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

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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(Print or Type Responses)
1. Name and Address of Reporting Person *
THOMAS ROGER W
   2. Issuer Name and Ticker or Trading Symbol
MACK CALI REALTY CORP [CLI] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
_____ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
EVP, Gen Counsel and Secretary
(Last)
(First)
(Middle)
C/O MACK-CALI REALTY CORPORATION, 11 COMMERCE DRIVE		 3. Date of Earliest Transaction (Month/Day/Year)
12/05/2003
(Street)

CRANFORD, NJ 07016		 4. If Amendment, Date Original Filed(Month/Day/Year)
 6. Individual or Joint/Group Filing(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 Following Reported Transaction(s)
(Instr. 3 and 4)		 6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)		 7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 12/05/2003   M(1)   9,000 A $38.75 87,885 D  
Common Stock 12/05/2003   S(1)   9,000 D $40.45 78,885 D  
Common Stock 12/08/2003   M(1)   5,000 A $38.75 83,885 D  
Common Stock 12/08/2003   S(1)   5,000 D $40.3 78,885 D  

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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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 Following Reported Transaction(s)
(Instr. 4)		 10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)		 11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (Right to Buy) $38.75 12/05/2003   M(1)   9,000   12/31/1997(2) 12/12/2007 Common Stock 9,000 $38.75 88,137 D  
Employee Stock Option (Right to Buy) $38.75 12/08/2003   M(1)   5,000   12/31/1997(2) 12/12/2007 Common Stock 5,000 $38.75 83,137 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
THOMAS ROGER W
C/O MACK-CALI REALTY CORPORATION
11 COMMERCE DRIVE
CRANFORD, NJ 07016		       EVP, Gen Counsel and Secretary  

Signatures

 /s/ Roger W. Thomas   12/09/2003
**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) The reporting person obtained and sold the Common Stock as a result of the cashless exercise of Employee Stock Options.
(2) On December 12, 1997, the reporting person was granted an option to purchase 97,137 shares of Common Stock. The options vested in five equal annual installments beginning December 31, 1997.

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