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                                                                     EXHIBIT 3.k



                             KEYSTONE PROPERTY TRUST

                            CERTIFICATE OF CORRECTION
                                       TO
                             "DECLARATION OF TRUST"


      KEYSTONE PROPERTY TRUST, a Maryland real estate investment trust (the
"TRUST"), having its principal office in Baltimore City, Maryland, hereby
certifies to the State Department of Assessments and Taxation of Maryland (the
"MSDAT") that:

      FIRST: The Declaration of Trust of the Trust, dated April 30, 1999, was
filed with the MSDAT on April 30, 1999 at 1:55 p.m., and said Declaration of
Trust requires correction as permitted by Section 1-207 of the Corporation and
Associations Article of the Annotated Code of Maryland.

      SECOND: Section 1.2 of ARTICLE I of the said Declaration of Trust, as
previously filed and to be corrected hereby reads as follows:

      1.2. PLACES OF BUSINESS. THE TRUST SHALL MAINTAIN AN OFFICE IN MARYLAND AT
C/O THE CSC-LAWYERS INCORPORATING SERVICE COMPANY MARYLAND, 11 EAST CHASE
STREET, BALTIMORE, MARYLAND 21202 OR SUCH OTHER PLACE IN MARYLAND AS THE
TRUSTEES MAY DETERMINE FROM TIME TO TIME. THE RESIDENT AGENT OF THE TRUST AT
SUCH OFFICE SHALL BE THE PRENTICE-HALL COMPANY SYSTEM, MARYLAND, 11 EAST CHASE
STREET, BALTIMORE, MARYLAND 21202. THE RESIDENT AGENT IS A MARYLAND CORPORATION.
THE TRUST MAY CHANGE SUCH RESIDENT AGENT FROM TIME TO TIME AS THE TRUSTEES SHALL
DETERMINE. THE TRUST MAY HAVE SUCH OTHER OFFICES OR PLACES OF BUSINESS WITHIN OR
WITHOUT THE STATE OF MARYLAND AS THE TRUSTEES MAY FROM TIME TO TIME DETERMINE.

      THIRD: Section 1.2 of ARTICLE I of the said Declaration of Trust, as
corrected hereby is as follows:

      1.2. PLACES OF BUSINESS. THE TRUST SHALL MAINTAIN AN OFFICE IN MARYLAND AT
C/O CSC-LAWYERS INCORPORATING SERVICE COMPANY, 11 EAST CHASE STREET, BALTIMORE,
MARYLAND 21202 OR SUCH OTHER PLACE IN MARYLAND AS THE TRUSTEES MAY DETERMINE
FROM TIME TO TIME. THE RESIDENT AGENT OF THE TRUST AT SUCH OFFICE SHALL BE
CSC-LAWYERS INCORPORATING SERVICE COMPANY, 11 EAST CHASE STREET, BALTIMORE,
MARYLAND 21202. THE RESIDENT AGENT IS A MARYLAND CORPORATION. THE TRUST MAY
CHANGE SUCH RESIDENT AGENT FROM TIME TO TIME AS THE TRUSTEES SHALL DETERMINE.
THE TRUST MAY HAVE SUCH OTHER OFFICES OR PLACES OF BUSINESS WITHIN OR WITHOUT
THE STATE OF MARYLAND AS THE TRUSTEES MAY FROM TIME TO TIME DETERMINE.


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      FOURTH: The inaccuracy or defect contained in Section 1.2 of ARTICLE I of
the said Declaration of Trust, as previously filed is an error in transcription
of the address of the principal office.

      FIFTH: The legend in Section 4.14(a)(9) of ARTICLE IV of the said
Declaration of Trust, as previously filed and to be corrected hereby reads as
follows:

      THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO RESTRICTIONS
      ON BENEFICIAL AND CONSTRUCTIVE OWNERSHIP AND TRANSFER FOR THE PURPOSE OF
      THE TRUST'S MAINTENANCE OF ITS STATUS AS A REAL ESTATE INVESTMENT TRUST
      UNDER THE INTERNAL REVENUE CODE OF 1986, AS AMENDED (THE "CODE"). SUBJECT
      TO CERTAIN FURTHER RESTRICTIONS AND EXCEPT AS EXPRESSLY PROVIDED IN THE
      TRUST'S DECLARATION OF TRUST, (I) NO PERSON MAY BENEFICIALLY OR
      CONSTRUCTIVELY OWN COMMON SHARES OF THE TRUST IN EXCESS OF 4.9% (IN VALUE
      OR NUMBER OF SHARES) OF THE OUTSTANDING COMMON SHARES OF THE TRUST UNLESS
      SUCH PERSON IS AN EXCEPTED HOLDER (IN WHICH CASE THE EXCEPTED HOLDER
      OWNERSHIP LIMIT SHALL BE APPLICABLE); (II) NO PERSON MAY BENEFICIALLY OR
      CONSTRUCTIVELY OWN SHARES OF THE TRUST IN EXCESS OF 9.9% IN VALUE OF
      NUMBER OF SHARES OF THE OUTSTANDING SHARES OF ANY CLASS OR SERIES OF
      PREFERRED STOCK THE TRUST, UNLESS SUCH PERSON IS AN EXCEPTED HOLDER (IN
      WHICH CASE THE EXCEPTED HOLDER OWNERSHIP LIMIT SHALL BE APPLICABLE); (III)
      NO PERSON MAY BENEFICIALLY OR CONSTRUCTIVELY OWN SHARES THAT WOULD RESULT
      IN THE TRUST BEING "CLOSELY HELD" UNDER SECTION 856(H) OF THE CODE OR
      OTHERWISE CAUSE THE TRUST TO FAIL TO QUALIFY AS A REIT; (IV) NO PERSON MAY
      TRANSFER SHARES IF SUCH TRANSFER WOULD RESULT IN THE SHARES OF THE TRUST
      BEING OWNED BY FEWER THAN 100 PERSONS; (V) NO PERSON MAY TRANSFER SHARES
      IF SUCH TRANSFER WOULD RESULT IN SHARES OF THE TRUST BEING OWNED BY A
      DISQUALIFIED PERSON; AND (VI) NO PLANS AND CERTAIN OTHER PERSONS DESCRIBED
      IN OR SUBJECT TO THE PLAN ASSET REGULATIONS MAY OWN MORE THAN 24.9% OF THE
      VALUE OF ANY CLASS OF SHARES OF THE TRUST. ANY PERSON WHO BENEFICIALLY OR
      CONSTRUCTIVELY OWNS OR ATTEMPTS TO BENEFICIALLY OR CONSTRUCTIVELY OWN
      SHARES WHICH CAUSES OR WILL CAUSE A PERSON TO BENEFICIALLY OR
      CONSTRUCTIVELY OWN SHARES IN EXCESS OR IN VIOLATION OF THE ABOVE
      LIMITATIONS MUST IMMEDIATELY NOTIFY THE TRUST. IF ANY OF THE RESTRICTIONS
      ON TRANSFER OR OWNERSHIP ARE VIOLATED, THE SHARES REPRESENTED HEREBY MAY
      BE AUTOMATICALLY TRANSFERRED TO A CHARITABLE TRUSTEE OF A CHARITABLE TRUST
      FOR THE BENEFIT OR ONE OR MORE CHARITABLE BENEFICIARIES. IN ADDITION, UPON
      THE OCCURRENCE OF CERTAIN EVENTS, ATTEMPTED TRANSFERS IN VIOLATION OF THE
      RESTRICTIONS DESCRIBED ABOVE MAY BE VOID AB INITIO. ALL CAPITALIZED TERMS
      IN THIS LEGEND HAVE THE MEANINGS DEFINED IN THE DECLARATION OF TRUST, AS
      THE SAME MAY BE AMENDED FROM TIME TO TIME, A COPY OF WHICH, INCLUDING THE
      RESTRICTIONS ON TRANSFER AND OWNERSHIP, WILL BE FURNISHED TO EACH HOLDER
      OF SHARES OF THE TRUST ON REQUEST AND WITHOUT CHARGE.


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      SIXTH: The legend in Section 4.14(a)(9) of ARTICLE IV of the said
Declaration of Trust, as corrected hereby is as follows:

      THE SECURITIES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO RESTRICTIONS
      ON BENEFICIAL AND CONSTRUCTIVE OWNERSHIP AND TRANSFER FOR THE PURPOSE OF
      THE TRUST'S MAINTENANCE OF ITS STATUS AS A REAL ESTATE INVESTMENT TRUST
      UNDER THE INTERNAL REVENUE CODE OF 1986, AS AMENDED (THE "CODE"). SUBJECT
      TO CERTAIN FURTHER RESTRICTIONS AND EXCEPT AS EXPRESSLY PROVIDED IN THE
      TRUST'S DECLARATION OF TRUST, (I) NO PERSON MAY BENEFICIALLY OR
      CONSTRUCTIVELY OWN COMMON SHARES OF THE TRUST IN EXCESS OF 4.9% (IN VALUE
      OR NUMBER OF SHARES) OF THE OUTSTANDING COMMON SHARES OF THE TRUST UNLESS
      SUCH PERSON IS AN EXCEPTED HOLDER (IN WHICH CASE THE EXCEPTED HOLDER
      OWNERSHIP LIMIT SHALL BE APPLICABLE); (II) NO PERSON MAY BENEFICIALLY OR
      CONSTRUCTIVELY OWN SHARES OF THE TRUST IN EXCESS OF 9.9% (IN VALUE OR
      NUMBER OF SHARES) OF THE OUTSTANDING SHARES OF ANY CLASS OR SERIES OF
      PREFERRED STOCK OF THE TRUST, UNLESS SUCH PERSON IS AN EXCEPTED HOLDER (IN
      WHICH CASE THE EXCEPTED HOLDER OWNERSHIP LIMIT SHALL BE APPLICABLE); (III)
      NO PERSON MAY BENEFICIALLY OR CONSTRUCTIVELY OWN SHARES THAT WOULD RESULT
      IN THE TRUST BEING "CLOSELY HELD" UNDER SECTION 856(H) OF THE CODE OR
      OTHERWISE CAUSE THE TRUST TO FAIL TO QUALIFY AS A REIT; (IV) NO PERSON MAY
      TRANSFER SHARES IF SUCH TRANSFER WOULD RESULT IN THE SHARES OF THE TRUST
      BEING OWNED BY FEWER THAN 100 PERSONS; (V) NO PERSON MAY TRANSFER SHARES
      IF SUCH TRANSFER WOULD RESULT IN SHARES OF THE TRUST BEING OWNED BY A
      DISQUALIFIED PERSON; AND (VI) NO PLANS AND CERTAIN OTHER PERSONS DESCRIBED
      IN OR SUBJECT TO THE PLAN ASSET REGULATIONS MAY OWN MORE THAN 24.9% OF THE
      VALUE OF ANY CLASS OF SHARES OF THE TRUST. ANY PERSON WHO BENEFICIALLY OR
      CONSTRUCTIVELY OWNS OR ATTEMPTS TO BENEFICIALLY OR CONSTRUCTIVELY OWN
      SHARES WHICH CAUSES OR WILL CAUSE A PERSON TO BENEFICIALLY OR
      CONSTRUCTIVELY OWN SHARES IN EXCESS OR IN VIOLATION OF THE ABOVE
      LIMITATIONS MUST IMMEDIATELY NOTIFY THE TRUST. IF ANY OF THE RESTRICTIONS
      ON TRANSFER OR OWNERSHIP ARE VIOLATED, THE SHARES REPRESENTED HEREBY MAY
      BE AUTOMATICALLY TRANSFERRED TO A CHARITABLE TRUSTEE OF A CHARITABLE TRUST
      FOR THE BENEFIT OR ONE OR MORE CHARITABLE BENEFICIARIES. IN ADDITION, UPON
      THE OCCURRENCE OF CERTAIN EVENTS, ATTEMPTED TRANSFERS IN VIOLATION OF THE
      RESTRICTIONS DESCRIBED ABOVE MAY BE VOID AB INITIO. ALL CAPITALIZED TERMS
      IN THIS LEGEND HAVE THE MEANINGS DEFINED IN THE DECLARATION OF TRUST, AS
      THE SAME MAY BE AMENDED FROM TIME TO TIME, A COPY OF WHICH, INCLUDING THE
      RESTRICTIONS ON TRANSFER AND OWNERSHIP, WILL BE FURNISHED TO EACH HOLDER
      OF SHARES OF THE TRUST ON REQUEST AND WITHOUT CHARGE.

      SEVENTH: The inaccuracy or defect contained in the legend in Section
4.14(a)(9) of ARTICLE IV of the said Declaration of Trust, as previously filed
is an error in transcription in clauses (II) and (V).


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      IN WITNESS WHEREOF, the undersigned have caused this Certificate of
Correction to be executed as of December 2, 1999. Each of the undersigned hereby
acknowledges that the foregoing Certificate of Correction is the act of said
Trustee and further certifies that, to the best of his knowledge, information
and belief, the matters and facts set forth herein are true in all material
respects, under the penalties of perjury.

WITNESS:



/s/ Stephen J. Butte                      /s/ Michael J. Falcone
------------------------------------      --------------------------------------
    Stephen J. Butte,                         Michael J. Falcone,
    Secretary                                 Trustee


                                          /s/ Francisco Galesi
                                          --------------------------------------
                                              Francisco Galesi,
                                              Trustee



                                          /s/ Jeffrey E. Kelter
                                          --------------------------------------
                                              Jeffrey E. Kelter,
                                              Trustee



                                          /s/ David H. Lesser
                                          --------------------------------------
                                              David H. Lesser,
                                              Trustee



                                          /s/ David F. Mcbride
                                          --------------------------------------
                                              David F. McBride,
                                              Trustee



                                          /s/ James Mulvihill
                                          --------------------------------------
                                              James Mulvihill,
                                              Trustee



                                          /s/ Russell C Platt
                                          --------------------------------------
                                              Russell C Platt,
                                              Trustee


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                                          /s/ Scott H. Reckler
                                          --------------------------------------
                                              Scott H. Reckler,
                                              Trustee



                                          /s/ Joseph D. Morris
                                          --------------------------------------
                                              Joseph D. Morris,
                                              Trustee


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