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BARR ROSENBERG SERIES TRUST
Supplement dated April 20, 1998
to
Statement of Additional Information dated December 9, 1997
and Revised January 28, 1998
This Supplement is provided to update, and should be read in conjunction
with, the information provided in the Statement of Additional Information.
INVESTMENT RESTRICTIONS
1. The first investment restriction in the first paragraph of the section
entitled "Investment Restrictions" is revised to read in its entirety as
follows: "(1) Borrow money in excess of 10% of the value (taken at the
lower of cost or current value) of the Fund's total assets (not including
the amount borrowed) at the time the borrowing is made, and then only from
banks as a temporary measure to facilitate the meeting of redemption
requests (not for leverage) which might otherwise require the untimely
disposition of portfolio investments or for extraordinary or emergency
purposes or for payments of variation margin (in the case of the Barr
Rosenberg Double Alpha Market Fund only). Such borrowings will be repaid
before any additional investments are purchased. Short sales and related
borrowings of securities are not subject to this restriction."
2. The second paragraph of the section entitled "Investment Restrictions" is
revised to read in its entirety as follows: "Notwithstanding the latitude
permitted by Restriction 9 above, the Funds have no current intention of
purchasing interest rate futures."
