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: June 12, 2015

(Date of earliest event reported)

SUN COMMUNITIES, INC.

(Exact name of registrant as specified in its charter)

(248) 208-2500

(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:

On June 12, 2015, Sun Communities, Inc. (the “Company”) filed with the Securities and Exchange Commission (“SEC”) a shelf registration statement (File No. 333-204911) (the “Registration Statement”), which became immediately effective upon filing. On June 12, 2015, the Company also filed with the SEC a prospectus supplement, dated June 12, 2015, pursuant to Rule 424(b) under the Securities Act of 1933, as amended, relating to the resale by certain selling stockholders of shares of the Company’s common stock, par value $0.01 per share, from time to time (the “Prospectus Supplement”). In connection with filing the Prospectus Supplement, the Registration Rights Agreement, dated June 23, 2011 among the Company, beneficial holders of securities registered under the Prospectus Supplement and certain other parties was terminated.

SIGNATURES

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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