FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * Mcbratney Patricia Marie   2. Issuer Name and Ticker or Trading Symbol CyrusOne Inc. [CONE] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Vice President and Controller (Last) (First) (Middle) C/O CYRUSONE INC., 1649 WEST FRANKFORD ROAD 3. Date of Earliest Transaction (Month/Day/Year) 03/31/2015 (Street) CARROLLTON, TX 75007 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price Common Stock 03/31/2015   F   66 (1) D $ 31.12 22,689 D

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Stock Option

$ 23.58

03/31/2015

A

153

(2)

04/17/2023

Common Stock

153

$ 0

327

D

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Mcbratney Patricia Marie C/O CYRUSONE INC. 1649 WEST FRANKFORD ROAD CARROLLTON, TX 75007			Vice President and Controller

Signatures

/s/ Thomas W. Bosse, Attorney-in-Fact		04/02/2015
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Surrender of shares of common stock to cover tax withholding obligations pursuant to scheduled vesting of restricted shares of common stock granted under the CyrusOne 2012 Long Term Incentive Plan.
(2)	On April 17, 2013, the reporting person was granted options which vest based on the achievement of the applicable performance criteria during the 2013-2015 performance period as follows: (i) up to 50% of the maximum number of such options will vest in cumulative installments on March 31, 2014, March 31, 2015 and March 31, 2016, based on the Company achieving certain cumulative EBITDA targets; and (ii) up to 50% of the maximum number of such options will vest on March 31, 2016 based on the Company achieving certain shareholder returns as measured against an index. Performance for 2013 and 2014 resulted in vesting of 174 options in 2014 and 153 options in 2015.

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