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                                                                   Exhibit 10.12

                          MACK-CALI REALTY CORPORATION

                        RESTRICTED SHARE AWARD AGREEMENT

                                 BARRY LEFKOWITZ

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                         AGREEMENT EVIDENCING THE GRANT
                      OF A RESTRICTED SHARE AWARD PURSUANT
                        TO THE EMPLOYEE STOCK OPTION PLAN
                         OF MACK-CALI REALTY CORPORATION

            AGREEMENT ("Agreement") effective as of July 1, 1999, ("Grant Date")
by and between Mack-Cali Realty Corporation (the "Company") and Barry Lefkowitz
("Recipient").

            WHEREAS, pursuant to the Employee Stock Option Plan of Mack-Cali
Realty Corporation which was originally effective August 31, 1994 and amended
and restated as of December 11, 1998 (the "Plan"), the Company hereby awards
shares of the Company's common stock, par value $.01 per share ("Common Stock")
to the Recipient subject to such terms, conditions, and restrictions
(hereinafter, "Restricted Share Award") as set forth in the Plan, this
Agreement, and the Second Amended and Restated Employment Agreement dated as of
July 1, 1999 by and between the Company and Recipient (the "Employment
Agreement"), and

            WHEREAS, Recipient has agreed under the amended terms of the
Employment Agreement to change his employment period to four (4) years, and to
amend the amount of the severance payment Recipient may be eligible to receive
upon termination of employment with the Company, and

            WHEREAS, upon the vesting of Restricted Shares, Recipient is also
entitled to receive a tax gross-up from the Company under the amended terms of
the Employment Agreement to enable Recipient to retain as many shares of Common
Stock as possible,

            NOW THEREFORE, the parties hereto hereby agree as follows:

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            1. Award of Shares of Restricted Stock.

            Pursuant to the Plan, the Committee hereby awards to the Recipient,
effective as of the Grant Date, a Restricted Share Award representing the
conditional receipt of 26,094 shares of Common Stock ("Restricted Shares") at no
out-of-pocket cost to the Recipient subject to the terms, conditions and
restrictions set forth herein. Except for defined terms set forth in Section 4
below, capitalized terms not otherwise defined in this Agreement shall be as
defined in the Plan.

            2. Award Restrictions.

                  (a) General Rules. Ownership of Restricted Shares shall not
vest in the Recipient, and shall be subject to forfeiture until the conditions
of Section 2(b) and (c) or Section 4 are fully satisfied. For purposes of this
Agreement, the following concepts shall be defined as follows: (i) the lapse of
restrictions on the Recipient's rights with respect to the Restricted Shares
granted hereunder shall be referred to as "Vesting"; (ii) the period between the
Grant Date and the date of Vesting shall be referred to as the "Vesting Period";
and (iii) the date Vesting occurs shall be referred to as the "Vesting Date."

                  (b) Vesting. An aggregate of 26,094 Restricted Shares may vest
in the Recipient and vest on either a year by year basis over a five year
Vesting Period or on a cumulative basis over a seven year maximum Vesting
Period. The number of Restricted Shares scheduled to be vested and earned on
each Vesting Date on a year by year basis provided the Performance Goals
specified in Section 2(c) below are satisfied is as follows:


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                    Restricted Shares             Vesting Date
                    -----------------             ------------

                          3,914                 January 1, 2000
                          3,914                 January 1, 2001
                          5,218                 January 1, 2002
                          6,523                 January 1, 2003
                          6,525                 January 1, 2004

                  The Vesting Date for this Agreement shall be each January 1st
through and including January 1, 2006. In determining the number of Restricted
Shares which are earned and vested, fractional shares shall be rounded down to
the nearest whole number and shall be aggregated and earned on the next Vesting
Date.

                  (c) Performance Goals. (i) The Restricted Shares shall vest on
the applicable Vesting Date on a year by year basis provided one of the
following financial tests ("Financial Tests") is met for the measurement period
ending on the last day of the Company's fiscal year immediately preceding such
Vesting Date: (A) the Company achieves an eight percent (8%) funds from
operations per common share ("FFO") increase, or (B) shareholders receive a
twelve and three quarters percent (12.75%) total return (dividends, assuming
reinvestment upon applicable payment date, plus stock appreciation per share of
Common Stock). For purposes of this Agreement, FFO shall mean (i) net income
(loss) before minority interest of unit holders, computed in accordance with
generally accepted accounting principles ("GAAP"), excluding the effect of
straight lining of rents, gains (or losses) from debt restructuring, other
extraordinary and significant non-recurring items, and gains (or losses) on sale
of property and other property-related valuation allowances, plus real estate
related depreciation and amortization, as calculated in accordance with the
National Association of Real Estate Investment Trusts definition published in
March 1995 after


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adjustment for straight lining of rents and as applied in accordance with the
accounting practices and policies of the Company in effect from time to time on
a consistent basis to the entire Vesting Period, divided by (ii) the sum of (A)
the diluted weighted average number of outstanding shares of Common Stock and
(B) the diluted weighted average number of outstanding common limited
partnership units of Mack-Cali Realty, L.P., a Delaware limited partnership of
which the Company is the sole general partner, for the applicable period with
such calculations being made all before the effect on FFO and diluted common
shares/common limited partnership units resulting from certain non-recurring
cash payments made pursuant to certain written employment agreements and from
the vesting of restricted share awards and other similar plans or compensation
arrangements for the applicable period.

                        (ii) In the event that neither of the Financial Tests
above is satisfied for the fiscal year of the Company corresponding to the
applicable Vesting Date ("Non-Achievement Year"), any Restricted Shares that
failed to vest under the annual performance goal criteria on such Date may vest
on such Date or on a subsequent Vesting Date provided the test described below
is satisfied (the "Cumulative Test"). The Cumulative Test shall be applied at
the end of the Non-Achievement Year or any subsequent fiscal year ("Catch-Up
Year") with respect to any Non-Achievement Year provided a Financial Test was
satisfied in a prior fiscal year or is satisfied in a Catch-Up Year, by applying
the aggregate Financial Test percentages and the performance goal requirement on
a cumulative basis beginning with the first fiscal year of the Vesting Period
and ending with the Non-Achievement Year or the Catch-Up Year, as applicable. In
the event the Cumulative Test is satisfied (i.e., the


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aggregate increase in FFO or aggregate total return is not less than the minimum
percentage required to satisfy the Financial Test after taking into account the
applicable Non-Achievement Year), the Restricted Shares that failed to vest in
the Non-Achievement Year shall automatically vest on the Vesting Date applicable
to the Non-Achievement Year or the Catch-Up Year, as the case may be. For
example, if vesting occurred in years one (1) and two (2), year three (3) is a
Non-Achievement Year, and the Cumulative Test is met for the Non-Achievement
Year (i.e., either FFO is not less than twenty-four (24%) percent or the
aggregate return is not less than thirty-eight and one-quarter (38.25%) percent)
vesting would occur on the Vesting Date applicable to the Non-Achievement Year.
In the event the Cumulative Test is not met in the Non-Achievement Year, one of
the Financial Tests is met in year four (4), the Cumulative Test may be used.
Under this scenario, vesting in that portion of the Restricted Stock Award
scheduled to vest in year three (3) will occur in year four (4) if either the
aggregate FFO is not less than thirty-two percent (32%) or the aggregate total
return is not less than fifty-one percent (51%) at the end of the fourth (4th)
fiscal year. Rules for Application of the Cumulative Test: (a) the Cumulative
Test will be applied first at the end of any Non-Achievement Year, (b) it is not
necessary for any Catch-Up Year to immediately succeed a Non-Achievement Year in
order for the Cumulative Test to be applicable as long as the Catch-Up Year
occurs during the Vesting Period, (c) if two (2) or more Non-Achievement Years
have occurred during the Vesting Period and remain non-vested, in the event that
the Cumulative Test is met on a partial basis so that at least one (1) full
year's vesting may occur, the Restricted Share Award granted with respect to the
last Non-Achievement Year that has occurred, shall vest first and any


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excess shall be credited to another Non-Achievement Year and (d) the Cumulative
Test may be met on a partial basis by aggregating percentages in excess of the
minimum annual requirement from more than one (1) fiscal year in the Vesting
Period. For example, if vesting occurred in year one (1) and the FFO is sixteen
(16%) percent, years two (2) and three (3) are Non-Achievement Years with a loss
in year two (2) of two (2%) percent and year three (3) the FFO is four (4%)
percent, the Restricted Shares awarded with respect to year three (3) would vest
under the Cumulative Test and two (2%) percent of the remaining FFO would be
available to be used in year two (2) or any other year (e.g., in the event that
FFO were fourteen (14%) percent in year four (4), the Restricted Shares
applicable to year two (2) would also vest. In the alternative, if FFO were six
(6%) percent in year four (4), year four (4) would vest and year two (2) would
remain a Non-Achievement Year). Notwithstanding any contrary provisions
contained in this Section 2(c) and subject to Section 4 below, any Restricted
Shares that have not been earned and vested by January 1, 2004 on a year by year
basis or by January 1, 2006 pursuant to the Cumulative Test shall automatically
be canceled and forfeited.

                  (d) Lapse of Restrictions. Upon the Vesting of Restricted
Shares, the Recipient shall own the Shares free and clear of all restrictions
imposed by this Agreement and the Recipient shall be free to hold or dispose of
such Shares in his discretion, subject to applicable federal and state law or
regulations.

                  (e) Prohibition Against Assignment. During the Vesting Period,
the Restricted Shares may not be transferred or encumbered by the Recipient by
means of sale, assignment, mortgage, transfer, exchange, pledge, or otherwise.
The


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levy of any execution, attachment, or similar process upon the Restricted Shares
shall be null and void.

            3. Stock Certificates.

                  (a) Certificates. Restricted Shares shall be evidenced by one
or more stock certificates registered in the name of the Recipient or a nominee
or nominees therefor. Prior to Vesting, the Company shall prepare and issue
separate certificates for the Restricted Shares scheduled to vest in each year
(the "Share Certificates"), which shall be registered in the name of the
Recipient and which shall bear such restrictive legend or legends (if any) as
the Company may deem necessary or desirable under any applicable law.

                  (b) Stock Powers. The Recipient shall execute and deliver to
the designee of the Company (the "Designee") stock powers corresponding to the
Share Certificates designating the Company as the transferee of an unspecified
number of Shares, which stock powers may be completed by the Designee as
specified herein. The Recipient and the Company each waive the requirement that
the signature of the Recipient on the stock powers be guaranteed. Upon receipt
of a copy of this Agreement and the stock powers, each signed by the Recipient,
the Designee shall promptly notify the proper officers of the Company and the
Share Certificates and stock powers shall be held by the Company in accordance
with the terms of this Agreement.

                  (c) Effect of Vesting. Upon Vesting, the Company shall cause
to be delivered to the Recipient (i) a certificate for the Shares which have
vested free and clear of restrictive legends and (ii) any stock powers signed
hereunder by the Recipient remaining in its possession related to the vested
shares. In the event that the


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Recipient dies before delivery of the certificate, such certificate shall be
delivered to, and registered in the name of, the Recipient's beneficiary or
estate, as the case may be.

                  (d) Rights of Stockholder. Except as otherwise provided in
Section 2 and this Section 3, during the Vesting Period and after the
certificates for the Restricted Shares have been issued, the Recipient shall be
entitled to all rights of a stockholder of the Company, including the right to
vote and the right to receive dividends, with respect to the Restricted Shares
subject to this Agreement. Subject to applicable withholding requirements, if
any, dividends on the Restricted Shares shall be paid to the Recipient when
earned and payable.

                  (e) Power of Designee. The Designee is hereby authorized by
the Recipient to utilize the stock power delivered by the Recipient to transfer
all forfeited Shares to the Company upon receipt of instructions from a duly
authorized representative of the Company.

            4. Termination of Employment; Change in Control.

                  (a) Termination Due to Disability, Death or for Good Reason;
Change in Control. Unless otherwise provided in the Employment Agreement and
notwithstanding any provision of the Plan to the contrary, if the Recipient
terminates employment with the Company due to Disability, death, for Good Reason
or a termination initiated by the Company without Cause, all Restricted Shares
subject to this Agreement and held by, or on behalf of, the Recipient shall be
deemed earned and vested as of the Recipient's last day of employment with the
Company. In addition, unless otherwise provided in the Employment Agreement and
notwithstanding any


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provision of the Plan to the contrary, all Restricted Shares subject to this
Agreement and held by the Recipient on the date a Change in Control occurs shall
be deemed earned and vested as of such date.

                  (b) Termination for Any Other Reason. Unless otherwise
provided in the Employment Agreement, if the Recipient's employment with the
Company terminates prior to January 1, 2006 for reasons other than Disability,
death, a termination initiated by the Company without Cause or for Good Reason
or as a result of a Change in Control, any Restricted Shares subject to this
Agreement that have not been earned and vested prior to the Recipient's
termination of employment shall be immediately forfeited on the last day of the
Recipient's employment with the Company.

            5. Withholding.

            In connection with the delivery of any stock certificates, or the
making of any payment in accordance with the provisions of this Agreement, the
Company shall withhold Shares or cash amounts (for fractional Shares) equal to
the taxes then required by applicable federal, state and local law to be so
withheld.

            6. Adjustments for Capital Changes.

            In the event of any change in the outstanding shares of Common Stock
of the Company by reason of any stock dividend or split, recapitalization,
merger, consolidation, spin-off, reorganization, combination or exchange of
shares, or other similar corporate change, or other increase or decrease in such
shares effected without receipt or payment of consideration by the Company, a
duly authorized representative of the Company shall adjust the number of
Restricted Shares granted pursuant to the


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Plan and this Agreement to prevent dilution or enlargement of the rights granted
to the Recipient.

            7. No Right to Continued Employment.

            Nothing in this Agreement shall confer on the Recipient any right to
continue as an employee of the Company or in any way affect the Company's or any
subsidiary's right to terminate the Recipient's employment at any time.

            8. Notice.

            Any notice to the Company hereunder shall be in writing addressed
            to:

            Mack-Cali Realty Corporation
            11 Commerce Drive
            Cranford, New Jersey  07016

            Attn: Mitchell E. Hersh
                  Chief Executive Officer

            Any notice to the Recipient hereunder shall be in writing addressed
            to:

            Mr. Barry Lefkowitz
            4 Borden Place
            Livingston, New Jersey  07039

            or such other address as the Recipient shall notify the Company
            in writing.

            9. Entire Agreement; Effect of Employment Agreement.

                  (a) Entire Agreement. This Agreement contains the entire
understanding of the parties and shall not be modified or amended except in
writing and duly signed by each of the parties hereto. No waiver by either party
of any default under this Agreement shall be deemed a waiver of any later
default thereof.

                  (b) Effect of Employment Agreement. In the event the
Employment Agreement with the Company contains additional rights, duties and/or
obligations with respect to the Recipient, such terms and conditions shall
govern the


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Recipient's Restricted Share Award as if such terms and conditions had been set
forth herein; and in the event of any conflict or inconsistency between the
terms of the Employment Agreement or this Agreement, the terms and conditions of
the Employment Agreement shall control.

            10. Construction.

            The various provisions of this Agreement are severable in their
entirety. Any determination of invalidity or unenforceability of any one
provision shall have no effect on the continuing force and effect of the
remaining provisions.

            11. Governing Law.

            This Agreement shall be governed by the laws of the State of New
Jersey applicable to contracts made, and to be enforced, within the State of New
Jersey.

            12. Successors.

            This Agreement shall be binding upon and inure to the benefits of
the successors, assigns and heirs of the respective parties.

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

                                          Mack-Cali Realty Corporation

                                          By:   /s/ Mitchell E. Hersh
                                                --------------------------------
                                                Mitchell E. Hersh
                                                Chief Executive Officer


                                          Recipient

                                          /s/ Barry Lefkowitz
                                          --------------------------------------
                                          Barry Lefkowitz


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