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                                                                     Exhibit 5.2




                                  June 5, 1998




Brandywine Realty Trust
16 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) the
following securities of the Company having an aggregate initial offering price
of up to $633,129,026 (collectively, the "Securities"): (a) common shares of
beneficial interest, $.01 par value per share ("Common Shares"), (b) one or more
series of preferred shares of beneficial interest, $.01 par value per share
("Preferred Shares"), (c) one or more series of Preferred Shares represented by
depositary receipts ("Depositary Shares"), and (d) warrants to purchase Common
Shares, Preferred Shares or Depositary Shares (the "Warrants") and (ii)
unconditional and irrevocable guarantees by the Company ("Guarantees") of up to
$750,000,000 aggregate initial offering price of debt securities (the "Debt
Securities") by Brandywine Operating Partnership, L.P. (the "Operating
Partnership"), covered by the above-referenced Registration Statement, 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 and the related form of
prospectus included therein in the form in which it was transmitted to the
Securities and Exchange 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 (the "Bylaws"), certified as of a
recent date by its Secretary;

                  4. Resolutions adopted by the Board of Trustees of the Company
relating to the sale, issuance and registration of the Securities and the Debt
Securities, certified as of a recent date by the Secretary of the Company;

                  5. The form of certificate representing the Common Shares,
certified as of a recent date by its Secretary;




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                  6. The form of certificate representing the Preferred Shares,
certified as of a recent date by its Secretary;

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

                  8. A certificate executed June 5, 1998 by Brad A. Molotsky,
Secretary of the Company, which we have assumed is true and complete; 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.

                  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 any of the
Documents, by action or omission of the parties or otherwise.

                  5. The outstanding shares of beneficial interest of the
Company have not been and will not be transferred in violation of any
restriction or limitation contained in the Declaration. The Securities and the
Debt Securities will not be transferred in violation of any restriction or
limitation contained in the Declaration.

                  6. The issuance of, and certain terms of, the Securities and
the Debt Securities to be issued by the Company or the Operating Partnership, as
the case may be, from time to time will be approved by the Board of Trustees of
the Company or a duly authorized committee thereof in accordance with Maryland
law (the "Trust Proceedings").

                  7. Any Debt Securities which are the subject of Guarantees
will be issued pursuant to an indenture (an "Indenture") between the Operating
Partnership, the Company and a trustee for the benefit of the holders of the
Debt Securities.

         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:




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                  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. Upon the completion of all Trust Proceedings relating to
the Securities that are Common Shares (the "Common Securities") and the due
execution, countersignature and delivery of certificates evidencing the Common
Securities and assuming that the sum of (a) all Common Shares issued as of the
date hereof, (b) any Common Shares issued between the date hereof and the date
on which any of the Common Securities are actually issued (not including any of
the Common Securities), and (c) the Common Securities will not exceed the total
number of Common Shares that the Company is then authorized to issue, the Common
Securities are duly authorized and, when and if delivered against payment
therefor in accordance with the resolutions of the Board of Trustees of the
Company authorizing their issuance, will be validly issued, fully paid and
nonassessable.

                  3. Upon the completion of all Trust Proceedings relating to
the Securities that are Preferred Shares (the "Preferred Securities") and the
due execution, countersignature and delivery of certificates evidencing the
Preferred Securities and assuming that the sum of (a) all Preferred Shares
issued as of the date hereof, (b) any Preferred Shares issued between the date
hereof and the date on which any of the Preferred Securities are actually issued
(not including any of the Preferred Securities), and (c) the Preferred
Securities will not exceed the total number of Preferred Shares that the Company
is then authorized to issue, the Preferred Securities are duly authorized and,
when and if delivered against payment therefor in accordance with the
resolutions of the Board of Trustees of the Company authorizing their issuance,
will be validly issued, fully paid and nonassessable.

                  4. Upon completion of all Trust Proceedings relating to
Guarantees, and upon the due execution of delivery of the Debt Securities
pursuant to the Indenture, the Guarantees will be duly authorized by all
necessary trust action of the Company, and the Guarantees will be legally issued
and will be binding obligations of the Company.

         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 compliance with the securities (or "blue sky") laws or the real
estate syndication laws of the State of Maryland.

         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
Securities and Exchange 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.

         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

