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SUPPLEMENT TO PROSPECTUS
DATED OCTOBER 15, 1999
41,300 COMMON SHARES OF KEYSTONE PROPERTY TRUST
$0.001 PAR VALUE
REGISTRATION NO. 333-89095
An aggregate of 41,300 of the Company's Common Shares were sold
on March 28, 2000 at a price of $12.6875 per share by CRA Real Estate
Securities, L.P. (the "selling security holder"), in nominee name of Hare &
Company.
All of the 41,300 shares of Common Stock described above were sold by
the selling security holder. The selling security holder has resold or will
resell such shares in the manner described under the "Method of Sale' section in
the Prospectus of which this Supplement forms a part. Any compensation in the
form of discounts, fees or commissions and any profits on the sales of such
shares may be deemed underwriting discounts or commissions.
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The date of this Prospectus Supplement is March 29, 2000
