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): May 13, 2014

Gramercy Property Trust Inc.

(Exact Name of Registrant as Specified in its Charter)

(212) 297-1000

(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:

Item 8.01.              Other Events.

On May 13, 2014, Gramercy Property Trust Inc. (the “Company”) and its operating partnership, GPT Property Trust LP (the “Operating Partnership”), entered into an underwriting agreement (the “Underwriting Agreement”) with Morgan Stanley & Co. LLC, Merrill Lynch, Pierce, Fenner & Smith Incorporated and J.P. Morgan Securities LLC as representatives of the several underwriters named therein (collectively, the “Underwriters”), in connection with the underwritten public offering and sale of 40,000,000 shares of the Company’s common stock, par value $0.001 per share (the “Common Stock”), at a price to the public of $4.98 per share. Pursuant to the Underwriting Agreement, the Company granted the Underwriters a 30-day option to purchase up to an additional 6,000,000 shares of the Common Stock, which the Underwriters exercised in full on May 14, 2014. The closing of the offering is expected to occur on May 19, 2014, subject to the satisfaction of customary closing conditions.

The offering is being conducted pursuant to the Company’s effective shelf registration statement on Form S-3 (File No. 333-194976) under the Securities Act of 1933, as amended (the “Securities Act”), including the prospectus contained therein dated May 2, 2014 and a related prospectus supplement dated May 13, 2014, on file with the Securities and Exchange Commission.

The Underwriting Agreement contains customary representations, warranties and covenants by the Company and the Operating Partnership, as well as customary indemnification obligations of the Company and the Underwriters, including for liabilities under the Securities Act. The foregoing description of the Underwriting Agreement does not purport to be complete and is qualified in its entirety by reference to the full text of the Underwriting Agreement, which is filed as Exhibit 1.1 to this report and is incorporated herein by reference thereto.

A copy of the opinion of Venable LLP, Maryland counsel to the Company, with respect to the legality of the shares of Common Stock to be issued and sold in the offering is filed as Exhibit 5.1 hereto. A copy of the opinion of Morgan, Lewis & Bockius LLP with respect to tax matters is filed as Exhibit 8.1 hereto.

Item 9.01.              Financial Statements and Exhibits.

(d)          Exhibits.

The following exhibits are filed herewith:

Signature

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

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