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): November 1, 2017

CYRUSONE INC.

(Exact Name of Registrant as Specified in its Charter)

2101 Cedar Springs Road, Suite 900, Dallas, TX 75201

(Address of Principal Executive Office)

Registrant’s telephone number, including area code: (972) 350-0060

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))

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company o

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. o

ITEM 8.01 — OTHER EVENTS

On November 1, 2017, CyrusOne Inc., a Maryland corporation (the “Company”), announced that its operating partnership, CyrusOne LP, a Maryland limited partnership (the “Operating Partnership”), and CyrusOne Finance Corp., a Maryland corporation and a wholly owned subsidiary of the Operating Partnership (together with the Operating Partnership, the “Issuers”), priced their previously announced private offering of $200.0 million aggregate principal amount of their 5.000% senior notes due 2024 (the “New 2024 Notes”) and $200.0 million aggregate principal amount of their 5.375% senior notes due 2027 (the “New 2027 Notes” and, together with the 2024 New Notes, the “New Notes”) . The New 2024 Notes priced at 103.500% of the principal amount, plus accrued interest from September 15, 2017, and the New 2027 Notes priced at 105.375% of the principal amount, plus accrued interest from September 15, 2017. The New 2024 Notes will have terms substantially identical to those of the 5.000% senior notes due 2024 issued by the Issuers in March 2017, and the New 2027 Notes will have terms substantially identical to those of the 5.375% senior notes due 2027 issued by the Issuers in March 2017. The New 2024 Notes and the New 2027 Notes will be guaranteed by the Company, CyrusOne GP, a Maryland statutory trust, and certain of the Operating Partnership’s existing and future subsidiaries. The offering is expected to close, subject to certain customary closing conditions, on November 3, 2017.

The Issuers intend to use the net proceeds from the offering for the repayment of borrowings outstanding under the Operating Partnership’s revolving credit facility.

The New Notes and the related guarantees have been offered in the United States only to persons reasonably believed to be qualified institutional buyers in reliance on Rule 144A under the Securities Act of 1933, as amended (the “Securities Act”), and outside the United States only to non-U.S. investors pursuant to Regulation S under the Securities Act. The New Notes and the related guarantees will not be registered under the Securities Act or any state securities laws and may not be offered or sold in the United States absent an effective registration statement or an applicable exemption from registration requirements or a transaction not subject to the registration requirements of the Securities Act or any state securities laws.

This report does not constitute an offer to sell, or the solicitation of an offer to buy, any securities, nor shall there be any sale of securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction.

A copy of the press release announcing the foregoing is attached hereto as Exhibit 99.1.

ITEM 9.01 — FINANCIAL STATEMENTS AND EXHIBITS

(d) Exhibits

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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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