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Filed Pursuant to Rule 424(b)(2)
Registration Nos. 333-194771 and 333-194770

PROSPECTUS SUPPLEMENT
(To Prospectus Dated April 4, 2014 and Prospectus dated April 4, 2014)

LOGO

11,300,000 Shares

Common Stock



           We are offering 11,300,000 shares of our common stock, par value $0.01 per share.

           We intend to contribute the net proceeds from the sale of 6,918,597 shares of our common stock in this offering to our operating partnership, in exchange for 6,918,597 newly issued operating partnership units in accordance with the partnership agreement of our operating partnership. We intend to contribute the net proceeds from the sale of 81,403 shares of our common stock in this offering to CyrusOne GP, our wholly owned subsidiary. CyrusOne GP intends to subsequently contribute such proceeds to our operating partnership in exchange for 81,403 newly issued operating partnership units in accordance with the partnership agreement of our operating partnership. Our operating partnership intends to use the proceeds contributed by us and by CyrusOne GP, together with the net proceeds from the Credit Agreement Borrowings (as defined herein) and the Additional Debt Financing (as defined herein), to finance its pending acquisition (the "Cervalis Acquisition") of Cervalis Holdings LLC, a Delaware limited liability company ("Cervalis"), to pay fees and expenses related to the Cervalis Acquisition and for general corporate purposes. In the event we do not consummate the Cervalis Acquisition, we expect our operating partnership to use the net proceeds from this offering contributed by us and CyrusOne GP to repay outstanding indebtedness under our revolving credit facility and for general corporate purposes. The closing of this offering is not contingent on the completion of the Cervalis Acquisition, which, if completed, will occur subsequent to the closing of this offering.

           We intend to use the net proceeds from the sale of 4,300,000 shares of our common stock in this offering (or 5,995,000 shares if the underwriters exercise their option to purchase additional shares of our common stock in full) to acquire 4,300,000 (or 5,995,000, as applicable) operating partnership units from a subsidiary of Cincinnati Bell Inc.

           To assist us in complying with certain U.S. federal income tax requirements applicable to real estate investment trusts ("REITs"), among other purposes, our charter contains certain restrictions relating to the ownership and transfer of our stock, including an ownership limit of 9.8% of our outstanding common stock, subject to certain exceptions. See "Restrictions on Ownership and Transfer" and "Description of Securities—Restrictions on Ownership and Transfer" in the accompanying Universal Shelf Prospectus (as defined herein) and Common Stock Prospectus (as defined herein), respectively, for a detailed description of the ownership and transfer restrictions applicable to our common stock.

           Our common stock is listed on the NASDAQ Global Select Market under the symbol "CONE." On June 23, 2015, the last reported sale price of our common stock on the NASDAQ Global Select Market was $30.08 per share.

           Investing in our common stock involves risks. See "Risk Factors" beginning on page S-22 of this prospectus supplement.

 
  Per Share   Total  
Public Offering Price   $ 30.00   $ 339,000,000  
Underwriting Discounts(1)   $ 1.275   $ 14,407,500  
Proceeds to CyrusOne (before expenses)   $ 28.725   $ 324,592,500  

(1)
We refer you to "Underwriting" beginning on page S-32 of this prospectus supplement for additional information regarding underwriting compensation.

           We have granted the underwriters the option to purchase up to an additional 1,695,000 shares of our common stock at the public offering price, less underwriting discounts, for 30 days after the date of this prospectus supplement.

           Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus supplement or the accompanying prospectuses are truthful or complete. Any representation to the contrary is a criminal offense.

           We previously announced a dividend of $0.315 per share of common stock and common stock equivalent for the second quarter of 2015. The dividend will be paid on July 15, 2015, to stockholders of record at the close of business on June 26, 2015. This offering is expected to close prior to the close of business on June 26, 2015, and therefore purchasers of our common stock that take delivery of such stock on the closing date and continue to be stockholders of record as of the close of business on June 26, 2015 will receive the dividend.

           Delivery of the shares is expected to be made to investors through the book-entry delivery system of The Depository Trust Company on or about June 26, 2015.



Joint Book-Running Managers

Citigroup   Goldman, Sachs & Co.   Morgan Stanley

 

KeyBanc Capital Markets   Barclays   J.P. Morgan   Deutsche Bank Securities   RBC Capital Markets   TD Securities   Jefferies

Co-Managers

Stifel   SunTrust Robinson Humphrey   Raymond James

The date of this prospectus supplement is June 23, 2015.


        Neither we nor the underwriters have authorized anyone to provide any information or to make any representations other than those contained or incorporated by reference into this prospectus supplement, the accompanying prospectuses or any free writing prospectus we have prepared. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. We are offering to sell, and seeking offers to buy, shares of our common stock only in jurisdictions where offers and sales are permitted. You should assume that the information appearing in this prospectus supplement, the accompanying prospectuses, any free writing prospectus prepared by us and the documents incorporated by reference herein is accurate only as of their respective dates or on the date or dates that are specified in those documents regardless of the time of delivery of this prospectus supplement and the accompanying prospectuses or any sale of shares of our common stock. Our business, financial condition, liquidity, results of operations and prospects may have changed since those dates.


TABLE OF CONTENTS

Prospectus Supplement

 

About This Prospectus Supplement

   
S-iii
 

Special Note Regarding Forward-Looking Statements

    S-iv  

Where You Can Find More Information

    S-vi  

Incorporation By Reference

    S-vii  

Summary

    S-1  

Risk Factors

    S-22  

Use Of Proceeds

    S-28  

Capitalization

    S-29  

Price Range Of Common Stock And Dividends

    S-31  

Underwriting

    S-32  

Legal Matters

    S-38  

Experts

    S-39  

Prospectus dated April 4, 2014

 

Special Note Regarding Forward-Looking Statements

   
1
 

About this Prospectus

    3  

Where You Can Find More Information

    3  

Incorporation by Reference

    5  

Our Company

    6  

Risk Factors

    7  

Use of Proceeds

    7  

Ratio of Earnings to Consolidated and Combined Fixed Charges for CyrusOne Inc. and CyrusOne LP

    8  

Description of Debt Securities

    9  

Description of CyrusOne Inc. Common stock

    18  

Description of CyrusOne Inc. Preferred Stock

    20  

Description of Warrants

    23  

Description of Rights

    26  

Description of Units

    28  

Restrictions on Ownership and Transfer

    29  

Description of the Partnership Agreement of CyrusOne LP

    33  

Certain Provisions of Maryland Law and of Our Charter and Bylaws

    42  

U.S. Federal Income Tax Considerations

    49  

Plan of Distribution

    71  

S-i


Legal Matters

    74  

Experts

    74  

Prospectus dated April 4, 2014

 

Special Note Regarding Forward-Looking Statements

   
1
 

Where You Can Find More Information

    4  

Incorporation By Reference

    5  

Our Company

    6  

Risk Factors

    8  

Use Of Proceeds

    11  

Participating Holders

    12  

Plan Of Distribution

    14  

Description Of Securities

    16  

Description Of The Partnership Agreement Of Cyrusone LP

    22  

Certain Provisions Of Maryland Law And Of Our Charter And Bylaws

    31  

Exchange Of Operating Partnership Units For Common Stock

    38  

U.S. Federal Income Tax Considerations

    40  

Legal Matters

    61  

Experts

    61  

S-ii


Table of Contents

ABOUT THIS PROSPECTUS SUPPLEMENT

        This document contains three parts. The first part is this prospectus supplement, which describes the terms of this offering of common stock and also adds to and updates information contained in the accompanying prospectuses and the documents incorporated by reference. The second and third parts are the accompanying prospectuses, which provide more general information, some of which may not apply to this offering. It is important for you to read and consider all information contained in this prospectus supplement and the accompanying prospectuses in making your investment decision. You should also read and consider the additional information included in the documents incorporated by reference. See "Where You Can Find More Information" and "Incorporation by Reference" in this prospectus supplement. If the information in this prospectus supplement differs or varies from the information in the accompanying prospectuses or the documents incorporated by reference dated prior to the date of this prospectus supplement, you should rely on the information in this prospectus supplement.

        Except as otherwise indicated or required by the context, references in this prospectus supplement to (i) "CyrusOne," "we," "our," "us," "the Company" and "our company" refer to CyrusOne Inc., a Maryland corporation, together with its combined subsidiaries, including CyrusOne LP, a Maryland limited partnership (our "operating partnership" or "CyrusOne LP"), and CyrusOne GP, a Maryland statutory trust of which we are the sole beneficial owner and sole trustee and which is the sole general partner of our operating partnership ("CyrusOne GP") and (ii) "CBI" refers to Cincinnati Bell Inc., an Ohio corporation, and, unless the context otherwise requires, its consolidated subsidiaries.

        This prospectus supplement and (i) the accompanying prospectus dated April 4, 2014 are part of the Registration Statement (Registration No. 333-194771) that we filed with the Securities and Exchange Commission ("SEC") on April 4, 2014 (the "Universal Shelf Prospectus"), and (ii) the accompanying prospectus dated April 4, 2014 are part of the Registration Statement (Registration No. 333-194770) that we filed with the SEC on April 4, 2014 (the "Common Stock Prospectus"), each using a "shelf" registration process.

S-iii


Table of Contents

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

        This prospectus supplement, the accompanying prospectuses and the documents incorporated by reference herein contain forward-looking statements within the meaning of the federal securities laws. In particular, statements pertaining to our capital resources, portfolio performance and results of operations contain forward-looking statements. Likewise, our pro forma financial statements and all of our statements regarding anticipated growth in our funds from operations and anticipated market conditions, demographics and results of operations are forward-looking statements. You can identify forward-looking statements by the use of forward-looking terminology such as "believes," "expects," "may," "will," "should," "seeks," "approximately," "intends," "plans," "pro forma," "estimates" or "anticipates" or the negative of these words and phrases or similar words or phrases that are predictions of or indicate future events or trends and that do not relate solely to historical matters. You can also identify forward-looking statements by discussions of strategy, plans or intentions.

        Forward-looking statements involve numerous risks and uncertainties and you should not rely on them as predictions of future events. Forward-looking statements depend on assumptions, data or methods that may be incorrect or imprecise and we may not be able to realize them. The following factors, among others, could cause actual results and future events to differ materially from those set forth or contemplated in the forward-looking statements:

S-iv


Table of Contents

        While forward-looking statements reflect our good faith beliefs, they are not guarantees of future performance. We disclaim any obligation to publicly update or revise any forward-looking statement to reflect changes in underlying assumptions or factors of new information, data or methods, future events or other changes. For a further discussion of these and other factors that could impact our future results, performance or transactions, see "Risk Factors," including the risks incorporated herein and therein from our most recent Annual Report on Form 10-K filed with the SEC on February 27, 2015, as updated by our subsequent filings.

S-v


Table of Contents

WHERE YOU CAN FIND MORE INFORMATION

        We are subject to the information and reporting requirements of the Securities Exchange Act of 1934, as amended (the "Exchange Act") and, accordingly, file annual, quarterly and periodic reports, proxy statements and other information with the SEC. You may read and copy any reports, statements or other information we file with the SEC at the Public Reference Room of the SEC, 100 F Street, NE, Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the Public Reference Room. You may also obtain copies of this information by mail from the Public Reference Room of the SEC, 100 F Street, NE, Washington, D.C. 20549, at prescribed rates, or from commercial document retrieval services.

        We have filed with the SEC two registration statements on Form S-3, including exhibits and schedules filed with the registration statements of which this prospectus supplement is a part, under the Securities Act of 1933, as amended (the "Securities Act"), with respect to the shares of our common stock registered hereby. This prospectus supplement and the accompanying prospectuses do not contain all of the information set forth in the registration statements and exhibits and schedules to the registration statements. For further information with respect to our company and our shares of common stock registered hereby, reference is made to the registration statements, including the exhibits and schedules to the registration statements. Statements contained in this prospectus supplement and the accompanying prospectuses as to the contents of any contract or other document referred to in this prospectus supplement and the accompanying prospectuses are not necessarily complete and, where that contract is an exhibit to a registration statement, each statement is qualified in all respects by the exhibit to which the reference relates. Copies of the registration statements, including the exhibits and schedules to the registration statements, may be examined without charge at the Public Reference Room of the SEC, in the manner described above.

        Our SEC filings, including our registration statements, are also available to you, free of charge, on the SEC's website at www.sec.gov. Our SEC filings will also be available through the "Company—Investors—SEC Filings" tab of CyrusOne Inc.'s website at www.cyrusone.com. The information contained on or linked to or from our website is not incorporated by reference into this prospectus supplement or the accompanying prospectuses and is not considered part of this prospectus supplement or the accompanying prospectuses.

S-vi


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INCORPORATION BY REFERENCE

        The SEC allows us to "incorporate by reference" certain information into this prospectus supplement from certain documents that we filed with the SEC prior to the date of this prospectus supplement. By incorporating by reference, we are disclosing important information to you by referring you to documents we have filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus supplement, except for information incorporated by reference that is modified or superseded by information contained in this prospectus supplement or in any other subsequently filed document that also is incorporated by reference herein. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to be part of this prospectus supplement. These documents contain important information about us, our business and our finances. The following documents previously filed with the SEC are incorporated by reference into this prospectus supplement except for any document or portion thereof deemed to be "furnished" and not filed in accordance with SEC rules:

        We also incorporate by reference all documents we may file with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act on or after the date of this prospectus supplement and prior to the termination of the offering of securities covered by this prospectus supplement, except for any document or portion thereof deemed to be "furnished" and not filed in accordance with SEC rules. The information relating to us contained in this prospectus supplement does not purport to be comprehensive and should be read together with the information contained in the documents incorporated or deemed to be incorporated by reference herein.

        If you request, either orally or in writing, we will provide you with a copy of any or all documents that are incorporated by reference herein. Such documents will be provided to you free of charge, but will not contain any exhibits, unless those exhibits are incorporated by reference into the document. Requests can be made by writing to Investor Relations at 1649 West Frankford Road, Carrollton, Texas 75007. The documents may also be accessed on our website under the "Company—Investors—SEC Filings" tab at www.cyrusone.com. Information contained on our website is not incorporated by reference into this prospectus supplement or the accompanying prospectuses and is not considered part of this prospectus supplement or the accompanying prospectuses.

S-vii


Table of Contents

 

SUMMARY

        The following summary contains information about us and the offering. It does not contain all of the information that may be important to you in making a decision to purchase the common stock. For a more complete understanding of us and the common stock, we urge you to read this entire prospectus supplement, the accompanying prospectuses and the documents incorporated by reference herein carefully, including the "Risk Factors" section and the financial statements and the notes to those statements incorporated by reference herein. See "Where You Can Find More Information" and "Incorporation by Reference" in this prospectus supplement.

Our Company

        We are an owner, operator and developer of enterprise-class, carrier-neutral, multi-tenant data center properties. Our enterprise-class, carrier-neutral, multi-tenant data centers are purpose-built facilities with redundant power, cooling and access to a range of telecommunications carriers. They are not network-specific and enable customer interconnectivity to a range of telecommunications carriers. We provide mission-critical data center facilities that protect and ensure the continued operation of information technology ("IT") infrastructure for 679 customers in 27 operating data centers in 11 distinct markets (nine cities in the U.S., London and Singapore) as of March 31, 2015. We provide twenty-four-hours-a-day, seven-days-a-week security guard monitoring with customizable security features.

        Our goal is to be the preferred global data center provider to the Fortune 1000. As of March 31, 2015, our customers included nine of the Fortune 20 and 146 of the Fortune 1000 or private or foreign enterprises of equivalent size. These 146 customers provided 74% of our annualized rent as of March 31, 2015. Additionally, as of March 31, 2015, our top 10 customers represented 40% of our annualized rent.

        We cultivate long-term strategic relationships with our customers and provide them with solutions for their data center facilities and IT infrastructure challenges. Our offerings provide flexibility, reliability and security delivered through a tailored customer service focused platform that is designed to foster long-term relationships. We focus on attracting customers that have not historically outsourced their data center needs and providing them with solutions that address their current and future needs. Our facilities and construction design allow us to offer flexibility in density, power resiliency and the opportunity for expansion as our customers' needs grow. We also offer high-performance, low-cost data transfer and accessibility for our customers through our interconnection platform, CyrusOne National IX, which delivers interconnection across states and between metro-enabled sites within the CyrusOne facility footprint and beyond.

Our Portfolio

        As of March 31, 2015, our property portfolio included 27 data centers in 11 distinct markets (nine cities in the U.S., London and Singapore) collectively providing approximately 2,340,000 net rentable square feet ("NRSF"), of which 85% was leased, and powered by approximately 204 MW of universal power supply ("UPS") capacity. We own 17 of the buildings in which our data center facilities are located. We lease the remaining 10 buildings, which account for approximately 360,000 NRSF, or approximately 15% of our total operating NRSF. These leased buildings accounted for 20% of our total annualized rent as of March 31, 2015. As of March 31, 2015, we also had approximately 904,000 NRSF under development, as well as an aggregate of approximately 499,000 NRSF of additional powered shell space under roof available for development. In addition, we have approximately 195 acres of land that are available for future data center shell development. Along with our primary product offering, leasing of colocation space, our customers are increasingly interested in ancillary office and other space.

 

S-1


Table of Contents

We believe our existing operating portfolio and development pipeline will allow us to meet the evolving needs of our existing customers and continue to attract new customers.

        The following tables provide an overview of our operating and development properties as of March 31, 2015.

 
   
   
   
   
   
   
   
   
   
  Powered
Shell
Available
for Future
Development
(NRSF)(k)
   
 
 
   
   
  Operating Net Rentable Square Feet (NRSF)(a)    
 
 
   
   
  Available
UPS
Capacity
(MW)(l)
 
Facilities(b)
  Metro
Area
  Annualized
Rent(c)
  Colocation
Space
(CSF)(d)
  CSF
Leased(e)
  CSF
Utilized(f)
  Office &
Other(g)
  Office &
Other
Leased(h)
  Supporting
Infrastructure(i)
  Total(j)  

Westway Park Blvd, Houston, TX

  Houston   $ 56,452,442     112,133     96 %   96 %   10,563     98 %   36,756     159,452     3,000     28  

(Houston West 1)

                                                                 

West Seventh Street, Cincinnati, OH

  Cincinnati     38,151,863     212,664     93 %   94 %   5,744     100 %   171,561     389,969     37,000     13  

(7th St.)***

                                                                 

S. State Hwy 121 Business Lewisville, TX

  Dallas     34,874,104     108,687     96 %   96 %   11,374     97 %   59,345     179,406         18  

(Lewisville)*

                                                                 

W. Frankford Road, Carrollton, TX

  Dallas     27,115,401     170,627     84 %   86 %   25,435     84 %   69,464     265,526     272,000     18  

(Frankford)

                                                                 

Southwest Fwy, Houston, TX

  Houston     26,676,013     63,469     76 %   76 %   23,259     51 %   24,927     111,655         14  

(Galleria)

                                                                 

Kingsview Dr., Lebanon, OH

  Cincinnati     19,865,984     65,303     76 %   87 %   44,886     72 %   52,950     163,139     65,000     14  

(Lebanon)

                                                                 

South Ellis Street, Chandler, AZ

  Phoenix     19,751,706     77,504     96 %   97 %   34,501     11 %   39,129     151,134     31,000     27  

(Phoenix 1)

                                                                 

Westover Hills Blvd, San Antonio, TX

  San Antonio     18,401,018     43,843     100 %   100 %   5,989     83 %   45,606     95,438     11,000     12  

(San Antonio 1)

                                                                 

Industrial Road, Florence, KY

  Cincinnati     14,958,513     52,698     100 %   100 %   46,848     87 %   40,374     139,920         9  

(Florence)

                                                                 

Westway Park Blvd, Houston, TX

  Houston     13,286,621     79,492     70 %   79 %   3,355     62 %   55,018     137,865     12,000     12  

(Houston West 2)

                                                                 

Metropolis Drive, Austin, TX

  Austin     11,144,269     43,772     88 %   91 %   708     100 %   22,867     67,347         5  

(Austin 2)

                                                                 

Knightsbridge Drive, Hamilton, OH

  Cincinnati     9,722,776     46,565     77 %   78 %   1,077     100 %   35,336     82,978         10  

(Hamilton)*

                                                                 

South Ellis St. Chandler, AZ

  Phoenix     6,005,806     36,522     100 %   100 %   5,540     36 %   20,784     62,846     4,000     6  

(Phoenix 2)

                                                                 

Parkway Dr., Mason, OH

  Cincinnati     5,983,589     34,072     100 %   100 %   26,458     98 %   17,193     77,723         4  

(Mason)

                                                                 

E. Ben White Blvd., Austin, TX

  Austin     5,851,932     16,223     87 %   87 %   21,476     100 %   7,517     45,216         2  

(Austin 1)****

                                                                 

Midway Rd., Carrollton, TX

  Dallas     5,408,662     8,390     100 %   100 %               8,390         1  

(Midway)**

                                                                 

Kestral Way

  London     4,698,021     10,000     99 %   99 %               10,000         1  

(London)**

                                                                 

Springer Street, Lombard, IL

  Chicago     2,266,276     13,516     70 %   70 %   4,115     100 %   12,230     29,861     29,000     3  

(Lombard)

                                                                 

Marsh Ln., Carrollton, TX

  Dallas     2,247,795     4,245     100 %   100 %               4,245         1  

(Marsh Ln)**

                                                                 

Goldcoast Drive, Cincinnati, OH

  Cincinnati     1,480,977     2,728     100 %   100 %   5,280     100 %   16,481     24,489     14,000     1  

(Goldcoast)

                                                                 

Bryan St., Dallas, TX

  Dallas     863,855     3,020     51 %   51 %               3,020         1  

(Bryan St.)**

                                                                 

Westway Park Blvd., Houston, TX

  Houston     835,008                 8,564     100 %   5,304     13,868          

(Houston West 3)

                                                                 

McAuley Place, Blue Ash, OH

  Cincinnati     494,852     6,193     39 %   39 %   6,950     100 %   2,166     15,309         1  

(Blue Ash)*

                                                                 

E. Monroe Street, South Bend, IN

  South Bend     425,827     6,350     24 %   24 %           6,478     12,828     4,000     1  

(Monroe St.)

                                                                 

Crescent Circle, South Bend, IN

  South Bend     404,465     3,432     32 %   32 %           5,125     8,557     11,000     1  

(Blackthorn)*

                                                                 

Jurong East

  Singapore     295,479     3,200     19 %   19 %               3,200         1  

(Singapore)**

                                                                 

Ridgetop Circle, Sterling, VA

  Northern     4,955     37,461     48 %   71 %   1,160     100 %   38,047     76,668     6,000     6  

(Northern Virginia)

  Virginia                                                              

Total

      $ 327,668,209     1,262,109     87 %   89 %   293,282     76 %   784,658     2,340,049     499,000     204  

*
Indicates properties in which we hold a leasehold interest in the building shell and land. All data center infrastructure has been constructed by us and is owned by us.

**
Indicates properties in which we hold a leasehold interest in the building shell, land, and all data center infrastructure.

***
The information provided for the West Seventh Street (7th St.) property includes data for two facilities, one of which we lease and one of which we own.

****
During the three months ended March 31, 2015, we recognized an impairment charge of $8.6 million related to our exit from the Austin 1 facility, a property in which we hold a leasehold interest in the building shell and land. The impairment is attributable to the various assets that we will no longer be able to use once we exit this facility. The effective date of our lease termination is March 31, 2016.

 

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(a)
Represents the total square feet of a building under lease or available for lease based on engineers' drawings and estimates but does not include space held for development or space used by CyrusOne.

(b)
We may exercise early termination options at one or more of our leased facilities and migrate our customers to one of our owned facilities in those markets. If we were to do so, we may experience an asset impairment related to assets that we may choose to retire.

(c)
Represents monthly contractual rent (defined as cash rent including customer reimbursements for metered power) under existing customer leases as of March 31, 2015, multiplied by 12. For the month of March 2015, our total annualized rent was $327.7 million and customer reimbursements were $38.4 million annualized and consisted of reimbursements by customers across all facilities with separately metered power. Customer reimbursements under leases with separately metered power vary from month-to-month based on factors such as our customers' utilization of power and the suppliers' pricing of power. From April 1, 2013 through March 31, 2015, customer reimbursements under leases with separately metered power constituted between 8.9% and 14.2% of annualized rent. After giving effect to abatements, free rent and other straight-line adjustments, our annualized effective rent as of March 31, 2015 was $339.3 million. Our annualized effective rent was greater than our annualized rent as of March 31, 2015 because our positive straight-line and other adjustments and amortization of deferred revenue exceeded our negative straight-line adjustments due to factors such as the timing of contractual rent escalations and customer prepayments for services.

(d)
CSF represents the NRSF at an operating facility that is currently leased or readily available for lease as colocation space, where customers locate their servers and other IT equipment.

(e)
Percent leased is determined based on CSF being billed to customers under signed leases as of March 31, 2015 divided by total CSF. Leases signed but not commenced as of March 31, 2015 are not included.

(f)
Utilization is calculated by dividing CSF under signed leases for colocation space (whether or not the customer has occupied the space) by total CSF.

(g)
Represents the NRSF at an operating facility that is currently leased or readily available for lease as space other than CSF, which is typically office and other space.

(h)
Percent leased is determined based on Office & Other space being billed to customers under signed leases as of March 31, 2015 divided by total Office & Other space. Leases signed but not commenced as of March 31, 2015 are not included.

(i)
Represents infrastructure support space, including mechanical, telecommunications and utility rooms, as well as building common areas.

(j)
Represents the NRSF at an operating facility that is currently leased or readily available for lease. This excludes existing vacant space held for development.

(k)
Represents space that is under roof that could be developed in the future for operating NRSF, rounded to the nearest 1,000.

(l)
UPS capacity (also referred to as critical load) represents the aggregate power available for lease and exclusive use by customers from the facility's installed UPS, expressed in terms of megawatts. The capacity reported is for non-redundant megawatts, as we can develop flexible solutions to our customers at multiple resiliency levels. Does not sum to total due to rounding.

 

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(square feet rounded to nearest 1,000; dollars in millions)

 
  NRSF Under Development(a)    
  Under Development Costs(b)  
Facilities
  Metropolitan Area   Colocation
Space (CSF)
  Office &
Other
  Supporting
Infrastructure
  Powered
Shell(c)
  Total   UPS MW
Capacity(d)
  Actual
CapEx
to Date(e)
  Estimated
Costs to
Completion
  Total  

W. Frankford Rd.,

  Dallas     56,000         18,000         74,000     3.0   $ 4   $ 14 - 18   $ 18 - 22  

Carrollton, TX

                                                           

(Carrollton)

                                                           

Westover Hills Blvd.,

  San Antonio     30,000     20,000     25,000     49,000     124,000     3.0     27     13 - 16     40 - 43  

San Antonio, TX

                                                           

(San Antonio 2)

                                                           

Westway Park Blvd.,

  Houston     53,000         32,000     213,000     298,000     6.0     28     23 - 28     51 - 56  

Houston, TX

                                                           

(Houston West 3)

                                                           

South Ellis Street,

  Phoenix     36,000         4,000         40,000     6.0     8     9 - 12     17 - 20  

Chandler, AZ

                                                           

(Phoenix 2)

                                                           

Phoenix 3

  Phoenix                 150,000     150,000             11 - 13     11 - 13  

Metropolis Drive

  Austin     62,000     15,000     22,000     67,000     166,000     6.0     18     28 - 34     46 - 52  

(Austin 3)

                                                           

Ridgetop Circle,

  Northern Virginia     37,000         15,000         52,000         1     11 - 14     12 - 15  

Sterling, VA County

                                                           

(Northern VA)

                                                           

Total

        274,000     35,000     116,000     479,000     904,000     24.0   $ 86   $ 109 - 135   $ 195 - 221  

(a)
Represents NRSF at a facility for which activities have commenced or are expected to commence in the second and third quarters of 2015 to prepare the space for its intended use. Estimates and timing are subject to change.

(b)
Represents management's estimate of the total costs required to complete the current NRSF under development. There may be an increase in costs if customers require greater power density.

(c)
Represents NRSF under construction that, upon completion, will be powered shell available for future development into operating NRSF.

(d)
UPS Capacity (also referred to as critical load) represents the aggregate power available for lease to, and exclusive use by customers from the facility's installed UPS, expressed in terms of megawatts. The capacity presented is for non-redundant megawatts, as we can develop flexible solutions to our customers at multiple resiliency levels.

(e)
Actual capex-to-date is the cash investment as of March 31, 2015. There may be accruals above this amount for work completed, for which cash has not yet been paid.

 

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Our Competitive Strengths

        Our ability to attract and retain the world's largest customers is attributed to the following competitive strengths, which distinguish us from other data center operators and will enable us to continue to grow our operations.

        High Quality Customer Base.    The high quality of our assets combined with our reputation for serving the needs of large enterprises has enabled us to focus on the Fortune 1000 to build a quality customer base. We currently have 679 customers from a broad spectrum of industries, including nine of the Fortune 20 and 146 of the Fortune 1000 or private or foreign enterprises of equivalent size. While our history as a data center operator in Houston has helped us establish a particular expertise in serving the energy industry, as our geographical footprint has expanded, we have also experienced significant growth in other industries. Our revenue is generated by a stable enterprise customer base, as evidenced by the following as of March 31, 2015:

        As of March 31, 2015, no single customer represented more than 6.4% of our annualized rent, and our top 10 customers represented 40% of our annualized rent.

        Strategically Located Portfolio.    Our portfolio is located in several domestic and international markets possessing attractive characteristics for enterprise-focused data center operations. We have domestic properties in five of the top 10 largest U.S. cities by population (Chicago, Dallas, Houston, Phoenix and San Antonio), according to the U.S. Census Bureau, and four of the top 10 cities for Fortune 500 headquarters (Chicago, Cincinnati, Dallas and Houston), according to Forbes. We have recently expanded into Northern Virginia, which supports our strategy of growing our Fortune 1000 customer base by establishing a presence on the East Coast, while enhancing the geographic diversity of our portfolio. We believe cities with large populations or a large number of corporate headquarters are likely to produce incremental demand for IT infrastructure. In addition, being located close to our current and potential customers provides chief information officers ("CIOs") with additional confidence when outsourcing their data center infrastructure to us.

        Modern, High Quality, Flexible Facilities.    Our portfolio includes highly efficient, reliable facilities with flexibility to customize customer solutions and accessibility to hundreds of connectivity providers. To optimize the delivery of power, our properties include modern engineering technologies designed to minimize unnecessary power usage and, in our newest facilities, we are able to provide power utilization efficiency ratios we believe to be among the best in the multi-tenant data center industry. Fortune 1000 CIOs are dividing their application stacks into groups as some applications require 100% availability while others may require significant power to support complex computing or robust connectivity. Our construction design enables us to deliver different power densities and resiliencies to the same customer footprint, allowing customers to tailor solutions to meet their application needs. In addition, the National IX Platform provides access to hundreds of telecommunication and Internet carriers.

        Massively Modular® Construction Methods.    Our Massively Modular® design principles allow us to efficiently stage construction on a large scale and deliver critical power and colocation square feet ("CSF") in a timeframe that we believe is one of the best in the industry. We acquire or build a large powered shell capable of scaling with our customers' power and colocation space needs. The powered

 

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shell can be acquired or constructed for a relatively inexpensive capital cost. Once the building shell is ready, we can build individual data center halls in portions of the building space to meet the needs of customers on a modular basis. This modular data center hall construction can be completed in 12 to 16 weeks to meet our customers' immediate needs. This short construction timeframe ensures a very high utilization of the assets and minimizes the time between our capital investment and the receipt of customer revenue, favorably impacting our return on investment while also translating into lower costs for our customers. Our design principles also allow us to add incremental equipment to increase power densities as our customers' power needs increase, which provides our customers with a significant amount of flexibility to manage their IT demands. We believe this Massively Modular approach allows us to respond to rapidly evolving customer needs, to commit capital toward the highest return projects and to develop state-of-the-art data center facilities.

        Significant Leasing Capability.    Our focus on the customer, our ability to scale with their needs, and our operational excellence provides us with embedded future growth from our customer base. We signed new leases representing $16.6 million in annualized revenue during the three months ended March 31, 2015, excluding estimates for pass-through power and installation charges, with our previously existing customers accounting for approximately 76% of this amount. Since March 31, 2014, we have increased our operational NRSF by approximately 280,000 square feet or 14%, while maintaining a high percentage of NRSF leased of 85%, as of March 31, 2015.

        Significant, Attractive Expansion Opportunities.    As of March 31, 2015, we had an aggregate of approximately 499,000 NRSF of powered shell available for future development in the Southwest (333,000 NRSF), Midwest (160,000 NRSF) and Northern Virginia (6,000 NRSF) and approximately 195 acres of land available for future data center facility development. Our current development properties and available acreage were selected based on extensive site selection criteria and the collective industry knowledge and experience of our management team with a focus on markets with a strong presence of and high demand by Fortune 1000 companies. As a result, we believe that our development portfolio contains properties that are located in markets with attractive supply and demand conditions and that possess suitable physical characteristics to support data center infrastructure.

        Differentiated Reputation for Service.    We believe that the decision CIOs make to outsource their data center infrastructure has material implications for their businesses, and, as such, CIOs look to third-party data center providers that have a reputation for serving similar organizations and that are able to deliver a customized solution. We take a consultative approach to understanding the unique requirements of our customers, and our design principles allow us to deliver a customized data center solution to match their needs. We believe that this approach has helped fuel our growth. Our current customers are also often the source of new contracts, with referrals being an important source of new customers.

        Experienced Management Team.    Our management team is comprised of individuals drawing on diverse knowledge and skill sets acquired through extensive experiences across relevant industries, including the real estate, telecommunications and mission-critical infrastructure industries. Our senior management team of eight individuals has an average of more than 15 years of experience in the data center and communications industries.

        Balance Sheet Positioned to Fund Continued Growth.    As of March 31, 2015, we had $321.0 million in available liquidity, including $295.0 million in borrowing capacity under our unsecured revolving credit facility. The recently amended credit agreement governing our revolving credit facility and term loan has, as of June 22, 2015, a total commitment of $950.0 million (an increase from the prior total commitment of $600.0 million) and also includes an accordion feature that allows us to request an increase in our aggregate borrowing capacity by up to an additional $250.0 million, subject to receiving commitments from lenders. See "—Recent Developments—Credit Agreement Amendment and

 

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Borrowings and Additional Guarantors." We believe that we are appropriately capitalized with sufficient financial flexibility and capacity to fund future growth.

        Experienced Sales Force with Robust Partner Channel.    We have an experienced sales force with a particular expertise in selling to large enterprises, which can require extensive consultation and result in long sales cycles while these enterprises make their initial outsourcing decision. As of March 31, 2015, we had 33 sales-related employees. We believe the depth, knowledge and experience of our sales team differentiates us from other data center companies and allows us to be less dependent on brokers to identify and acquire customers. To complement our direct sales efforts, we have developed a robust network of more than 120 partners, including value added resellers, systems integrators and hosting providers.

Business and Growth Strategies

        Our objective is to grow our revenue and earnings and maximize stockholder returns and cash flow by continuing to expand our data center infrastructure outsourcing business.

        Increasing Revenue from Existing Customers and Properties.    We have historically generated a significant portion of our revenue growth from our existing customers. We signed new leases representing $55.0 million and $16.6 million in annualized revenue during 2014 and the three months ended March 31, 2015, respectively, excluding estimates for pass-through power and installation charges, while our previously existing customers accounted for approximately 58% and 76% of this new lease annualized revenue, respectively, during such periods. Products and services that did not include additional data center space accounted for approximately 27% and 10% of the new lease annualized revenue during 2014 and the three months ended March 31, 2015, respectively. On a monthly recurring rent weighted basis, 72% and 78% of the new lease annualized revenue during 2014 and the three months ended March 31, 2015, respectively, contained rent escalators at a weighted average annual rate of 2.7% and 2.5%, respectively. We will continue to target our existing customers because we believe that many have significant data center infrastructure needs that have not yet been outsourced, and many will require additional data center space and power to support their growth and their increasing reliance on technology infrastructure in their operations. To address new demand, we had approximately 358,000 NRSF available for lease as of March 31, 2015. We also had approximately 904,000 NRSF under development and an aggregate of approximately 499,000 NRSF of additional powered shell space under roof available for development as of March 31, 2015. We believe this space will support up to approximately 960,000 incremental CSF. In addition, we had approximately 195 acres of land that were available for future data center shell development as of March 31, 2015. We believe the development of this acreage will support up to approximately 2,970,000 incremental CSF.

        Attracting and Retaining New Customers.    Increasingly, enterprises are beginning to recognize the complexities of managing data center infrastructure in the midst of rapid technological development and innovation. We believe that these complexities, brought about by the rapidly increasing levels of Internet traffic and data, obsolete existing corporate data center infrastructures, increased power and cooling requirements and increased regulatory requirements, are driving the need for companies to outsource their data center facility requirements. Consequently, this will significantly increase the percentage of companies that use third-party data center colocation services over the next several years. We believe that our high quality assets and reputation for serving large enterprises have been, and will be, key differentiators for us in attracting customers that are outsourcing their data center infrastructure needs.

        We acquire customers through a variety of channels. We have historically managed our sales process through a direct-to-the-customer model but are now utilizing third-party leasing agents and indirect leasing channels to expand our universe of potential new customers. Over the past few years, we have developed a robust network of more than 120 partners in our indirect leasing channels

 

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including value added resellers, systems integrators and hosting providers. These channels, in combination with our award-winning internal marketing team, have enabled us to build both a strong brand and outreach program to new customers. Throughout the life cycle of a customer's lease with us, we maintain a disciplined approach to monitoring their experience, with the goal of providing the highest level of customer service. This personal attention fosters a strong relationship and trust with our customers, which leads to future growth and leasing renewals.

        Expanding into New Markets.    Our expansion strategy focuses on developing new data centers in markets where our customers are located and in markets with a strong presence of and high demand by Fortune 1000 customers. We conduct extensive analysis to ensure an identified market displays strong data center fundamentals, independent of the demand presented by any particular customer. In addition, we consider markets where our existing customers want us to be located. We regularly meet with our customers to understand their business strategies and potential data center needs. Our strategy of broadening our geographic footprint and expanding into markets with a strong presence of and high demand by Fortune 1000 customers is what led us to our recent expansion into the Northern Virginia and New York metropolitan markets. We believe that this approach combined with our Massively Modular® construction design reduces the risk associated with expansion into new markets because it provides strong visibility into our leasing opportunities and helps to ensure targeted returns on new developments. When considering a new market, we take a disciplined approach in evaluating potential business, property and site acquisitions, including a site's geographic attributes, availability of telecommunications and connectivity providers, access to power and expected costs for development.

        Growing Interconnection Business.    In April 2013, we launched the National IX Platform, delivering interconnection across states and between metro-enabled sites within the CyrusOne facility footprint and beyond. The platform enables high-performance, low-cost data transfer and accessibility for customers seeking to connect between CyrusOne facilities, from CyrusOne to their own private data center facility, or with one another via private peering, cross connects and/or public switching environments. Interconnection within a facility or on the National IX Platform allows our customers to share information and conduct commerce in a highly efficient manner not requiring a third-party intermediary and at a fraction of the cost normally required to establish such a connection between two enterprises. As of March 31, 2015, 62% of our annualized rent came from customers with footprints in multiple CyrusOne data centers, and the National IX Platform provides an easy and low-cost method for these customers to connect between facilities. Our quarterly interconnection revenue increased from $2.5 million to $4.5 million, or approximately 77%, from the first quarter of 2013 to the first quarter of 2015. The demand for interconnection creates additional rental and revenue growth opportunities for us, and we believe that customer interconnections increase our likelihood of customer retention by providing an environment not easily replicated by competitors. Since April 2013, we believe the National IX Platform has helped us sign colocation leases in excess of $100.0 million in total contracted revenue. We act as a trusted neutral party that enterprises, carriers and content companies utilize to connect to each other. We believe that the reputation and industry relationships of our executive management team place us in an ongoing trusted provider role. In 2014, we became the first colocation provider in North America to receive multi-site certification from the Open-IX Association, a non-profit industry group formed to promote better standards for data center interconnection and Internet Exchanges in North America.

Our Structure

        We intend to contribute the net proceeds from the sale of 6,918,597 shares of our common stock in this offering to our operating partnership in exchange for 6,918,597 newly issued operating partnership units in accordance with the partnership agreement of our operating partnership. We intend to contribute the net proceeds from the sale of 81,403 shares of our common stock in this offering to CyrusOne GP. CyrusOne GP intends to subsequently contribute such proceeds to our

 

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operating partnership in exchange for 81,403 newly issued operating partnership units in accordance with the partnership agreement of our operating partnership (our contribution of proceeds to our operating partnership and CyrusOne GP (and CyrusOne GP's subsequent contribution of proceeds to our operating partnership) and our operating partnership's subsequent issuance of operating partnership units to us and to CyrusOne GP are collectively referred to as the "OP Contribution and Issuance"). Our operating partnership intends to use the proceeds from the OP Contribution and Issuance, together with the net proceeds from the Credit Agreement Borrowings (as defined herein) and the Additional Debt Financing (as defined herein), to finance the Cervalis Acquisition, to pay fees and expenses related to the Cervalis Acquisition and for general corporate purposes. In the event we do not consummate the Cervalis Acquisition, we expect our operating partnership to use the proceeds from the OP Contribution and Issuance to repay outstanding indebtedness under our revolving credit facility and for general corporate purposes.

        We intend to use the net proceeds from the sale of 4,300,000 shares of our common stock in this offering (or 5,995,000 shares if the underwriters exercise their option to purchase additional shares of our common stock in full) to acquire 4,300,000 (or 5,995,000, as applicable) operating partnership units from Data Centers South Holdings LLC ("DCSH"), a Delaware limited liability company and subsidiary of CBI (the "CBI Repurchase").

        Upon the consummation of this offering (assuming no exercise by the underwriters of their option to purchase additional shares of our common stock), the OP Contribution and Issuance and the CBI Repurchase, our ownership of our operating partnership will increase from 80.2% to 87.9%.

 

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        The following diagram depicts our ownership structure as of June 15, 2015, after giving effect to this offering (assuming no exercise by the underwriters of their option to purchase additional shares of our common stock) and the corresponding issuance of operating partnership units to us and CyrusOne GP and acquisition of operating partnership units by us pursuant to the OP Contribution and Issuance and the CBI Repurchase, respectively:

GRAPHIC


(1)
If the underwriters exercise their option to purchase up to an additional 1,695,000 shares of our common stock in full, CBI would own approximately 8.7% of the outstanding partnership units in our operating partnership.

 

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Tax Status

        We have elected to be treated as a REIT for U.S. federal income tax purposes. In order to maintain our qualification as a REIT under the Code, we are required, among other things, to distribute at least 90% of our REIT taxable income to our stockholders on an annual basis, determined without regard to the dividends paid deduction and excluding any net capital gains. As a REIT, we are generally not subject to corporate level U.S. federal income tax on the earnings distributed currently to our stockholders. If we fail to qualify as a REIT in any taxable year and do not qualify for certain statutory relief provisions, we would be subject to U.S. federal income tax at regular corporate rates and would be precluded from re-electing to be taxed as a REIT for the subsequent four taxable years following the year during which we lost our REIT qualification. Even if we qualify for taxation as a REIT, we may be subject to certain U.S. federal, state and local taxes on our income or property, and the income of our taxable REIT subsidiaries will be subject to taxation at regular corporate rates.

Restrictions on Ownership and Transfer of Our Stock

        Due to limitations on the concentration of ownership of REIT stock imposed by the Code, among other purposes, our charter provides for restrictions on ownership and transfer of our shares of stock, including, in general, prohibitions on any person actually or constructively owning more than 9.8% in value or number (whichever is more restrictive) of the outstanding shares of our common stock or 9.8% in value of the outstanding shares of all classes or series of our stock. Our charter, however, permits exceptions to be made for stockholders provided that our board of directors determines such exceptions will not jeopardize our tax status as a REIT. Our board of directors has granted CBI exemptions from the ownership limits applicable to other holders of our common stock, subject to certain initial and ongoing conditions designed to protect our status as a REIT, including the receipt of an IRS private letter ruling or an opinion of counsel from a nationally recognized law firm that the exercise of any such exemption should not cause any rent payable by CBI to jeopardize our REIT status.

Recent Developments

The Pending Cervalis Acquisition

        On April 28, 2015, our operating partnership entered into an Agreement and Plan of Merger (the "Merger Agreement") by and among our operating partnership, Jupiter Merger Sub, LLC, a Delaware limited liability company and wholly owned subsidiary of our operating partnership ("Merger Sub"), Cervalis and LDG Holdings LLC, as representative for the sellers. The Merger Agreement provides for the acquisition of Cervalis by our operating partnership pursuant to the merger of Merger Sub with and into Cervalis, with Cervalis as the surviving entity (the "Merger"). Upon completion of the Merger, Cervalis will be an indirect, wholly owned subsidiary of CyrusOne. As a result of the Merger, we will acquire four Tier 3+ data center facilities and two work area recovery facilities (the "Cervalis Facilities") serving the New York metropolitan area.

        We will pay aggregate cash consideration of approximately $400.0 million in the Merger, excluding transaction related expenses, subject to customary closing adjustments. The Merger Agreement contains customary representations and warranties as well as covenants by each of the parties. The Merger is expected to close in the first week of July 2015, subject to the satisfaction of closing conditions, including among others the continuing accuracy of representations and warranties and compliance with covenants and agreements in the Merger Agreement. The closing of this offering is not conditioned upon the closing of the Cervalis Acquisition.

        The Cervalis Facilities currently comprise more than 500,000 gross square feet of space, including more than 130,000 CSF and over 100,000 square feet of work area recovery space. In the year ended December 31, 2014 and in the three months ended March 31, 2015, Cervalis generated revenues of

 

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approximately $69.0 million and $20.4 million, respectively, with approximately two-thirds of such revenues being derived from colocation services and the remainder from interconnection, managed services and work area recovery products. As of March 31, 2015, 78% of the CSF within the Cervalis Facilities was utilized. In addition to the currently available raised floor space, it currently has capacity under powered shell to deliver an incremental 50,000 CSF.

        The Cervalis Acquisition is expected to provide additional benefits to us, including the following:

Credit Agreement Amendment and Borrowings and Additional Guarantors

        On June 22, 2015, our operating partnership entered into an amendment (the "Amendment") to the credit agreement and other loan documents governing our senior unsecured revolving credit facility and senior unsecured term loan facility (the "Credit Agreement"). The Amendment, among other things, increased the size of the Credit Agreement's accordion feature, which gives our operating partnership the ability to request an increase in the total commitment under the Credit Agreement, from $300.0 million to $600.0 million. Subsequently, we exercised $350.0 million of this accordion feature and obtained commitments to increase the total commitment under the Credit Agreement from $600.0 million to $950.0 million, comprised of $650.0 million of commitments under our revolving credit facility and $300.0 million of commitments under our term loan. We intend to borrow an additional $150.0 million under the term loan on or prior to the closing of the Cervalis Acquisition (the "Credit Agreement Borrowings").

        We intend to use the Credit Agreement Borrowings, together with a portion of the net proceeds from this offering and the Additional Debt Financing (as defined herein), to finance the Cervalis Acquisition, to pay fees and expenses related to the Cervalis Acquisition and for general corporate purposes. In the event our operating partnership does not consummate the Cervalis Acquisition, we expect our operating partnership to use the proceeds from the OP Contribution and Issuance to repay outstanding indebtedness under our revolving credit facility and for general corporate purposes.

        In addition, upon the consummation of the Cervalis Acquisition, Cervalis and Cervalis LLC, a Delaware limited liability company and wholly owned subsidiary of Cervalis, will become guarantors under the Credit Agreement.

 

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Additional Debt Financing

        Subsequent to this offering, and subject to market conditions and other factors, we intend to pursue permanent debt financing in an aggregate principal amount of approximately $100.0 million (the "Additional Debt Financing"). We intend to use the net proceeds from the Additional Debt Financing, together with a portion of the net proceeds from this offering and the remaining net proceeds from the Credit Agreement Borrowings, to finance the Cervalis Acquisition, to pay fees and expenses related to the Cervalis Acquisition and for general corporate purposes. There can be no assurances that we will be able to complete the Additional Debt Financing as intended, and the closing of this offering is not conditioned upon the closing of the Additional Debt Financing. In the event we do not complete the Additional Debt Financing, we intend to borrow additional amounts under our revolving credit facility to finance the Cervalis Acquisition, to pay fees and expenses related to the Cervalis Acquisition and for general corporate purposes.

Corporate Information

        Our principal executive offices are located at 1649 West Frankford Road, Carrollton, Texas 75007. Our telephone number is (972) 350-0060.

 

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The Offering

        The following summary contains basic information about this offering. It does not contain all the information that is important to you. You should read this prospectus supplement, the accompanying prospectuses and the documents incorporated by reference carefully before making an investment decision.

Issuer

  CyrusOne Inc.

Common stock offered by us

 

11,300,000 shares(1)

Common stock to be outstanding after this offering

 

64,573,502 shares(2)

Common stock and operating partnership units to be outstanding after this offering

 

72,615,337 shares/operating partnership units(3)

Use of proceeds

 

We expect the net proceeds to us from the sale of common stock in this offering, after deducting estimated underwriting discounts, will be $324,592,500 (or $373,281,375 if the underwriters exercise their option to purchase additional shares of common stock in full).

 

We intend to contribute the net proceeds from the sale of 6,918,597 shares of our common stock in this offering to our operating partnership in exchange for 6,918,597 newly issued operating partnership units in accordance with the partnership agreement of our operating partnership. We intend to contribute the net proceeds from the sale of 81,403 shares of our common stock in this offering to CyrusOne GP. CyrusOne GP intends to subsequently contribute such proceeds to our operating partnership in exchange for 81,403 newly issued operating partnership units in accordance with the partnership agreement of our operating partnership. Our operating partnership intends to use the proceeds from the OP Contribution and Issuance, together with the net proceeds from the Credit Agreement Borrowings and the Additional Debt Financing, to finance the Cervalis Acquisition, to pay fees and expenses related to the Cervalis Acquisition and for general corporate purposes. In the event we do not consummate the Cervalis Acquisition, we expect our operating partnership to use the proceeds from the OP Contribution and Issuance to repay outstanding indebtedness under our revolving credit facility and for general corporate purposes. The closing of this offering is not conditioned upon the closing of the Cervalis Acquisition, which, if completed, will occur subsequent to the closing of this offering.

 

We intend to use the net proceeds from the sale of 4,300,000 shares of our common stock in this offering (or 5,995,000 shares if the underwriters exercise their option to purchase additional shares of our common stock in full) to acquire 4,300,000 (or 5,995,000, as applicable) operating partnership units from DCSH.

 

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NASDAQ symbol

 

CONE

Risk factors

 

Investing in our common stock involves a high degree of risk. See "Risk Factors" and all other information included or incorporated by reference into this prospectus supplement and the accompanying prospectuses (including the "Risk Factors" under Item 1A of our Annual Report on Form 10-K for the fiscal year ended December 31, 2014, incorporated by reference herein) for a discussion of the factors you should carefully consider before deciding to invest in our common stock.


(1)
Includes 7,000,000 shares issued under the Universal Shelf Prospectus, the net proceeds from the sale of which we intend to use to fund the OP Contribution and Issuance, and 4,300,000 shares issued under the Common Stock Prospectus, the net proceeds from the sale of which we intend to use to fund the CBI Repurchase.

(2)
Excludes 1,695,000 shares issuable upon exercise of the underwriters' option to purchase additional shares, 1,440,358 shares reserved for issuance under our 2012 Long Term Incentive Plan and 191,495 shares reserved under our 2014 Employee Stock Purchase Plan.

(3)
Includes 8,041,835 operating partnership units outstanding pursuant to the consummation of the transactions relating to our formation in 2012 and initial public offering in 2013 that may, subject to the limits in the partnership agreement of our operating partnership, be exchanged for cash or, at our option, shares of our common stock on a one-for-one basis and excludes operating partnership units held by us and our subsidiaries.

 

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Summary Financial Data

        The following tables set forth summary financial information on a consolidated and combined historical basis. The financial information for the periods prior to our initial public offering on January 24, 2013 are deemed to be the financial information of the "Predecessor" and for the periods subsequent to January 24, 2013 are deemed to be the financial information of the "Successor" company. CyrusOne Inc. was formed on July 31, 2012, and prior to our initial public offering, we had minimal activity, consisting solely of deferred offering costs. The financial information of the "Predecessor" reflect the historical financial position, results of operations and cash flows of the data center activities and holdings of CBI for all periods presented. The Predecessor's historical information has been prepared on a "carve-out" basis from CBI's consolidated financial statements using the historical results of operations, cash flows, assets and liabilities attributable to the data center business and include allocations of income, expenses, assets and liabilities from CBI. These allocations reflect significant assumptions and do not fully reflect what the Predecessor's financial position, results of operations and cash flows would have been had the Predecessor been a stand-alone company during the periods presented. As a result, historical financial information is not necessarily indicative of our future results of operations, financial position and cash flows.

        The financial information presented below as of December 31, 2014 and December 31, 2013, for the year ended December 31, 2014, for the period ended January 23, 2013 (January 1, 2013 to January 23, 2013), the period ended December 31, 2013 (January 24, 2013 to December 31, 2013) and the year ended December 31, 2012 has been derived from the audited consolidated and combined financial statements included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2014, which is incorporated by reference into this prospectus supplement.

        The financial information presented below as of March 31, 2015 and for the three months ended March 31, 2015 and March 31, 2014 has been derived from the unaudited condensed consolidated and combined financial statements included in our Quarterly Report on Form 10-Q for the three months ended March 31, 2015, which is incorporated by reference into this prospectus supplement. The unaudited condensed consolidated financial statements contain all normal recurring adjustments necessary, in the opinion of management, to summarize the financial position and results for the periods presented. The historical operating results of our company for the three months ended March 31, 2015 are not necessarily indicative of the results that may be expected for a full year.

        The unaudited pro forma condensed combined financial information presented below as of March 31, 2015 and for the year ended December 31, 2014 and for the three months ended March 31, 2015 is based upon historical financial statements of CyrusOne and Cervalis, as adjusted to give effect to the Cervalis Acquisition and the related Credit Agreement Borrowings and additional draws on our revolving credit facility (without giving effect to this offering or the Additional Debt Financing). Such unaudited pro forma condensed combined financial information has been derived from the unaudited pro forma condensed combined financial statements included in our Current Report on Form 8-K filed with the SEC on June 22, 2015, which is incorporated by reference into this prospectus supplement. The unaudited pro forma condensed combined financial information is not necessarily indicative of what our financial position, operating results and other data would have been if the Cervalis Acquisition had actually been completed on the dates indicated, and is not intended to project such information for any future date or for any future period, as applicable.

        You should read the following summary financial information in conjunction with our audited and unaudited condensed consolidated financial statements and the related notes and "Management's Discussion and Analysis of Financial Condition and Results of Operations" contained in our Annual Report on Form 10-K for the fiscal year ended December 31, 2014 and in our Quarterly Report on Form 10-Q for the quarterly period ended March 31, 2015, and in the "Unaudited Pro Forma

 

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Condensed Combined Financial Information" contained in our Current Report on Form 8-K filed with the SEC on June 22, 2015, which are incorporated by reference into this prospectus supplement.

 
  Three Months Ended
March 31,
  Year Ended
December 31,
   
   
   
 
 
   
   
  Year Ended
December 31,
 
 
  January 24,
2013 to
December 31,
2013
  January 1,
2013 to
January 23,
2013
 
 
  2015
Pro
Forma
   
   
  2014
Pro
Forma
   
 
(Dollars in millions, except per share data)
  2015   2014   2014   2012  

Statement of Operations Data:

                                                 

Revenue

  $ 106.0   $ 85.7   $ 77.5   $ 399.0   $ 330.9   $ 248.4   $ 15.1   $ 220.8  

Costs and expenses:

                                                 

Property operating expenses

    41.5     32.3     27.7     153.7     124.5     88.4     4.8     76.0  

Sales and marketing

    3.6     2.9     3.0     15.7     12.8     9.9     0.7     9.7  

General and administrative

    10.0     9.1     7.3     38.3     34.6     26.5     1.5     20.7  

Depreciation and amortization

    36.7     31.1     27.6     139.4     118.0     89.9     5.3     73.4  

Restructuring costs(a)

                        0.7          

Transaction costs(b)

    0.2     0.1     0.1     1.3     1.0     1.3     0.1     5.7  

Transaction-related compensation

                            20.0      

Management fees charged by CBI(c)

                                2.5  

Loss on sale of receivables to affiliate(d)

                                3.2  

Asset impairments(e)

    8.6     8.6                 2.8         13.3  

Operating (loss) income

    5.4     1.6     11.8     50.6     40.0     28.9     (17.3 )   16.3  

Interest expense

    11.5     8.4     10.7     52.0     39.5     41.2     2.5     41.8  

Other income

                        (0.1 )        

Loss on extinguishment of debt(f)

                13.6     13.6     1.3          

Income tax (expense) benefit

    (0.6 )   (0.4 )   (0.4 )   (2.2 )   (1.4 )   (1.9 )   (0.4 )   5.1  

(Loss) income from continuing operations

    (6.7 )   (7.2 )   0.7     (17.2 )   (14.5 )   (15.4 )   (20.2 )   (20.4 )

(Loss) gain on sale of real estate improvements(g)

                        (0.2 )       0.1  

Net (loss) income

  $ (6.7 ) $ (7.2 ) $ 0.7   $ (17.2 ) $ (14.5 ) $ (15.6 ) $ (20.2 ) $ (20.3 )

Noncontrolling interest in net (loss) income

    (2.7 )   (2.9 )   0.5     (7.9 )   (6.7 )   (10.3 )        

Net (loss) income attributed to common shareholders

  $ (4.0 ) $ (4.3 ) $ 0.2   $ (9.3 ) $ (7.8 ) $ (5.3 )        

Per share data:

                                                 

Basic weighted average common shares outstanding

    36.9     36.9     20.9     29.2     29.2     20.9          

Diluted weighted average common shares outstanding

    36.9     36.9     20.9     29.2     29.2     20.9          

Basic and diluted loss per common share

  $ (0.11 ) $ (0.12 ) $ 0.00   $ (0.35 ) $ (0.30 ) $ (0.28 )        

Dividend declared per share

  $ 0.315   $ 0.315   $ 0.21   $ 0.84   $ 0.84   $ 0.64          

 

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  As of March 31,    
   
 
 
  As of December 31,  
 
  2015
Pro Forma
   
 
(Dollars in millions)
  2015   2014   2013  

Balance Sheet Data:

                         

Investment in real estate, net

  $ 1,263.3   $ 1,067.4   $ 1,051.4   $ 883.8  

Total assets

    2,089.2     1,576.6     1,586.5     1,506.8  

Debt(h)

    1,084.0     692.4     673.2     541.7  

Other financing arrangements(i)

    167.1     51.3     53.4     56.3  

Noncontrolling interest(j)

    241.0     245.0     256.3     455.6  

 

 
  Three Months
Ended
March 31,
  Year Ended December 31,  
 
   
   
  Successor   Predecessor  
(Dollars in millions)
  2015   2014   2014   2013(k)   2012  

Other Financial Data:

                               

Utilization Rate(l)

    89 %   89 %   88 %   85 %   78 %

Capital expenditures

  $ 49.2   $ 49.7   $ 284.2   $ 228.6   $ 228.3  

 

 
  Three Months Ended
March 31,
  Year Ended December 31,  
 
   
   
   
  Successor   Predecessor  
 
  2015
Pro Forma
  2015   2014   2014
Pro Forma
  2014   2013(k)   2012  

Funds from operations(m)

  $ 36.7   $ 31.0   $ 27.1   $ 115.3   $ 98.3   $ 54.6   $ 61.7  

Normalized funds from operations(m)

    37.7     31.9     27.2     130.2     112.9     78.7     67.4  

EBITDA(n)

    42.1     32.7     39.4     176.4     144.4     105.4     89.8  

Adjusted EBITDA(n)

    54.6     45.1     41.7     201.6     169.3     138.7     115.3  

(a)
Represents a restructuring charge recognized in 2013 as a result of moving certain administrative functions to the Company's corporate office.

(b)
Represents legal, accounting and consulting fees incurred in connection with formation transactions, our qualification as a REIT and completed and potential business combinations.

(c)
Represents management fees charged by CBI for services it provided to the Predecessor, including executive management, legal, treasury, human resources, accounting, tax, internal audit and IT services. See Note 16 to our audited combined financial statements included in our Annual Report on Form 10-K for the fiscal year ended December 31, 2014, which is incorporated by reference into this prospectus supplement.

(d)
Represents the sale by the Predecessor of most of its trade and other accounts receivable to Cincinnati Bell Funding LLC ("CBF"), a bankruptcy-remote subsidiary of CBI, at a 2.5% discount to the receivables' face value. Effective October 1, 2012, we terminated our participation in this program.

(e)
Represents asset impairments recognized on real estate related equipment in 2013 and on a customer relationship intangible and property and equipment primarily related to our GramTel Inc. acquisition in 2012.

(f)
Represents a loss of $13.6 million associated with the repurchase of senior notes and the write-off of deferred financing costs in 2014. The 2013 amount represents the termination of the financing obligations for two of our facilities by purchasing the properties from the former lessors. A loss of $1.3 million was recognized in 2013 upon the termination of these obligations.

(g)
Represents the (loss) gain that was recognized on the sale of equipment in connection with upgrading of the equipment at various data center facilities.

(h)
As of March 31, 2015, debt included $305.0 million of borrowings related to the Credit Agreement, $374.8 million of senior notes due 2022 and capital lease obligations. As of December 31, 2014, debt included increased borrowings of $285.0 million related to the Credit Agreement, partially offset by the repurchase of senior notes due 2022 with an aggregate face value of $150.2 million. As of December 31, 2013, debt consisted of our $525.0 million senior notes due 2022 and capital lease obligations.

 

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(i)
Other financing arrangements represent leases of real estate where we were involved in the construction of structural improvements to develop buildings into data centers. When we bear substantially all the construction period risk, such as managing or funding construction, we are deemed to be the accounting owner of the leased property. These transactions generally do not qualify for sale leaseback accounting due to our continued involvement in these data center operations. For these transactions, at the lease inception date, we recognize the fair value of the leased building as an asset in investment in real estate and as a liability in other financing arrangements.

(j)
Noncontrolling interest represents CBI's net investment in CyrusOne Inc., CyrusOne GP, CyrusOne LP and its subsidiaries.

(k)
Represents the combined results of the Predecessor for the period January 1, 2013 to January 23, 2013 and the Successor for the period January 24, 2013 to December 31, 2013.

(l)
We calculate utilization rate by dividing CSF under signed leases for available space (whether or not the customer has occupied the space) by total CSF. Utilization rate differs from percent leased presented elsewhere in this prospectus supplement because utilization rate excludes office space and supporting infrastructure net rentable square footage and includes CSF for signed leases whether or not the customer has occupied the space. Management uses utilization rate as a measure of CSF leased.

(m)
We calculate funds from operations ("FFO") as net (loss) income computed in accordance with U.S. GAAP before real estate depreciation and amortization, amortization of customer relationship intangibles, real estate impairments, customer relationship intangible impairments and (gain) loss on sale of real estate improvements. Because the value of the customer relationship intangibles is inextricably connected to the real estate acquired, we believe the amortization and impairments of such intangibles is analogous to real estate depreciation and impairments; therefore, we add the customer relationship intangible amortization and impairments back for similar treatment with real estate depreciation and impairments. Our customer relationship intangibles are primarily associated with the acquisition of Cyrus Networks, LLC in 2010 and, at the time of acquisition, represented 22% of the value of the assets acquired.


We calculate normalized funds from operations ("Normalized FFO") as FFO plus transaction-related compensation, loss on extinguishment of debt, restructuring charges, legal claim costs, transaction costs and lease exit costs.


Management uses FFO and Normalized FFO as supplemental performance measures because they provide performance measures that, when compared year over year, capture trends in occupancy rates, rental rates and operating costs. We also believe that, as widely recognized measures of the performance of REITs, these measures will be used by investors as a basis to compare our operating performance with that of other REITs.


However, because FFO and Normalized FFO exclude real estate depreciation and amortization, amortization of customer relationship intangibles, real estate impairments and customer relationship intangible impairments, and capture neither the changes in the value of our properties that result from use or from market conditions, nor the level of capital expenditures and leasing commissions necessary to maintain the operating performance of our properties, all of which have real economic effect and could materially impact our results from operations, the utility of FFO and Normalized FFO as measures of our performance is limited. Other REITs may not calculate FFO and Normalized FFO in the same manner. Accordingly, our FFO and Normalized FFO may not be comparable to others. Therefore, FFO and Normalized FFO should be considered only as supplements to net (loss) income as measures of our performance. FFO and Normalized FFO should not be used as measures of our liquidity or as indicative of funds available to fund our cash needs, including our ability to make distributions. FFO and Normalized FFO also should not be used as supplements to or substitutes for cash flow from operating activities computed in accordance with U.S. GAAP.

 

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        A reconciliation of net (loss) income to FFO and Normalized FFO is presented below:

 
   
   
   
  Year Ended December 31,    
 
 
   
  Three Months
Ended
March 31,
  Successor    
   
 
 
   
   
  Predecessor  
 
  2015
Pro Forma
  2014
Pro Forma
   
   
 
(Dollars in millions)
  2015   2014   2014   2013(1)   2012  

Net (loss) income

  $ (6.7 ) $ (7.2 ) $ 0.7   $ (17.2 ) $ (14.5 ) $ (35.8 ) $ (20.3 )

Real estate depreciation and amortization

    29.2     26.0     22.2     107.6     95.9     70.6     52.9  

Amortization of customer relationship intangibles

    5.6     3.6     4.2     24.9     16.9     16.8     16.0  

Real estate impairments

    8.6     8.6                 2.8     11.7  

Customer relationship intangible impairments

                            1.5  

(Gain) loss on sale of real estate improvements

                        0.2     (0.1 )

FFO

    36.7     31.0     27.1     115.3     98.3     54.6     61.7  

Transaction-related compensation

                        20.0      

Loss on extinguishment of debt

                13.6     13.6     1.3      

Restructuring charges

                        0.7      

Legal claim costs

                        0.7      

Transaction costs

    0.2     0.1     0.1     1.3     1.0     1.4     5.7  

Lease exit costs

    0.8     0.8                      

Normalized FFO

  $ 37.7   $ 31.9   $ 27.2   $ 130.2   $ 112.9   $ 78.7   $ 67.4  

(1)
Represents the combined results of the Predecessor for the period January 1, 2013 to January 23, 2013 and the Successor for the period January 24, 2013 to December 31, 2013.

(n)
We calculate EBITDA as net (loss) income as defined by U.S. GAAP plus interest expense, income tax (benefit) expense and depreciation and amortization. We calculate Adjusted EBITDA as EBITDA plus restructuring charges, legal claim costs, transaction costs, loss on sale of receivables to affiliate, non-cash compensation, asset impairments, loss on extinguishment of debt, lease exit costs, (gain) loss on sale of real estate improvements, and transaction-related compensation less other income. Other companies may not calculate EBITDA and Adjusted EBITDA in the same manner. Accordingly, our EBITDA and Adjusted EBITDA may not be comparable to others. Management uses EBITDA and Adjusted EBITDA as supplemental performance measures because they provide useful measures of assessing our results of operations. EBITDA and Adjusted EBITDA should be considered only as supplements to net (loss) income as measures of our performance and should not be used as substitutes for net (loss) income.

 

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        A reconciliation of net (loss) income to EBITDA and Adjusted EBITDA is presented below:

 
   
   
   
  Year Ended December 31,  
 
  Three Months Ended
March 31,
 
 
  Successor    
 
 
  Predecessor  
 
  2015
Pro Forma
   
   
  2014
Pro Forma
   
   
 
(Dollars in millions)
  2015   2014   2014   2013(1)   2012  

Net (loss) income

  $ (6.7 ) $ (7.2 ) $ 0.7   $ (17.2 ) $ (14.5 ) $ (35.8 ) $ (20.3 )

Interest expense

    11.5     8.4     10.7     52.0     39.5     43.7     41.8  

Income tax (benefit) expense

    0.6     0.4     0.4     2.2     1.4     2.3     (5.1 )

Depreciation and amortization

    36.7     31.1     27.6     139.4     118.0     95.2     73.4  

EBITDA

    42.1     32.7     39.4     176.4     144.4     105.4     89.8  

Restructuring charges

                        0.7      

Legal claim costs

                        0.7      

Transaction costs

    0.2     0.1     0.1     1.3     1.0     1.4     5.7  

Loss on sale of receivables to affiliate

                            3.2  

Non-cash compensation

    3.0     3.0     2.2     10.3     10.3     6.3     3.4  

Asset impairments

    8.6     8.6                 2.8     13.3  

Loss on extinguishment of debt

                13.6     13.6     1.3      

Lease exit costs

    0.7     0.7                      

(Gain) loss on sale of real estate improvements

                        0.2     (0.1 )

Transaction-related compensation

                        20.0      

Other income

                        (0.1 )    

Adjusted EBITDA

  $ 54.6   $ 45.1   $ 41.7   $ 201.6   $ 169.3   $ 138.7   $ 115.3  

(1)
Represents the combined results of the Predecessor for the period January 1, 2013 to January 23, 2013 and the Successor for the period January 24, 2013 to December 31, 2013.

 

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RISK FACTORS

        An investment in our common stock involves risks. You should carefully consider the risk factors incorporated by reference from our most recent Annual Report on Form 10-K, the risks discussed below and the other information contained in this prospectus supplement, the accompanying prospectuses and the documents we incorporate by reference herein before purchasing shares of our common stock. Some statements in this prospectus supplement, including statements in the following risk factors, constitute forward-looking statements. Please refer to the section entitled "Special Note Regarding Forward-Looking Statements."

Risks Related to Ownership of Our Common Stock

Our cash available for distribution to stockholders may not be sufficient to make distributions at expected levels, and we may need to borrow in order to make such distributions; consequently, we may not be able to make such distributions in full.

        If cash available for distribution generated by our assets is less than our estimate or if such cash available for distribution decreases in future periods from expected levels, our inability to make the expected distributions could result in a decrease in the market price of our common stock.

        Distributions made by us will be authorized and determined by our board of directors in its sole discretion out of funds legally available therefor and will be dependent upon a number of factors, including restrictions under applicable law and our capital requirements. We may not be able to make or sustain distributions in the future. To the extent that we decide to make distributions in excess of our current and accumulated earnings and profits, such distributions would generally be considered a return of capital for U.S. federal income tax purposes to the extent of the holder's adjusted tax basis in its shares. A return of capital is not taxable, but it has the effect of reducing the holder's adjusted tax basis in its investment. To the extent that distributions exceed the adjusted tax basis of a holder's shares, they will be treated as a gain from the sale or exchange of such stock. See "U.S. Federal Income Tax Considerations—Taxation of Stockholders—Taxation of Taxable U.S. Stockholders—Distributions" in the accompanying prospectuses. If we borrow to fund distributions, our future interest costs would increase, thereby reducing our earnings and cash available for distribution from what they otherwise would have been.

We have significant outstanding indebtedness that involves significant debt service obligations, limits our operational and financial flexibility, exposes us to interest rate fluctuations and exposes us to the risk of default under our debt obligations.

        As of March 31, 2015, after giving pro forma effect to this offering and the use of proceeds therefrom, the Credit Agreement Borrowings, $50.0 million of borrowings under our revolving credit facility since March 31, 2015 and additional draws on our revolving credit facility (in the event we do not complete the Additional Debt Financing) and the consummation of the Cervalis Acquisition, we would have had a total combined indebtedness, including capital lease obligations, of approximately $993.8 million and other financing arrangements of $167.1 million. We also would have the ability to borrow up to an additional $337.9 million under the Credit Agreement after giving effect to the Amendment to the Credit Agreement, net of outstanding letters of credit of approximately $7.1 million, subject to satisfying certain financial tests. As of June 22, 2015, after giving effect to the Amendment to the Credit Agreement, the Credit Agreement governing the revolving credit facility and the term loan contains an accordion feature that allows our operating partnership to request an increase in the total commitment by up to $250.0 million. There are no limits on the amount of indebtedness we may incur other than limits contained in the indenture governing our senior notes, the Credit Agreement or future agreements that we may enter into or as may be set forth in any policy limiting the amount of indebtedness we may incur adopted by CyrusOne's board of directors. A substantial level of

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indebtedness could have adverse consequences for our business, financial condition and results of operations because it could, among other things:

Future offerings of debt, which would be senior to our common stock upon liquidation, and/or preferred equity securities, which may be senior to our common stock for purposes of distributions or upon liquidation, may adversely affect the market price of our common stock.

        In the future, we may attempt to increase our capital resources by making additional offerings of debt or preferred equity securities, including medium-term notes, trust preferred securities, senior or subordinated notes and preferred stock. Upon liquidation, holders of our debt securities and shares of preferred stock and lenders with respect to other borrowings will receive distributions of our available assets prior to the holders of our common stock. Additional equity offerings may dilute the holdings of our existing stockholders or reduce the market price of our common stock, or both. Holders of our common stock are not entitled to preemptive rights or other protections against dilution. Our preferred stock, if issued, could have a preference on liquidating distributions or a preference on distribution payments that could limit our ability to make a distribution to the holders of our common stock.

        Because our decision to issue securities in any future offering will depend on market conditions and other factors beyond our control, we cannot predict or estimate the amount, timing or nature of our future offerings. Thus, our stockholders bear the risk of our future offerings reducing the market price of our common stock and diluting their stock holdings in us.

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Increases in market interest rates may cause potential investors to seek higher dividend yields and therefore reduce demand for our common stock and result in a decline in our stock price.

        One of the factors that may influence the price of our common stock is the dividend yield on our common stock (the amount of dividends as a percentage of the price of our common stock) relative to market interest rates. An increase in market interest rates, which are currently at low levels relative to historical rates, may lead prospective purchasers of our common stock to expect a higher dividend yield, which we may be unable or choose not to provide. Higher interest rates would likely increase our borrowing costs and potentially decrease the cash available for distribution. Thus, higher market interest rates could cause the market price of our common stock to decline.

The number of shares available for future sale could adversely affect the market price of our common stock.

        We cannot predict whether future issuances of shares of our common stock or the availability of shares of our common stock for resale in the open market will decrease the market price per share of our common stock. Sales of a substantial number of shares of our common stock in the public market, either by us or by holders of operating partnership units upon exchange of such operating partnership units for our common stock, or the perception that such sales might occur, could adversely affect the market price of the shares of our common stock. In addition, we registered shares of common stock that we have reserved for issuance under our 2012 Long Term Incentive Plan, and they can generally be freely sold in the public market, assuming any applicable restrictions and vesting requirements are satisfied. If any or all of these holders, including CBI, cause a large number of their shares to be sold in the public market, the sales could reduce the trading price of our common stock and could impede our ability to raise future capital on terms acceptable to us or at all.

The market price and trading volume of our common stock may be volatile.

        Prior to the completion of our initial public offering, there was not any public market for our common stock. Even with an active trading market for our common stock, the market price of our common stock may be volatile. In addition, the trading volume in our common stock may fluctuate and cause significant price variations to occur. If the market price of our common stock declines significantly, you may be unable to resell your shares at a profit or at all. We cannot provide any assurance that the market price of our common stock will not fluctuate or decline significantly in the future.

        Some of the factors that could negatively affect the market price of our common stock or result in fluctuations in the price or trading volume of our common stock include:

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Our earnings and cash distributions will affect the market price of shares of our common stock.

        To the extent that the market value of a REIT's equity securities is based primarily upon market perception of the REIT's growth potential and its current and potential future cash distributions, whether from operations, sales, acquisitions, development or refinancing and is secondarily based upon the value of the underlying assets, shares of our common stock may trade at prices that are higher or lower than the net asset value per share. To the extent we retain operating cash flow for investment purposes, working capital reserves or other purposes rather than distributing the cash flow to stockholders, these retained funds, while increasing the value of our underlying assets, may negatively impact the market price of our common stock. Our failure to meet market expectations with regard to future earnings and cash distributions would likely adversely affect the market price of our common stock.

If CBI tendered all of its operating partnership units for redemption and we elected to acquire such units in exchange for shares of our common stock, CBI would own approximately 13.7% of our issued and outstanding common stock, after giving effect to this offering and the use of proceeds therefrom. The resale of such shares into the market, or the issuance of shares by us if we elected to acquire operating partnership units directly from CBI, could have an adverse effect on the trading price of our common stock and our ability to engage in concurrent capital raising initiatives.

        As of June 15, 2015, after giving effect to this offering and the use of proceeds therefrom and assuming the underwriters do not exercise their option to purchase additional shares of our common stock, CBI would have owned approximately 2.9% of our common stock and approximately 11.1% of our operating partnership's operating partnership units. We may issue shares (i) in exchange for operating partnership units held by CBI pursuant to its contractual rights (an "Exchange"), and/or (ii) in a primary offering, the proceeds of which would be used by us to acquire operating partnership units directly from CBI (a "Redemption"). In connection with an Exchange and subject to the limitations described in the partnership agreement, CBI will be able to exchange those operating partnership units for shares of our common stock, and any exchange of all or a substantial amount of its operating partnership units would result in CBI owning a significant percentage of our common stock. See "Description of the Partnership Agreement of CyrusOne LP—Redemption/Exchange Rights" in the accompanying prospectuses. If all of the operating partnership units currently held by CBI are tendered for redemption and we elected to acquire such units in exchange for shares of our common stock, CBI would currently own approximately 13.7% of our common stock, after giving effect to this offering and the use of proceeds therefrom. The interests of CBI as an investor in our securities may differ from or conflict with the interests of our other stockholders. CBI may seek to sell the shares of our common stock it receives in connection with an Exchange into the public market as soon as market conditions are favorable and, if CBI sells a large number of its shares into the public market or if we elect to issue shares in connection with a Redemption, such sales or issuances could reduce the trading price of our common stock and/or impede our ability to engage in concurrent capital raising initiatives.

Risks Related to the Proposed Cervalis Acquisition

We cannot assure you that the proposed Cervalis Acquisition will be completed.

        There are a number of risks and uncertainties relating to the Cervalis Acquisition. For example, the Cervalis Acquisition may not be completed, or may not be completed in the time frame, on the

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terms or in the manner currently anticipated, as a result of a number of factors, including the failure of the parties to satisfy one or more of the conditions to closing. There can be no assurance that the conditions to closing of the Cervalis Acquisition will be satisfied or waived or that other events will not intervene to delay or result in the failure to close the Cervalis Acquisition. The Merger Agreement may be terminated by the parties thereto under certain circumstances, including, without limitation, if the Cervalis Acquisition has not been completed by July 31, 2015 (subject to certain limited exceptions). Delays in closing the Cervalis Acquisition or the failure to close the Cervalis Acquisition at all may result in our incurring significant additional costs in connection with such delay or termination of the Merger Agreement and/or failing to achieve the anticipated benefits of the Cervalis Acquisition. Any delay in closing or a failure to close the Cervalis Acquisition could have a negative impact on our business and the trading price of our common stock.

        In addition, in the event the Cervalis Acquisition is not consummated, we would have issued additional shares of our common stock in this offering without realizing a corresponding increase in earnings and cash flow from acquiring the Cervalis Facilities. In the event the Cervalis Acquisition is not consummated, we expect our operating partnership to use the proceeds from the OP Contribution and Issuance to repay outstanding indebtedness under our revolving credit facility and for general corporate purposes. However, our operating partnership would also have broad authority to use the net proceeds of this offering for other purposes that may not be accretive to our earnings per share and funds from operations per share.

If completed, the Cervalis Acquisition may not achieve its intended benefits or may disrupt our plans and operations.

        There can be no assurance that we will be able to successfully integrate Cervalis with our business or otherwise realize the expected benefits of the Cervalis Acquisition. Our ability to realize the anticipated benefits of the Cervalis Acquisition will depend, to a large extent, on our ability to integrate Cervalis with our business. The combination of two independent businesses will be a complex, costly and time-consuming process. Our business may be negatively impacted following the Cervalis Acquisition if we are unable to effectively manage our expanded operations. The integration process will require significant time and focus from our management team following the Cervalis Acquisition and may divert attention from the day-to-day operations of the combined business. Additionally, consummation of the Cervalis Acquisition could disrupt our current plans and operations, which could delay the achievement of our strategic objectives.

        The expected synergies and operating efficiencies of the Cervalis Acquisition may not be fully realized, which could result in increased costs and have a material adverse effect on our business, financial condition, results of operations, cash flows and/or the trading price of our common stock. In addition, the overall integration of the businesses may result in material unanticipated problems, expenses, liabilities, competitive responses, loss of customer relationships and diversion of management's attention, among other potential adverse consequences. The risks of combining our operations of the businesses include, among others:

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        Many of these risks will be outside of our control and any one of them could result in increased costs, decreases in the amount of expected revenue and diversion of our management's time and energy, which could have a material adverse effect on our business, financial condition, results of operations and/or cash flows. In addition, even if our operations are integrated successfully with Cervalis', we may not realize the full benefits of the Cervalis Acquisition, including the synergies, operating efficiencies, or sales or growth opportunities that are expected. These benefits may not be achieved within the anticipated time frame or at all. All of these factors could cause dilution to our earnings per share, decrease or delay the expected accretive effect of the Cervalis Acquisition, and/or negatively impact the price of our common stock.

We may be subject to unknown or contingent liabilities related to Cervalis for which we may have limited recourse against the sellers.

        Cervalis may be subject to unknown or contingent liabilities for which we may have limited recourse against the sellers. Unknown or contingent liabilities might include liabilities for clean-up or remediation of environmental conditions, claims of customers, vendors or other persons dealing with the acquired entities, tax liabilities and other liabilities whether incurred in the ordinary course of business or otherwise. While the sellers are required to indemnify us with respect to breaches of representations and warranties, such indemnification is somewhat limited and subject to various survival periods, materiality thresholds, a deductible of $2.0 million and an aggregate cap on losses, with minimal exceptions, of $4.0 million.

        As a result, there can be no assurance that we will recover all amounts with respect to losses due to breaches of Cervalis' representations and warranties. In addition, the total amount of costs and expenses that we may incur with respect to liabilities associated with Cervalis may exceed our expectations, which may adversely affect our business, financial condition and results of operations.

The unaudited pro forma condensed combined financial information incorporated by reference into this prospectus supplement is presented for illustrative purposes only and is not necessarily indicative of what our financial position, operating results and other data would have been if the Cervalis Acquisition had actually been completed on the dates indicated and is not intended to project such information for any future date or for any future period, as applicable.

        The unaudited pro forma condensed combined financial information incorporated by reference into this prospectus supplement and the accompanying prospectuses that give effect to the Cervalis Acquisition is based on numerous assumptions and estimates underlying the adjustments described in the accompanying notes, which are based on available information and assumptions that our management considers reasonable. In addition, such unaudited pro forma condensed combined financial information does not reflect adjustments for other developments with our business or Cervalis' business after March 31, 2015. As a result, the unaudited pro forma condensed combined financial information does not purport to represent our financial condition that would have actually occurred had the Cervalis Acquisition occurred on March 31, 2015, represent the results of our operations that would have actually occurred had the Cervalis Acquisition occurred on January 1, 2014 or project our financial position or results of operations as of any future date or for any future period, as applicable.

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USE OF PROCEEDS

        We expect the net proceeds to us from the sale of common stock in this offering, after deducting estimated underwriting discounts, will be $324,592,500 (or $373,281,375 if the underwriters exercise their option to purchase additional shares of our common stock in full). The estimated offering expenses payable by us, exclusive of underwriting discounts, are approximately $0.4 million.

        We intend to contribute the net proceeds from the sale of 6,918,597 shares of our common stock in this offering to our operating partnership in exchange for 6,918,597 newly issued operating partnership units in accordance with the partnership agreement of our operating partnership. We intend to contribute the net proceeds from the sale of 81,403 shares of our common stock in this offering to CyrusOne GP. CyrusOne GP intends to subsequently contribute such proceeds to our operating partnership in exchange for 81,403 newly issued operating partnership units in accordance with the partnership agreement of our operating partnership. Our operating partnership intends to use the proceeds from the OP Contribution and Issuance, together with the net proceeds from the Credit Agreement Borrowings and the Additional Debt Financing, to finance the Cervalis Acquisition, to pay fees and expenses related to the Cervalis Acquisition and for general corporate purposes. In the event we do not consummate the Cervalis Acquisition, we expect our operating partnership to use the proceeds from the OP Contribution and Issuance to repay outstanding indebtedness under our revolving credit facility and for general corporate purposes. The closing of this offering is not conditioned upon the closing of the Cervalis Acquisition, which, if completed, will occur subsequent to the closing of this offering.

        As of March 31, 2015, we had $155.0 million outstanding under our revolving credit facility. As of June 15, 2015, we have approximately $205.0 million outstanding under our revolving credit facility. Our revolving credit facility currently bears interest at a rate of LIBOR + 1.70%. Our revolving credit facility is scheduled to mature in October 2018 and includes a one-year extension option, which if exercised by our operating partnership would extend the termination date to October 2019. The borrowings under our revolving credit facility that might be repaid with the net proceeds from this offering were used in October 2014 to repay amounts outstanding under our previous secured credit facility, which was terminated shortly thereafter, and for general corporate purposes, including the payment of dividends. Any borrowings under our revolving credit facility that are repaid with net proceeds from this offering may be reborrowed, subject to customary conditions.

        Affiliates of certain underwriters in this offering are lenders under our revolving credit facility. See "Underwriting—Relationships." To the extent that we use a portion of the net proceeds from this offering to repay borrowings outstanding under our revolving credit facility, such affiliates will receive their proportionate shares of any such amount.

        We intend to use the net proceeds from the sale of 4,300,000 shares of our common stock in this offering (or 5,995,000 shares if the underwriters exercise their option to purchase additional shares of our common stock in full) to acquire 4,300,000 (or 5,995,000, as applicable) operating partnership units from DCSH.

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CAPITALIZATION

        The following table sets forth our cash and cash equivalents and capitalization as of March 31, 2015:

        You should read this table in conjunction with "Use of Proceeds" and "Summary—Summary Financial Data" in this prospectus supplement and "Management's Discussion and Analysis of Financial Condition and Results of Operations—Financial Condition, Liquidity and Capital Resources"

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and our financial statements and the notes to our financial statements in the documents incorporated by reference herein.

 
  As of March 31, 2015  
(Dollars in millions)
  Actual   Pro forma   Pro forma
as adjusted
 

Cash and cash equivalents

  $ 26.0   $ 10.0   $ 70.2  

Debt:

                   

Capital lease obligations

  $ 12.6   $ 14.0   $ 14.0  

Other financing arrangements(1)

    51.3     167.1     167.1  

Term loan

    150.0     300.0     300.0  

6.375% Senior Notes due 2022

    374.8     374.8     374.8  

Revolving credit facility(2)

    155.0     395.2     255.0  

Equity:

                   

Preferred stock, $0.01 par value, 100,000,000 authorized; no shares issued or outstanding

             

Common stock, $0.01 par value, 500,000,000 shares authorized and 39,058,786 shares issued and outstanding, actual and pro forma; and 64,618,786 shares issued and outstanding, as adjusted for this offering and the April Equity Offering(3)

    0.4     0.4     0.7  

Additional paid in capital(3)

    518.9     518.9     887.1  

Accumulated deficit

    (72.5 )   (78.5 )   (78.5 )

Accumulated other comprehensive loss

    (0.6 )   (0.6 )   (0.6 )

Total CyrusOne Inc. stockholders' equity

    446.2     440.2     808.7  

Noncontrolling interest

    245.0     241.0     72.9  

Total equity

    691.2     681.2     881.6  

Total capitalization

  $ 1,434.9   $ 1,932.3   $ 1,992.5  

(1)
Other financing arrangements represents leases of real estate where we are involved in the construction of structural improvements to develop buildings into data centers. When we bear substantially all the construction period risk, such as managing or funding construction, we are deemed to be the accounting owner of the leased property. These transactions generally do not qualify for sale-leaseback accounting due to our continued involvement in these data center operations. For these transactions, at the lease inception date, we recognize the fair value of the leased building as an asset in investment in real estate and as a liability in other financing arrangements.

(2)
As of March 31, 2015, we had $155.0 million in outstanding borrowings under our revolving credit facility, leaving available borrowing capacity of $295.0 million. Subsequent to March 31, 2015, but prior to the effective date of the Amendment to the Credit Agreement and the Credit Agreement Borrowings, we borrowed an additional $50.0 million under our revolving credit facility. The numbers in the table above do not reflect this additional $50.0 million of borrowings.

(3)
Excludes 1,695,000 shares issuable upon the exercise of the underwriters' option to purchase additional shares.

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PRICE RANGE OF COMMON STOCK AND DIVIDENDS

        Our common stock is listed on the NASDAQ Global Select Market under the symbol "CONE." The following table sets forth the high and low sales prices of our common stock and the distributions we declared with respect to the periods indicated.

 
  Price Ranges(1)    
 
 
  Dividend
Declared
 
 
  High   Low  

2013

                   

First Quarter

  $ 23.71   $ 20.53   $ 0.16  

Second Quarter

  $ 24.84   $ 18.90   $ 0.16  

Third Quarter

  $ 22.22   $ 17.93   $ 0.16  

Fourth Quarter

  $ 22.94   $ 17.41   $ 0.16  

2014

                   

First Quarter

  $ 23.44   $ 20.21   $ 0.21  

Second Quarter

  $ 25.00   $ 19.52   $ 0.21  

Third Quarter

  $ 26.88   $ 23.64   $ 0.21  

Fourth Quarter

  $ 28.37   $ 23.59   $ 0.21  

2015

                   

First Quarter

  $ 32.86   $ 27.03   $ 0.315  

Second Quarter (through June 23, 2015)

  $ 32.84   $ 29.13   $ 0.315  

(1)
During the first quarter of 2013, we completed our initial public offering pursuant to a registration statement that became effective on January 17, 2013. As such, the price range for the first quarter of 2013 represents trading prices after January 17, 2013.

        On June 23, 2015, the last reported sale price of our common stock on the NASDAQ Global Select Market was $30.08 per share. As of June 15, 2015, CyrusOne Inc. had 219 stockholders of record and 53,273,502 outstanding shares.

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UNDERWRITING

        Citigroup Global Markets Inc., Goldman, Sachs & Co. and Morgan Stanley & Co. LLC are acting as representatives of the underwriters named below. Subject to the terms and conditions stated in the underwriting agreement dated the date of this prospectus supplement, each underwriter named below has severally agreed to purchase, and we have agreed to sell to that underwriter, the number of shares set forth opposite the underwriter's name.

Underwriter
  Number of
Shares
 

Citigroup Global Markets Inc. 

    1,922,356  

Goldman, Sachs & Co. 

    1,922,356  

Morgan Stanley & Co. LLC

    1,613,143  

KeyBanc Capital Markets Inc. 

    1,015,227  

Barclays Capital Inc. 

    922,928  

J.P. Morgan Securities LLC

    922,928  

Deutsche Bank Securities Inc. 

    646,055  

RBC Capital Markets, LLC

    599,905  

TD Securities (USA) LLC

    553,756  

Jefferies LLC

    369,170  

Stifel, Nicolaus & Company, Incorporated

    323,022  

SunTrust Robinson Humphrey, Inc. 

    276,884  

Raymond James & Associates, Inc. 

    212,270  

Total

    11,300,000  

        The underwriting agreement provides that the obligations of the underwriters to purchase the shares included in this offering are subject to approval of legal matters by counsel and to other conditions. The underwriters are obligated to purchase all the shares (other than those covered by the underwriters' option to purchase additional shares described below) if they purchase any of the shares.

        Shares sold by the underwriters to the public will initially be offered at the initial public offering price set forth on the cover of this prospectus supplement. Any shares sold by the underwriters to securities dealers may be sold at a discount from the initial offering price not to exceed $0.702 per share. If all the shares are not sold at the initial offering price, the underwriters may change the offering price and the other selling terms. Sales of shares made outside of the United States may be made by affiliates of the underwriters. The offering of the shares by the underwriters is subject to receipt and acceptance and subject to the underwriters' right to reject any order in whole or in part.

        We have granted to the underwriters an option, exercisable for 30 days from the date of this prospectus supplement, to purchase up to 1,695,000 additional shares at the public offering price less the underwriting discount. To the extent the option is exercised, each underwriter must purchase a number of additional shares approximately proportionate to that underwriter's initial purchase commitment. Any shares issued or sold under the option will be issued and sold on the same terms and conditions as the other shares that are the subject of this offering.

        We have agreed that, without the prior written consent of Citigroup Global Markets Inc., Goldman, Sachs & Co. and Morgan Stanley & Co. LLC, on behalf of the underwriters, we will not, for a period of 60 days from the date of this prospectus supplement, subject to certain exceptions:

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whether any such transaction described above is to be settled by delivery of common stock or such other securities, in cash or otherwise.

        All of our directors and executive officers and CBI have agreed that, without the prior written consent of Citigroup Global Markets Inc., Goldman, Sachs & Co. and Morgan Stanley & Co. LLC on behalf of the underwriters, they will not offer, sell or transfer any shares of common stock or any securities convertible into or exercisable or exchangeable for shares of common stock (including units in our operating partnership) beneficially owned by them for a period of 60 days from the date of this prospectus supplement, subject to certain exceptions.

        The shares are listed on the NASDAQ Global Select Market under the trading symbol "CONE."

        The following table shows the underwriting discounts that we are to pay to the underwriters in connection with this offering. These amounts are shown assuming both no exercise and full exercise of the underwriters' option.

 
  No Exercise   Full Exercise  

Per share

  $ 1.275   $ 1.275  

Total

  $ 14,407,500   $ 16,568,625  

        The estimated offering expenses payable by us, exclusive of the underwriting discounts, are approximately $0.4 million. We have also agreed to reimburse the underwriters for certain of their expenses in an amount not to exceed $10,000.

        In connection with this offering, the underwriters may purchase and sell shares in the open market. Purchases and sales in the open market may include short sales, purchases to cover short positions, which may include purchases pursuant to the underwriters' option to purchase additional shares, and stabilizing purchases.

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        Purchases to cover short positions and stabilizing purchases, as well as other purchases by the underwriters for their own accounts, may have the effect of preventing or retarding a decline in the market price of the shares. They may also cause the price of the shares to be higher than the price that would otherwise exist in the open market in the absence of these transactions. The underwriters may conduct these transactions on the NASDAQ Global Select Market, in the over-the-counter market or otherwise. If the underwriters commence any of these transactions, they may discontinue them at any time.

        In addition, in connection with this offering, some of the underwriters (and selling group members) may engage in passive market making transactions in the shares on the NASDAQ Global Select Market, prior to the pricing and completion of this offering. Passive market making consists of displaying bids on the NASDAQ Global Select Market no higher than the bid prices of independent market makers and making purchases at prices no higher than those independent bids and effected in response to order purchases by a passive market maker on each day are limited to a specified percentage of the passive market maker's average daily trading volume in the shares during a specified period and must be discontinued when that limit is reached. Passive market making may cause the price of the shares to be higher than the price that otherwise would exist in the open market in the absence of those transactions. If the underwriters commence passive market making transactions, they may discontinue them at any time.

Electronic Delivery

        A prospectus supplement and accompanying prospectuses in electronic format may be made available on the web sites maintained by one or more underwriters, or selling group members, if any, participating in this offering. The underwriters may agree to allocate a number of shares to underwriters and selling group members for sale to their online brokerage account holders. Internet distributions will be allocated by the representatives to underwriters and selling group members that may make Internet distributions on the same basis as other allocations.

Relationships

        The underwriters are full service financial institutions engaged in various activities, which may include securities trading, commercial and investment banking, financial advisory, investment management, principal investment, hedging, financing and brokerage activities. The underwriters and their respective affiliates have in the past performed commercial banking, investment banking and advisory services for us from time to time for which they have received customary fees and reimbursement of expenses and may, from time to time, engage in transactions with and perform services for us in the ordinary course of their business for which they may receive customary fees and reimbursement of expenses. In the ordinary course of their various business activities, the underwriters and their respective affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities), commodities, currencies and other financial instruments (which may include bank loans and/or credit default swaps) for their own account and for the accounts of their customers and may at any time hold long and short positions in such securities

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and instruments. The underwriters and their respective affiliates may also communicate independent investment recommendations, market color or trading ideas and/or publish or express independent research views in respect of such assets, securities or instruments and may at any time hold, or recommend to clients that they should acquire, long and/or short positions in such assets, securities and instruments. Such investment and securities activities may involve our securities and instruments.

        Affiliates of Citigroup Global Markets Inc., Goldman, Sachs & Co., Morgan Stanley & Co. LLC, Barclays Capital Inc., Deutsche Bank Securities, Inc., J.P. Morgan Securities LLC, KeyBanc Capital Markets Inc., RBC Capital Markets, LLC, TD Securities (USA) LLC, Raymond James & Associates, Inc., and SunTrust Robinson Humphrey, Inc. (underwriters in this offering) are lenders under our revolving credit facility. To the extent that we use a portion of the net proceeds from this offering to repay borrowings outstanding under our revolving credit facility, such affiliates of the underwriters will receive their proportionate shares of any such amount. Further, Stifel, Nicolaus & Company, Incorporated may pay an unaffiliated entity or its affiliate, who is also a lender under our revolving credit facility, a fee in connection with sales of shares of common stock in this offering. In addition, affiliates of Citigroup Global Markets Inc., Goldman, Sachs & Co., Morgan Stanley & Co. LLC, Barclays Capital Inc., J.P. Morgan Securities LLC, KeyBanc Capital Markets Inc., RBC Capital Markets, LLC, TD Securities (USA) LLC, Raymond James & Associates, Inc. and SunTrust Robinson Humphrey, Inc. (underwriters in this offering) hold commitments as lenders under our term loan, and an affiliate of Morgan Stanley & Co. LLC has served as a financial advisor to CyrusOne in connection with the Cervalis Acquisition. We intend to use a portion of the proceeds from this offering to finance the Cervalis Acquisition (see "Use of Proceeds") and a portion of the consideration for the Cervalis Acquisition will be used to repay outstanding borrowings under Cervalis' current credit facility. An affiliate of TD Securities (USA) LLC acts as administrative agent and is currently a lender under Cervalis' current credit facility. As a result, this affiliate of TD Securities (USA) LLC will receive its proportionate share of any amount of Cervalis' current credit facility that is repaid with the proceeds of this offering. In addition, an affiliate of Goldman, Sachs & Co. is a significant equityholder in Cervalis, and such affiliate will receive its proportionate equity share of the consideration for the Merger upon its consummation.

        We have agreed to indemnify the several underwriters against certain liabilities, including liabilities under the Securities Act, or to contribute to payments the underwriters may be required to make because of any of those liabilities.

Selling Restrictions

        Other than in the United States, no action has been taken by us or the underwriters that would permit a public offering of the securities offered by this prospectus supplement and the accompanying prospectuses in any jurisdiction where action for that purpose is required. The securities offered by this prospectus supplement and the accompanying prospectuses may not be offered or sold, directly or indirectly, nor may this prospectus supplement and the accompanying prospectuses or any other offering material or advertisements in connection with the offer and sale of any such securities be distributed or published in any jurisdiction, except under circumstances that will result in compliance with the applicable rules and regulations of that jurisdiction. Persons into whose possession this prospectus supplement and the accompanying prospectuses comes are advised to inform themselves about and to observe any restrictions relating to the offering and the distribution of this prospectus supplement and the accompanying prospectuses. This prospectus supplement and the accompanying prospectuses do not constitute an offer to sell or a solicitation of an offer to buy any securities offered by this prospectus supplement and the accompanying prospectuses in any jurisdiction in which such an offer or a solicitation is unlawful.

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Notice to Prospective Investors in Australia

        No placement document, prospectus, product disclosure statement or other disclosure document has been lodged with the Australian Securities and Investments Commission ("ASIC"), in relation to the offering. This prospectus supplement and the accompanying prospectuses do not constitute a prospectus, product disclosure statement or other disclosure document under the Corporations Act 2001 (the "Corporations Act") and do not purport to include the information required for a prospectus, product disclosure statement or other disclosure document under the Corporations Act.

        Any offer in Australia of the shares may only be made to persons (the "Exempt Investors") who are "sophisticated investors" (within the meaning of section 708(8) of the Corporations Act), "professional investors" (within the meaning of section 708(11) of the Corporations Act) or otherwise pursuant to one or more exemptions contained in section 708 of the Corporations Act so that it is lawful to offer the shares without disclosure to investors under Chapter 6D of the Corporations Act.

        The shares applied for by Exempt Investors in Australia must not be offered for sale in Australia in the period of 12 months after the date of allotment under the offering, except in circumstances where disclosure to investors under Chapter 6D of the Corporations Act would not be required pursuant to an exemption under section 708 of the Corporations Act or otherwise or where the offer is pursuant to a disclosure document which complies with Chapter 6D of the Corporations Act. Any person acquiring shares must observe such Australian on-sale restrictions.

        This prospectus supplement and the accompanying prospectuses contain general information only and do not take account of the investment objectives, financial situation or particular needs of any particular person. They do not contain any securities recommendations or financial product advice. Before making an investment decision, investors need to consider whether the information in this prospectus supplement and the accompanying prospectuses is appropriate to their needs, objectives and circumstances, and, if necessary, seek expert advice on those matters.

Notice to Prospective Investors in the Dubai International Financial Centre

        This prospectus supplement and the accompanying prospectuses relate to an Exempt Offer in accordance with the Offered Securities Rules of the Dubai Financial Services Authority ("DFSA"). This prospectus supplement and the accompanying prospectuses are intended for distribution only to persons of a type specified in the Offered Securities Rules of the DFSA. They must not be delivered to, or relied on by, any other person. The DFSA has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The DFSA has not approved this prospectus supplement and the accompanying prospectuses nor taken steps to verify the information set forth herein and has no responsibility for this prospectus supplement and the accompanying prospectuses. The shares to which this prospectus supplement and the accompanying prospectuses relate may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the shares offered should conduct their own due diligence on the shares. If you do not understand the contents of this prospectus supplement and the accompanying prospectuses you should consult an authorized financial advisor.

Notice to Prospective Investors in Hong Kong

        The shares have not been offered or sold and will not be offered or sold in Hong Kong, by means of any document, other than (a) to "professional investors" as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong and any rules made under that Ordinance; or (b) in other circumstances which do not result in the document being a "prospectus" as defined in the Companies Ordinance (Cap. 32) of Hong Kong or which do not constitute an offer to the public within the meaning of that Ordinance. No advertisement, invitation or document relating to the shares has been or may be issued or has been or may be in the possession of any person for the purposes of issue, whether in Hong Kong or elsewhere, which is directed at, or the contents of which are likely to be

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accessed or read by, the public of Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to shares which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" as defined in the Securities and Futures Ordinance and any rules made under that Ordinance.

Notice to Prospective Investors in Singapore

        This prospectus has not been registered as a prospectus with the Monetary Authority of Singapore. Accordingly, this prospectus and any other document or material in connection with the offer or sale, or invitation for subscription or purchase, of the shares may not be circulated or distributed, nor may the shares be offered or sold, or be made the subject of an invitation for subscription or purchase, whether directly or indirectly, to persons in Singapore other than (i) to an institutional investor (as defined under Section 4A of the Securities and Futures Act, Chapter 289 of Singapore (the "SFA")) under Section 274 of the SFA, (ii) to a relevant person (as defined in Section 275(2) of the SFA) pursuant to Section 275(1) of the SFA, or any person pursuant to Section 275(1A) of the SFA, and in accordance with the conditions specified in Section 275 of the SFA or (iii) otherwise pursuant to, and in accordance with the conditions of, any other applicable provision of the SFA, in each case subject to conditions set forth in the SFA.

        Where the shares are subscribed or purchased under Section 275 of the SFA by a relevant person which is a corporation (which is not an accredited investor (as defined in Section 4A of the SFA)) the sole business of which is to hold investments and the entire share capital of which is owned by one or more individuals, each of whom is an accredited investor, the securities (as defined in Section 239(1) of the SFA) of that corporation shall not be transferable for 6 months after that corporation has acquired the shares under Section 275 of the SFA except: (1) to an institutional investor under Section 274 of the SFA or to a relevant person (as defined in Section 275(2) of the SFA), (2) where such transfer arises from an offer in that corporation's securities pursuant to Section 275(1A) of the SFA, (3) where no consideration is or will be given for the transfer, (4) where the transfer is by operation of law, (5) as specified in Section 276(7) of the SFA, or (6) as specified in Regulation 32 of the Securities and Futures (Offers of Investments) (Shares and Debentures) Regulations 2005 of Singapore ("Regulation 32").

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LEGAL MATTERS

        Certain legal matters will be passed upon for us by Cravath, Swaine & Moore LLP and Skadden, Arps, Slate, Meagher & Flom LLP, and for the underwriters by Latham & Watkins LLP. Venable LLP will issue an opinion to us regarding certain matters of Maryland law, including the validity of the shares of our common stock offered hereby.

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EXPERTS

        The consolidated and combined financial statements, and the related financial statement schedules of CyrusOne Inc. and subsidiaries (the "Company"), incorporated in this prospectus supplement and accompanying prospectuses by reference from the Company's Annual Report on Form 10-K have been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report (which report expresses an unqualified opinion and includes an explanatory paragraph regarding the allocation of corporate costs from Cincinnati Bell Inc. for specified periods and the basis of presentation), which is incorporated herein by reference. Such financial statements and financial statement schedules have been so incorporated in reliance upon the report of such firm given upon their authority as experts in accounting and auditing.

        The consolidated financial statements, and the related financial statement schedules of Cervalis Holdings LLC, incorporated in this prospectus supplement and accompanying prospectuses by reference from the Company's Current Report on Form 8-K dated June 22, 2015, have been audited by McGladrey LLP, an independent registered public accounting firm, as stated in their report, which is incorporated herein by reference. Such financial statements and financial statement schedules have been so incorporated in reliance upon the report of such firm given upon their authority as experts in accounting and auditing.

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Prospectus

$600,000,000

LOGO

CyrusOne Inc.

DEBT SECURITIES

(and guarantees thereof)

COMMON STOCK

PREFERRED STOCK

WARRANTS

RIGHTS

UNITS

CyrusOne LP

CyrusOne Finance Corp.

DEBT SECURITIES

(and guarantees thereof)



         CyrusOne Inc. may, from time to time, offer and sell debt securities, common stock, preferred stock, warrants, rights and units, and certain of CyrusOne Inc.'s subsidiaries may guarantee the principal of, and premium (if any) and interest on, any such debt securities. CyrusOne LP and CyrusOne Finance Corp. may, from time to time, offer and sell debt securities, and CyrusOne Inc. and CyrusOne GP will, and certain of CyrusOne LP's subsidiaries including Cyrus One Foreign Holdings LLC, CyrusOne LLC and CyrusOne TRS Inc. may, guarantee the principal of, and premium (if any) and interest on, such debt securities.

         We refer to the debt securities and the guarantees thereof, common stock, preferred stock, warrants, rights and units of CyrusOne Inc. and the debt securities of CyrusOne LP and CyrusOne Finance Corp. and the guarantees thereof registered hereunder collectively as the "securities" in this prospectus. The securities will have a maximum aggregate offering price of $600,000,000 or the equivalent thereof in foreign currencies, foreign currency units or composite currencies.

         To assist us in complying with certain U.S. federal income tax requirements applicable to real estate investment trusts ("REITs"), among other purposes, our charter contains certain restrictions relating to the ownership and transfer of our stock, including an ownership limit of 9.8% of our outstanding common stock, subject to certain exceptions. See "Restrictions on Ownership and Transfer" for a detailed description of the ownership and transfer restrictions applicable to our stock.

         The specific terms of each series or class of the securities will be set forth in the applicable prospectus supplement. The applicable prospectus supplement will also contain information, where applicable, about certain federal income tax consequences relating to, and any listing on a securities exchange of, the securities covered by such prospectus supplement.

         The securities may be offered directly by us, through agents designated from time to time by us or to or through underwriters or dealers. If any agents, dealers or underwriters are involved in the sale of any of the securities, their names, and any applicable purchase price, fee, commission or discount arrangement between or among them will be set forth, or will be calculable from the information set forth, in the applicable prospectus supplement. See the sections entitled "Plan of Distribution" and "About this Prospectus" for more information. No securities may be sold without delivery of this prospectus and the applicable prospectus supplement describing the method and terms of the offering of such series of securities.

         Our common stock is listed on NASDAQ Global Select Market under the symbol "CONE." On March 20, 2014, the last reported sale price of our common stock on the NASDAQ Global Select Market was $21.86 per share. Our principal executive offices are located at 1649 West Frankford Road, Carrollton, TX 75007 and our telephone number is (972) 350-0060.

         We are an "emerging growth company" under the Jumpstart Our Business Startups Act of 2012. Investing in our common stock involves risk. See "Risk Factors" beginning on page 7.

         Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

The date of this prospectus is April 4, 2014


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TABLE OF CONTENTS

 
  Page  

Special Note Regarding Forward-Looking Statements

    1  

About this Prospectus

    3  

Where You Can Find More Information

    3  

Incorporation by Reference

    5  

Our Company

    6  

Risk Factors

    7  

Use of Proceeds

    7  

Ratio of Earnings to Consolidated and Combined Fixed Charges for CyrusOne Inc. and CyrusOne LP

    8  

Description of Debt Securities

    9  

Description of CyrusOne Inc. Common stock

    18  

Description of CyrusOne Inc. Preferred Stock

    20  

Description of Warrants

    23  

Description of Rights

    26  

Description of Units

    28  

Restrictions on Ownership and Transfer

    29  

Description of the Partnership Agreement of CyrusOne LP

    33  

Certain Provisions of Maryland Law and of Our Charter and Bylaws

    42  

U.S. Federal Income Tax Considerations

    49  

Plan of Distribution

    71  

Legal Matters

    74  

Experts

    74  

        Except as otherwise indicated or required by the context, references in this prospectus to (i) "CyrusOne," "we," "our," "us" and "our company" refer to CyrusOne Inc., a Maryland corporation, together with its combined subsidiaries, including CyrusOne LP, a Maryland limited partnership (our "operating partnership" or "CyrusOne LP"), and CyrusOne GP, a Maryland statutory trust of which we are the sole beneficial owner and sole trustee and which is the sole general partner of our operating partnership ("CyrusOne GP"), (ii) "CBI" refers to Cincinnati Bell Inc., an Ohio corporation, and, unless the context otherwise requires, its consolidated subsidiaries, and (iii) the number of common units of limited partnership interest ("operating partnership units") in CyrusOne LP gives effect to the approximately 2.8-to-1 operating partnership unit reverse split effected immediately prior to the completion of our initial public offering in January 2013 (the "IPO").

        You should rely only on the information contained in this prospectus, in an accompanying prospectus supplement or incorporated by reference herein or therein. We have not authorized anyone to provide you with information or make any representation that is different. If anyone provides you with different or inconsistent information, you should not rely on it. This prospectus and any accompanying prospectus supplement do not constitute an offer to sell or a solicitation of an offer to buy any securities other than the registered securities to which they relate, and this prospectus and any accompanying prospectus supplement do not constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction where, or to any person to whom, it is unlawful to make such an offer or solicitation. You should not assume that the information contained in this prospectus and any accompanying prospectus supplement is correct on any date after the respective dates of the prospectus and such prospectus supplement or supplements, as applicable, even though this prospectus and such prospectus supplement or supplements are delivered or securities are sold pursuant to the prospectus and such prospectus supplement or supplements at a later date. Since the respective dates of the prospectus contained in this registration statement and any accompanying prospectus supplement, our business, financial condition, results of operations and prospects may have changed. We may only use this prospectus to sell the securities if it is accompanied by a prospectus supplement.

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SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS

        This prospectus and the documents incorporated by reference herein contain forward-looking statements within the meaning of the federal securities laws. You can identify forward-looking statements by the use of forward-looking terminology such as "believes," "expects," "may," "will," "should," "seeks," "approximately," "intends," "plans," "estimates" or "anticipates" or the negative of these words and phrases or similar words or phrases which are predictions of or indicate future events or trends and which do not relate solely to historical matters. You can also identify forward-looking statements by discussions of strategy, plans or intentions.

        Forward-looking statements involve numerous risks and uncertainties and you should not rely on them as predictions of future events. Forward-looking statements depend on assumptions, data or methods which may be incorrect or imprecise and we may not be able to realize them. The following factors, among others, could cause actual results and future events to differ materially from those set forth or contemplated in the forward-looking statements:

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        While forward-looking statements reflect our good faith beliefs, they are not guarantees of future performance. We disclaim any obligation to publicly update or revise any forward-looking statement to reflect changes in underlying assumptions or factors of new information, data or methods, future events or other changes. For a further discussion of these and other factors that could impact our future results, performance or transactions, see the section in this prospectus entitled "Risk Factors," including the risks incorporated therein from our most recent Annual Report on Form 10-K filed with the Securities and Exchange Commission ("SEC") on March 3, 2014, as updated by our subsequent filings.

ABOUT THIS PROSPECTUS

        This prospectus is part of a registration statement that we filed with the SEC using a "shelf" registration process. Under this process, we may sell the securities described in this prospectus in one or more offerings up to a total dollar amount of $600,000,000. This prospectus provides you with a general description of the securities we may offer. Each time we sell securities, we will provide a prospectus supplement containing specific information about the terms of the applicable offering. Such prospectus supplement may add, update or change information contained in this prospectus. You should read this prospectus and the applicable prospectus supplement together with additional information described under the heading "Where You Can Find More Information."

        We may offer the securities directly, through agents, or to or through underwriters. The applicable prospectus supplement will describe the terms of the plan of distribution and set forth the names of any underwriters involved in the sale of the securities. See "Plan of Distribution" for more information. No securities may be sold without delivery of a prospectus supplement describing the method and terms of the offering of those securities.

WHERE YOU CAN FIND MORE INFORMATION

        We are subject to the information and reporting requirements of the Securities Exchange Act of 1934, as amended (the "Exchange Act"), and, accordingly, file annual, quarterly and periodic reports, proxy statements and other information with the SEC. You may read and copy any reports, statements or other information we file with the SEC at the Public Reference Room of the SEC, 100 F Street, NE, Washington, D.C. 20549. Please call the SEC at 1-800-SEC-0330 for further information on the operation of the Public Reference Room. You may also obtain copies of this information by mail from the Public Reference Room of the SEC, 100 F Street, NE, Washington, D.C. 20549, at prescribed rates, or from commercial document retrieval services.

        We have filed with the SEC a registration statement on Form S-3, including exhibits and schedules filed with the registration statement of which this prospectus is a part, under the Securities Act of 1933, as amended (the "Securities Act"), with respect to the securities registered hereby. This prospectus and any applicable prospectus supplement do not contain all of the information set forth in the registration statement and exhibits and schedules to the registration statement. For further information with respect to our company and the securities registered hereby, reference is made to the registration statement, including the exhibits and schedules to the registration statement. Statements contained in this prospectus and any applicable prospectus supplement as to the contents of any contract or other document referred to in this prospectus and any applicable prospectus supplement are not necessarily complete and, where that contract is an exhibit to the registration statement, each statement is qualified in all respects by the exhibit to which the reference relates. Copies of the registration statement, including the exhibits and schedules to the registration statement, may be examined without charge at the Public Reference Room of the SEC, in the manner described above.

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        Our SEC filings, including our registration statement, are also available to you, free of charge, on the SEC's website at www.sec.gov. Our SEC filings will also be available through the investor relations section of CyrusOne Inc.'s website at www.cyrusone.com. The information contained on or linked to or from our website is not incorporated by reference into this prospectus and should not be considered part of this prospectus or any applicable prospectus supplement.

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INCORPORATION BY REFERENCE

        This prospectus is part of a registration statement on Form S-3 filed with the SEC. This prospectus does not contain all of the information included in the registration statement, certain parts of which are omitted in accordance with the rules and regulations of the SEC.

        The SEC allows us to "incorporate by reference" certain information into this prospectus from certain documents that we filed with the SEC prior to the date of this prospectus. By incorporating by reference, we are disclosing important information to you by referring you to documents we have filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, except for information incorporated by reference that is modified or superseded by information contained in this prospectus or in any other subsequently filed document that also is incorporated by reference herein. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to be part of this prospectus. These documents contain important information about us, our business and our finances. The following documents previously filed with the SEC are incorporated by reference into this prospectus except for any document or portion thereof deemed to be "furnished" and not filed in accordance with SEC rules:

        We also specifically incorporate by reference any documents filed by us with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act after the date of the initial filing of this registration statement and prior to effectiveness of this registration statement.

        To the extent that any information contained in any Current Report on Form 8-K, or any exhibit thereto, is furnished to, rather than filed with, the SEC, such information or exhibit is specifically not incorporated by reference in this prospectus.

        The information relating to us contained in this prospectus does not purport to be comprehensive and should be read together with the information contained in the documents incorporated or deemed to be incorporated by reference into this prospectus.

        If you request, either orally or in writing, we will provide you with a copy of any or all documents that are incorporated by reference herein. Such documents will be provided to you free of charge, but will not contain any exhibits, unless those exhibits are incorporated by reference into the document. Requests can be made by writing to Investor Relations at 1649 West Frankford Road, Carrollton, TX 75007. The documents may also be accessed on our website under the Investor Relations tab at www.cyrusone.com. Information contained on our website is not incorporated by reference into this prospectus and you should not consider information contained on our website to be part of this prospectus or any applicable prospectus supplement.

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OUR COMPANY

        We are an owner, operator and developer of enterprise-class, carrier-neutral data center properties. Our data center properties are purpose-built facilities with redundant power, cooling and telecommunications systems. They are not network-specific and enable customer interconnectivity to a range of telecommunications carriers.

        We provide mission-critical data center facilities that protect and ensure the continued operation of information technology ("IT") infrastructure for approximately 600 customers in 25 operating data centers in 10 distinct markets (8 cities in the U.S., London and Singapore). Our goal is to be the preferred global data center provider to the Fortune 1000. As of December 31, 2013, our customers included nine of the Fortune 20 and 129 of the Fortune 1000 or private/ foreign enterprises of equivalent size. These 129 customers provided 75% of our annualized rent as of December 31, 2013.

        We cultivate long-term strategic relationships with our customers and provide them with solutions for their data center facilities and IT infrastructure challenges. Our offerings provide flexibility, reliability and security and are delivered through a tailored customer service focused platform that is designed to foster long-term relationships. We focus on attracting customers that have not historically outsourced their data center needs and providing them with solutions that address their current and future needs. The CyrusOne National IX Platform delivers interconnection across states and between metro-enabled sites within the CyrusOne facility footprint and beyond. The platform enables high-performance, low-cost data transfer and accessibility for customers by uniting all of our data centers.

        As of December 31, 2013, our property portfolio included 25 operating data centers in 10 distinct markets (8 cities in the U.S., London and Singapore) collectively providing approximately 1,975,000 Net Rentable Square Feet ("NRSF"), of which 82% was leased, and powered by approximately 158 megawatts ("MW") of universal power supplies capacity. We own 14 of the buildings in which our data center facilities are located. We lease the remaining 11 buildings, which account for approximately 375,000 NRSF, or approximately 19% of our total operating NRSF. These leased buildings accounted for 26% of our total annualized rent as of December 31, 2013. We also currently have 711,000 NRSF under development, as well as 626,000 NRSF of additional powered shell space under roof available for development. In addition, we have approximately 205 acres of land that are available for future data center shell development. Along with our primary product offering, leasing of colocation space, our customers are increasingly interested in ancillary office and other space. We believe our existing operating portfolio and development pipeline will allow us to meet the evolving needs of our existing customers and continue to attract new customers.

        Our business is comprised of the historical data center activities and holdings of CBI. CBI had operated its Cincinnati-based data center business for over 10 years; in addition, it acquired GramTel Inc. ("GramTel"), a data center operator in South Bend, Indiana and Chicago, Illinois, for approximately $20 million in December 2007; and it acquired Cyrus Networks, LLC ("Cyrus Networks"), a data center operator based in Texas, for approximately $526 million, net of cash acquired, in June 2010. On November 20, 2012, certain subsidiaries of CBI contributed certain assets and operations, including the assets and operations acquired through the GramTel and Cyrus Networks acquisitions, to our operating partnership.

        CyrusOne Inc. was formed as a Maryland corporation on July 31, 2012. On January 24, 2013, we completed the IPO of our common stock, issuing approximately 19.0 million shares for $337.1 million, net of underwriters' discount. On the same date, we purchased approximately 19.0 million operating partnership units with the proceeds of the IPO. In addition, CBI exchanged approximately 1.5 million operating partnership units for shares of our common stock, and CBI was issued 0.4 million shares of common stock as repayment for transaction costs paid by CBI in connection with our IPO. We also issued approximately 1.0 million shares of our common stock to our directors and employees. Vesting

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of these shares is contingent upon completion of service. Following the completion of these transactions, CyrusOne Inc. and CyrusOne GP held a combined 33.9% interest in our operating partnership, with the remaining 66.1% interest held by CBI. We intend to continue to operate in a manner that will allow us to qualify as a REIT commencing with our taxable year ended December 31, 2013, and we will make our REIT election upon filing of our 2013 federal income tax return.

        Our principal executive offices are located at 1649 West Frankford Road, Carrollton, TX 75007. Our telephone number is (972) 350-0060. We maintain a website, www.cyrusone.com. Other than with respect to those filings with the SEC that we have posted to our website and which are specifically identified as having been incorporated by reference herein, the information contained on, or accessible through, our website is not incorporated by reference into, and should not be considered a part of, this prospectus or any applicable prospectus supplement.

RISK FACTORS

        An investment in any securities offered by this prospectus involves risks. You should carefully consider the risk factors incorporated by reference to our most recent Annual Report on Form 10-K and the other information contained in this prospectus, as updated by our subsequent filings under the Exchange Act, before purchasing any of such securities. See "Where You Can Find More Information" for information about how to obtain a copy of these documents. You should also carefully consider the risks and other information that may be contained in, or incorporated by reference into, any prospectus supplement relating to the specific offering of securities.

USE OF PROCEEDS

        Unless otherwise set forth in a prospectus supplement, we plan to contribute the net proceeds from any sale of the securities by CyrusOne Inc. pursuant to this prospectus to our operating partnership in exchange for operating partnership units. Our operating partnership will subsequently use the net proceeds received from us, and any primary proceeds from offerings by our operating partnership, to potentially acquire or develop additional properties, to redeem outstanding operating partnership units and for general corporate purposes, which may include payment of distributions, the repayment of existing indebtedness, acquisitions and capital expenditures for improvements to the properties in our portfolio. Pending application of cash proceeds, we will invest the net proceeds in interest-bearing accounts and short-term, interest bearing securities that are consistent with our intention to continue to qualify as a REIT for federal income tax purposes. Further details regarding the use of the net proceeds of a specific series or class of the securities will be set forth in the applicable prospectus supplement.

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RATIO OF EARNINGS TO CONSOLIDATED AND COMBINED FIXED CHARGES FOR
CYRUSONE INC. AND CYRUSONE LP

 
   
  Year Ended December 31,  
 
  Successor   Predecessor  
(dollars in millions)
  January 24
to
December 31,
2013(a)
  January 1,
2013 to
January 23,
2013(a)(b)
  2012(a)(b)   2011(b)   2010(b)   2009(b)  

Pre-tax income (loss) from continuing operations before adjustment for non-controlling interests/minority interests in consolidated subsidiaries or income or loss from equity investees plus fixed charges*

  $ 30.8   $ (16.8 ) $ 19.9   $ 39.4   $ 19.2   $ 13.5  

Fixed charges:

                                     

Interest expensed and capitalized

    42.8     2.6     44.5     35.5     12     3.4  

Appropriate portion of rentals(c)

    2.2     0.5     2.9     2.4     1.2     0.3  

Total fixed charges

    45.0     3.1     47.4     37.9     13.2     3.7  

Ratio of earnings to fixed charges(d)(e)(f)

                1.0     1.5     3.6  

*
Earnings used in computing the ratio of earnings to combined fixed charges consists of income from continuing operations before income taxes, adjustment for non-controlling interests/minority interests, income/loss from equity method investees, and fixed charges except for capitalized interest.

(a)
Consolidated results for the period ended January 24, 2013 to December 31, 2013, and the combined results for the period ended January 1, 2013 to January 23, 2013 and the year ended December 31, 2012 are the same for both CyrusOne Inc. and CyrusOne LP.

(b)
Periods represent results of the Predecessor on a "carved-out basis" from CBI for all respective periods.

(c)
Represents the estimated portion of operating lease expense deemed to represent interest for each respective period presented.

(d)
For the period ended December 31, 2013 (January 24, 2013 to December 31, 2013), earnings were insufficient to cover fixed charges by $14.2 million.

(e)
For the period ended January 23, 2013 (January 1, 2013 to January 23, 2013), earnings were insufficient to cover fixed charges by $19.9 million.

(f)
For the year ended December 31, 2012, earnings were insufficient to cover fixed charges by $27.5 million.

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DESCRIPTION OF DEBT SECURITIES

        The following description of the debt securities outlines some of the provisions of the debt securities. This information may not be complete in all respects and is qualified in its entirety by reference to the applicable indenture and its associated documents, including the form of note. We have filed forms of the indentures with the SEC as exhibits to the registration statement of which this prospectus forms a part. See "Where You Can Find More Information" for information on how to obtain copies of them. The indentures will be qualified under the Trust Indenture Act of 1939. The specific terms of any series of debt securities will be described in the applicable prospectus supplement. If so described in a prospectus supplement, the terms of that series of debt securities may differ from the general description of terms presented below and the form of indenture filed as an exhibit to the registration statement of which this prospectus forms a part.

        Please note that, in this section titled "Description of Debt Securities," references to "we," "our" and "us" refer either to CyrusOne Inc., or, collectively, to CyrusOne LP and CyrusOne Finance Corp., as the case may be, as the issuer or issuers, as applicable, of the applicable series of debt securities and not to any subsidiaries, unless the context requires otherwise.

General

        The indentures do not limit the aggregate principal amount of debt securities that may be issued thereunder. The debt securities may be issued from time to time in one or more series.

        We will describe in the applicable prospectus supplement the terms relating to a series of debt securities, including:

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Conversion or Exchange Rights

        We will set forth in the prospectus supplement the terms on which a series of debt securities may be convertible into or exchangeable for CyrusOne Inc. common stock or other securities, including the conversion or exchange rate, as applicable, or how it will be calculated, and the applicable conversion or exchange period. We will include provisions as to whether conversion or exchange is mandatory, at the option of the holder or at our option. We may include provisions pursuant to which the number of our securities that the holders of the series of debt securities receive upon conversion or exchange would, under the circumstances described in those provisions, be subject to adjustment, or pursuant to which those holders would, under those circumstances, receive other property upon conversion or exchange, for example in the event of our merger or consolidation with another entity.

Certain Covenants

        The indenture may include covenants of CyrusOne Inc., CyrusOne LP, CyrusOne Finance Corp. or any of their subsidiaries, as the case may be. These covenants may impose limitations on our indebtedness, limitations on liens, limitations on the issuance of preferred stock of certain of our subsidiaries, limitations on certain distributions and limitations on transactions with our affiliates, or

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other limitations. Any such covenants applicable to a series of debt securities will be set forth in the prospectus supplement.

Consolidation, Merger or Sale

        The indentures in the forms initially filed as exhibits to the registration statement of which this prospectus is a part do not contain any covenant that restricts the ability of CyrusOne Inc., CyrusOne LP, CyrusOne Finance Corp. or any of their subsidiaries to merge or consolidate, or sell, convey, transfer or otherwise dispose of all or substantially all of their assets. However, any successor of such entity or acquiror of such assets must assume all of the obligations of CyrusOne Inc., CyrusOne LP, CyrusOne Finance Corp. or any of their subsidiaries, as applicable, under the indentures and the debt securities.

        If the debt securities are convertible into other securities of CyrusOne Inc., CyrusOne LP, CyrusOne Finance Corp. or any of their subsidiaries, as applicable, the person with whom such entity consolidates or merges or to whom such entity sells all of its property must make provisions for the conversion of the debt securities into securities similar to the debt securities which the holders of the debt securities would have received if they had converted the debt securities before the consolidation, merger or sale.

Guarantees

        The debt securities issued by CyrusOne Inc. may be fully and unconditionally guaranteed by certain subsidiaries of CyrusOne Inc. Unless otherwise described in the applicable prospectus supplement, the debt securities issued by CyrusOne LP and CyrusOne Finance Corp. will be fully and unconditionally guaranteed by CyrusOne Inc., CyrusOne GP and certain of CyrusOne LP's subsidiaries including Cyrus One Foreign Holdings LLC, CyrusOne LLC and CyrusOne TRS Inc. These guarantees will be joint and several obligations of the guarantors. If a series of debt securities is so guaranteed, an indenture, or a supplemental indenture thereto, will be executed by the guarantor. The obligations of each guarantor under its guarantee will be limited as necessary to prevent that guarantee from constituting a fraudulent conveyance under applicable law. The terms of the guarantee will be set forth in the applicable prospectus supplement.

Events of Default Under the Indentures

        Unless otherwise specified in the applicable prospectus supplement, the following are events of default under the indentures with respect to any series of debt securities that we may issue:

        If an event of default with respect to debt securities of any series occurs and is continuing, other than an event of default specified in the penultimate bullet point above, the trustee or the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series, by notice to

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us in writing, and to the trustee if notice is given by such holders, may, and the trustee at the request of the holders of at least 25% in aggregate principal amount of the outstanding debt securities of that series will, declare the unpaid principal, premium, if any, and accrued interest, if any, due and payable immediately. Upon a declaration of acceleration, such principal of, premium, if any, and accrued interest will be immediately due and payable. If an event of default specified in the penultimate bullet point above occurs with respect to us, the principal amount of and accrued interest, if any, of each series of debt securities then outstanding shall be due and payable without any notice or other action on the part of the trustee or any holder.

        The holders of a majority in principal amount of the outstanding debt securities of an affected series may waive any default or event of default with respect to the series and its consequences, except that defaults or events of default regarding payment of principal, premium, if any, or interest, require the consent of each holder affected by such waiver.

        The holders of at least a majority in principal amount of the outstanding debt securities of any series may direct the time, method and place of conducting any proceeding for any remedy available to the trustee or exercising any trust or power conferred on the trustee. However, the trustee may refuse to follow any direction that conflicts with law or the applicable indenture, that may involve the trustee in personal liability, or that the trustee determines in good faith may be unduly prejudicial to the rights of holders not joining in the giving of such direction and may take any other action it deems proper that is not inconsistent with any such direction received from holders of the applicable series of debt securities. A holder may not pursue any remedy with respect to the indenture or the debt securities unless:

        However, such limitations do not apply to the right of any holder of a debt security to receive payment of the principal of, premium, if any, or interest on, such debt security or to bring suit for the enforcement of any such payment on or after the due date expressed in the debt security, which right shall not be impaired or affected without the consent of the holder.

        We will periodically file statements with the trustee regarding our compliance with the covenants in the indentures.

Modifications of Indentures; Waiver

        Subject to certain limited exceptions, modifications, waivers and amendments of the indentures, the debt securities and the debt security guarantees may be made with the consent of the holders of not less than a majority in aggregate principal amount of the outstanding notes (including consents obtained in connection with a tender offer or exchange offer for the notes) and any past default or compliance with any provisions may also be waived with the consent of the holders of a majority in

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principal amount of the outstanding notes; provided that no such modification, waiver or amendment may, without the consent of each holder affected thereby:

        Modifications, waivers and amendments of the indentures, the debt securities and the debt security guarantees may, without notice to or the consent of any holder be made:

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Defeasance and Discharge

        We may at any time, at the option of the applicable board of directors evidenced by a board resolution set forth in an officers' certificate, elect to have all of our obligations discharged with respect to the outstanding debt securities of any series and all obligations of any guarantors discharged with respect to their guarantees ("Legal Defeasance") except for:

        In addition, we may, at our option and at any time, elect to have our obligations and the obligations of any guarantors released with respect to certain covenants to be described in the applicable indenture ("Covenant Defeasance") and thereafter any omission to comply with those covenants will not constitute a default or event of default with respect to the debt securities of the applicable series. In the event Covenant Defeasance occurs, all events of default (except those relating to payments on the debt securities of the applicable series or bankruptcy, receivership, rehabilitation or insolvency events with respect to us) will no longer constitute an event of default with respect to such debt securities.

        In order to exercise either Legal Defeasance or Covenant Defeasance:

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        Each indenture will be discharged and will cease to be of further effect as to all debt securities issued thereunder, when:

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Form, Exchange and Transfer

        We will issue the debt securities of each series only in fully registered form without coupons and, unless we otherwise specify in the applicable prospectus supplement, in minimum denominations of $2,000 and any integral multiples of $1,000 in excess of $2,000. The indentures provide that we may issue debt securities of a series in temporary or permanent global form and as book-entry securities that will be deposited with a depositary named by us and identified in a prospectus supplement with respect to that series.

        Subject to the terms of the indentures and the limitations applicable to global securities set forth in the applicable prospectus supplement, holders of the debt securities may present the debt securities for exchange or for registration of transfer, duly endorsed or with the form of transfer endorsed thereon duly executed if so required by us or the security registrar, at the office of the security registrar or at the office of any transfer agent designated by us for this purpose. Unless otherwise provided in the debt securities that the holder presents for transfer or exchange, the holder will be required to pay any related taxes or other governmental charges.

        We will name in the applicable prospectus supplement the security registrar, and any transfer agent in addition to the security registrar, that we initially designate for any debt securities.

        If we elect to redeem the debt securities of any series, we will not be required to:

Information Concerning the Trustee

        The trustee, other than during the occurrence and continuance of an event of default under an indenture, undertakes to perform only those duties as are specifically set forth in the applicable indenture. Upon an event of default under an indenture, the trustee must use the same degree of care as a prudent person would exercise or use in the conduct of his or her own affairs. Subject to this provision, the trustee is under no obligation to exercise any of the powers given it by the indentures at the request of any holder of debt securities unless it is offered reasonable security and indemnity against the costs, expenses and liabilities that it might incur.

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        The indentures and provisions of the Trust Indenture Act of 1939 contain limitations on the rights of the trustee, should it become a creditor of us or any guarantor, to obtain payment of claims in certain cases or to realize on certain property received by it in respect of any such claims, as security or otherwise. The trustee is permitted to engage in other transactions; provided that if it acquires any conflicting interest, it must eliminate such conflict or resign.

Payment and Paying Agents

        Unless we otherwise indicate in the applicable prospectus supplement, we will make payment of the interest on any debt securities on any interest payment date to the person in whose name the debt securities, or one or more predecessor securities, are registered at the close of business on the regular record date for the interest.

        We will pay principal of, and any premium and interest on, the debt securities of a particular series at the office of the paying agents designated by us, except that, unless we otherwise indicate in the applicable prospectus supplement, we may make payments of principal or interest by check which we will mail to the holder or by wire transfer to certain holders. The trustee will initially act as paying agent and registrar. We will name in the applicable prospectus supplement any other paying agents that we initially designate for the debt securities of a particular series.

Governing Law

        The indentures, the debt securities and any guarantees thereunder will be governed by and construed in accordance with the laws of the State of New York.

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DESCRIPTION OF CYRUSONE INC. COMMON STOCK

        The following summary of the terms of the common stock of our company does not purport to be complete and is subject to and qualified in its entirety by reference to the Maryland General Corporation Law (the "MGCL") and our charter and bylaws. Copies of our charter and bylaws have been filed with the SEC and are incorporated by reference as exhibits to the registration statement of which this prospectus is a part. See "Where You Can Find More Information."

        Our charter provides that we may issue up to 500,000,000 shares of common stock, $0.01 par value per share. Our charter authorizes our board of directors, without stockholder approval, to amend our charter to increase or decrease the aggregate number of shares of stock that we are authorized to issue or the number of authorized shares of any class or series of stock.

        As of March 21, 2014, there were 22,690,871 shares of our common stock issued and outstanding. Under Maryland law, our stockholders generally are not liable for our debts or obligations solely as a result of their status as stockholders.

        All shares of our common stock offered hereby will be duly authorized, fully paid and nonassessable. Subject to the preferential rights, if any, of holders of any other class or series of our stock and to the provisions of our charter relating to the restrictions on ownership and transfer of our stock, holders of our common stock are entitled to receive distributions when authorized by our board of directors and declared by us out of assets legally available for distribution to our stockholders and are entitled to share ratably in our assets legally available for distribution to our stockholders in the event of our liquidation, dissolution or winding up after payment of or adequate provision for all of our known debts and liabilities.

        Subject to the provisions of our charter regarding the restrictions on ownership and transfer of our stock and except as may be otherwise specified in the terms of any class or series of common stock, each outstanding share of common stock entitles the holder to one vote on all matters submitted to a vote of stockholders, including the election of directors, and, except as may be provided with respect to any other class or series of our stock, the holders of shares of our common stock possess the exclusive voting power. There is no cumulative voting in the election of directors. Consequently, the holders of a majority of the outstanding shares of our common stock can elect all of the directors then standing for election, and the holders of the remaining shares will not be able to elect any directors. Directors are elected by a plurality of all of the votes cast in the election of directors.

        Holders of shares of our common stock have no preference, conversion, exchange, sinking fund, redemption or appraisal rights and have no preemptive rights to subscribe for any securities of our company. Subject to the provisions of our charter regarding the restrictions on ownership and transfer of our stock, shares of our common stock have equal distribution, liquidation and other rights.

        Under the MGCL, a Maryland corporation generally cannot dissolve, amend its charter, merge or consolidate with, or convert to, another entity, sell all or substantially all of its assets or engage in a statutory share exchange unless the action is advised by the board of directors and approved by the affirmative vote of stockholders entitled to cast at least two-thirds of the votes entitled to be cast on the matter, unless a lesser percentage (but not less than a majority of all of the votes entitled to be cast on the matter) is specified in the corporation's charter. Our charter provides that these actions must be approved by a majority of all of the votes entitled to be cast on the matter.

        Maryland law also permits a corporation to transfer all or substantially all of its assets without the approval of its stockholders to an entity owned, directly or indirectly, by the corporation. Because our operating assets are held by our operating partnership's wholly owned subsidiaries, these subsidiaries may be able to merge or transfer all or substantially all of their assets without the approval of our stockholders.

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Power to Increase or Decrease Authorized Shares of Common Stock, Reclassify Unissued Shares of Common Stock and Issue Additional Shares of Common Stock

        Our charter authorizes our board of directors, with the approval of a majority of the entire board and without stockholder approval, to amend our charter to increase or decrease the aggregate number of shares of stock or the number of shares of any class or series of stock that we are authorized to issue. In addition, our charter authorizes our board of directors to authorize the issuance from time to time of shares of our common stock.

        Our charter also authorizes our board of directors to classify and reclassify any unissued shares of our common stock into other classes or series of stock, including one or more classes or series of stock that have priority over our common stock with respect to voting rights, distributions or upon liquidation, and authorize us to issue the newly classified shares. Prior to the issuance of shares of each new class or series, our board of directors is required by Maryland law and by our charter to set, subject to the provisions of our charter regarding the restrictions on ownership and transfer of our stock, the preferences, conversion and other rights, voting powers, restrictions, limitations as to distributions, qualifications and terms and conditions of redemption for each class or series. Therefore, although our board of directors does not currently intend to do so, it could authorize the issuance of shares of common stock with terms and conditions that could have the effect of delaying, deferring or preventing a change in control or other transaction that might involve a premium price for shares of our common stock or otherwise be in the best interests of our stockholders.

        We believe that the power of our board of directors to approve amendments to our charter to increase or decrease the number of authorized shares of stock, to authorize us to issue additional authorized but unissued shares of common stock and to classify or reclassify unissued shares of common stock and thereafter to authorize us to issue such classified or reclassified shares of stock provides us with increased flexibility in structuring possible future financings and acquisitions and in meeting other needs that might arise.

Restrictions on Ownership and Transfer

        To assist us in complying with certain U.S. federal income tax requirements applicable to REITs, among other purposes, our charter contains certain restrictions relating to the ownership and transfer of our stock, including an ownership limit of 9.8% of our outstanding common stock, subject to certain exceptions. Our board may, from time to time, grant waivers from these restrictions, in its sole discretion. See "Restrictions on Ownership and Transfer" on page 24.

Transfer Agent and Registrar

        The transfer agent and registrar for our common stock is Computershare Trust Company N.A.

Listing

        Our common stock is listed on the NASDAQ Global Select Market under the symbol "CONE."

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DESCRIPTION OF CYRUSONE INC. PREFERRED STOCK

        The following summary of the terms of the preferred stock of our company does not purport to be complete and is subject to and qualified in its entirety by reference to the MGCL and our charter and bylaws. Copies of our charter and bylaws have been filed with the SEC and are incorporated by reference as exhibits to the registration statement of which this prospectus is a part. See "Where You Can Find More Information." When we offer to sell a particular class or series of stock, we will describe the specific terms of the series in a prospectus supplement. Accordingly, for a description of the terms of any class or series of stock, you must refer to both the prospectus supplement relating to that class or series and the description of stock in this prospectus. To the extent the information contained in the prospectus supplement differs from this summary description, you should rely on the information in the prospectus supplement.

General

        Our charter provides that we may issue up to 100,000,000 shares of preferred stock, par value $0.01 per share. Our charter authorizes our board of directors, without stockholder approval, to amend our charter to increase or decrease the aggregate number of shares of stock that we are authorized to issue or the number of authorized shares of any class or series of stock. As of March 21, 2014, there were no shares of our preferred stock issued and outstanding. Under Maryland law, our stockholders generally are not liable for our debts or obligations solely as a result of their status as stockholders.

        All shares of our preferred stock offered hereby will be duly authorized, fully paid and nonassessable. The specific terms of a particular class or series of preferred stock will be described in the prospectus supplement relating to that class or series, including a prospectus supplement providing that preferred stock may be issuable upon the exercise of warrants we issue. The description of preferred stock set forth below and the description of the terms of a particular class or series of preferred stock set forth in the applicable prospectus supplement do not purport to be complete and are qualified in their entirety by reference to the articles supplementary relating to that class or series.

        The preferences and other terms of the preferred stock of each class or series will be fixed by the articles supplementary relating to such class or series. A prospectus supplement, relating to each class or series, will specify the terms of the preferred stock as follows:

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Rank

        Unless otherwise specified in the applicable prospectus supplement, the preferred stock will, with respect to dividend rights and rights upon liquidation, dissolution or winding up of our company, rank: (1) senior to all classes or series of our common stock, and to any other class or series of our stock expressly designated as ranking junior to the preferred stock; (2) on parity with any class or series of our stock expressly designated as ranking on parity with the preferred stock; and (3) junior to any other class or series of our stock expressly designated as ranking senior to the preferred stock.

Conversion Rights

        The terms and conditions, if any, upon which any shares of any class or series of preferred stock are convertible into our common stock will be set forth in the applicable prospectus supplement relating thereto. Such terms will include the number of shares of our common stock into which the shares of preferred stock are convertible, the conversion price (or manner of calculation thereof), the conversion period, provisions as to whether conversion will be at the option of the holders of such class or series of preferred stock, the events requiring an adjustment of the conversion price and provisions affecting conversion in the event of the redemption of such class or series of preferred stock.

Power to Increase or Decrease Authorized Shares of Preferred Stock, Reclassify Unissued Shares of Preferred Stock and Issue Additional Shares of Preferred Stock

        Our charter authorizes our board of directors, with the approval of a majority of the entire board and without stockholder approval, to amend our charter to increase or decrease the aggregate number of shares of stock or the number of shares of any class or series of stock that we are authorized to issue. In addition, our charter authorizes our board of directors to authorize the issuance from time to time of shares of our preferred stock.

        Our charter also authorizes our board of directors to classify and reclassify any unissued shares of our preferred stock into other classes or series of stock, including one or more classes or series of stock that have priority over our common stock with respect to voting rights, distributions or upon liquidation, and authorize us to issue the newly classified shares. Prior to the issuance of shares of each new class or series, our board of directors is required by Maryland law and by our charter to set, subject to the provisions of our charter regarding the restrictions on ownership and transfer of our stock, the preferences, conversion and other rights, voting powers, restrictions, limitations as to distributions, qualifications and terms and conditions of redemption for each class or series. Therefore, although our board of directors does not currently intend to do so, it could authorize the issuance of shares of preferred stock with terms and conditions that could have the effect of delaying, deferring or preventing a change in control or other transaction that might involve a premium price for shares of our common stock or otherwise be in the best interests of our stockholders. No shares of preferred stock are presently outstanding, and we have no present plans to issue any shares of preferred stock.

        We believe that the power of our board of directors to approve amendments to our charter to increase or decrease the number of authorized shares of stock, to authorize us to issue additional

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authorized but unissued shares of preferred stock and to classify or reclassify unissued shares of preferred stock and thereafter to authorize us to issue such classified or reclassified shares of stock provides us with increased flexibility in structuring possible future financings and acquisitions and in meeting other needs that might arise.

Restrictions on Ownership and Transfer

        To assist us in complying with certain U.S. federal income tax requirements applicable to REITs, among other purposes, our charter contains certain restrictions relating to the ownership and transfer of our stock, including an ownership limit of 9.8% in value of the aggregate of the outstanding shares of all classes or series of our stock, subject to certain exceptions. Our board may, from time to time, grant waivers from these restrictions, in its sole discretion. See "Restrictions on Ownership and Transfer" on page 24. We may choose to adopt similar restrictions with respect to any class or series offered pursuant to this prospectus under the articles supplementary for each such class or series. The applicable prospectus supplement will specify any additional ownership limitation relating to such class or series.

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DESCRIPTION OF WARRANTS

        We may issue warrants for the purchase of debt securities, common stock or preferred stock and may issue warrants independently or together with debt securities, common stock or preferred stock or attached to or separate from such securities. We will issue each series of warrants under a separate warrant agreement between us and a bank or trust company as warrant agent, as specified in the applicable prospectus supplement. To the extent the information contained in the prospectus supplement differs from this summary description, you should rely on the information in the prospectus supplement. The warrant agent will act solely as our agent in connection with the warrants and will not act for or on behalf of warrant holders. The following sets forth certain general terms and provisions of the warrants that may be offered under this registration statement, and is qualified in its entirety by reference to the relevant warrant agreement with respect to warrants of a particular series. Further terms of the warrants and the applicable warrant agreement will be set forth in the applicable prospectus supplement.

Debt Warrants

        The applicable prospectus supplement will describe the terms of the debt warrants in respect of which this prospectus is being delivered, including, where applicable, the following:

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        Debt warrant certificates will be exchangeable for new debt warrant certificates of different denominations and debt warrants may be exercised at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement. Prior to the exercise of their debt warrants, holders of debt warrants will not have any of the rights of holders of the securities purchasable upon such exercise, and will not be entitled to payments of principal, premium or interest on, the securities purchasable upon the exercise of debt warrants.

Equity Warrants

        The applicable prospectus supplement will describe the terms of the warrants to purchase common stock or preferred stock ("equity warrants"), in respect of which this prospectus is being delivered, including, where applicable, the following:

        Equity warrant certificates will be exchangeable for new equity warrant certificates of different denominations and warrants may be exercised at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement. Prior to the exercise of their equity warrants, holders of equity warrants will not have any of the rights of holders of the securities purchasable upon such exercise or to any dividend payments or voting rights as to which holders of the common stock or preferred stock purchasable upon such exercise may be entitled.

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        Except as provided in the applicable prospectus supplement, the exercise price and the number of shares of common stock or shares of preferred stock purchasable upon the exercise of each equity warrant will be subject to adjustment in certain events, including the issuance of a stock dividend to the holders of the underlying common stock or preferred stock or a stock split, reverse stock split, combination, subdivision or reclassification of the underlying common stock or preferred stock, as the case may be. In lieu of adjusting the number of shares purchasable upon exercise of each equity warrant, we may elect to adjust the number of equity warrants. Unless otherwise provided in the applicable prospectus supplement, no adjustments in the number of shares purchasable upon exercise of the equity warrants will be required until all cumulative adjustments require an adjustment of at least 1% thereof. We may, at our option, reduce the exercise price at any time. No fractional shares will be issued upon exercise of equity warrants, but we will pay the cash value of any fractional shares otherwise issuable.

        Notwithstanding the foregoing, except as otherwise provided in the applicable prospectus supplement, in case of any consolidation, merger or sale or conveyance of our property as an entirety or substantially as an entirety, the holder of each outstanding equity warrant will have the right to the kind and amount of shares of stock and other securities and property, including cash, receivable by a holder of the number of shares of common stock or shares of preferred stock into which each equity warrant was exercisable immediately prior to the particular triggering event.

Restrictions on Ownership and Transfer

        To assist us in complying with certain U.S. federal income tax requirements applicable to REITs, among other purposes, our charter contains certain restrictions relating to the ownership and transfer of our stock, including an ownership limit of 9.8% of our outstanding common stock and 9.8% in value of the outstanding shares of all classes or series of our stock, subject to certain exceptions. Our board may, from time to time, grant waivers from these restrictions, in its sole discretion. See "Restrictions on Ownership and Transfer" on page 24. We may choose to adopt similar restrictions with respect to any series or class of stock underlying the equity warrants offered pursuant to this prospectus under the articles supplementary or other charter document, as applicable, for each such class or series of stock. The applicable prospectus supplement will specify any additional ownership limitation relating to such equity warrants or class or series of stock underlying the equity warrants.

Exercise of Warrants

        Each warrant will entitle the holder to purchase for cash such number of debt securities, shares of common stock or shares of preferred stock, at such exercise price as shall, in each case, be set forth in, or be determinable as set forth in, the applicable prospectus supplement relating to the warrants offered thereby. Unless otherwise specified in the applicable prospectus supplement, warrants may be exercised at any time up to 5:00 p.m. New York City time on the expiration date set forth in applicable prospectus supplement. After 5:00 p.m. New York City time on the expiration date, unexercised warrants will be void.

        Warrants may be exercised as set forth in the applicable prospectus supplement relating to the warrants. Upon receipt of payment and the warrant certificate properly completed and duly executed at the corporate trust office of the warrant agent or any other office indicated in the applicable prospectus supplement, we will, as soon as practicable, forward the securities purchasable upon such exercise. If less than all of the warrants that are represented by such warrant certificate are exercised, a new warrant certificate will be issued for the remaining amount of warrants.

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DESCRIPTION OF RIGHTS

        We may issue rights to our stockholders to purchase debt securities, common stock, or preferred stock. Each series of rights will be issued under a separate rights agreement to be entered into between us and a bank or trust company, as rights agent, as specified in the applicable prospectus supplement. The rights agent will act solely as our agent in connection with the certificates relating to the rights of the series of certificates and will not assume any obligation or relationship of agency or trust for or with any holders of rights certificates or beneficial owners of rights. The following sets forth certain general terms and provisions of the rights that may be offered under this registration statement, and is qualified in its entirety by reference to the relevant rights agreement with respect to rights of a particular series. Further terms of the rights and the applicable rights agreement will be set forth in the applicable prospectus supplement. To the extent the information contained in the prospectus supplement differs from this summary description, you should rely on the information in the prospectus supplement.

        We will provide in a prospectus supplement the following terms of the rights being issued:

Restrictions on Ownership and Transfer

        To assist us in complying with certain U.S. federal income tax requirements applicable to REITs, among other purposes, our charter contains certain restrictions relating to the ownership and transfer of our stock, including an ownership limit of 9.8% of our outstanding common stock, subject to certain exceptions, which rights to purchase such shares of common stock are offered pursuant to this prospectus. Our board may, from time to time, grant waivers from these restrictions, in its sole discretion. See "Restrictions on Ownership and Transfer" on page 24. The applicable prospectus supplement will specify any additional ownership limitation relating to such rights.

Exercise of Rights

        Each right will entitle the holder of rights to purchase for cash the principal amount of debt securities, shares of common stock or shares of preferred stock at the exercise price provided in the applicable prospectus supplement. Rights may be exercised at any time up to the close of business on the expiration date for the rights provided in the applicable prospectus supplement. After the close of business on the expiration date, all unexercised rights will be void.

        Holders may exercise rights as described in the applicable prospectus supplement. Upon receipt of payment and the rights certificate properly completed and duly executed at the corporate trust office of the rights agent or any other office indicated in the prospectus supplement, we will, as soon as

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practicable, forward the debt securities, shares of common stock or shares of preferred stock purchasable upon exercise of the rights. If less than all of the rights issued in any rights offering are exercised, we may offer any unsubscribed securities directly to persons other than securityholders, to or through agents, underwriters or dealers or through a combination of such methods, including pursuant to standby underwriting arrangements, as described in the applicable prospectus supplement.

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DESCRIPTION OF UNITS

        We may issue units consisting of two or more other constituent securities. These units may be issuable as, and for a specified period of time may be transferable only as, a single security, rather than as the separate constituent securities comprising such units. The following sets forth certain general terms and provisions of the units that may be offered under this registration statement. Further terms of the units will be set forth in the applicable prospectus supplement. To the extent the information contained in the prospectus supplement differs from this summary description, you should rely on the information in the prospectus supplement.

        When we issue units, we will provide in a prospectus supplement the following terms of the units being issued:

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RESTRICTIONS ON OWNERSHIP AND TRANSFER

        The following summary with respect to restrictions on ownership and transfer of our stock (including warrants and rights to acquire our stock) sets forth certain general terms and provisions of our charter to which any prospectus supplement may relate. For purposes of this summary, references to "tenants" mean those persons who are referred to as "customers" elsewhere in this prospectus. This summary does not purport to be complete and is subject to and qualified in its entirety by reference to our charter, including any articles supplementary relating to any issuance of preferred stock pursuant to this prospectus. A copy of our charter has been filed with the SEC and is incorporated by reference as an exhibit to the registration statement of which this prospectus is a part. Any amendment or supplement to our charter relating to an issuance of securities pursuant to this prospectus shall be filed with the SEC and shall be filed or incorporated by reference as an exhibit to the applicable prospectus supplement. See "Where You Can Find More Information."

        In order for us to qualify as a REIT under the Code, shares of our stock must be owned by 100 or more persons during at least 335 days of a taxable year of 12 months (other than the first year for which an election to qualify as a REIT has been made) or during a proportionate part of a shorter taxable year. Also, not more than 50% of the value of the outstanding shares of our stock may be owned, directly or indirectly, by five or fewer individuals (as defined in the Code to include certain entities such as private foundations) during the last half of a taxable year (other than the first year for which an election to be a REIT has been made). To qualify as a REIT, we must satisfy other requirements as well. See "U.S. Federal Income Tax Considerations—Requirements for Qualification—General."

        Our charter contains restrictions on the ownership and transfer of our stock. Our board may, from time to time, grant waivers from these restrictions, in its sole discretion. The relevant sections of our charter provide that, subject to the exceptions described below, no person or entity may own, or be deemed to own, beneficially or by virtue of the applicable constructive ownership provisions of the Code, more than 9.8%, in value or in number of shares, whichever is more restrictive, of the outstanding shares of our common stock (the "common stock ownership limit") or 9.8% in value of the outstanding shares of all classes or series of our stock (the "aggregate stock ownership limit"). We refer to the common stock ownership limit and the aggregate stock ownership limit collectively as the "ownership limits." We refer to the person or entity that, but for operation of the ownership limits or another restriction on ownership and transfer of our stock as described below, would beneficially own or constructively own shares of our stock in violation of such limits or restrictions and, if appropriate in the context, a person or entity that would have been the record owner of such shares of our stock as a "prohibited owner."

        The constructive ownership rules under the Code are complex and may cause shares of stock owned beneficially or constructively by a group of related individuals and/or entities to be owned beneficially or constructively by one individual or entity. As a result, the acquisition of less than 9.8%, in value or in number of shares, whichever is more restrictive, of the outstanding shares of our common stock, or less than 9.8% in value of the outstanding shares of all classes and series of our stock (or the acquisition by an individual or entity of an interest in an entity that owns, beneficially or constructively, shares of our stock), could, nevertheless, cause that individual or entity, or another individual or entity, to own beneficially or constructively shares of our stock in excess of the ownership limits.

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        Our board of directors, in its sole discretion, may exempt, prospectively or retroactively, a particular stockholder from the ownership limits or establish a different limit on ownership (the "excepted holder limit") if our board of directors determines that:

        Any violation or attempted violation of any such representations or undertakings will result in such stockholder's shares of stock being automatically transferred to a charitable trust. As a condition of granting the waiver or establishing the excepted holder limit, our board of directors may require an opinion of counsel or a ruling from the IRS, in either case in form and substance satisfactory to our board of directors, in its sole discretion, in order to determine or ensure our status as a REIT and such representations and undertakings from the person requesting the exception as our board of directors may require in its sole discretion to make the determinations above. Our board of directors may impose such conditions or restrictions as it deems appropriate in connection with granting such a waiver or establishing an excepted holder limit. Our board of directors has granted CBI exemptions from the ownership limits applicable to other holders of our common stock, subject to certain initial and ongoing conditions designed to protect our status as a REIT, including the receipt of an IRS private letter ruling or an opinion of counsel from a nationally recognized law firm that the exercise of any such exemption should not cause any rent payable by CBI to jeopardize our REIT status. As of the date hereof, our board has granted limited waivers to several other holders.

        In connection with granting a waiver of the ownership limits or creating an excepted holder limit or at any other time, our board of directors may from time to time increase or decrease the common stock ownership limit, the aggregate stock ownership limit or both, for all other persons, unless, after giving effect to such increase, five or fewer individuals could beneficially own, in the aggregate, more than 49.9% in value of our outstanding stock or we would otherwise fail to qualify as a REIT. A reduced ownership limit will not apply to any person or entity whose percentage ownership of our common stock or our stock of all classes and series, as applicable, is, at the effective time of such reduction, in excess of such decreased ownership limit until such time as such person's or entity's percentage ownership of our common stock or our stock of all classes and series, as applicable, equals or falls below the decreased ownership limit, but any further acquisition of shares of our common stock or stock of all other classes or series, as applicable, will violate the decreased ownership limit.

        Our charter further prohibits:

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        Any person who acquires or attempts or intends to acquire beneficial or constructive ownership of shares of our stock that will or may violate the ownership limits or any of the other restrictions on ownership and transfer of our stock described above, or who would have owned shares of our stock transferred to the trust as described below, must immediately give notice to us of such event or, in the case of an attempted or proposed transaction, give us at least 15 days' prior written notice and provide us with such other information as we may request in order to determine the effect of such transfer on our status as a REIT.

        If any transfer of shares of our stock would result in shares of our stock being beneficially owned by fewer than 100 persons, the transfer will be null and void and the intended transferee will acquire no rights in the shares. In addition, if any purported transfer of shares of our stock or any other event would otherwise result in any person violating the ownership limits or an excepted holder limit established by our board of directors, or in our being "closely held" under Section 856(h) of the Code (without regard to whether the ownership interest is held during the last half of a taxable year) or otherwise failing to qualify as a REIT or as a "domestically controlled qualified investment entity" within the meaning of Section 897(h) of the Code, then that number of shares (rounded up to the nearest whole share) that would cause the violation will be automatically transferred to, and held by, a trust for the exclusive benefit of one or more charitable organizations selected by us, and the intended transferee or other prohibited owner will acquire no rights in the shares. The automatic transfer will be effective as of the close of business on the business day prior to the date of the violative transfer or other event that results in a transfer to the trust. If the transfer to the trust as described above is not automatically effective, for any reason, to prevent violation of the applicable ownership limits or our being "closely held" under Section 856(h) of the Code (without regard to whether the ownership interest is held during the last half of a taxable year) or our otherwise failing to qualify as a REIT or as a "domestically controlled qualified investment entity," then our charter provides that the transfer of the shares will be null and void and the intended transferee will acquire no rights in such shares.

        Shares of our stock held in the trust will be issued and outstanding shares. The prohibited owner will not benefit economically from ownership of any shares of our stock held in the trust and will have no rights to distributions and no rights to vote or other rights attributable to the shares of our stock held in the trust. The trustee of the trust will exercise all voting rights and receive all distributions with respect to shares held in the trust for the exclusive benefit of the charitable beneficiary of the trust. Any distribution made before we discover that the shares have been transferred to a trust as described above must be repaid by the recipient to the trustee upon demand by us. Subject to Maryland law, effective as of the date that the shares have been transferred to the trust, the trustee will have the authority to rescind as void any vote cast by a prohibited owner before our discovery that the shares have been transferred to the trust and to recast the vote in accordance with the desires of the trustee acting for the benefit of the charitable beneficiary of the trust. However, if we have already taken irreversible corporate action, then the trustee may not rescind and recast the vote.

        Shares of our stock transferred to the trustee are deemed offered for sale to us, or our designee, at a price per share equal to the lesser of (i) the price paid by the prohibited owner for the shares (or, in the case of a devise or gift, the market price at the time of such devise or gift) and (ii) the market price on the date we accept, or our designee, accepts such offer. We may reduce the amount so payable to the trustee by the amount of any distribution that we made to the prohibited owner before we discovered that the shares had been automatically transferred to the trust and that are then owed by the prohibited owner to the trustee as described above, and we may pay the amount of any such reduction to the trustee for distribution to the charitable beneficiary. We have the right to accept such offer until the trustee has sold the shares of our stock held in the trust as discussed below. Upon a sale to us, the interest of the charitable beneficiary in the shares sold terminates, and the trustee must distribute the net proceeds of the sale to the prohibited owner and must distribute any distributions held by the trustee with respect to such shares to the charitable beneficiary.

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        If we do not buy the shares, the trustee must, within 20 days of receiving notice from us of the transfer of shares to the trust, sell the shares to a person or entity designated by the trustee who could own the shares without violating the ownership limits or the other restrictions on ownership and transfer of our stock. After the sale of the shares, the interest of the charitable beneficiary in the shares transferred to the trust will terminate and the trustee must distribute to the prohibited owner an amount equal to the lesser of (i) the price paid by the prohibited owner for the shares (or, if the prohibited owner did not give value for the shares in connection with the event causing the shares to be held in the trust (for example, in the case of a gift, devise or other such transaction), the market price of the shares on the day of the event causing the shares to be held in the trust) and (ii) the sales proceeds (net of any commissions and other expenses of sale) received by the trust for the shares. The trustee may reduce the amount payable to the prohibited owner by the amount of any distribution that we paid to the prohibited owner before we discovered that the shares had been automatically transferred to the trust and that are then owed by the prohibited owner to the trustee as described above. Any net sales proceeds in excess of the amount payable to the prohibited owner must be paid immediately to the charitable beneficiary, together with any distributions thereon. In addition, if, prior to the discovery by us that shares of stock have been transferred to a trust, such shares of stock are sold by a prohibited owner, then such shares will be deemed to have been sold on behalf of the trust and, to the extent that the prohibited owner received an amount for or in respect of such shares that exceeds the amount that such prohibited owner was entitled to receive, such excess amount will be paid to the trustee upon demand. The prohibited owner has no rights in the shares held by the trustee.

        In addition, if our board of directors determines in good faith that a transfer or other event has occurred that would violate the restrictions on ownership and transfer of our stock described above, our board of directors may take such action as it deems advisable to refuse to give effect to or to prevent such transfer, including, but not limited to, causing us to redeem shares of our stock, refusing to give effect to the transfer on our books or instituting proceedings to enjoin the transfer.

        Every owner of 5% or more (or such lower percentage as required by the Code or the regulations promulgated thereunder) of our stock, within 30 days after the end of each taxable year, must give us written notice stating the stockholder's name and address, the number of shares of each class and series of our stock that the stockholder beneficially owns and a description of the manner in which the shares are held. Each such owner must provide to us in writing such additional information as we may request in order to determine the effect, if any, of the stockholder's beneficial ownership on our status as a REIT and to ensure compliance with the ownership limits. In addition, any person or entity that is a beneficial owner or constructive owner of shares of our stock and any person or entity (including the stockholder of record) who is holding shares of our stock for a beneficial owner or constructive owner must, on request, provide to us such information as we may request in good faith in order to determine our status as a REIT and to comply with the requirements of any taxing authority or governmental authority or to determine such compliance and to ensure compliance with the ownership limits.

        Any certificates representing shares of our stock will bear a legend referring to the restrictions on ownership and transfer of our stock described above.

        These restrictions on ownership and transfer of our stock will not apply if our board of directors determines that it is no longer in our best interests to attempt to qualify, or to continue to qualify, as a REIT or that compliance is no longer required.

        The restrictions on ownership and transfer of our stock described above could delay, defer or prevent a transaction or a change in control that might involve a premium price for our common stock or otherwise be in the best interests of our stockholders.

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DESCRIPTION OF THE PARTNERSHIP AGREEMENT OF CYRUSONE LP

        We have summarized the material terms and provisions of the Amended and Restated Agreement of Limited Partnership of CyrusOne LP, which we refer to as the "partnership agreement." This summary is not complete. For more detail, you should refer to the partnership agreement itself, a copy of which has been filed with the SEC and is incorporated by reference as an exhibit to the registration statement of which this prospectus is a part. For purposes of this section, references to "we," "our," "us" and "our company" refer to CyrusOne Inc.

Management of Our Operating Partnership

        Our operating partnership, CyrusOne LP, is a Maryland limited partnership that was formed on July 31, 2012. CyrusOne GP, our wholly-owned subsidiary, is the sole general partner of our operating partnership, a