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                                                                    EXHIBIT 3.3


                             BRANDYWINE REALTY TRUST
                              ARTICLES OF AMENDMENT

THIS IS TO CERTIFY THAT:

                  FIRST: The Declaration of Trust of Brandywine Realty Trust, a
Maryland real estate investment trust (the "Company"), is hereby amended by
deleting existing Sections 6.6(g) and 6.6(l) of Article 6 in their entirety and
substituting in lieu thereof the following new Sections:

                           6.6(g) Remedies Not Limited. Subject to Section
                  6.6(1) hereof, nothing contained in this Section 6.6 shall
                  limit the authority of the Board of Trustees to take such
                  other action as it deems necessary or advisable to protect the
                  Trust and the interests of its Shareholders by preserving the
                  Trust's REIT status.

                           6.6(l) New York Stock Exchange Transactions. Nothing
                  in this Section 6.6 (including without limitation the
                  authority of the Board contained in Section 6.6(g) hereof)
                  shall preclude the settlement of any transaction entered into
                  through the facilities of the New York Stock Exchange, any
                  successor exchange or quotation system thereto, or any other
                  exchange or quotation system over which the Shares may be
                  traded from time to time. The fact that the settlement of any
                  transaction occurs shall not negate the effect of any other
                  provision of this Article 6 and any transferee in such a
                  transaction shall be subject to all of the provisions and
                  limitations set forth in this Article 6.

                  SECOND: The foregoing amendments to the Declaration of Trust
of the Company have been duly advised by the Board of Trustees of the Company
and approved by the shareholders of the Trust as required by law.

                  THIRD: The undersigned President acknowledges these Articles
of Amendment to be the trust act of the Company and, as to all matters or facts
required to be verified under oath, the undersigned President acknowledges that,
to the best of his knowledge, information and belief, these matters and facts
are true in all material respects and that this statement is made under the
penalties for perjury.

                  IN WITNESS WHEREOF, the Company has caused these Articles of
Amendment to be signed in its name and on its behalf by its President and
attested to by its Secretary on this 15th day of May, 1998.

ATTEST:                                              BRANDYWINE REALTY TRUST



/s/ Mark S. Kripke                          /s/ Gerard H. Sweeney        (SEAL)
--------------------                        -----------------------------
Mark S. Kripke                              Gerard H. Sweeney
Assistant Secretary                         Chief Executive Officer
                                            and President
