same
investment objective, policies and limitations as the Portfolio. The 9-10
Series will be managed in the same manner as the Portfolio is currently
managed. Dimensional Fund Advisors Inc., the current investment advisor of
the Portfolio, is the investment adviser of the 9-10 Series. If shareholders
of the Portfolio approve these changes, the Portfolio will seek to achieve its
investment objective by investing substantially all of its assets in the 9-10
Series on or about November 30, 1997.
The Board of Directors of the Fund has also approved revisions to
certain of the Portfolio's other investment limitations, including the
elimination of the Portfolio's restrictions on the purchasing or selling of
options, futures and options on futures and the selling of securities short.
At the present time, however, the Portfolio does not intend to engage in
these investment activities and, therefore, the elimination of these
restrictions is not expected to have a material impact upon the Portfolio's
continued operations. The Board of Directors also approved a revision to the
Portfolio's borrowing policy in order to increase the amount the Portfolio is
permitted to borrow. The revisions to the Portfolio's investment limitation
with respect to borrowing as approved by the Board of Directors permit the
Portfolio to borrow amounts not exceeding 33% of its net assets from banks
and pledge not more than 33% of such assets to secure such loans. The Board
of Directors of the Fund also approved a change to the Fund's current
investment limitations with respect to the diversification of its assets.
The revisions to the Portfolio's investment limitations in this regard as
approved by the Board of Directors provide that, as to 75% of the Portfolio's
assets, it will not invest in the securities of any issuer (except
obligations of the U.S. Government and its instrumentalities) if, as a
result, more than 5% of the Portfolio's total assets, at market, would be
invested in the securities of such issuer; and, as to 75% of the Portfolio's
assets, it will not acquire more than 10% of the voting securities of any
issuer. There is no present intention to modify the manner in which the
Portfolio is managed in light of these changes in the borrowing and
diversification policies of the Portfolio. All of the changes to the
investment limitations of the Portfolio as described above are subject to the
approval of the Portfolio's shareholders.
