FORM 5
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
Form 3 Holdings Reported
Form 4 Transactions Reported
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

ANNUAL STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940
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1. Name and Address of Reporting Person *
MACK WILLIAM L
2. Issuer Name and Ticker or Trading Symbol
MACK CALI REALTY CORP [CLI]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)

C/O MACK-CALI REALTY CORPORATION, 343 THORNALL STREET
3. Statement for Issuer's Fiscal Year Ended (Month/Day/Year)
12/31/2010
(Street)


EDISON, NJ 08837
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Reporting
(check applicable line)

_X_ Form Filed by One Reporting Person
___ Form Filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned at end of Issuer's Fiscal Year
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Amount (A) or (D) Price

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number. SEC 2270 (9-02)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned at End of Issuer's Fiscal Year
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
(A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Units of Limited Partnership Interest $ 0 (1) 04/30/2010   G(2)   978,835 08/08/1988(3) 08/08/1988(3) Common Stock
978,835
$ 0 0 (4)
I
By Grantor Retained Annuity Trust

Reporting Owners

Reporting Owner Name / Address Relationships
Director 10% Owner Officer Other
MACK WILLIAM L
C/O MACK-CALI REALTY CORPORATION
343 THORNALL STREET
EDISON, NJ 08837
  X      

Signatures

/s/ William L. Mack 02/11/2011
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) Common units of limited partnership interest of Mack-Cali Realty, L.P. ("Common Units") are redeemable by the holders of Common Units, subject to certain restrictions, on the basis of one Common Unit for either one share of the Corporation's common stock ("Common Stock"), or cash equal to the fair market value of a share of Common Stock at the time of the redemption. The Corporation has the option to deliver shares of Common Stock in exchange for all or any portion of the cash requested.
(2) Pursuant to the operative terms of the grantor retained annuity trust (the "GRAT"), the reporting person's term as trustee of the GRAT expired on April 30, 2010. Accordingly, the reporting person ceased to exercise control over the holdings of the GRAT and no longer has an indirect beneficial ownership interest in the issuer's securities held by the GRAT.
(3) The right to convert Common Units is not subject to expiration.
(4) Reported amount excludes the following securities indirectly beneficially owned by the reporting person as of February 11, 2011: (i) 100,000 Common Units held by the William & Phyllis Mack Family Foundation, Inc. a charitable foundation of which the reporting person is a trustee (the "Foundation"); and (ii) 833,770 Common Units held by other trusts (the "Trusts"). Pursuant to Rule 13d-4, the reporting person disclaims beneficial ownership of all securities held by the Foundation and the Trusts. Reported amount also excludes the following securities directly beneficially owned by the reporting person as of February 11, 2011: (i) 14,215.202 phantom stock units; (ii) 1,368,279 Common Units; and (iii) options to purchase 10,000 shares of Common Stock.

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