<PAGE>
As Filed Pursuant to Rule
424(b)(4) Reg No# 333-59251
SUPPLEMENT
TO
PROSPECTUS DATED NOVEMBER 4, 1999
14,100 SHARES OF
KEYSTONE PROPERTY TRUST
COMMON STOCK
$0.001 PAR VALUE
An aggregate 14,100 shares of the Company's Common Stock were
sold on November 29, 1999 at a price of $15.375 per share by the CRA Realty
Shares Portfolio (the "selling security holder") as indicated in the table
"Selling Security Holders" in this Supplement
All of the 14,100 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.
SELLING SECURITY HOLDERS
Sales of our Common Shares registered in the Prospectus must (i) be
accompanied by a copy of the Prospectus, together with the applicable prospectus
supplement or (ii) be effected through an exemption from registration, such as
pursuant to Rule 144 under the Securities Act.
The following table lists (i) the selling security holders who may
offer our Common Shares from time to time pursuant to the Prospectus, (ii) the
number of Common Shares of each selling security holder, the offer and sale of
which is to be registered on behalf of each selling security holder pursuant to
the Prospectus (the "Registered Shares"). We registered the Registered Shares in
order to permit secondary trading of the Registered Shares, and the selling
security holder may offer Registered Shares for resale from time to time. See
the section "Method of Sale" in the Prospectus.
<TABLE>
<CAPTION>
NAME SHARES OWNED AND WHICH MAY BE SOLD
<S> <C>
Morgan Stanley Real Estate
Special Situations, Inc.(1) 44,320
Morgan Stanley Real Estate Special Situations
Investors, L.P. (1) 17,013
The Morgan Stanley Real Estate Special Situations
Fund I, L.P. (1) 200,000
The Morgan Stanley Real Estate Special Situations
Fund II, L.P. (1) 266,667
Stichting Bedrijfspensioenfonds Voor De
Metaalnijverheid(1) 132,000
Stichting Pensioenfonds ABP(1) 198,000
MS Special Funds Pte Ltd(1) 132,000
BellSouth Corp.(2) 34,051
IBM Retirement Fund(2) 20,000
PA State Employees Retirement System(2) 23,000
TRW Investment Mgt.(2)(3) 25,000
</TABLE>
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(1) Morgan Stanley Asset Management inc. acts as investment advisor to the
accounts that beneficially own these Common Shares.
(2) CRA Real Estate Securities acts as investment advisor to the accounts that
beneficially own these Common Shares.
(3) TRW Investment Mgt. transferred all of it's 25,000 shares to CRA Realty
Shares Portfolio, in the nominee name Hare & Co. on December 29,1998. CRA Realty
Shares Portfolio is selling 14,100 of such shares pursuant to this Prospectus
Supplement.
<PAGE>
Each of the selling security holders purchased its Common Shares in a
private placement of securities on July 9, 1998. Under Registration Rights
Agreements, dated as of July 9, 1998, we agreed to register the Common Shares
which they purchased in the private placement and the selling security holders
agreed not to sell such shares for a period of one year from the date of such
Registration Rights Agreements.
Since the selling security holders may sell all, some or none of their
Common Shares, we cannot estimate the actual number of shares which will be
offered pursuant to this Prospectus.
We have agreed to indemnify the selling security holders against
certain liabilities. See "Method of Sale" in the Prospectus.
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The date of this Prospectus Supplement is November 29, 1999
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