UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 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):

August 21, 2015 (August 18, 2015)

SL Green Realty Corp.

(EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

SL Green Operating Partnership, L.P.

(EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

Reckson Operating Partnership, L.P.

(EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

(212) 594-2700

(REGISTRANTS’ 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:

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 2.01.                                        Completion of Acquisition or Disposition of Assets.

On August 18, 2015, SL Green Realty Corp. (the “Company”) completed the acquisition of Eleven Madison Avenue (the “Property”) in New York City for $2.285 billion, plus approximately $300 million in costs associated with lease stipulated improvements to the Property.

The Property is a 29-story, 2.3 million square foot Class-A office property located in Midtown South.

The acquisition has been financed with a combination of existing corporate liquidity (including sale proceeds from certain assets) and a $1.4 billion 10-year, interest only, fixed rate mortgage, with an interest rate of 3.838% per annum, which is secured by the Property.

The Property was sold to the Company by a partnership of the Sapir Organization and CIM Group, with whom the Company has no other relationship.

Item 9.01. Financial Statements and Exhibits.

(a)                                 Financial statements of businesses acquired.

The financial information required by Item 9.01(a) of this Current Report on Form 8-K has not been included with this filing and will be filed by amendment to this Current Report on Form 8-K not later than seventy-one calendar days after the date that this Current Report on Form 8-K was required to be filed.

(b)                              Pro forma financial information.

The financial information required by Item 9.01(b) of this Current Report on Form 8-K has not been included with this filing and will be filed by amendment to this Current Report on Form 8-K not later than seventy-one calendar days after the date that this Current Report on Form 8-K was required to be filed.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrants have duly caused this report to be signed on their behalf by the undersigned hereunto duly authorized.

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