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- -------- U.S. SECURITIES AND EXCHANGE COMMISSION
FORM 4 Washington, D.C. 20549
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/ / CHECK THIS BOX IF NO STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP
LONGER SUBJECT TO
SECTION 16. FORM 4 OR Filed pursuant to Section 16(a) of the Securities and Exchange Act of 1934,
FORM 5 OBLIGATIONS MAY Section 17(a) of the Public Utility Holding Company Act of 1935 or
CONTINUE. Section 30(f) of the Investment Company Act of 1940
SEE INSTRUCTION 1(b).
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1. Name and Address of Reporting Person* 2. Issuer Name and Ticker or Trading Symbol 6. Relationship of Reporting Person(s)
to Issuer (Check all applicable)
__X_ Director ____ 10% Owner
Byrne Brendan T. Mack-Cali Realty Corporation (CLI)
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(Last) (First) (Middle) 3. IRS or Social Security 4. Statement for title (specify
Number of Reporting Month/Year below) below
Person (Voluntary) ----------------- ------------------
c/o Mack-Cali Realty Corporation
11 Commerce Drive 12/99
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(Street) 5. If Amendment, (Check Applicable Line)
Date of Original _X_Form filed by One Reporting Person
Cranford, New Jersey 07016 (Month/Year) ___Form filed by More than One
- -------------------------------------------- Reporting Person
(City) (State) (Zip)
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TABLE I - NON-DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
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1. Title of Security 2. Trans- 3. Trans- 4. Securities Acquired (A) 5. Amount of 6. Owner- 7. Nature
(Instr. 3) action action or Disposed of (D) Securities ship of In-
Date Code (Instr. 3, 4 and 5) Beneficially Form: direct
(Month/ (Instr. 8) Owned at Direct Bene-
Day/ End of (D) or ficial
Year) ------------------------------------------- Month Indirect Owner-
Code V Amount (A) or (Instr. 3 (I) ship
(D) Price and 4) (Instr. 4) (Instr. 4)
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Common Stock 12/13/99 P 500 A $24.187 600 I By wife
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* If the form is filed by more than one reporting person, SEE Instruction 4(b)(v).
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. (Over)
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FORM 4 (CONTINUED) TABLE II - DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
(E.G., PUTS, CALLS, WARRANTS, OPTIONS, CONVERTIBLE SECURITIES)
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1. Title of Derivative Security 2. Conver- 3. Trans- 4. Transac- 5. Number of Deriv- 6. Date Exer-
(Instr. 3) sion or action tion Code ative Securities Ac- cisable and Ex-
Exercise Date (Instr. 8) quired (A) or Dis- piration Date
Price of (Month/ posed of (D) (Month/Day/
Deriv- Day/ (Instr. 3, 4, and 5) Year)
ative Year)
Security
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Code V (A) (D) Date Expira-
Exer- tion
cisable Date
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7. Title and Amount of Under- 8. Price 9. Number 10. Owner- 11. Nature
lying Securities of of Deriv- ship of In-
(Instr. 3 and 4) Deriv- ative Form direct
ative Securi- of De- Bene-
Secur- ties rivative ficial
ity Bene- Secu- Own-
(Instr. ficially rity: ership
5) Owned Direct (Instr. 4)
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Title Amount or of Indi-
Number of Month rect (I)
Shares (Instr. 4) (Instr. 4)
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Explanation of Responses:
/s/ Brendan T. Byrne 1/10/00
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**Intentional misstatements or omissions of facts constitute **Signature of Reporting Person Date
Federal Criminal Violations. SEE 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed.
If space is insufficient, SEE Instruction 6 for procedure.
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