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SUPPLEMENT TO PROSPECTUS
DATED OCTOBER 15, 1999
135,400 SHARES OF KEYSTONE PROPERTY TRUST
COMMON STOCK $0.001 PAR VALUE
REGISTRATION NO. 333-89095
An aggregate of 135,400 shares of the Company's Common Stock were sold
on January 13, 2000 at a price of $14.875 per share by CRA Real Estate
Securities (The "selling security holder"), in its capacity as investment
advisor, as follows: 87,400 shares on behalf of BellSouth Corp., nominee name of
Marine Crew & Co.; 5,000 shares on behalf of CRA REIT Fund, nominee name of Hare
& Co.; and 43,000 shares on behalf of IBM Retirement Fund, nominee name of Kane
& Co.
All of the 135,400 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 January 13, 2000
