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SUPPLEMENT TO PROSPECTUS
DATED DECEMBER 14, 1999
67,602 SHARES OF KEYSTONE PROPERTY TRUST
COMMON STOCK $0.001 PAR VALUE
REGISTRATION NO. 333-92741
An aggregate of 67,602 shares of the Company's Common Stock were sold
on January 19, 2000 at a price of $15.49 per share by MPSN, LLC (The "selling
security holder").
All of the 67,602 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 19, 2000
