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                                                                   Exhibit 10.21


                         AGREEMENT OF PURCHASE AND SALE

                                 BY AND BETWEEN

                           ROBERT MARTIN COMPANY, LLC

                                       AND

                       MACK-CALI REALTY ACQUISITION CORP.

                             DATED AS OF MAY 1, 2002

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                         AGREEMENT OF PURCHASE AND SALE


         THIS AGREEMENT OF PURCHASE AND SALE (this "AGREEMENT") is made as of
this 1st day of May, 2002 (the "Effective Date"), by and between ROBERT MARTIN
COMPANY, L.L.C., a New York limited liability company having an address at 100
Clearbrook Road, Elmsford, New York 10523 ("RMC ") and MACK-CALI REALTY
ACQUISITION CORP., a Delaware corporation having an address c/o Mack-Cali Realty
Corporation, 11 Commerce Drive, Cranford, New Jersey 07016 ("MACK-CALI").

                              W I T N E S S E T H:

         WHEREAS, RMC desires to sell, and Mack-Cali desires to purchase, all of
RMC's right, title and interest in and to the Property (as hereinafter defined),
subject to the terms and conditions set forth herein.

         NOW, THEREFORE, in consideration of the mutual promises set forth
herein and other good and valuable consideration, the receipt and sufficiency of
which are hereby acknowledged, the parties hereto agree as follows:

1.       SUBJECT OF THE SALE AND PURCHASE

         Subject to the terms and conditions set forth in this Agreement, RMC
hereby agrees to sell, and Mack-Cali hereby agrees to purchase, all of RMC's
right, title and interest in and to the following:

             (a)   The real property consisting of approximately 118,387 square
                   feet as shown on the site plan entitled "SWEP- 250 Corp.
                   Blvd. South Approximate Property Line" attached hereto as
                   Exhibit A (the "REAL PROPERTY"). A legal description of the
                   Real Property shall be prepared by the surveyor preparing a
                   survey of the Real Property for Mack-Cali (as provided in
                   Section 3.1(d) hereof);

             (b)   all buildings, structures, fixtures, parking areas and other
                   improvements located on the Real Property (the
                   "IMPROVEMENTS");

             (c)   any and all easements, rights of way, strips and gores of
                   land, streets, ways, alleys, passages, sewer rights, water,
                   water courses, water rights and powers, air rights and
                   development rights, and all estates, rights, titles,
                   interests, privileges, liberties, tenements, hereditaments
                   and appurtenances

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                   of any nature whatsoever, in any way belonging, relating or
                   pertaining to the Real Property and all land lying in the bed
                   of any street, road or avenue, opened or proposed, in front
                   of or adjoining the Real Property, to the center line thereof
                   (collectively, the "EASEMENTS");

             (d)   any and all approvals, permits, licenses and agreements,
                   including but not limited to environmental permits,
                   subdivision approvals, development agreements, site plans and
                   approvals relating to the development and use of the Real
                   Property, and specifically including any and all plans,
                   specifications, architectural and engineering drawings,
                   warranties, and guaranties held by RMC (collectively, the
                   "PERMITS AND LICENSES"), and any and all contracts and
                   agreements for the servicing and maintenance of the Real
                   Property (collectively, the "SERVICE CONTRACTS", together
                   with the Permits and Licenses, the "INTANGIBLE PROPERTY");

             (e)   any and all trademarks and tradenames used or useful in
                   connection with the Real Property (including but not limited
                   to any other name[s] by which the Property is commonly known)
                   and all goodwill, if any, related to said names, all for
                   which Mack-Cali shall have the sole and exclusive rights
                   (collectively, the "TRADENAMES");

             (f)   any and all promotional materials, marketing materials,
                   brochures, photographs (collectively, the "PROMOTIONAL
                   MATERIALS"), books, records, files, statements, tax returns,
                   market studies, plans, specifications, reports, tests and
                   other materials of any kind owned by or in the possession of
                   RMC which are or may be used by RMC in the development and
                   use of the Real Property (collectively, and together with the
                   Promotional Materials, the "BOOKS AND RECORDS");

             (g)   any and all awards or payments, including interest thereon,
                   which may heretofore and hereafter be made with respect to
                   the Real Property, whether from the exercise of the right of
                   eminent domain or for a change of grade or for any other
                   injury to or decrease in the value of the Real Property; and

             (h)   all other rights, interests and privileges (if any) held by
                   RMC in any way related to the rights and interests described
                   above in this Section.

         The Real Property, Improvements, Easements, the Intangible Property,
the Tradenames, the Books and Records, and all other interests in the Real
Property held by RMC, shall hereinafter be collectively referred to as the
("PROPERTY").

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2.       CONSIDERATION FOR THE PURCHASE AND SALE

         2.1       As consideration for the assignment (the "CONSIDERATION"),
Mack-Cali shall pay to RMC on the Closing Date (as defined in Section 8.1) the
amount of One Million ($1,000,000.00) Dollars. The Consideration shall be paid
by the wiring of federal funds to such bank account as RMC shall designate in
writing at least two (2) business days prior to the Closing Date.

3.       TITLE MATTERS TO WHICH THE REAL PROPERTY IS SUBJECT

         3.1       The Property shall be sold to Mack-Cali subject to the
following (collectively, the "PERMITTED ENCUMBRANCES"):

                   (a) the lien of real estate taxes, personal property taxes,
water charges, and sewer charges, provided the same are not due and payable, but
subject to adjustment as provided herein;

                   (b) those restrictions, covenants, agreements, easements, and
other matters affecting title to the Property as set forth in the Title
Commitment (as defined in Section 3.2), provided same do not impair the use of
the Property as intended by Mack-Cali and do not render the fee interest
uninsurable at standard rates;

                   (c) any and all laws, statutes, ordinances, codes, rules,
regulations, requirements, or executive mandates affecting the Property as of
the date hereof, except for engineering or institutional controls (including,
without limitation, a deed notice or declaration of environmental restrictions,
a groundwater classification exception area, or well restriction area) affecting
the Property; and

                   (d) the state of facts which a survey of the Property would
actually show (said survey to be ordered by Mack-Cali at its sole cost and
expense), provided such state of facts do not impair the use of the Property as
intended by Mack-Cali and do not render the fee interest uninsurable at standard
rates.

         3.2       Mack-Cali shall cause any title company licensed to do
business in the State of New York (the "TITLE COMPANY") to prepare a title
search and commitment for a fee insurance policy (the "TITLE COMMITMENT") and
shall cause a copy of the same to be delivered to counsel for RMC. If any
defects, objections or exceptions in the title to the Property appear in the
Title Commitment (other than the Permitted Encumbrances) which Mack-Cali is not
required to accept under the terms of this Agreement, RMC agrees to use good
faith efforts to cure the same prior to the Closing, and in any event to cure,
at its expense, the following: (a) judgments against RMC, (b) mortgages and
other liens which can be satisfied by the payment of a liquidated amount, and
(c) defects, objections or exceptions which can be removed by payments not to
exceed, in the aggregate, three (3%) percent of the Consideration. RMC, in its
discretion,

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may adjourn the Closing for up to sixty (60) days in order to eliminate
unacceptable defects, objections or exceptions. If, after complying with the
foregoing requirements, RMC is unable to eliminate all unacceptable defects,
objections or exceptions in accordance with the terms of this Agreement on or
before such adjourned date for the Closing, Mack-Cali shall elect either (x) to
terminate this Agreement by notice given to the RMC, in which event the
provisions of Section 3.5 shall apply, or (y) to purchase the Property subject
to such unacceptable defects, objections or exceptions with no credit against or
reduction in the Consideration. RMC agrees and covenants that it shall not
voluntarily place any defects, objections or exceptions to title to the Property
from and after the date of the first issuance of the Title Commitment for the
Property.

         3.3       (a) It shall be a condition to Closing that RMC sell, and
that the Title Company insure, at a standard rate for such insurance, the fee
interest in the Real Property equal to the amount of the Consideration in the
name of Mack-Cali or its designees, after execution and delivery of the Deed as
defined in Section 8.2(a), by a standard fee insurance policy, with endorsements
as may be available and are required by Mack-Cali, free and clear of all liens,
encumbrances and other matters, other than the Permitted Encumbrances (the
"TITLE POLICY"). The Title Company shall provide affirmative insurance that (i)
none of the Permitted Encumbrances have been violated, and that any future
violation thereof will not result in a forfeiture or reversion of fee title,
(ii) Mack-Cali's contemplated use of the Property will not violate the Permitted
Encumbrances; and (iii) the exception for taxes shall apply only to the current
taxes not yet due and payable as of the Closing Date.

                   (b) RMC shall provide such affidavits (including title
affidavits and survey affidavits of no change) and undertakings as the Title
Company may reasonably require. In addition, if the Title Commitment discloses
judgments, bankruptcies or other returns against other persons having names the
same as or similar to that of RMC, RMC shall, upon request, deliver to the Title
Company affidavits showing that such judgments, bankruptcies or other returns
are not against RMC or any of its affiliates. Upon request by Mack-Cali, RMC
shall deliver any affidavits and documentary evidence as reasonably required by
the Title Company to eliminate the standard or general exceptions in the Title
Policy.

                   (c) The words "insurable title" and "insurable" as used in
this Agreement are hereby defined to mean title, which is insurable at standard
rates (without special premium) by the Title Company without exception other
than the Permitted Encumbrances and the standard printed policy and survey
exceptions.

         3.4       Any unpaid taxes, water charges, sewer rents and assessments,
together with the interest and penalties thereon, to a date not less than seven
(7) business days following the Closing Date (in each case subject to any
applicable apportionment), together with the cost of recording or filing of any
instruments necessary to discharge such liens and such judgments, shall be paid
at the Closing by RMC. On the Closing Date, RMC shall deliver to Mack-Cali
instruments in recordable form sufficient to discharge any liens which RMC is
obligated to pay and discharge pursuant to the terms of this Agreement.

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         3.5       If RMC is unable to convey the Property in accordance with
the terms of this Agreement, then Mack-Cali shall, as its sole and exclusive
remedy, have the right to terminate this Agreement. In such event, neither party
shall have any further rights or obligations hereunder other than those which
are expressly stated herein to survive any such termination, and RMC shall
reimburse Mack-Cali for all charges incurred by reason of (a) examining the
title to the Property, (b) any appropriate additional municipal searches made in
accordance with this Agreement, and (c) the survey and survey inspection
charges, which reimbursement obligation shall survive the termination of this
Agreement.

4.       REPRESENTATIONS AND WARRANTIES OF RMC

         4.1       In order to induce Mack-Cali to perform as required
hereunder, RMC represents and warrants the following:

                   (a) RMC is a duly organized and validly existing limited
liability company organized under the laws of the State of New York, and has all
requisite power and authority to execute and deliver this Agreement and all
other documents and instruments to be executed and delivered by it hereunder,
and to perform its obligations hereunder and under such other documents and
instruments in order to convey the Property in accordance with the terms and
conditions hereof. All necessary actions of the partners of RMC to confer such
power and authority upon the person(s) executing this Agreement and all
documents, which are contemplated by this Agreement on its behalf, have been
taken.

                   (b) This Agreement, when duly executed and delivered, shall
be the legal, valid and binding obligation of RMC, enforceable in accordance
with the terms of this Agreement. The performance by RMC of its duties and
obligations under this Agreement and the documents and instruments to be
executed and delivered by it hereunder will not conflict with, or result in a
breach of, or default under, any provision of any of the organizational
documents of RMC or any agreements, instruments, decrees, judgments,
injunctions, orders, writs, laws, rules or regulations, or any determination or
award of any court or arbitrator to which RMC is a party or by which its assets
are or may be bound.

                   (c) To RMC's knowledge, no condition exists which, with the
passage of time or the giving of notice or both, shall become a violation of
law. As of the date hereof, there are no leases, tenancy or occupancy agreements
affecting the Property, and there are no other agreements which confer upon any
tenant or any other person or entity any rights with respect to the Property.

                   (d) As of the date hereof, no work has been performed (by, or
by direction of RMC) at the Property which would require an amendment or any
other change to the Permit and Licenses, and any and all work which may be
performed at the Property from the date hereof to the Closing Date shall be in
accordance with the rules, laws and regulations of all applicable authorities.
Any bills and claims for labor performed and materials furnished to or for the
benefit

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of the Property (by, or under the direction of RMC) shall be paid in full by RMC
on the Closing Date.

                   (e) There are, to RMC's knowledge, no service contracts,
union contracts, employment agreements or other agreements affecting the
Property or the operation thereof except as disclosed on SCHEDULE 4.1(c).

                   (f) The Permits and Licenses include all
certificates, licenses, permits and authorizations (including, without
limitation, any Permits and Licenses relating to any environmental matters)
necessary to properly subdivide and improve the Property and to operate and use
said improvements, all of which Permits and Licenses are listed on SCHEDULE
4.1(f), along with the expiration dates of the same. RMC has not received any
notice that any of the Permits and Licenses are subject to, or in jeopardy of,
revocation or non-renewal. RMC is current in the payment of any fees required to
be paid for the Permits and Licenses. All Permits and Licenses are in full force
and effect; are transferable without additional payment by Mack-Cali; and shall,
at Closing, be transferred to Mack-Cali by RMC.

                   (g) There are, to the knowledge of RMC, no actions, suits,
labor disputes, litigation or proceedings currently pending or threatened
against or related to RMC or to all or any part of the Property, the
environmental condition thereof, or the operation thereof, nor does RMC know of
any basis for any such action.

                   (h) To RMC's knowledge, there are no outstanding requirements
or recommendations by (i) the insurance company(s) currently insuring the
Property; (ii) any board of fire underwriters or other body exercising similar
functions, or (iii) the holder of any mortgage encumbering any of the Property,
which require or recommend any repairs or work to be done on the Property.

                   (i) RMC has received no written notice and has no knowledge
of (i) any pending or contemplated annexation or condemnation proceedings, or
private purchase in lieu thereof, affecting or which may affect the Property or
any part thereof, (ii) any proposed or pending proceeding to change or redefine
the zoning classification of all or any part of the Property, (iii) any proposed
or pending special assessments affecting the Property or any portion thereof,
(iv) any penalties or interest due with respect to real estate taxes assessed
against the Property, and (v) any proposed change(s) in any road or grades with
respect to the roads providing a means of ingress and egress to the Property.
RMC agrees to furnish Mack-Cali with a copy of any such notice received within
two (2) business days after its receipt.

                   (j) RMC has provided Mack-Cali with all reports, including,
without limitation, the Environmental Documents as defined in Section
4.2(b)(iv), in RMC's possession or under its control related to the physical
condition of the Property.

                   (k) RMC has no knowledge of any violations or any notices,
suits, investigations or judgments relating to any violations of any laws,
ordinances or regulations (including, without limitation, Environmental Laws as
defined in Section 4.2(b)(v)) affecting the

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Property, or any violations or conditions which may give rise thereto, and has
no reason to believe that any agency, board, bureau, commission, department,
office or body of any municipal, county, state or federal governmental unit, or
any subdivision thereof, having, asserting or acquiring jurisdiction over all or
any part of the Property or the management, operation, use or improvement
thereof (collectively, the "GOVERNMENTAL AUTHORITIES") contemplates the issuance
thereof, and to RMC's knowledge, there are no outstanding orders, judgments,
injunctions, decrees, directives or writs of any Governmental Authorities
against or involving RMC or the Property.

                   (l) There are no employees of RMC working at or in connection
with the Property or union agreements affecting the Property as of the date
hereof, nor shall any such agreements affect the Property as of the Closing
Date.

                   (m) There are no obligations in the nature of a leasing
commission due and owing from RMC with respect to the Property or any leases
related thereto.

                   (n) RMC has not made a general assignment for the benefit of
creditors, filed any voluntary petition in bankruptcy or suffered the filing of
any involuntary petition by RMC's creditors, suffered the appointment of a
receiver to take possession of all or substantially all of RMC's assets,
suffered the attachment or other judicial seizure of all or substantially all of
RMC's assets, admitted in writing its inability to pay its debts as they come
due or made an offer of settlement, extension or composition to its creditors
generally.

                   (o) To RMC's knowledge, there are no engineering or
institutional controls at the Property designed to address the Discharge of
Contaminants (both terms as defined in Section 4.2(b)) at the Property or
required by Environmental Laws or Governmental Authorities, including without
limitation any deed notice, declaration of environmental restriction,
groundwater classification exception area, well restriction area or other notice
or use limitations pursuant to Environmental Laws.

                   (p) RMC has no knowledge that any part of the Property has
been designated as wetlands under the Federal Water Pollution Control Act, 33
U.S.C. Section 1251 ET SEQ., the Freshwater Wetlands Act, N.Y. Envtl. Conserv.
Law, Section 24-0101 ET SEQ., the Tidal Wetlands Act, N.Y. Envtl. Conserv. Law
Section 25-0101, or any applicable local law or regulation promulgated pursuant
to any of the foregoing.

                   (q) RMC does not own or operate any property which any
Governmental Authority has demanded, in writing addressed to and received by RMC
or any of its affiliates, counsel or agents, be cleaned up and which has not
been cleaned up.

                   (r) RMC has paid all Taxes (as hereinafter defined) due and
payable prior to the Closing, and has filed all returns and reports, if any,
required to be filed prior to the Closing for which Mack-Cali could be held
liable. There are no audits or other proceedings by any Governmental Authorities
pending or to RMC's knowledge, threatened with respect to the Taxes for which
Mack-Cali could be held liable. No assessment of Taxes is proposed against RMC

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(including any predecessor entities) or the Property. RMC is not party to, and
has no liability under (including liability with respect to a predecessor
entity) any indemnification, allocation or sharing agreement with respect to
Taxes. "TAXES" shall mean all federal, state, county, local, foreign and other
taxes of any kind whatsoever (including, without limitation, income, profits,
premium, estimated, excise, sales, use, occupancy, gross receipts, franchise, ad
valorem, severance, capital levy, production, transfer, license, stamp,
environmental, withholding, employment, unemployment compensation, payroll
related and property taxes, import duties and other governmental charges or
assessments), whether or not measured in whole or in part by net income, and
shall include (i) deficiencies, interest, additions to tax or interest, and
penalties with respect thereto, and (ii) expenses associated with contesting any
proposed adjustment related to any of the foregoing.

                   (s) There are no proceedings presently pending for a
reduction in the assessed valuation of the Property, and no such proceeding
shall be commenced or settled by RMC without Mack-Cali's prior written consent.

                   (t) No representation or warranty made by RMC contained in
this Agreement, and no statement contained in any document, certificate,
Schedule or Exhibit furnished or to be furnished by, or on behalf of, RMC to
Mack-Cali or any of Mack-Cali's designees or affiliates pursuant to this
Agreement contains or will contain any untrue statement of a material fact or
omits or will omit to state any material fact necessary, in light of the
circumstances under which it was or will be made, in order to make the
statements herein or therein not misleading or necessary in order to fully and
fairly provide the information required to be provided in any such document,
certificate, Schedule or Exhibit.

         4.2       In addition to the provisions of Section 4.1, RMC hereby
represents and warrants the following with respect to environmental matters:

                   (a) Except as disclosed on SCHEDULE 4.2(a):

                       (i)      To RMC's knowledge, there are no Contaminants
on, under, at, emanating from or affecting the Property, which would allow a
Governmental Authority to demand that a cleanup be undertaken;

                       (ii)     To RMC's knowledge, it has not received any
Section 104(e) informational request issued pursuant to the Comprehensive
Environmental Response, Compensation and Liability Act, as amended, 42 U.S.C.
Section 9601 ET SEQ.;

                       (iii)    To RMC's knowledge, there is no asbestos or
asbestos containing material on the Property requiring remediation under
Environmental Laws;

                       (iv)     To RMC's knowledge, all pre-existing
above-ground storage tanks and Underground Storage Tanks and vessels, if any, at
the Property have been removed and their contents disposed of in accordance with
and pursuant to all applicable Environmental Laws;

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                       (v)      To RMC's knowledge, the Property has not been
used as a solid waste management facility as defined in the New York
Environmental Conservation Law ("ECL") Section 27-0701 ET SEQ.;

                       (vi)     To RMC's knowledge, RMC has all required
environmental certificates, licenses and permits (collectively, "PERMITS"), and
there is no violation of any statute, ordinance, rule, regulation, order, code,
directive or requirement (including, without limitation, Environmental Laws)
with respect to any Permit or any pending application for any Permit;

                       (vii)    RMC has not and shall not knowingly permit any
person or entity to engage in any activity on the Property in violation of
Environmental Laws; and

                       (viii)   To RMC's knowledge, the Property is in material
compliance with Environmental Laws.

                   (b) The following terms shall have the following meanings
when used in this Agreement:

                       (i)      "CONTAMINANTS" shall include, without
limitation, any regulated substance, toxic substance, hazardous substance,
hazardous waste, pollution, pollutant or contaminant, as defined or referred to
in the Tank Laws (as defined below); the ECL; the New York State Navigation Law;
the Resource Conservation and Recovery Act, as amended, 42 U.S.C. Section 6901
ET SEQ.; the Comprehensive Environmental Response, Compensation and Liability
Act, as amended, 42 U.S.C. Section 9601 ET SEQ.; and the Water Pollution and
Control Act, 33 U.S.C. Section 1251 ET SEQ.; together with any amendments
thereto, regulations promulgated thereunder and all substitutions thereof, as
well as words of similar purport or meaning referred to in any other applicable
federal, state, county or municipal environmental statute, ordinance, code, rule
or regulation, including, without limitation, radon, lead, asbestos,
polychlorinated biphenyls, urea formaldehyde and petroleum products and
petroleum-based derivatives.

                       (ii)     "DISCHARGE" shall mean the releasing, spilling,
leaking, leaching, disposing, pumping, pouring, emitting, emptying, treating or
dumping of Contaminants at, into, onto or migrating from or onto the Property,
regardless of whether the result of an intentional or unintentional action or
omission.

                       (iii)    "DEC" shall mean the New York Department of
Environmental Conservation or its successor.

                       (iv)     "ENVIRONMENTAL DOCUMENTS" shall mean all
environmental documentation in the possession or under the control of RMC
concerning the Property, or its environs, including without limitation, all
sampling plans, cleanup plans, preliminary assessment plans and reports, site
investigation plans and reports, remedial investigation plans and reports,
remedial action plans and reports, or the equivalent, sampling results, sampling
result reports, data, diagrams, charts, maps, analysis, conclusions, quality
assurance/quality control documentation, correspondence to or from any
Governmental Authority, submissions to any Governmental

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Authority and directives, orders, approvals and disapprovals issued by any
Governmental Authority.

                       (v)      "ENVIRONMENTAL LAWS" shall mean each and every
applicable federal, state, county or municipal statute, ordinance, rule,
regulation, order, code, directive or requirement of any Governmental Authority
in any way related to Contaminants.

                       (vi)     "GOVERNMENTAL AUTHORITY" shall mean the federal,
state, county or municipal government, or any department, agency, bureau or
other similar type body obtaining authority therefrom, or created pursuant to
any law.

                       (vii)    "NOTICE" shall mean, in addition to its ordinary
meaning, any written communication of any nature, whether in the form of
correspondence, memoranda, order, directive or otherwise.

                       (viii)   "TANK LAWS" shall mean the New York Bulk Storage
Law, ECL Section 17-1743, the New York Hazardous Substances Bulk Storage Act,
ECL Section 40-0101 ET SEQ., and the federal Underground Storage Tank Law
(Subtitle I) of the Resource Conservation and Recovery Act, as amended, 42
U.S.C. Section 6901 ET SEQ., together with any amendments thereto, regulations
promulgated thereunder, and all substitutions thereof, and any successor
legislation and regulations.

                       (ix)     "UNDERGROUND STORAGE TANK" shall mean each and
every "underground storage tank," whether or not subject to the Tank Laws, as
well as the "monitoring system," the "leak detection system," the "discharge
detection system" and the "tank system" associated with the "underground storage
tank," as those terms are defined by the Tank Laws.

         4.3       All representations and warranties made by RMC in this
Agreement shall not be merged in the execution and delivery of the Deed and
shall instead survive the Closing Date for a period of one (1) year. RMC agrees
to indemnify and defend and to hold Mack-Cali harmless from and against any and
all claims, liabilities, losses, deficiencies, and damages, as well as
reasonable expenses (including attorneys, consulting and engineering fees), and
interest and penalties related thereto, incurred by Mack-Cali by reason of or
resulting from any breach, inaccuracy, incompleteness or nonfulfillment of the
representations, warranties, covenants and agreements of RMC contained in this
Agreement. In no event shall RMC's liability on account of a failure of a
representation or warranty exceed $250,000 in the aggregate, unless the same
results from the gross negligence or willful misconduct of RMC. In addition,
Mack-Cali shall not be entitled to make a claim against RMC from and after the
Closing if any senior executive officer of Mack-Cali or its affiliates had
actual knowledge of the matter which is the subject of the failure of such
representation or warranty.

         4.4       Mack-Cali acknowledges and agrees that, except as provided in
this Agreement, RMC has not made any representations or warranties of any kind
or character whatsoever, whether express or implied, with respect to the
Property and that, except as provided in this Agreement, Mack-Cali accepts the
Property in its "AS IS" condition. Mack-Cali acknowledges that it is not in a
significantly disparate bargaining position with respect to RMC in connection

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with the transaction contemplated by this Agreement and that Mack-Cali was
represented by legal counsel in connection with this transaction.

5.       REPRESENTATIONS AND WARRANTIES OF MACK-CALI

         5.1       In order to induce RMC to perform as required hereunder,
Mack-Cali hereby warrants and represents the following:

                   (a) Mack-Cali is a duly organized and validly existing
corporation organized under the laws of the State of Delaware and is authorized
to do business in the State of New York, has all requisite power and authority
to execute and deliver this Agreement and all other documents and instruments to
be executed and delivered by it hereunder, and to perform its obligations
hereunder and under such other documents and instruments in order to purchase
the Property in accordance with the terms and conditions hereof. All necessary
actions of Mack-Cali to confer such power and authority upon the person(s)
executing this Agreement and all documents, which are contemplated by this
Agreement on its behalf, have been taken.

                   (b) This Agreement, when duly executed and delivered, will be
the legal, valid and binding obligation of Mack-Cali, enforceable in accordance
with the terms of this Agreement. The performance by Mack-Cali of its duties and
obligations under this Agreement and the documents and instruments to be
executed and delivered by it hereunder will not conflict with, or result in a
breach of, or default under, any provision of any of the organizational
documents of Mack-Cali or any agreements, instruments, decrees, judgments,
injunctions, orders, writs, laws, rules or regulations, or any determination or
award of any court or arbitrator, to which Mack-Cali is a party or by which its
assets are or may be bound.

         5.2       All representations and warranties made by Mack-Cali in this
Agreement shall not be merged in the delivery of the Deed and shall survive the
Closing Date for a period of one (1) year. From and after the Closing, Mack-Cali
agrees to indemnify and defend RMC, and to hold RMC harmless, from and against
any and all claims, liabilities, losses, deficiencies and damages as well as
reasonable expenses (including attorney's, consulting and engineering and other
professional and expert fees), and interest and penalties related thereto,
incurred by RMC, by reason of or resulting from any breach, inaccuracy,
incompleteness or nonfulfillment of the representations, warranties, covenants
and agreements of Mack-Cali contained in this Agreement.

         5.3       RMC acknowledges that it is not in a significantly disparate
bargaining position with respect to Mack-Cali in connection with the transaction
contemplated by this Agreement and that RMC was represented by legal counsel in
connection with this transaction.

6.       COVENANTS OF RMC

         6.1       RMC covenants and agrees that between the date hereof and the
Closing Date, it

                                       11
<Page>

shall perform or observe the following:

                   (a) RMC shall not defer taking any actions or spending any of
its funds or otherwise manage the Property differently (other than in the
ordinary course of business) on account of the pending sale to Mack-Cali.

                   (b) RMC shall, at its sole cost and expense and in a manner
reasonably satisfactory to Mack-Cali, take such action as may be necessary
(including but not limited to subdivision of the Land) to cause the Property to
be assessed as a separate tax lot. Notwithstanding anything to the contrary in
this Agreement, in the event that subdivision of the Land shall be required so
to cause the Property to be assessed as a separate tax lot, RMC shall (i) bear
the cost of the survey of the Property, (ii) cause the surveyor to update the
survey as of the Closing Date, and (iii) have the general survey exception
removed from the Title Policy and the survey affirmatively insured to Mack-Cali.

                   (c) RMC shall not cause or permit its interest in the
Property to be alienated, mortgaged, licensed, encumbered or otherwise
transferred.

                   (d) RMC shall make all required payments under any mortgage
affecting its interest in the Property within any applicable grace period but
without reimbursement by Mack-Cali therefor.

                   (e) Up to and including the Closing Date, RMC shall maintain
and keep such hazard, liability and casualty insurance policies in full force
and effect in such amounts and covering such risks sufficiently to protect the
Property and to protect, to a reasonable and prudent extent, the owner of the
Property, in such amounts as are required so as not to be deemed a co-insurer,
and for actual replacement cost, against any loss, damage, claim or liability.

                   (f) All violations of statutes, ordinances, rules,
regulations, orders, codes, directives or requirements affecting the Property,
whether or not such violations are now noted in the records of or have been
issued by any Governmental Authorities (other than those caused by the actions
of Mack-Cali or its employees, affiliates or agents or the employees or agents
of its affiliates) shall be complied with by RMC prior to the Closing, and RMC's
interest in the Property shall be conveyed free of any such violations
(including, without limitation, violations of Environmental Laws).

                   (g) In addition to the foregoing, RMC shall:

                       (i)      promptly notify Mack-Cali of, and promptly
deliver to Mack-Cali, a certified true and complete copy of any Notice as
defined in Section 4.2(b)(vii) which RMC may receive, on or before the Closing
Date, from any Governmental Authority concerning a violation of Environmental
Laws or Discharge of Contaminants;

                       (ii)     contemporaneously with the signing and delivery
of this Agreement, and subsequently, promptly upon receipt by RMC or its
representatives, deliver to

                                       12
<Page>

Mack-Cali a certified true and complete copy of all Environmental Documents; and

                       (iii)    without any cost or expense to RMC, cooperate
with Mack-Cali in all reasonable respects in connection with the submission to
and approval by, the requisite municipal authorities of all plans,
specifications, designs, surveys and studies required for the construction on
the Property of the improvements contemplated by Mack-Cali, including, without
limitation, the making of such submissions in RMC's name.

                       (g) RMC and Mack-Cali shall cooperate in good faith to
enter into reciprocal easement agreements which will provide for, among other
things, shared parking, access across the other parties' property and such other
matters as the Land and the Development Sites and Real Property (as defined in
the Contribution and Exchange Agreement made the 24th day of January, 1997
between Robert Martin Company, LLC, RM Eastview, Cali Realty, L.P.and Cali
Realty Corporation) associated therewith may reasonably require for the use of
either parties' property, subject to the Development Standards (as defined in
the Contribution and Exchange Agreement). The creation of such easements shall
be deemed to include the extension of Road, Drainage, Sewer and Water Easements
(as defined in the South Westchester Executive Park Maintenance Association
Declaration).

         This Section shall not be merged in the execution and delivery of the
Assignment and shall instead survive the Closing Date and the delivery of the
Assignment.


7.       EVALUATION PERIOD

         7.1       For a period ending at 5:00 p.m. Eastern Time sixty (60) days
after the Effective Date (the "EVALUATION PERIOD"), Mack-Cali and its authorized
agents and representatives (for purposes of this Section 7, the "LICENSEE
PARTIES") shall have the right to enter upon the Property at all reasonable
times during normal business hours to perform an inspection of the Property.
Mack-Cali will provide to RMC notice of the intention of Mack-Cali or the other
Licensee Parties to enter the Property at least 24 hours prior to such intended
entry and specify the intended purpose therefor and the inspections and
examinations contemplated to be made and with whom any Licensee Party will
communicate. At RMC's option, RMC may be present for any such entry and
inspection. Notwithstanding anything to the contrary contained herein, no
physical testing or sampling shall be conducted during any such entry by
Mack-Cali or any Licensee Party upon the Property without RMC's specific prior
written consent.

         7.2       During the Evaluation Period, Mack-Cali and the Licensee
Parties shall have the right to review and inspect, at Mack-Cali's sole cost and
expense, all of the following which, to RMC's knowledge, are in RMC's possession
or control (collectively, the "DOCUMENTS"): all existing environmental reports
and studies of the Property that have been prepared for RMC (which Mack-Cali
shall have the right to have updated at Mack-Cali's sole cost and expense), real
estate tax bills, together with assessments (special or otherwise), ad valorem
and personal

                                       13
<Page>

property tax bills, covering the period of RMC's ownership of the Property, and
Permits and Licenses.

         7.3       In the event that Mack-Cali determines, after its inspection
of the Documents and Property, that it does not want to proceed with the
transaction as set forth in this Agreement, Mack-Cali shall have the right to
terminate this Agreement by providing written notice to RMC prior to the
expiration of the Evaluation Period. In the event Mack-Cali terminates this
Agreement in accordance with this Section 7.3, or under any other right of
termination as set forth herein, this Agreement shall be null and void and the
parties shall have no further obligation to each other. In the event this
Agreement is terminated, Mack-Cali shall return to RMC all copies Mack-Cali has
made of the Documents and all copies of any studies, reports or test results
regarding any part of the Property obtained by Mack-Cali, before or after the
execution of this Agreement, in connection with Mack-Cali's inspection of the
Property promptly following the time this Agreement is terminated for any
reason.

8.       CLOSING

         8.1       The consummation of the transaction contemplated hereunder
(the "CLOSING") shall take place at the offices of Mack-Cali Realty Corporation
located at 100 Clearbrook Road, Elmsford, New York, (i) five (5) business days
after the expiration of the Evaluation Period or (ii) earlier upon five (5)
business days following notice by Mack-Cali to RMC at any time before the
expiration of the Evaluation Period (the "CLOSING DATE").

         8.2       On the Closing Date, RMC shall, at its sole cost and expense,
deliver or cause to be delivered to Mack-Cali the following:

                   (a) a bargain and sale deed with covenants against grantor's
acts in the standard form (the "DEED"), duly executed and acknowledged by RMC;

                   (b) an affidavit, and such other document or instruments
required by the Title Company, executed by RMC certifying (i) against any work
done or supplies delivered to the Property which might be grounds for a
materialman's or mechanic's lien under or pursuant to the laws of the State of
New York, in form sufficient to enable the Title Company to affirmatively insure
Mack-Cali against any such lien, and (ii) that the signature(s) on the Deed
is/are sufficient to bind RMC and convey the Property to Mack-Cali;

                   (c) affidavits and other instruments (including but not
limited to all organizational documents of RMC, including operating agreements,
filed copies of limited liability certificates, articles of organization, and
good standing certificates) reasonably requested by Mack-Cali and the Title
Company evidencing the power and authority of RMC to enter into this Agreement
and any documents to be delivered hereunder, and the enforceability of the same;

                   (d) a certificate indicating that the representations and
warranties of RMC

                                       14
<Page>

made in this Agreement are true and correct in all material respects as of the
Closing Date, or if there have been any changes, a description thereof;

                   (e) all proper instruments as shall be reasonably required
for the assignment to Mack-Cali of all right, title and interest (if any) of RMC
in and to any award or payment made, or to be made, on account of (i) any damage
to the Property or any part thereof by reason of change of grade or closing of
any such street, road, highway or avenue, or (ii) any taking in condemnation or
eminent domain of any part of the Property;

                   (f) a certificate signed by a member or manager of RMC to the
effect that RMC is not a "foreign person" as such term is defined in Section
1445(f)(3) of the Internal Revenue Code of 1986, as amended (the "CODE"), in
order to avoid the imposition of the withholding tax payment pursuant to Section
1445 of the Code;

                   (g) all such transfer and other tax declarations and returns
and information returns, duly executed and sworn to by RMC, as may be required
of RMC by law in connection with the sale of the Property to Mack-Cali,
including but not limited to Internal Revenue Service forms; and

                   (h) A counterpart original of an assignment and assumption
of Seller's interest in the Service Contracts and the Licenses and Permits in
the form attached hereto as EXHIBIT B (the "ASSIGNMENT"), duly executed by
Seller, conveying and assigning to Purchaser all of Seller's right, title, and
interest, if any, in the Service Contracts and the Licenses and Permits;

                   (i) such other documents as may be reasonably required or
appropriate to effectuate the consummation of the transaction contemplated by
this Agreement.

         8.3       On the Closing Date, Mack-Cali shall, at its sole cost and
expense, deliver or cause to be delivered to RMC the following:

                   (a) the Consideration set forth in Section 2.1 of this
Agreement;

                   (b) a certificate indicating that the representations and
warranties of Mack-Cali made in this Agreement are true and correct as of the
Closing Date, or if there have been any changes, a description thereof; and

                   (c) such other documents as may be reasonably required or
appropriate to effectuate the consummation of the transaction contemplated by
this Agreement.

         8.4       RMC shall pay all state or county documentary stamps or
transfer taxes and recording fees and charges necessary or required in order for
the Deed to be recorded in the appropriate county register's or recorder's
office. Mack-Cali shall pay all title insurance premiums and examination fees
and the costs (if any) of its due diligence investigations, except as may
specifically be provided for herein. Each party shall be responsible for its own
attorney's

                                       15
<Page>

fees and one-half (1/2) of any reasonable escrow fees. The provisions of this
Section 8.4 shall survive the Closing.

9.       ADJUSTMENTS

         9.1       The real estate taxes due and payable with respect to the
Property for the fiscal/calendar year in which the Closing occurs shall be
apportioned as of midnight on the date preceding the Closing. If the Closing
Date shall occur before the tax rate is fixed, the apportionment of real estate
taxes shall be upon the basis of the tax rate for the preceding year applied to
the latest assessed valuation, and if subsequent to the Closing Date, the real
estate taxes (by reason of change in either assessment or rate or for any other
reason) for the Property shall be determined to be higher or lower than those
that are apportioned, a new computation shall be made, and RMC agrees to pay
Mack-Cali any increase shown by such recomputation and VICE VERSA.

         9.2       Except as otherwise provided in this Agreement, the
adjustments shall be made in accordance with the customs in respect to title
closings in the State of New York. Any errors in calculations or adjustments
shall be corrected or adjusted as soon as practicable after the Closing.

         9.3       The provisions of this Section 9 shall survive the Closing
Date.


10.      CONDITIONS PRECEDENT TO CLOSING

         10.1      The obligations of RMC under this Agreement to convey the
Property and to perform the other covenants and obligations to be performed by
RMC on or before the Closing Date shall be subject to the following conditions
(all or any of which may be waived, in whole or in part, by RMC):

                   (a) The representations and warranties made by Mack-Cali
herein shall be true and correct in all material respects with the same force
and effect as though such representations and warranties had been made on and as
of the Closing Date;

                   (b) RMC shall have performed all covenants and obligations
undertaken by RMC herein in all respects and complied with all conditions
required by this Agreement to be performed or complied with by it on or before
the Closing Date; and

                   (c) Mack-Cali shall have delivered to RMC all of the
documents provided herein for said delivery.

         10.2      The obligations of Mack-Cali to purchase the Property and to
perform the other covenants and obligations to be performed by Mack-Cali on or
before the Closing Date shall be

                                       16
<Page>

subject to the following conditions (all or any of which may be waived, in whole
or in part, by Mack-Cali):

                   (a) The survey of the Property shall include a certification
to Mack-Cali and its successors and assigns;

                   (b) The representations and warranties made by RMC herein
shall be true and correct in all material respects with the same force and
effect as though such representations and warranties had been made on and as of
the Closing Date;

                   (c) RMC shall have performed all covenants and obligations
undertaken by RMC herein in all respects and complied with all conditions
required by this Agreement to be performed or complied with by it on or before
the Closing Date;

                   (d) The Title Company is unconditionally prepared to issue a
Title Policy meeting the requirements for an "insurable title" as set forth in
Section 3.3 hereof;

                   (e) The Property shall be in compliance with all
Environmental Laws;

                   (f) RMC shall have delivered to Mack-Cali all of the
documents provided herein for said delivery.


11.      ASSIGNMENT OF THIS AGREEMENT

         Mack-Cali may not assign its rights under this Agreement except (i) to
a subsidiary or subsidiaries which are wholly-owned, directly or indirectly, by
Mack-Cali, or (ii) to a partnership in which any such wholly-owned subsidiary or
subsidiaries owns, either directly or indirectly, at least seventy-five (75%)
percent of the profits, losses and cash flow thereof, and controls the
management of the affairs of such partnership (any such entity, a "PERMITTED
ASSIGNEE"). In the event of an assignment by Mack-Cali to a Permitted Assignee,
Mack-Cali shall have the right at Closing to direct RMC to convey the Deed and
such other closing instruments to such Permitted Assignee. Notwithstanding the
foregoing, Mack-Cali shall not be relieved of its obligations under this
Agreement. Any other assignment or attempted assignment shall constitute a
default hereunder and shall be deemed null and void and of no force and effect.

12.      BROKER

         Mack-Cali and RMC represent that they have not dealt with any brokers,
finders or salesmen in connection with this transaction, and agree to indemnify,
defend and hold the other party harmless from and against any and all loss,
cost, damage, liability or expense (including reasonable attorneys' fees) which
either party may sustain, incur or be exposed to by reason of

                                       17
<Page>

any claim for fees or commissions made through the other party. The provisions
of this Section shall survive the Closing or other termination of this
Agreement.

13.      CONDEMNATION

         13.1      In the event that, prior to the Closing, RMC shall become
aware of the institution or threatened institution of any proceeding (judicial,
administrative or otherwise), by eminent domain or otherwise, which proposes to
affect a material portion of the Property, RMC shall give notice (the
"CONDEMNATION NOTICE") to Mack-Cali promptly thereafter. Within fifteen (15)
days following receipt of the Condemnation Notice, Mack-Cali shall have the
right and option to terminate this Agreement by giving RMC written notice
thereof.

         13.2      Any damage to or destruction of the Property as a result of a
taking by eminent domain shall be deemed "material" for purposes of this Section
if the estimate of the damage, which estimate shall be performed by an insurance
adjuster and Mack-Cali's architect, shall exceed three (3%) percent of the
Consideration. In the event that Mack-Cali shall elect to terminate this
Agreement in accordance with this Section, neither party shall have any further
liability or obligations to the other. In the event that Mack-Cali shall not
elect to terminate this Agreement, RMC shall promptly assign all proceeds of
such taking to Mack-Cali, the same shall be Mack-Cali's sole property, and
Mack-Cali shall have the sole right to settle any claim in connection with the
Property.

14.      PUBLICATION; CONFIDENTIALITY

         14.1      Mack-Cali shall have the right to make such public
announcements or filings with respect to the transaction contemplated by this
Agreement as Mack-Cali may deem reasonably prudent; PROVIDED, HOWEVER, that
Mack-Cali shall not issue any such announcement without the prior approval of
RMC as to the text of the announcement, which approval shall not be unreasonably
withheld or delayed. Notwithstanding the foregoing, Mack-Cali shall, without the
prior approval of RMC, be entitled to make such filings or announcements as may
be necessary upon the advice of counsel or as required by law.

         14.2      Without the prior written consent of the other party, until
Mack-Cali shall make a public announcement as provided in Section 13.1, neither
Mack-Cali nor RMC shall disclose, and RMC and Mack-Cali will direct their
respective representatives, employees, agents and consultants not to disclose,
to any person or entity the fact that Mack-Cali and RMC have entered into an
agreement to convey the Property or any of the terms, conditions or other facts
with respect to this Agreement. Notwithstanding the foregoing, either party may
disclose those terms and conditions which are required to be disclosed pursuant
to law or in order to comply with this Agreement; PROVIDED, HOWEVER, that the
disclosing party (i) shall use its best efforts to limit the disclosure to the
information necessary, (ii) shall advise any party to whom disclosure is made
that said terms and conditions are subject to a confidentiality requirement, and
(iii) shall obtain

                                       18
<Page>

the agreement of said party to keep any information disclosed to it as
confidential. In the event of a breach of the provisions of this Section 14, the
non-breaching party shall be entitled to all of its rights and remedies under
this Agreement, at law and/or in equity.

15.      REMEDIES

         15.1      In the event that Mack-Cali fails to perform on the Closing
Date, this Agreement shall terminate and neither party shall have any further
rights or obligations hereunder, except that RMC shall be entitled to such
remedies which it may have against Mack-Cali under this Agreement, at law, or in
equity by reason of Mack-Cali's default.

         15.2      (a) If, after complying with the terms of this Agreement, RMC
shall be unable to convey the Property in accordance with the terms of this
Agreement, then the sole obligation and liability of RMC shall be to perform in
accordance with Section 3.7, following which this Agreement shall be deemed
canceled and the parties hereto shall be released of all obligations and
liabilities under this Agreement, except for those provisions which are
expressly stated to survive the cancellation or termination of this Agreement.

                   (b) In the event of any default on the part of RMC or RMC's
failure to comply with any representation, warranty or agreement by RMC in any
material respect, Mack-Cali shall be entitled (i) to terminate this Agreement
upon notice to RMC, in which event neither party shall thereafter have any
further obligations under this Agreement, except as otherwise provided herein;
(ii) to commence an action against RMC seeking specific performance of RMC's
obligations under this Agreement; (iii) to pursue all of its remedies under this
Agreement, at law or in equity; or (iv) to do any or all of the above.

         15.3      The acceptance of the Deed by Mack-Cali shall be deemed a
full performance and discharge of every agreement and obligation of RMC required
to be performed under this Agreement, except those provisions which are
expressly stated in this Agreement to survive the Closing or which, by their
terms, cannot be performed or complied with until after the Closing.

         15.4      The provisions of this Section 15 shall survive the Closing
or earlier termination of this Agreement.


16.      NOTICES

         16.1      All notices, demands, requests, or other writings
(individually, a "NOTICE" and collectively, "NOTICES") required to be given or
made or sent under this Agreement, or which may be given or made or sent, by
either party hereto to the other, shall be in writing and shall be delivered by
using any nationally-recognized overnight delivery service with all transmittal
fees prepaid, properly addressed, and sent to the following:

                                       19
<Page>

         IF TO MACK-CALI:           Mack-Cali Realty Acquisition Corp.
                                    11 Commerce Drive
                                    Cranford, New Jersey 07016
                                    Attn:  Roger W. Thomas, General Counsel
                                    Tel:   (908) 272-8000
                                    Fax:   (908) 497-0475

         with a separate notice to: Attn:  Mitchell E. Hersh, CEO
                                    Tel:   (908) 272-8000
                                    Fax:   (908) 272-6755


         IF TO RMC:
                                    Robert Martin Company, LLC
                                    100 Clearbrook Road
                                    Elmsford, New York 10523
                                    Attn:  Martin S. Berger
                                    Tel:   (914) 592-4800
                                    Fax:   (914) 592-4836

                  with a copy to:   Robert Martin Company, LLC
                                    100 Clearbrook Road
                                    Elmsford, New York  10523
                                    Attn:  Lloyd I. Roos, Esq.
                                    Tel:   (914) 593-7918
                                    Fax:   (914) 592-5486

or to such other address as either party may from time to time designate by
written notice to the other. Notices given by overnight delivery service as
aforesaid shall be deemed given and effective when received or when delivery is
refused, and the records of the delivery service shall be conclusive with
respect to the date of receipt or refusal of delivery. Notices may be given by
counsel for the parties described above, and such Notices shall be deemed given
by said party for all purposes hereunder.

         16.2      Any Notice which, pursuant to this Agreement, requires a
response within a certain number of days or gives the other party certain rights
if said party responds within a certain number of days shall set forth such
requirement or right in order for the Notice to be effective.

17.      MISCELLANEOUS

         17.1      If any instrument or deposit is necessary in order to obviate
a defect in or objection or exception to title, the following shall apply: (a)
any such instrument shall be in such form and shall contain such terms and
conditions as may be required by the Title Company to omit any defect, objection
or exception to title, (b) any such deposit shall be made with the Title

                                       20
<Page>

Company, and (c) RMC agrees to execute, acknowledge and deliver any such
instrument and to make any such deposit.

         17.2      This Agreement (a) constitutes the entire agreement between
the parties and incorporates and supersedes all prior negotiations and
discussions between the parties, (b) cannot be amended, waived or terminated
orally, but only by an agreement in writing signed by the party to be charged,
(c) shall be interpreted and governed by the laws of the State of New York, and
(d) shall be binding upon the parties hereto and their respective successors and
assigns.

         17.3      The caption headings in this Agreement are for convenience
only, are not intended to be part of this Agreement, and shall not be construed
to modify, explain or alter any of the terms, covenants or conditions herein
contained. If any term, covenant or condition of this Agreement is held to be
invalid, illegal or unenforceable in any respect, this Agreement shall be
construed without such provision.

         17.4      From time to time, each party shall execute, acknowledge and
deliver such further instruments, and perform such additional acts, as the other
party may reasonably request in order to effectuate the intent of this
Agreement, and the foregoing requirement shall survive the Closing. Nothing
contained in this Agreement shall be deemed to create any rights or obligations
of partnership, joint venture or similar association between RMC and Mack-Cali.
This Agreement shall be given a fair and reasonable construction in accordance
with the intentions of the parties hereto, and without regard to or aid of
canons requiring construction against RMC, Mack-Cali or the party whose counsel
drafted this Agreement.

         17.5      This Agreement shall not be effective or binding until such
time as it has been executed and delivered by all parties hereto. This Agreement
may be executed in one or more counterparts, each of which when so executed and
delivered shall be deemed an original, but all of which when taken together
shall constitute but one and the same instrument.

         17.6      All references herein to any section, Schedule or Exhibit
shall be to the sections of this Agreement and to the schedules and exhibits
annexed hereto unless the context clearly dictates otherwise. All of the
Schedules and Exhibits annexed hereto are, by this reference, incorporated
herein.

         17.7      In the event of any litigation or alternative dispute
resolution between RMC and Mack-Cali in connection with this Agreement or the
transaction contemplated herein, the non-prevailing party in such litigation or
alternative dispute resolution shall be responsible for the payment of all
expenses and reasonable attorneys' fees incurred by the prevailing party.

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                                       21
<Page>

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date first above written.

                                    ROBERT MARTIN COMPANY,  LLC
                                    A NEW YORK LIMITED LIABILITY COMPANY

                                            By:   /s/ Martin  Berger
                                                ------------------------------
                                                  Name: Martin Berger
                                                  Title: Manager

                                    MACK-CALI REALTY ACQUISITION CORP.
                                    A DELAWARE CORPORATION


                                    By:    /s/ Roger W. Thomas
                                        ----------------------------------
                                           Name:  Roger W. Thomas
                                           Title: Executive Vice President

                                       22