UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549



FORM 10-K/A

(Amendment No. 1)



| | x | ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
SECURITIES EXCHANGE ACT OF 1934
| | - | ------------------------------------------------------------------------------------



For the fiscal year ended December 31,
2015

or





| |  ̈ | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d)
OF THE SECURITIES EXCHANGE ACT OF 1934
| | - | ----------------------------------------------------------------------------------------



For the transition period from . to .

Commission File No. 1-35933



GRAMERCY PROPERTY TRUST

(Exact name of registrant as specified in
its charter)





|Maryland                                                                                                           |  | 56-2466617                                                                 
|------------------------------------------------------------------------------------------------------------------ |  | ---------------------------------------------------------------------------
|(State or other jurisdiction
        incorporation or organization)                                                |  | (I.R.S. Employer of
        Identification No.)                            
|                                                                                                                   |  |                                                                            
|521 5th Avenue, 30th
        Floor, New York, NY 10175
        (Address of principal executive
offices – zip code) |  | (212) 297-1000
        (Registrant’s telephone number,
including area code)



Chambers Street Properties

47 Hulfish Street, Suite 210, Princeton,
New Jersey 08542

(Former name, former address and former
fiscal year, if changed since last report)



SECURITIES REGISTERED PURSUANT TO SECTION
12(b) OF THE ACT:





|Title of Each Class                                                                                             |  | Name of Each Exchange on Which Registered                       
|--------------------------------------------------------------------------------------------------------------- |  | ----------------------------------------------------------------
|Common Shares, $0.01 Par Value
        Series A Cumulative Redeemable
        Preferred Shares, $0.01 Par Value |  | New York Stock Exchange
        
        New York Stock Exchange



SECURITIES REGISTERED PURSUANT TO SECTION
12(g) OF THE ACT: None



Indicate by check mark
if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes x     
No  ̈



Indicate by check mark
if the registrant is not required to file reports pursuant to Section 13 or Section 15(d) of the Act. Yes  ̈
     No x



Indicate by check mark
whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2)
has been subject to such filing requirements for the past 90 days. Yes x      No
 ̈



Indicate by check mark
whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required
to be submitted and posted pursuant to Rule 405 of Regulation S-T (Section 232.405 of this chapter) during the preceding 12 months
(or for such shorter period that the registrant was required to submit and post such files). Yes x
     No  ̈



Indicate by check mark
if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to
the best of the registrant’s knowledge, in definitive proxy or information statements incorporated by reference in Part III
of this Form 10-K or any amendment to this Form 10-K.  ̈



Indicate by check mark
whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a small reporting company.
See the definitions of “large accelerated filer,” “accelerated filer” and “small reporting company”
in Rule 12b-2 of the Exchange Act.



|Large accelerated filer x | Accelerated filer  ̈ | Non-accelerated filer  ̈                       | Smaller reporting company  ̈
|------------------------- | ------------------- | --------------------------------------------- | ---------------------------
|                          |                     | (Do not check if a smaller reporting company)



Indicate by check mark
whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act). Yes  ̈     No
x



As
of February 25, 2016, the Registrant had 421,011,239 common shares outstanding. The aggregate market value of common shares held
by non-affiliates of the registrant (235,498,633 shares) at June 30, 2015, was $1,872,214,132. The aggregate market value
was calculated by using the closing price of the common shares as of that date on the New York Stock Exchange, which was $7.95
per share.













EXPLANATORY NOTE



We are filing this Amendment No. 1 on Form
10-K/A (the “Amendment”) to our Annual Report on Form 10-K for the fiscal year ended December 31, 2015, filed with
the Securities and Exchange Commission on February 29, 2016 (the “Original Filing”), for the sole purpose of filing
Exhibit 12.1 and 21.1, which were erroneously omitted from the Original Filing.



This amendment speaks as of the filing date
of the Original Filing, does not reflect events occurring after the original filing date or modify or update those disclosures
that may be affected by subsequent events, and no other changes are being made to any other disclosure contained in the Original
Filing or any exhibits thereto.





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PART IV



|ITEM 15. | EXHIBITS, FINANCIAL STATEMENT SCHEDULES
|-------- | ---------------------------------------



(a) The following documents are filed as
a part of this Report:





|12.1 | Computation of ratio of earnings to fixed charges and preferred shares dividend.                       
|---- | -------------------------------------------------------------------------------------------------------
|     |                                                                                                        
|21.1 | Subsidiaries of the Registrant.                                                                        
|     |                                                                                                        
|31.1 | Certification by the Chief Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.
|     |                                                                                                        
|31.2 | Certification by the Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.



3







SIGNATURES



Pursuant to the requirements
of Section 13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized, on March 2, 2016.



| | Gramercy Property Trust
| | -----------------------
| |                        
| |                        
| |                        
| | By:                    
| |                        
| |                        





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