
<PAGE>   1

THE SECURITIES REPRESENTED HEREBY AND ISSUABLE UPON EXERCISE HEREOF HAVE NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE "ACT"), OR
UNDER THE SECURITIES LAWS OF ANY STATE.  ALL SUCH SECURITIES ARE SUBJECT TO
RESTRICTIONS ON TRANSFERABILITY AND RESALE AND MAY NOT BE TRANSFERRED OR RESOLD
EXCEPT AS PERMITTED UNDER THE ACT AND THE APPLICABLE STATE SECURITIES LAWS,
PURSUANT TO REGISTRATION OR EXEMPTION THEREFROM.  THE ISSUER OF SUCH SECURITIES
MAY REQUIRE AN OPINION OF COUNSEL IN FORM AND SUBSTANCE REASONABLY SATISFACTORY
TO THE ISSUER TO THE EFFECT THAT ANY PROPOSED TRANSFER OR RESALE IS IN
COMPLIANCE WITH THE ACT AND ANY APPLICABLE STATE SECURITIES LAWS.

           Void after 5:00 p.m. New York Time, on November 14, 1998.

                            BRANDYWINE REALTY TRUST

          Warrant Agreement for the Purchase of Shares of Common Stock


No. 1                                                             400,000 Shares

                 FOR VALUE RECEIVED, BRANDYWINE REALTY TRUST, a Maryland real
estate investment trust (the "Company"), with its principal office at 16 Campus
Boulevard, Suite 150, Newtown Square, Pennsylvania 19073, hereby certifies that
RAI Real Estate Advisers, Inc. as voting trustee of a voting trust dated as of
November 6 ,1996 or its assigns (the "Holder") is entitled, subject to the
provisions of this Warrant, to purchase from the Company, at any time before
5:00 p.m. (Eastern Time) on November 14, 1998 (the "Expiration Date"), the
number of fully paid and nonassessable common shares of beneficial interest of
the Company (the "Common Stock") set forth above, subject to adjustment as
hereinafter provided.

                 The Holder may purchase such number of shares of Common Stock
at a purchase price per share (as appropriately adjusted pursuant to Section 6,
Section 8 or Section 9 hereof) of Eight Dollars and 50/100 Cents ($8.50) (the
"Exercise Price").  As provided in Section 6(j), the term "Common Stock" shall
mean the aforementioned Common Stock of the Company, together with any other
equity securities that may be issued by the Company in addition thereto or in
substitution therefor as provided herein.

                 The number of shares of Common Stock to be received upon the
exercise of this Warrant and the price to be paid for a share of Common Stock
are subject to adjustment from time to time as hereinafter set forth.  The
shares of Common Stock deliverable upon such exercise, as adjusted from time to
time, are hereinafter sometimes referred to as "Warrant Shares."





                                      -1-
<PAGE>   2


                 Section 1.       Exercise of Warrant.  (a) This Warrant may be
exercised in whole or in part on any business day (the "Exercise Date")
occurring from and after the date hereof and on or before the Expiration Date
by presentation and surrender hereof to the Company at its principal office at
the address set forth in the initial paragraph hereof or at the office of its
stock transfer or warrant agent, if any, (or at such other address as the
Company may hereafter notify the Holder in writing) with the Purchase Form
annexed hereto duly executed and accompanied by proper payment of the Exercise
Price in lawful money of the United States of America in the form of a check,
subject to collection, for the number of Warrant Shares specified in the
Purchase Form.  If this Warrant should be exercised in part only, the Company
shall, upon surrender of this Warrant, execute and deliver a new Warrant
evidencing the rights of the Holder thereof to purchase the balance of the
Warrant Shares purchasable hereunder.  Upon receipt by the Company of this
Warrant and such Purchase Form, together with proper payment of the Exercise
Price, at such office, the Holder shall be deemed to be the holder of record of
such Warrant Shares, notwithstanding that the stock transfer books of the
Company shall then be closed or that certificates representing such Warrant
Shares shall not then be actually delivered to the Holder, which certificates
shall be delivered to the Holder within two (2) business days following the
Company's receipt of the Warrant together with the aforesaid Purchase Form and
payment.  The Company shall pay any and all documentary stamp or similar issue
or transfer taxes payable in respect of the issue or delivery of the Warrant
Shares.

                 (b)      In addition to and without limiting the rights of the
Holder under any other terms set forth herein, the Holder shall have, upon
written request by the Holder delivered or transmitted to the Company together
with this Warrant, the right (the "Conversion Right") to require the Company to
convert this Warrant into shares of Common Stock as follows:  upon exercise of
the Conversion Right, the Company shall deliver to the Holder (without payment
by the Holder of any Exercise Price) that number of shares of Common Stock that
is equal to the quotient obtained by dividing (x) the value of this Warrant at
the time the Conversion Right is exercised (determined by subtracting the
aggregate Exercise Price in effect immediately prior to the exercise of the
Conversion Right from the aggregate current market price (determined as
provided in Section 11 below) of the shares of Common Stock issuable upon
exercise of this Warrant immediately prior to the exercise of the Conversion
Right) by (y) the current market price of one share of Common Stock (determined
as provided in Section 11 below) immediately prior to the exercise of the
Conversion Right.

                 The Conversion Right referred to above may be exercised by the
Holder by surrender of this Warrant at the principal office of the Company or
at the offices of its stock transfer or warrant agent, if any, together with a
written statement specifying that the Holder thereby intends to exercise the
Conversion Right.  Certificates representing shares of Common Stock issuable
upon exercise of the Conversion Right shall be delivered to the Holder within
two (2) business days following the Company's receipt of this Warrant together
with the aforesaid written statement.

                 Section 2.       Reservation of Shares.  The Company shall
reserve at all times for issuance and delivery upon exercise of this Warrant
all shares of its Common Stock or other





                                      -2-
<PAGE>   3

shares of beneficial interest of the Company from time to time issuable upon
exercise of this Warrant.  All such shares shall be duly authorized and, when
issued upon the exercise of the Warrant in accordance with the terms hereof,
shall be validly issued, fully paid and nonassessable, free and clear of all
taxes, liens, security interests, charges and other encumbrances or
restrictions (other than restrictions pursuant to applicable federal and state
securities laws) and free and clear of all preemptive rights.  If the Common
Stock is listed on any national securities exchange or The Nasdaq Stock Market,
the Company shall also list the shares issuable upon exercise of the Warrant on
such exchange, subject to notice of issuance, or include the shares issuable
upon exercise of this Warrant in the listing of its Common Stock on The Nasdaq
Stock Market, as the case may be.

                 Section 3.       Fractional Interest.  The Company will not
issue a fractional share of Common Stock or scrip upon any exercise or
conversion of this Warrant.  Instead, the Company shall issue the next highest
number of whole shares of Common Stock.

                 Section 4.       Exchange, Transfer, Assignment or Loss of
Warrant.

                 (a)      The Holder of this Warrant may not transfer or assign
its interest in this Warrant, or any of the Warrant Shares, in whole or in
part, unless, prior to any such transfer, the transferee agrees in writing, in
form and substance satisfactory to the Company, to be bound by the terms of
this Agreement and provides the Company with an opinion of counsel in such form
reasonably acceptable to the Company, that such transfer would not be in
violation of the Act or any applicable state securities laws.

                 (b)      Subject to the provisions of subsection (a) above and
Section 10, upon surrender of this Warrant to the Company or its stock transfer
agent or warrant agent, accompanied by the Assignment Form annexed hereto duly
executed and funds sufficient to pay any transfer tax, the Company shall,
without charge, execute and deliver a new Warrant or Warrants in the name of
the assignee or assignees named in such instrument of assignment and, if the
Holder's entire interest is not being assigned, in the name of the Holder, and
this Warrant shall promptly be canceled.

                 (c)      This Warrant may be divided by or combined with other
Warrants which carry the same rights upon presentation hereof at the principal
office of the Company or at the office of its stock transfer or warrant agent,
if any, together with a written notice specifying the names and denominations
in which new Warrants are to be issued and signed by the Holder hereof.  The
term "Warrant" as used herein includes any warrants into which this Warrant may
be divided or exchanged.

                 (d)      Upon receipt of evidence satisfactory to the Company
of the loss, theft, destruction or mutilation of this Warrant, and (in the case
of loss, theft or destruction) of indemnification reasonably satisfactory to
the Company, and upon surrender and cancellation of this Warrant, if mutilated,
the Company shall execute and deliver a new Warrant of like tenor and date
registered in the Holder's name representing the number of shares purchasable
under





                                      -3-
<PAGE>   4

the original Warrant.  Any such new Warrant executed and delivered shall
constitute an additional contractual obligation of the Company, whether or not
the original Warrant shall be at any time enforceable by anyone.

                 Section 5.       Rights of the Holder.  The Holder shall not,
by virtue hereof, be entitled to any rights of a shareholder in the Company,
either at law or equity, and the rights of the Holder are limited to those set
forth in this Warrant.

                 Section 6.       Adjustment of Exercise Price and Number of
Shares.  The number and kind of securities purchasable upon the exercise of
this Warrant and the Exercise Price shall be subject to adjustment from time to
time upon the occurrence of certain events, as follows:

                 (a)      Adjustment for Change in Beneficial Interest.  If at
any time after November 6, 1996, the Company:

                          (i)   pays a dividend or makes a distribution on its
                          Common Stock in shares of its Common Stock;

                          (ii)  subdivides its outstanding shares of Common
                          Stock into a greater number of shares;

                          (iii) combines its outstanding shares of Common Stock
                          into a smaller number of shares;

                          (iv)  makes a distribution on its Common Stock in
                          shares of its beneficial interest other than Common
                          Stock; or

                          (v)   issues by reclassification of its Common Stock
                          any shares of its beneficial interest;

then the Exercise Price in effect (and the number of Warrant Shares and other
securities, if any, issuable upon exercise of this Warrant) immediately prior
to such action shall be adjusted so that the Holder may receive upon exercise
of the Warrant, and payment of the same aggregate consideration, the number of
shares of beneficial interest of the Company which the Holder would have owned
immediately following such action if the Holder had exercised the Warrants
immediately prior to such action.

                 The adjustment shall become effective immediately after the
record date in the case of such a dividend or distribution, and immediately
after the effective date in the case of a subdivision, combination or
reclassification.





                                      -4-
<PAGE>   5

                 (b)      Adjustment for Other Distributions.  If at any time
after November 6, 1996, the Company distributes to all holders of its Common
Stock any of its assets or debt securities, the Exercise Price following the
record date for such distribution shall be adjusted in accordance with the
following formula:

                                                    M-F 
                                                    ---                 
                                           E' = E x  M

where:           E'       =       the adjusted Exercise Price.

                 E        =       the then current Exercise Price immediately
                                  prior to the adjustment.

                 M        =       the current market price (determined as
                                  provided in Section 11 below) per share of
                                  Common Stock on the record date of the
                                  distribution.

                 F        =       the aggregate fair market value (determined
                                  in such reasonable manner as may be
                                  prescribed in good faith by the Board of
                                  Trustees of the Company) on the record date
                                  of the distribution of the assets or debt
                                  securities divided by the number of
                                  outstanding shares of Common Stock.

                 The adjustment shall be made successively whenever any such
distribution is made and shall become effective immediately after the record
date for the determination of shareholders entitled to receive the distribution
or the effective date of such issuance, as applicable.  Notwithstanding the
formula above, in no event shall the adjusted Exercise Price be less than zero.
In the event that such distribution or issuance is not actually made, the
Exercise Price shall again be adjusted to the Exercise Price as determined
without giving effect to the calculation provided hereby.

                 This subsection does not apply to ordinary quarterly cash
dividends or cash distributions paid out of consolidated current or retained
earnings as shown on the books of the Company and paid in the ordinary course
of business.

                 (c)      Deferral of Issuance or Payment.  In any case in
which an event covered by this Section 6 shall require that an adjustment in
the Exercise Price be made effective as of a record date, the Company may elect
to defer until the occurrence of such event (i) issuing to the Holder, if this
Warrant is exercised after such record date, the shares of Common Stock and
other beneficial interest of the Company, if any, issuable upon such exercise
over and above the shares of Common Stock or other beneficial interest of the
Company, if any, issuable upon such exercise on the basis of the Exercise Price
in effect prior to such adjustment, and (ii) paying to the Holder by check any
amount in lieu of the issuance of fractional shares pursuant to Section 11.





                                      -5-
<PAGE>   6

                 (d)      When No Adjustment Required.  No adjustment need be
made for a change in the par value of the Common Stock.

                 (e)      Notice of Certain Actions.  In the event that:

                          (i)     the Company shall authorize the issuance to
all holders of its Common Stock of rights, warrants, options or convertible
securities to subscribe for or purchase shares of its Common Stock, or of any
other subscription rights, warrants, options or convertible securities; or

                          (ii)    the Company shall authorize the distribution
to all holders of its Common Stock of evidences of its indebtedness or assets
(other than dividends paid in or distributions of the Company's beneficial
interest for which the Exercise Price shall have been adjusted pursuant to
subsection (a) of this Section 6) or cash dividends or cash distributions
payable out of consolidated current or retained earnings as shown on the books
of the Company and paid in the ordinary course of business); or

                          (iii)   the Company shall authorize any capital
reorganization or reclassification of the Common Stock (other than a
subdivision or combination of the outstanding Common Stock and other than a
change in par value of the Common Stock) or any consolidation or merger to
which the Company is a party and for which approval of any shareholders of the
Company is required (other than a consolidation or merger in which the Company
is the continuing corporation and that does not result in any reclassification
or change of the Common Stock outstanding), or the conveyance or transfer of
the properties and assets of the Company as an entirety or substantially as an
entirety; or

                          (iv)    the Company is the subject of a voluntary or
involuntary dissolution, liquidation or winding-up procedure; or

                          (v)     the Company proposes to take any action
(other than actions of the character described in subsection (a) of this
Section 6) that would require an adjustment of the Exercise Price pursuant to
this Section 6;

then the Company shall cause to be mailed by first-class mail to the Holder, at
least ten (10) days prior to the applicable record or effective date, a notice
stating (x) the date as of which the holders of Common Stock of record to be
entitled to receive any such rights, warrants or distributions are to be
determined, or (y) the date on which any such consolidation, merger,
conveyance, transfer, dissolution, liquidation or winding-up is expected to
become effective, and the date as of which it is expected that holders of
Common Stock of record shall be entitled to exchange their shares of Common
Stock for securities or other property, if any, deliverable upon such
reorganization, reclassification, consolidation, merger, conveyance, transfer,
dissolution, liquidation or winding-up.





                                      -6-
<PAGE>   7

                 (f)      No Adjustment Upon Exercise of Warrants.  No
adjustments shall be made under any Section herein in connection with the
issuance of Warrant Shares upon exercise of the Warrants.

                 (g)      Common Stock Defined.  The term "Common Stock" shall
include any equity securities of any class of the Company hereinafter
authorized which shall not be limited to a fixed sum or percentage in respect
of the right of the holders thereof to participate in dividends, or to
participate in distributions of assets upon the voluntary or involuntary
liquidation, dissolution or winding up of the Company.  However, subject to the
provisions of Section 8 hereof, shares issuable upon exercise hereof shall
include only shares of the class designated as Common Stock of the Company as
of the date hereof or shares of any class or classes resulting from any
reclassification or reclassifications thereof or as a result of any corporate
reorganization as provided for in Section 8 hereof.

                 (h)      Warrants Issued After Adjustments.  Irrespective of
any adjustments in the Exercise Price or the number or kind of Warrant Shares
purchasable upon exercise of this Warrant, Warrants theretofore or thereafter
issued may continue to express the same price and number and kind of shares as
are stated in the similar warrants initially issuable pursuant to this
Agreement.

                 Section 7.       Officers' Certificate.  Whenever the Exercise
Price shall be adjusted as required by the provisions of Section 6, the Company
shall forthwith file in the custody of its Secretary or an Assistant Secretary
at its principal office an officers' certificate showing the adjusted Exercise
Price determined as herein provided, setting forth in reasonable detail the
facts requiring such adjustment and the manner of computing such adjustment.
Each such officers' certificate shall be signed by the Chairman, President or
Chief Financial Officer of the Company and by the Secretary or any Assistant
Secretary of the Company.  A copy of each such officers' certificate shall be
promptly mailed, by certified mail, to each holder of a Warrant and the
original shall be made available at all reasonable times for inspection by any
other holder of a Warrant executed and delivered pursuant to Section 4 hereof.

                 Section 8.       Reclassification, Reorganization,
Consolidation or Merger.  In the event of any reclassification, capital
reorganization or other change of outstanding shares of Common Stock of the
Company (other than a subdivision or combination of the outstanding Common
Stock and other than a change in the par value of the Common Stock) or in the
event of any consolidation or merger of the Company with or into another person
or entity (other than a merger in which the Company is the continuing person or
entity and that does not result in any reclassification, capital reorganization
or other change of outstanding shares of Common Stock of the class issuable
upon exercise of this Warrant) or in the event of any sale, lease, transfer or
conveyance to another person or entity of the property and assets of the
Company as an entirety or substantially as an entirety, the Company shall, as a
condition precedent to such transaction, cause effective provisions to be made
so that the Holder shall have the right thereafter, by exercising this Warrant,
to purchase the kind and amount of shares of beneficial interest and other
securities and property (including cash) receivable upon such reclassification,





                                      -7-
<PAGE>   8

capital reorganization and other change, consolidation, merger, sale or
conveyance by a holder of the number of shares of Common Stock that might have
been received upon exercise of this Warrant immediately prior to such
reclassification, capital reorganization, change, consolidation, merger, sale
or conveyance.  Any such provision shall include provisions for adjustments in
respect of such shares of beneficial interest and other securities and property
that shall be as nearly equivalent as may be practicable to the adjustments
provided for in this Warrant.  The foregoing provisions of this Section 8 shall
similarly apply to successive reclassifications, capital reorganizations and
changes of shares of Common Stock and to successive consolidations, mergers,
sales or conveyances.  In the event that in connection with any such capital
reorganization, or classification, consolidation, merger, sale or conveyance,
additional shares of Common Stock shall be issued in exchange, conversion,
substitution or payment, in whole or in part, for, or of, a security of the
Company other than Common Stock, any such issue shall be treated as an issue of
Common Stock covered by the provisions of Section 6 hereof.

                 Section 9.       Duty to Make Fair Adjustments in Certain
Cases.  If any event occurs as to which, in the reasonable opinion of either
the Board of Trustees of the Company or a majority of the holders of the
warrants then outstanding under this Warrant, the Warrants issued to the Turkey
Vulture Fund XIII, Ltd. on June 21, 1996, the Warrants issued to Safeguard on
August 22, 1996 and any warrants issued upon repayment of unsecured debt issued
to or held by Osborne (collectively, the "Other Warrants"), the provisions of
Section 6 and Section 8 hereof are not strictly applicable or, if strictly
applicable, would not fairly protect the purchase rights of the holders of such
warrants in accordance with the essential intent and principles of such
provisions, then the Board of Trustees of the Company and a majority of the
holders of the warrants then outstanding under this Warrant and the Other
Warrants shall mutually agree upon an adjustment in the application of such
provisions, in accordance with such essential intent and principles, so as to
protect such purchase rights as aforesaid.

                 Section 10.      Transfer to Comply with the Securities Act of
1933; Registration Rights.

                 (a)      No sale, transfer, assignment, hypothecation or other
disposition of this Warrant or of the Warrant Shares shall be made if such
sale, transfer, assignment, hypothecation or other disposition would result in
a violation of the Act, or any state securities laws.  Upon exercise of this
Warrant, the Holder shall, if requested by the Company, confirm in writing, in
a form reasonably satisfactory to the Company, that the shares of Common Stock
so purchased are being acquired solely for the Holder's own account, and not as
a nominee thereof, for investment, and not with a view toward distribution or
resale, except as permitted by the Act, and shall provide such other
information to the Company as the Company may reasonably request.  Any Warrant
and any Warrants issued upon substitution for, or upon assignment or transfer
of this Warrant, as the case may be, and all shares of Common Stock issued upon
exercise hereof or conversion thereof shall bear a legend (in addition to any
legend required by state securities laws) in substantially the form set forth
on the first page of this Warrant, unless and until such securities have been
transferred pursuant to an effective registration statement





                                      -8-
<PAGE>   9

under the Act or may be freely sold to the public pursuant to Rule 144 (or any
successor rule thereto) or otherwise.

                 (b)  The Holder and any transferee of the Warrant or the
Warrant Shares issuable hereunder shall have the right to require the Company
to register the Warrant Shares with the Securities and Exchange Commission for
resale as provided in the Registration Rights Agreement of even date herewith
by and between the Holder and the Company.

                 Section 11.      Current Market Price.  The "current market
price" of a share of Common Stock for purposes of this Agreement shall be
determined as follows:

                 (a)      If the Common Stock is listed on a national
securities exchange or admitted to unlisted trading privileges on such exchange
or listed for trading on The Nasdaq Stock Market, the current market price
shall be the last reported sale price of the Common Stock on such exchange or
system on the last business day prior to the date of exercise of this Warrant,
or if no such sale is made on such day, the average of the closing bid and
asked prices of the Common Stock for such day on such exchange or system; or

                 (b)      If the Common Stock is not so listed or admitted to
unlisted trading privileges, the current market price shall be the average of
the last reported bid and asked prices reported by the National Quotation
Bureau, Inc., on the last business day prior to the date of exercise of this
Warrant; or

                 (c)      If the Common Stock is not so listed or admitted to
unlisted trading privileges and bid and asked prices are not so reported, the
current market price per share shall be an amount, not less than 90% of the
book value per share of the Common Stock as at the end of the most recent
fiscal year of the Company ending prior to the date of the exercise of this
Warrant, determined in such reasonable manner as may be prescribed in good
faith by the Board of Trustees of the Company.

                 Section 12.      Modification and Waiver.  Neither this
Warrant nor any term hereof may be changed, waived, discharged or terminated
other than by an instrument in writing signed by the Company and by the Holder.

                 Section 13.      Notices.  Any notice, request or other
document required or permitted to be given or delivered to the Holder or the
Company shall be delivered or shall be sent by certified mail, postage prepaid,
or by overnight courier to each such holder at its address as shown on the
books of the Company or to the Company at the address indicated therefor in the
first paragraph of this Warrant.

                 Section 14.      Descriptive Headings and Governing Law.  The
description headings of the several sections and paragraphs of this Warrant are
inserted for convenience only and do not constitute a part of this Warrant.
This Warrant shall be construed and enforced in





                                      -9-
<PAGE>   10

accordance with, and the rights of the parties shall be governed by, the laws
of the State of Maryland.

                 Section 15.      No Impairment.  The Company will not
knowingly avoid or seek to avoid the observance or performance of any of the
terms to be observed or performed hereunder by it, but will at all times in
good faith assist in the carrying out of all of the provisions of this Warrant.

                 Section 16.      Non-Recourse.  No recourse shall be had for
any obligation of the Company hereunder, or for any claim based thereon or
otherwise in respect thereof, against any past, present or future trustee,
shareholder, officer or employee of the Company, whether by virtue of any
statute or rule of law, or by the enforcement of any assessment or penalty or
otherwise, all such other liability being expressly waived and released by each
other party hereto.

                 IN WITNESS WHEREOF, the Company has duly caused this Warrant
to be signed by its duly authorized officer and to be dated as of November 14,
1996.

                                 BRANDYWINE REALTY TRUST



                                 By: /s/ John M. Adderly, Jr.                  
                                    -------------------------------------------
                                      John M. Adderly, Jr., Vice President





                                      -10-
<PAGE>   11


                                 PURCHASE FORM


                                                 Dated:
                                                       ------------------------

                 The undersigned hereby irrevocably elects to exercise the
within Warrant to purchase _____________ shares of Common Stock and hereby
makes payment of ___________________________ in payment of the exercise price
thereof.



                                               Signature
                                                        -----------------------





                                      -11-
<PAGE>   12

                                ASSIGNMENT FORM


                                        Dated:
                                              ----------------------------------


         FOR VALUE RECEIVED,__________________hereby sells, assigns and
transfers unto ________________________________ (the "Assignee"),
                          (please type or print in block letters)

________________________________________________________________________________
                         (insert address)
                                                  
its right to purchase up to __________ shares of Common Stock represented by
this Warrant and does hereby irrevocably constitute and appoint
_______________________________ Attorney, to transfer the same on the books of
the Company, with full power of substitution in the premises.



                                        Signature 
                                                 -------------------------------





                                      -12-
