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                                                                     Exhibit 5.2


                                December 23, 1998


Brandywine Realty Trust
14 Campus Boulevard
Newton Square, Pennsylvania 19073

         Re:      Registration Statement on Form S-3
                  ----------------------------------

Ladies and Gentlemen:

                We have served as Maryland counsel to Brandywine Realty Trust, a
Maryland real estate investment trust (the "Company"), in connection with
certain matters of Maryland law arising out of the registration of (i) 750,000
Series A Preferred Shares of Beneficial Interest, $.01 par value per share (the
"Preferred Shares"), which previously have been issued in connection with the
acquisition of a portfolio of properties (the "Acquisition") by the Operating
Partnership of which the Company is the general partner and (ii) 2,542,990
Common Shares of Beneficial Interest, $.01 par value per share (the "Common
Shares"), of the Company (collectively, the "Shares"), covered by a Registration
Statement on Form S-3, and all amendments thereto (the "Registration
Statement"), under the Securities Act of 1933, as amended (the "1933 Act").
Unless otherwise defined herein, capitalized terms used herein shall have the
meanings assigned to them in the Registration Statement.

         In connection with our representation of the Company, and as a basis
for the opinion hereinafter set forth, we have examined originals, or copies
certified or otherwise identified to our satisfaction, of the following
documents (collectively, the "Documents"):

        1. The Registration Statement, including the related form of prospectus
included therein, in the form in which it was transmitted to the Securities and
Exchange Commission (the "Commission") under the 1933 Act;

        2. The Amended and Restated Declaration of Trust of the Company, as
amended (the "Declaration"), certified as of a recent date by the State
Department of Assessments and Taxation of Maryland (the "SDAT");

         3. The Bylaws of the Company, certified as of a recent date by its
Secretary;

        4. Resolutions adopted by the Board of Trustees, or a duly authorized
committee thereof, of the Company relating to the sale, issuance and
registration of the Shares, certified as of a recent date by the Secretary of
the Company;

         5. The form of certificate evidencing a Common Share, certified as of a
recent date by the Secretary of the Company;

         6. The form of certificate evidencing a Preferred Share, certified as
of a recent date by the Secretary of the Company;

         7. A certificate of the SDAT as to the good standing of the Company,
dated as of a recent date;

        8. A certificate executed December 23, 1998 by Brad A. Molotsky,
Secretary of the Company, which we have assumed is true and correct as of the
date hereof; and

        9. Such other documents and matters as we have deemed necessary or
appropriate to express the opinion set forth in this letter, subject to the
assumptions, limitations and qualifications stated herein.

         In expressing the opinion set forth below, we have assumed, and so far
as is known to us there are no facts inconsistent with, the following:

        1. Each individual executing any of the Documents, whether on behalf of
such individual or another person, is legally competent to do so.




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        2. Each individual executing any of the Documents on behalf of a party
(other than the Company) is duly authorized to do so.

        3. Each of the parties (other than the Company) executing any of the
Documents has duly and validly executed and delivered each of the Documents to
which such party is a signatory, and such party's obligations set forth therein
are legal, valid and binding.

        4. All Documents submitted to us as originals are authentic. All
Documents submitted to us as certified or photostatic copies conform to the
original documents. All signatures on all such Documents are genuine. All public
records reviewed or relied upon by us or on our behalf are true and complete.
All statements and information contained in the Documents are true and complete.
There has been no oral or written modification or amendment to any of the
Documents, and there has been no waiver of any provision of the Documents, by
action or omission of the parties or otherwise.

        5. The Shares will not be transferred in violation of any restriction or
limitation contained in the Declaration.

        6. The Company will be in good standing with the SDAT on the date on
which the Securities are actually issued.

              The phrase "known to us" is limited to the actual knowledge,
without independent inquiry, of the lawyers at our firm who have performed legal
services in connection with the issuance of this opinion.

         Based upon the foregoing, and subject to the assumptions, limitations
and qualifications stated herein, it is our opinion that:

        1. The Company is a real estate investment trust duly formed and
existing under and by virtue of the laws of the State of Maryland and is in good
standing with the SDAT.

        2. The Common Shares are duly authorized and (assuming that the sum of:
(a) all common shares of beneficial interest issued as of the date hereof (not
including any of the Common Shares), (b) any common shares of beneficial
interest issued between the date hereof and the date on which any of the Common
Shares are actually issued (not including any of the Common Shares) and (c) the
Common Shares, will not exceed the total number of common shares of beneficial
interest that the Company is then authorized to issue) will be, upon issuance in
accordance with their terms and resolutions of the Board of Trustees of the
Company authorizing their issuance, validly issued, fully paid and
nonassessable.

        3. The Preferred Shares issued by the Company in connection with the
Acquisition have been duly authorized and are validly issued, fully paid and
nonassessable.

              The foregoing opinion is limited to the laws of the State of
Maryland and we do not express any opinion herein concerning any other law. We
express no opinion as to the applicability or effect of any federal or state
laws, including the securities laws of the State of Maryland or federal or state
laws regarding fraudulent transfers. To the extent that any matter as to which
our opinion is expressed herein would be governed by any jurisdiction other than
the State of Maryland, we do not express any opinion on such matter.

             We assume no obligation to supplement this opinion if any
applicable law changes after the date hereof or if we become aware of any fact
that might change the opinion expressed herein after the date hereof.

         This opinion is being furnished to you solely for submission to the
Commission as an exhibit to the Registration Statement and, accordingly, may not
be relied upon by, quoted in any manner to, or delivered to any other person or
entity (other than Pepper Hamilton LLP, counsel to the Company) without, in each
instance, our prior written consent.




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                We hereby consent to the filing of this opinion as an exhibit to
the Registration Statement and to the use of the name of our firm therein. In
giving this consent, we do not admit that we are within the category of persons
whose consent is required by Section 7 of the 1933 Act.


                                      Very truly yours,

                                      /s/ Ballard Spahr Andrews & Ingersoll, LLP
                                      ------------------------------------------
                                      Ballard Spahr Andrews & Ingersoll, LLP



