SCHEDULE 13G/A

(Rule 13d-102)

INFORMATION TO BE INCLUDED IN STATEMENTS FILED PURSUANT

TO RULES 13d-1(b), (c) and (d) AND AMENDMENTS THERETO FILED

PURSUANT TO RULE 13d-2(b)

(Amendment No. 22)*

MACK-CALI REALTY CORPORATION

(Name of Issuer)

COMMON STOCK

(Title of Class of Securities)

554489 10 4

(CUSIP Number)

December 31, 2020

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

*The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

* See Response to Item 4.

SIGNATURES

After reasonable inquiry and to the best of our knowledge and belief, we certify that the information set forth in this statement is true, complete and correct.

Exhibit A

THE MACK GROUP

(1)  Includes shares of Common Stock, restricted shares of Common Stock (vested and unvested), and limited partnership units redeemable for shares of Common Stock.

(2)  William L. Mack, a member of the Mack Group, is a trustee of the William and Phyllis Mack Foundation, Inc., a charitable foundation that owns 100,000 reported shares. Earle I. Mack, a member of the Mack Group, is a trustee of the Earle I. Mack Foundation, Inc., a charitable foundation that owns 30,000 reported shares.  Richard Mack and Stephen Mack, members of the Mack Group, are trustees of The Mack 2010 Family Trust II, a trust that owns 330,097 reported shares.  David S. Mack, a member of the Mack Group, is a trustee of The David and Sondra Mack Foundation, a charitable foundation that owns 225,000 reported shares.  Stephen Mack, a member of the Mack Group, is a trustee of The Stephen Mack and Kelly Mack Family Foundation, a charitable foundation that owns 5,000 reported shares.  William L. Mack, Earle I. Mack, Richard Mack, David S. Mack and Stephen Mack, pursuant to Rule 13d-4 of the Securities Exchange Act of 1934, as amended, each hereby specifically disclaims beneficial ownership of any shares owned by such respective trust or foundations reported on this Schedule.

Exhibit B

JOINT FILING AGREEMENT

In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended, the persons named below agree to the joint filing on behalf of each of them of a statement on Schedule 13G (including amendments thereto) with respect to the common stock, par value $0.01 per share, of Mack-Cali Realty Corporation.