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    <Log type="Info">Columns in Cash Flows statement 'Condensed Consolidated Statements of Cash Flows (USD $)' have maximum duration 365 days and at least 103 values. Shorter duration columns must have at least one fourth (25) as many values. Column '10/1/2012 - 12/31/2012' is shorter (91 days) and has only 4 values, so it is being removed.</Log>
    <Log type="Info">Columns in Cash Flows statement 'Condensed Consolidated Statements of Cash Flows (USD $)' have maximum duration 365 days and at least 103 values. Shorter duration columns must have at least one fourth (25) as many values. Column '1/1/2013 - 3/31/2013' is shorter (89 days) and has only 4 values, so it is being removed.</Log>
    <Log type="Info">Columns in Cash Flows statement 'Condensed Consolidated Statements of Cash Flows (USD $)' have maximum duration 365 days and at least 103 values. Shorter duration columns must have at least one fourth (25) as many values. Column '4/1/2013 - 6/30/2013' is shorter (90 days) and has only 6 values, so it is being removed.</Log>
    <Log type="Info">Columns in Cash Flows statement 'Condensed Consolidated Statements of Cash Flows (USD $)' have maximum duration 365 days and at least 103 values. Shorter duration columns must have at least one fourth (25) as many values. Column '7/1/2013 - 9/30/2013' is shorter (91 days) and has only 5 values, so it is being removed.</Log>
    <Log type="Info">Columns in Cash Flows statement 'Condensed Consolidated Statements of Cash Flows (USD $)' have maximum duration 365 days and at least 103 values. Shorter duration columns must have at least one fourth (25) as many values. Column '10/1/2013 - 12/31/2013' is shorter (91 days) and has only 7 values, so it is being removed.</Log>
    <Log type="Info">Columns in Cash Flows statement 'Condensed Consolidated Statements of Cash Flows (USD $)' have maximum duration 365 days and at least 103 values. Shorter duration columns must have at least one fourth (25) as many values. Column '1/1/2014 - 3/31/2014' is shorter (89 days) and has only 4 values, so it is being removed.</Log>
    <Log type="Info">Columns in Cash Flows statement 'Condensed Consolidated Statements of Cash Flows (USD $)' have maximum duration 365 days and at least 103 values. Shorter duration columns must have at least one fourth (25) as many values. Column '4/1/2014 - 6/30/2014' is shorter (90 days) and has only 4 values, so it is being removed.</Log>
    <Log type="Info">Columns in Cash Flows statement 'Condensed Consolidated Statements of Cash Flows (USD $)' have maximum duration 365 days and at least 103 values. Shorter duration columns must have at least one fourth (25) as many values. Column '10/1/2014 - 12/31/2014' is shorter (91 days) and has only 6 values, so it is being removed.</Log>
    <Log type="Info">Columns in Cash Flows statement 'Condensed Consolidated Statements of Cash Flows (USD $)' have maximum duration 365 days and at least 103 values. Shorter duration columns must have at least one fourth (25) as many values. Column '7/1/2012 - 7/31/2012' is shorter (30 days) and has only 3 values, so it is being removed.</Log>
    <Log type="Info">'Monetary' elements on report '144 - Disclosure - Business,Basis of Presentation and Significant Accounting Policies - Additional Information (Detail)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '147 - Disclosure - Acquisitions - (Narrative) (Detail)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '163 - Disclosure - Long-Term Debt (Narrative) (Detail)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '174 - Disclosure - Equity (Narrative) (Detail)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '176 - Disclosure - Stock-Based Compensation (Narrative) (Detail)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '181 - Disclosure - Fair Value Measurements (Schedule Of Financial Instruments Measured At Fair Value On A Recurring Basis) (Detail)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">'Monetary' elements on report '194 - Disclosure - Subsequent Events (Detail)' had a mix of different decimal attribute values.</Log>
    <Log type="Info">Process Flow-Through: 103 - Statement - Condensed Consolidated Balance Sheets</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Dec. 31, 2013'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Jun. 30, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Jun. 30, 2011'</Log>
    <Log type="Info">Process Flow-Through: 104 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)</Log>
    <Log type="Info">	Process Flow-Through: Removing column 'Oct. 10, 2014'</Log>
    <Log type="Info">Process Flow-Through: 105 - Statement - Condensed Consolidated Statements Of Operations</Log>
    <Log type="Info">	Process Flow-Through: Removing column '1 Months Ended
Jul. 31, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2014'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2014'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2013'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2013'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2013'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '12 Months Ended
Jun. 13, 2014'</Log>
    <Log type="Info">Process Flow-Through: 106 - Statement - Condensed Consolidated Statements Of Comprehensive Loss</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2014'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2014'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2013'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Jun. 30, 2013'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Mar. 31, 2013'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Dec. 31, 2012'</Log>
    <Log type="Info">	Process Flow-Through: Removing column '3 Months Ended
Sep. 30, 2012'</Log>
    <Log type="Info">Process Flow-Through: 108 - Statement - Condensed Consolidated Statements of Cash Flows</Log>
    <Log type="Info">	Process Flow-Through: Removing column '12 Months Ended
Jun. 13, 2014'</Log>
  </Logs>
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    <File>zayo-20141231.xml</File>
    <File>zayo-20141231.xsd</File>
    <File>zayo-20141231_cal.xml</File>
    <File>zayo-20141231_def.xml</File>
    <File>zayo-20141231_lab.xml</File>
    <File>zayo-20141231_pre.xml</File>
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