
<PAGE>

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549




                                    FORM 8-K

                                 Current Report


                  Filed pursuant to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934



        Date of Report (Date of earliest event reported) August 11, 1998



                             BRANDYWINE REALTY TRUST
             -------------------------------------------------------
             (Exact name of registrant as specified in its charter)



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<CAPTION>
<S>                                                     <C>                        <C>  

              MARYLAND                                     1-9106                           23-2413352
    (State or Other Jurisdiction                         (Commission                     (I.R.S. Employer
          of Incorporation)                             file number)                  Identification Number)

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             16 Campus Boulevard, Newtown Square, Pennsylvania 19073
                    (Address of principal executive offices)


                                 (610) 325-5600
              (Registrant's telephone number, including area code)






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Item 2.   Acquisition or Disposition of Assets.

         (i) Consummation of the Lazard Transaction. On September 28, 1998,
Brandywine Realty Trust (the "Trust," and together with its subsidiaries, the
"Company") and Brandywine Operating Partnership, L.P. (the "Operating
Partnership") consummated the "Lazard Transaction." Reference is made to the
previous description of the Lazard Transaction contained in Item 5 "Lazard
Transaction" of the Company's Quarterly Report on Form 10-Q for the quarter
ended June 30, 1998 (the "Form 10-Q"). The information regarding the Lazard
Transaction contained in this Current Report on Form 8-K amends and supplements
the information regarding the Lazard Transaction previously provided by the
Company in the Form 10-Q. Defined terms used in the following discussion of the
Lazard Transaction but not defined below have the meanings given to them in the
Form 10-Q.

         At the September 28th closing, the Company acquired 67 of the Lazard
Properties (containing approximately 5.5 million net rentable square feet) for
an aggregate purchase price of approximately $591.6 million. The Company paid
approximately (i) $37.5 million of the acquisition price through the issuance of
$37.5 million in stated value of the Trust's Series A Preferred Shares (as
defined below), (ii) $74.5 million of the acquisition price through the issuance
of $74.5 million in stated value of the Operating Partnership's Series B
Preferred Units (as defined below), (iii) $239.7 million of the acquisition
price through the assumption of mortgage debt secured by 62 of the Lazard
Properties and (iv) $239.9 million of the acquisition price in cash (which was
funded through advances under the Company's $550 million revolving credit 
facility and the Company's $150 million credit facility).

         The Operating Partnership's acquisition of four of the 67 Lazard
Properties (known as Arboretum I, II, III and V) was structured so as to defer
transfer of title until the earlier of (i) receipt of consent to the transfer
from the lender that holds the mortgage on the properties and (ii) prepayment of
the loan. The Operating Partnership has agreed to prepay the loan by January 31,
1999 if lender consent to the transfer has not then been received. Upon transfer
of title to the properties, the Operating Partnership or the applicable seller
will pay to the other, as applicable, an amount equal to the economic benefits
or losses arising from the ownership of the properties from the September 28
closing date until the date of transfer of title. The Operating Partnership also
agreed to acquire the additional Lazard Property (commonly known as 8260
Greensboro Drive) not acquired at the September 28 closing on January 31, 1999,
subject to receipt of approval of a subdivision of such property from an
adjacent property (which adjacent property is the subject of a purchase option
held by the Operating Partnership). The acquisition price of 8260 Greensboro
Drive is $20.0 million, which is payable at the time of acquisition of such
property through the issuance of $20.0 million in stated value of the Operating
Partnership's Series B Preferred Units. The Company expects the required
subdivision to be approved prior to January 31, 1999.

         In exchange for the $591.6 million purchase price, the Operating
Partnership also acquired approximately 172 acres of undeveloped land and a 50%
general partnership interest in each of IR Northlight II Associates, a
Pennsylvania general partnership, and Interstate Center Associates, a Virginia
general partnership. In connection with the closing of the Lazard Transaction,
the Operating Partnership also (i) acquired the remaining 50% general
partnership interest in IR Northlight II Associates from a third party unrelated
to the Company or the Sellers in exchange


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for $7.5 million in cash (which was funded through advances under the Company's
$550 million revolving credit facility) and (ii) agreed to acquire (subject
to execution of the definitive documents and satisfaction of customary closing
conditions) the remaining 50% general partnership interest in Interstate Center
Associates from a third party unrelated to the Company or the Sellers in
exchange for approximately $2.1 million payable through the issuance of Class A
Units valued at $24.00 per unit. IR Northlight II Associates owns the Lazard
Property commonly known as 7350 Tilghman Street, Allentown, Pennsylvania, and
Interstate Center Associates owns the Lazard Property commonly known as
2100-2108 West Laburnum (Interstate Center), Richmond, Virginia.

         At the closing, the Operating Partnership also lent Commonwealth
Atlantic Land Company, one of the Sellers ("CALC"), $3.0 million which CALC used
to purchase $3.0 million in stated value of the Operating Partnership's Series B
Preferred Units. Such loan is evidenced by a promissory note (the "CALC Note")
in favor of the Operating Partnership which accrues interest at a rate of 7.25%
per annum and matures on September 30, 1999. The Operating Partnership may, at
its option, apply any outstanding principal amount of the CALC Note, together
with any accrued and unpaid interest thereon, towards the payment of the $68.0
million purchase price for an certain office property currently under
construction in Tyson's Corner, Virginia which is the subject of a purchase
option granted to the Operating Partnership as part of the Lazard Transaction.

         In connection with the Lazard Transaction, the Trust designated 750,000
of its authorized and unissued preferred shares of beneficial interest, par
value $.01 per share, as 7.25% Series A Cumulative Convertible Preferred Shares
(the "Series A Preferred Shares"). Each Series A Preferred Share has a stated
value (the "Stated Value") of $50 and is convertible into Common Shares at the
option of the holder at a conversion price (the "Conversion Price") of $28. The
Conversion Price will be reduced to $26.50 if the average closing price of the
Common Shares during the 60-trading day period ending on December 31, 2003 is
$23 or lower. At any time that the average market price of the Common Shares is
equal to or greater than 120% of the Conversion Price for 60 consecutive trading
days, the Trust has the right to redeem all or any part of the outstanding
Series A Preferred Shares for an amount in cash equal to the aggregate Stated
Value of the Series A Preferred Shares to be redeemed (plus accrued and unpaid
distributions) or for a number of Common Shares equal to the aggregate Stated
Value of the Series A Preferred Shares to be redeemed divided by the Conversion
Price (plus accrued and unpaid distributions). In addition, at any time on or
after January 2, 2004, the Trust has the right to redeem all or any part of the
outstanding Series A Preferred Shares for an amount in cash equal to the
aggregate Stated Value of the Series A Preferred Shares to be redeemed (plus
accrued and unpaid distributions) or, in the event that the average closing
price of the Common Shares is equal to or greater than 110% of the Conversion
Price for 60 consecutive trading days, for a number of Common Shares equal to
the aggregate Stated Value of the Series A Preferred Shares to be redeemed
divided by the Conversion Price (plus accrued and unpaid distributions). Each
Series A Preferred Share accrues distributions, payable in cash, in an amount
equal to the greater of (i) $0.9063 per quarter (equivalent to $3.625 per annum)
or (ii) the cash distributions paid or payable for the most recent quarter on
the number of Common Shares into which a Series A Preferred Share is
convertible. The holders of Series A Preferred Shares will have no voting rights
except (i) with respect to actions which would have a material and



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adverse effect on the rights of such holders and (ii) in the event
quarterly distributions on the Series A Preferred Shares are in arrears for six
or more quarters. In the event the quarterly distributions are so in arrears,
the holders of the Series A Preferred Shares will have the right, voting
together as a single class with any other class of the Trust's preferred shares
of beneficial interest ranking on a parity with the Series A Preferred Shares,
to elect two additional members to the Board of Trustees of the Trust (the
"Board").

         In exchange for the Trust's contribution to the Operating Partnership
of the properties acquired by the Trust in exchange for the issuance of the
Series A Preferred Shares, the Operating Partnership issued to the Trust $37.5
million in liquidation value of a newly created class of limited partner
interest (the "Series A Preferred Mirror Units"). The preferences of the Series
A Preferred Mirror Units "mirror" those of the Series A Preferred Shares. Upon
conversion of Series A Preferred Shares into Common Shares, an equal number of
Series A Preferred Mirror Units will be converted into an equal number of Class
A Units. Upon redemption of Series A Preferred Shares for cash, an equal number
of Series A Preferred Mirror Units will be canceled. Upon redemption of Series A
Preferred Shares for Common Shares, an equal number of Series A Preferred Mirror
Units will be redeemed for an equal number of Class A Units. Each Class A Unit
is redeemable, at the option of the holder, for either an amount of cash equal
to the trading price of one Common Share at the time of the redemption or, at
the option of the Trust, for one Common Share.

         In connection with the Lazard Transaction, the Operating Partnership
created Series B Preferred Units of limited partner interest (the "Series B
Preferred Units"). Each Class B Preferred Unit has a Stated Value of $50 and is
convertible into Class A Units at the option of the holder at the Conversion
Price. The Conversion Price is subject to reduction from $28.00 to $26.50 under
the circumstances identified above. At any time that the average market price of
the Common Shares is equal to or greater than 120% of the Conversion Price for
60 consecutive trading days, the Operating Partnership has the right to redeem
all or any part of the outstanding Series B Preferred Units for an amount in
cash equal to the aggregate Stated Value of the Series B Preferred Shares to be
redeemed (plus accrued and unpaid distributions), or for a number of Class A
Units equal to the aggregate Stated Value the Series B Preferred Shares to be
redeemed divided by the Conversion Price (plus accrued and unpaid
distributions). In addition, at any time on or after January 2, 2004, the
Operating Partnership has the right to redeem all or any part of the outstanding
Series B Preferred Units for an amount in cash equal to the aggregate Stated
Value the Series B Preferred Shares to be redeemed (plus accrued and unpaid
distributions) or, in the event that the average closing price of the Common
Shares is equal to or greater than 110% of the Conversion Price for 60
consecutive trading days, for a number of Class A Units equal to the aggregate
Stated Value the Series B Preferred Shares to be redeemed divided by the
Conversion Price (plus accrued and unpaid distributions). Each Class B Preferred
Unit accrues distributions, payable in cash, in an amount equal to the greater
of (i) $0.9063 per quarter (equivalent to $3.625 per annum) or (ii) the cash
distributions paid or payable on the number of Class A Units, or portion
thereof, into which a Class B Preferred Unit is convertible. The holders of
Series B Preferred Units have no voting rights except (i) with respect to
actions which would have a material and adverse effect on the rights of such
holders and (ii) in the event quarterly distributions on the Series B Preferred
Units are in arrears for six or



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more quarters. In the event quarterly distributions are so in arrears, holders
of Series B Preferred Units have the right, voting separately as a class, to
nominate two individuals who will vote as a group with the Board in connection
with any action to be taken by the Operating Partnership at the direction of the
Trust, as general partner, and as to which the Trust may act only upon
authorization by its Board. Except for transfers to affiliates of the Sellers or
upon the prior written consent of the Company, none of the Series B Preferred
Units, the Class A Units issuable upon redemption or conversion of the Series B
Preferred Units (the "Underlying Class A Units") nor the Common Shares issuable
upon redemption of the Underlying Class A Units may be transferred prior to
January 2, 2004.

         None of the securities issued in connection with the Lazard Transaction
nor the securities issuable upon the redemption or conversion thereof have been
registered under the Securities Act of 1933, as amended, or any state securities
laws and none of such securities may be offered and sold in the United States
absent registration or an applicable exemption from registration. The Company
has agreed to file registration statements registering the resale of the Series
A Preferred Shares, the Common Shares issuable upon the redemption or conversion
of the Series A Preferred Shares and the Common Shares issuable upon redemption
of the Underlying Class A Units.

         The definitive forms of the Articles Supplementary with respect to the
Preferred Shares, the Company's $550 million revolving credit facility and
pledge agreement with NationsBank, N.A., the Company's new $150 million credit
facility with NationsBanc Mortgage Capital Corp., the Fourth Amendment to the
Amended and Restated Agreement of Limited Partnership of the Operating
Partnership creating the Series A Preferred Mirror Units and the Fifth Amendment
to the Amended and Restated Agreement of Limited Partnership of the Operating
Partnership creating the Series B Preferred Units are attached hereto as
Exhibits 3.1, 10.1, 10.2, 10.3, 10.4 and 10.5, respectively.

         At closing, Murry N. Gunty, a principal of Lazard Freres Real Estate
Investors, L.L.C., a manager of realty investment funds ("LFREI"), and a senior
member of its investment team, became a member of the Board of Trustees of the
Company.

         (ii) Consummation of the Axinn Transaction. On October 6, 1998, the
Company and the Operating Partnership consummated the "Axinn Transaction."
Reference is made to the previous description of the Axinn Transaction contained
in Item 5 "Other Events" of the Company's Current Report on Form 8-K filed with
the Securities and Exchange Commission on July 30, 1998 (the "Prior 8-K"). The
information regarding the Axinn Transaction contained in this Current Report on
Form 8-K amends and supplements the information regarding the Axinn Transaction
previously provided by the Company in the Prior 8-K. Defined terms used in the
following discussion of the Axinn Transaction but not defined below have the
meanings given to them in the Prior 8-K.

         At the October 6th closing, the Company acquired 22 of the Axinn
Properties (containing approximately 889,993 net rentable square feet) for an
aggregate acquisition price of approximately $62.7 million. The Company paid
approximately $36.5 million of the acquisition 



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price in cash and approximately $26.2 million of the acquisition price through
the issuance of 1,127,895 Class A Units. The Company paid the cash portion of
the acquisition price through advances under its $550 million revolving credit 
facility and its $150 million credit facility. The Company did not assume any 
of the mortgage debt securing the acquired properties, which was discharged at 
the closing. At the closing, the Company also paid an aggregate of approximately
$1.1 million in connection with its agreement to acquire the properties known as
3 Paragon Drive and 101 Paragon Drive. As indicated in the Prior 8-K, the 
Company expects to acquire 3 Paragon Drive on or about December 28, 1998 and 
expects to acquire 101 Paragon Drive by September 2005.

         As indicated in the Prior 8-K, the Company has agreed to acquire the
property known as 31 Commercial Street only upon satisfaction of certain
environmental conditions relating to this property. As part of the Axinn
Transaction, the Company and the applicable Axinn Entities agreed to defer the
closing of two office properties in Long Island, New York (125 and 131 Jericho
Turnpike) until the closing of the 263 Old Country Road property closing. The
Company expects this closing to occur by approximately March 31, 1999. The
Company and the applicable Axinn Entities also agreed to remove from the
transaction the Long Island office property known as 163-167 South Service Road,
which the Company had previously agreed to acquire for approximately $2.8
million. In addition, the Company did not acquire the Long Island industrial
property known as 885 Waverly Road which, as indicated in the Prior 8-K, was
subject to a purchase right in favor of a tenant. The tenant exercised its
purchase right for this property.

         The definitive form of the Sixth Amendment to the Amended and Restated
Agreement of Limited Partnership of the Operating Partnership executed in
connection with the Axinn Transaction is attached hereto as Exhibit 10.6. The
First Amendment to Contribution Agreement, which provided for the
above-referenced changes and certain other matters, is attached hereto as
Exhibit 10.7.

         At closing, Donald E. Axinn, founder and chairman of the Donald E.
Axinn Companies, developers of office and industrial parks throughout the New
York metropolitan area since 1958, became a member of the Board of Trustees of
the Company.

Item 5.  Other Events

         From August 11, 1998 to September 2, 1998, the Company repurchased
86,744 of its Common Shares from the public at share prices ranging from $17.75
per share to $20.125 per share for a total of approximately $1.7 million.



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Item 7.  Financial Statements, Pro Forma Financial Information and Exhibits.

         (a) Financial Statements of Businesses Acquired.

         The required financial statements of the Lazard Properties and the
Axinn Properties will be included in an amendment to this Current Report on Form
8-K to be filed no later than December 12, 1998.

         (b) Pro Forma Financial Information.

         The required pro forma financial information which gives effect to the
Company's acquisition of the Lazard Properties and the Axinn Properties will be
included in an amendment to this Current Report Form 8-K by no later than
December 12, 1998.

         (c) Exhibits.

      3.1      Articles Supplementary
     10.1      Second Amended and Restated Credit Agreement
     10.2      Pledge Agreement
     10.3      Credit Agreement
     10.4      Fourth Amendment to the Amended and Restated Agreement of Limited
               Partnership of the Operating Partnership creating the Series A
               Preferred Mirror Units 
     10.5      Fifth Amendment to the Amended and Restated Agreement of Limited
               Partnership of the Operating Partnership creating the Series B 
               Preferred Units
     10.6      Sixth Amendment to the Amended and Restated Agreement of Limited
               Partnership of the Operating Partnership     
     10.7      First Amendment to Contribution Agreement




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                                    SIGNATURE

                  Pursuant to the requirements of the Securities Exchange Act of
1934, the Registrant has duly caused this report to be signed on its behalf by
the undersigned hereunto duly authorized.



                                            BRANDYWINE REALTY TRUST


Date:  October 13,1998                      By: /s/ Gerard H. Sweeney
                                            ------------------------------------
                                            Title:   President and Chief
                                                     Executive Officer




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