Stock Purchase Agreement - Equity Office Properties Management Corp. and Beacon Property Management Corp.


                          STOCK PURCHASE AGREEMENT


     THIS STOCK PURCHASE AGREEMENT (the 'Agreement'), dated as of September 14,
1997, is made and entered into among Equity Office Properties Management Corp.,
a Delaware corporation ('Purchaser'), and the undersigned stockholders (each, a
'Stockholder,' and collectively, the 'Stockholders') of Beacon Property
Management Corporation, a Delaware corporation (the 'Company').

     WHEREAS, Equity Office Properties Trust, a Maryland real estate investment
trust ('Equity Office Properties'), Equity Office Properties Operating Limited
Partnership, a Delaware limited partnership ('Equity Office Properties
Partnership'), Beacon Properties Corporation, a Maryland corporation
('Beacon'), and Beacon Properties, L.P., a Delaware limited partnership
('Beacon Partnership'), have on the date hereof entered into an Agreement and
Plan of Merger (the 'Merger Agreement') pursuant to which Beacon shall be
merged with and into Equity Office Properties and Beacon Partnership shall be
merged with and into Equity Office Properties Partnership (the 'Mergers');

     WHEREAS, the authorized capital stock of the Company consists of (i) one
thousand (1,000) shares, $.01 par value per share (the 'Voting Shares'), of
which nine hundred ninety (990) shares are issued and outstanding and owned by
the Stockholders as set forth on Exhibit A and ten (10) shares of which are
issued and outstanding and owned by Beacon Partnership, and (ii) one thousand
(1,000 ) shares of non voting stock, $.01 par value per share, of which one
thousand (1,000) shares are issued and outstanding and owned by Beacon
Partnership; and

     WHEREAS, as an inducement to Equity Office Properties and Equity Office
Properties Partnership to enter into the Merger Agreement, the Stockholders
have agreed to sell all of the outstanding Voting Shares held by them to
Purchaser.

     NOW, THEREFORE, in consideration of the premises and for other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

                                  ARTICLE 1

                              SALE AND PURCHASE

     1.1 Sale of Voting Shares.  Subject to, and in consideration of, the terms
and conditions of this Agreement, at the Closing (as defined in Article 2),
each Stockholder shall sell, and Purchaser shall purchase, all right, title and
interest of such Stockholder in the Voting Shares set forth opposite such
Stockholder's







name on Exhibit A.  At the Closing, each Stockholder shall deliver or cause to
be delivered to Purchaser, stock certificates representing the Voting Shares
set forth opposite such Stockholder's name on Exhibit A, duly endorsed in blank
or accompanied by stock powers duly executed in blank, in proper form for
transfer, with all appropriate stock transfer tax stamps affixed.

     1.2 Purchase Price; Delivery.  In consideration of the sale, assignment,
transfer, conveyance and delivery described above, at the Closing Purchaser
will pay each Stockholder in immediately available funds an amount equal to (i)
the number of Voting Shares set forth opposite such Stockholder's name on
Exhibit A hereto, multiplied by (ii) the fair market value per Voting Share as
determined by the parties hereto (or, if the parties are unable to so agree,
based upon an appraisal by an independent appraiser unaffiliated with any party
hereto in a manner consistent with industry practice).

                                  ARTICLE 2

                                   CLOSING

     2.1 Closing; Closing Date.  Subject to the satisfaction or waiver of the
conditions set forth in Article 5, the closing of the sale and purchase of the
Voting Shares (the 'Closing') shall take place on the same date, and at the
same time and place, as the closing under the Merger Agreement, or at such
other time and place as shall be agreed upon by the parties.  The time and date
of the Closing shall be referred to as the 'Closing Date.'

                                  ARTICLE 3

                       REPRESENTATIONS AND WARRANTIES

     3.1 Representations and Warranties of Stockholders.   Each Stockholder
represents and warrants to Purchaser as to itself or himself as follows:

     (a) Title.  Such Stockholder is, and on the Closing Date will be, the
beneficial and record owner of the Voting Shares set forth opposite such
Stockholder's name on Exhibit A, free and clear of all pledges, liens,
encumbrances, restrictions, voting agreements or trusts, rights, claims or
charges of any nature or kind whatsoever (collectively, 'Claims').  Upon
delivery to Purchaser of the certificate or certificates representing such
Voting Shares duly endorsed in blank for transfer or with stock powers attached
duly executed in blank, against delivery of the Purchase Price, good and valid
title to such Voting Shares shall be transferred to Purchaser free and clear of
any and all Claims.

     (b) Capacity.  Such Stockholder has full legal right, capacity, authority
and power to execute and deliver this Agreement and to consummate the
transactions contemplated hereby.

     (c) Binding Obligation.  This Agreement has been duly executed and
delivered by such Stockholder and constitutes such Stockholder's legal, valid
and binding obligation, 

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enforceable against such Stockholder in accordance with and subject to its
terms, subject to applicable bankruptcy, insolvency, moratorium or other
similar laws relating to creditors' rights and general principles of equity.

     (d) Non-Contravention.  Neither the execution and delivery by such
Stockholder of this Agreement nor the consummation by such Stockholder of the
transactions contemplated hereby conflict with, or result in any breach of,
constitute a default under, permit the termination of, or result in the
acceleration of any indebtedness under, any agreement, contract, lease,
promissory note, indenture, covenant or other arrangement to which such
Stockholder is a party or by which such Stockholder is, or such Stockholder's
assets are, bound.

     3.2 Representations and Warranties of Purchaser.  Purchaser represents and
warrants to each Stockholder as follows:

     (a) Organization and Standing.  Purchaser (i) is a corporation duly
organized, validly existing and in good standing under the laws of the State of
Delaware, (ii) has the full and unrestricted corporate power and corporate
authority to execute and deliver this Agreement and to consummate the
transactions contemplated hereby and (iii) has the full and unrestricted
corporate power and authority to own, operate and lease its properties and to
carry on its business.

     (b) Authorization.  The execution and delivery of this Agreement by
Purchaser, and the consummation by Purchaser of the transactions contemplated
hereby, have been duly and validly authorized by all necessary corporate or
other action on the part of Purchaser.

     (c) Binding Obligation.  This Agreement has been duly executed and
delivered by Purchaser and constitutes Purchaser's legal, valid and binding
obligation, enforceable against Purchaser in accordance with and subject to its
terms, subject to applicable bankruptcy, insolvency, moratorium or other
similar laws relating to creditors' rights and general principles of equity.

     (d) Non-Contravention.  Neither the execution and delivery by Purchaser of
this Agreement nor the consummation by Purchaser of the transactions
contemplated hereby conflict with, or result in any breach of, constitute a
default under, permit the termination of, or result in the acceleration of any
indebtedness under, any agreement, contract, lease, promissory note, indenture,
covenant or other arrangement to which Purchaser is a party or by which it is,
or its assets are, bound.

     (e) Purchase of Voting Shares.  Purchaser is purchasing the Voting Shares
for its own account and not with a view toward, or for resale in connection
with, any distribution thereof.

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                                  ARTICLE 4

                                  COVENANTS

     4.1 Filings under HSR Act.  Purchaser and each Stockholder shall use all
reasonable best efforts to cooperate with one another in determining, no later
than ten (10) days from the date hereof whether any filings are required under
the HSR Act in connection with this Agreement, and as soon as practicable upon
making any determination that such filings are required, and in any event
within fifteen (15) days after making such determination, shall make all
necessary filings under the HSR Act and shall cooperate in attempts to secure
early termination of the applicable waiting period.

     4.2 Conduct of Company Business.  From and after the date hereof, no
Stockholder shall take any action, the result of which would be to cause the
Company to conduct its business other than in the ordinary course consistent
with past practice (including, without limitation, the declaration, setting
aside or payment of any dividend or distribution with respect to the Company's
capital stock).  Without limiting the generality of the foregoing, no
Stockholder shall approve (i) the issuance by the Company of any capital stock
or any options, warrants or other rights to subscribe for or purchase any of
the Company's capital stock or any securities convertible into or exchangeable
for the Company's capital stock, (ii) the direct or indirect redemption,
purchase or other acquisition of any of the Company's capital stock, (iii) a
split, reclassification or other change in or of any of the Company's capital
stock, or (iv) any amendment of the Company's articles of incorporation or
bylaws.

     4.3 Additional Actions and Documents.  Each of the parties hereby agrees
to take or cause to be taken such further actions and to execute, deliver and
file or cause to be executed, delivered and filed, such further documents as
may be necessary or as may be reasonably requested in order to fully effectuate
the purposes, terms and conditions of this Agreement.

                                  ARTICLE 5

                            CONDITIONS TO CLOSING

     5.1 Conditions to the Obligations of Purchaser.  The obligations of
Purchaser under this Agreement are subject to the fulfillment, at or prior to
the Closing, of each of the following conditions:

     (a) The representations and warranties made by each of the Stockholders in
this Agreement shall be true and correct when made, and on and as of the
Closing Date as though such representations and warranties were made on and as
of the Closing Date.

     (b) Each Stockholder shall have performed and complied with all covenants
and conditions required by this Agreement to be performed or complied with by
it or him or all one or more Stockholders collectively prior to the Closing
Date.

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     (c) No action or proceeding by or before any governmental authority shall
have been instituted or threatened (and not subsequently settled, dismissed or
otherwise terminated) which is reasonably expected to restrain, prohibit or
invalidate the transactions contemplated by this Agreement other than an action
or proceeding instituted or threatened by Purchaser.

     (d) Each Stockholder shall have delivered to Purchaser a certificate,
dated as of the Closing Date and executed by such Stockholder, certifying, as
to such Stockholder, the fulfillment of the conditions specified in Sections
5.1(a) and (b).

     (e) Any and all applicable waiting periods under the HSR Act shall have
expired.

     (f) Each of the parties to the Merger Agreement shall have certified to
Purchaser that all conditions to the closing of the transactions thereunder
have been waived or satisfied.

     5.2 Conditions to the Obligations of each Stockholder.  The obligations of
each Stockholder under this Agreement are subject to the fulfillment, at or
prior to the Closing, of each of the following conditions:

     (a) The representations and warranties made by Purchaser in this Agreement
shall be true and correct when made, and on and as of the Closing Date as
though such representations and warranties were made on and as of the Closing
Date.

     (b) Purchaser shall have performed and complied with all covenants and
conditions required by this Agreement to be performed or complied with by it
prior to the Closing Date.

     (c) No action or proceeding by or before any governmental authority shall
have been instituted or threatened (and not subsequently settled, dismissed or
otherwise terminated) which is reasonably expected to restrain, prohibit or
invalidate the transactions contemplated by this Agreement other than an action
or proceeding instituted or threatened by one or more of the Company or one or 
more Stockholders.

     (d) Purchaser shall have delivered to the Stockholders a certificate,
dated as of the Closing Date and executed by Purchaser, certifying, as to such
Stockholder, the fulfillment of the conditions specified in Sections 5.2 (a)
and (b).

     (e) Any and all applicable waiting periods under the HSR Act shall have
expired.

     (f) Each of the parties to the Merger Agreement shall have certified to
the Stockholders that all conditions to the closing of the transactions
thereunder have been waived or satisfied.

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                                  ARTICLE 6

                                 TERMINATION

     6.1   Events of Termination.  (a) This Agreement may be terminated at any
time before the Closing Date under any one or more of the following
circumstances:

     (i)   by the mutual written consent of all of the parties hereto;

     (ii)  by Purchaser, if any Stockholder shall have breached, or failed to
comply with, in any material respect any of its or his respective obligations
under this Agreement or any representation or warranty made by it or him shall
have been incorrect when made or shall have since ceased to be true and
correct;

     (iii) by the Stockholders, if Purchaser shall have breached, or failed to
comply with, in any material respect any of its obligations under this
Agreement or any representation or warranty made by Purchaser shall have been
incorrect when made or shall have since ceased to be true and correct; or

     (iv)  by Purchaser or the Stockholders, if any decree, permanent
injunction, judgment, order or other action by any court of competent
jurisdiction or any governmental or regulatory authority preventing or
prohibiting consummation of the transactions contemplated hereby shall have
become final and non-appealable.

     (b)   This Agreement shall terminate immediately upon the termination of 
the Merger Agreement.

     6.2   Effect of Termination.  In the event this Agreement is terminated as
provided in this Article 6, this Agreement shall forthwith become wholly
void and of no effect, and the parties shall be released from all future
obligations hereunder, except that the provisions of Section 7.4 (Governing
Law) shall survive the termination of this Agreement; provided, however, that
nothing herein shall relieve any party for any material breach of any of its or
his representations, warranties, covenants or agreements under this Agreement.

                                  ARTICLE 7

                                MISCELLANEOUS

     7.1   Descriptive Headings.  The descriptive headings herein are inserted
for convenience only and are not intended to be part of or to affect the
meaning or interpretation of this Agreement.

     7.2   Counterparts.  This Agreement may be executed in counterparts, each 
of which when so executed and delivered shall be an original, but all of such
counterparts shall together constitute one and the same instrument.


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     7.3 Entire Agreement; Assignment.  This Agreement (i) constitutes the
entire agreement and supersedes all prior agreements and understandings, both
written and oral, among the parties hereto with respect to the subject matter
hereof and (ii) shall not be assigned by any party hereto by operation of law
or otherwise, without the prior written consent of each other party hereto;
provided, however, that Purchaser may assign this Agreement without consent of
the Stockholders to any affiliate of Purchaser.

     7.4 Governing Law.  THIS AGREEMENT SHALL BE GOVERNED BY AND CONSTRUED IN
ACCORDANCE WITH THE LAWS OF THE STATE OF MARYLAND WITHOUT REGARD TO THE
PRINCIPLES OF CONFLICTS OF LAWS THEREOF.

     7.5 Specific Performance.  The parties hereto agree that if any of the
provisions of this Agreement were not performed in accordance with their
specific terms or were otherwise breached, irreparable damage would occur, no
adequate remedy at law would exist and damages would be difficult to determine,
and that the parties shall be entitled to specific performance of the terms
hereof, in addition to any other remedy at law or equity.

     7.6 Parties in Interest.  This Agreement shall be binding upon and inure
solely to the benefit of each party hereto, and nothing in this Agreement,
express or implied, is intended to or shall confer upon any other person or
persons any rights, benefits or remedies of any nature whatsoever under or by
reason of this Agreement.

     7.7 Amendment; Waivers.  This Agreement shall not be amended, altered or
modified except by an instrument in writing duly executed by each of the
parties hereto.  No delay or failure on the part of any party hereto in
exercising any right, power or privilege under this Agreement shall impair any
such right, power or privilege or be construed as a waiver of any default or
any acquiescence thereto.  No single or partial exercise of any such right,
power or privilege shall preclude the further exercise of such right, power or
privilege, or the exercise of any other right, power or privilege.  No waiver
shall be valid against any party hereto, unless made in writing and signed by
the party against whom enforcement of such waiver is sought, and then only to
the extent expressly specified therein.


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     IN WITNESS WHEREOF, the parties have executed this Agreement on the date
first above written.

                                           EQUITY OFFICE PROPERTIES MANAGEMENT
                                           CORP.


                                           By: /s/ Stanley M. Stevens
                                              --------------------------------
                                           Name: Stanley M. Stevens
                                           Title: V.P.

Stockholders:


/s/ Norman B. Leventhal, Trustee
--------------------------------
Name: Norman B. Leventhal, as
      Voting Trustee u/t/a dated
      March 6, 1989




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                                                                      Exhibit A






Name of Stockholder      Number of Voting Shares
--------------------     -----------------------
                      
Norman B. Leventhal,                    990
as Voting Trustee u/t/a
dated March 6, 1989