UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

FORM 8-K

CURRENT REPORT

PURSUANT TO SECTION 13 OR 15(d) OF THE

SECURITIES EXCHANGE ACT OF 1934

Date of report (Date of earliest event reported): December 23, 2013

MACK-CALI REALTY CORPORATION

(Exact Name of Registrant as Specified in Charter)

(732) 590-1000

(Registrant’s telephone number, including area code)

MACK-CALI REALTY, L.P.

(Exact Name of Registrant as Specified in Charter)

(732) 590-1000

(Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o        Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o        Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o       Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o       Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 7.01                                           Regulation FD.

On December 23, 2013, Mack-Cali Realty Corporation (the “General Partner”), the general partner of Mack-Cali Realty, L.P., issued a press release expressing comfort with net income and funds from operations (“FFO”) per diluted share for the full year 2014 as follows:

The above estimates reflect management’s view of current market conditions and certain assumptions with regard to rental rates, occupancy levels and other assumptions/projections.  Actual results could differ from these estimates.

It should be noted that FFO per diluted share as referenced in this Form 8-K is a non-generally accepted accounting principles (“GAAP”) measure of the General Partner’s performance in addition to its net income available to common shareholders per share.  FFO is defined as net income (loss) before noncontrolling interest of unitholders, computed in accordance with GAAP, excluding gains (or losses) from extraordinary items, sales of depreciable rental property, and impairments related to depreciable rental property, plus real estate-related depreciation and amortization. The General Partner believes that FFO per share is helpful to investors as one of several measures of the performance of an equity REIT. The General Partner further believes that as FFO per share excludes the effect of depreciation, gains (or losses) from sales of properties and impairments related to depreciable rental property (all of which are based on historical costs which may be of limited relevance in evaluating current performance), FFO per share can facilitate comparison of operating performance between equity REITs.

FFO per share should not be considered as an alternative to net income available to common shareholders per share as an indication of the General Partner’s performance or to cash flows as a measure of liquidity.  FFO per share presented herein and the press release filed herewith is not necessarily comparable to FFO per share presented by other real estate companies due to the fact that not all real estate companies use the same definition. However, the General Partner’s FFO per share is comparable to the FFO per share of real estate companies that use the current definition of the National Association of Real Estate Investment Trusts (“NAREIT”).

The General Partner’s press release announcing the net income and FFO guidance is furnished herewith as Exhibit 99.1 and incorporated herein by reference.

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Item 9.01              Financial Statements and Exhibits.

(d)  Exhibits

The information included in this Current Report on Form 8-K (including the exhibit hereto) is being furnished under Item 7.01, “Regulation FD Disclosure” and Item 9.01 “Financial Statements and Exhibits” of Form 8-K.  As such, the information (including the exhibit) herein shall not be deemed to be “filed” for the purposes of Section 18 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that Section, nor shall it be incorporated by reference into a filing under the Securities Act of 1933, as amended, or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing. This Current Report (including the exhibit hereto) will not be deemed an admission as to the materiality of any information required to be disclosed solely to satisfy the requirements of Regulation FD.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, each Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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EXHIBIT INDEX

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