Exhibit 4.1





Exhibit 4.1




FOURTH SUPPLEMENTAL INDENTURE




THIS FOURTH SUPPLEMENTAL INDENTURE (the “Supplemental Indenture”) is dated as of
December 1, 2011, by and among Zayo Group, LLC, a Delaware limited liability company (the
“Company”), and Zayo Capital, Inc., a Delaware corporation (the “Co-Issuer” and,
together with the Company, the “Issuers”), the Guarantors named on the signature pages
hereto, and The Bank of New York Mellon Trust Company, N.A., a national banking association
organized and existing under the laws of the United States of America, as trustee (the
“Trustee”).



WITNESSETH:




WHEREAS, the Issuers, the Guarantors (as defined in the Indenture referred to below) and the
Trustee have executed and delivered an indenture, dated as of March 12, 2010 (the “Base
Indenture”), as supplemented by the First Supplemental Indenture, dated as of September 13,
2010 (the “First Supplemental Indenture”), between Zayo Fiber Solutions, LLC, and the
Trustee, the Second Supplemental Indenture, dated as of September 20, 2010 (the “Second
Supplemental Indenture”), among the Issuers, the Guarantors party thereto and the Trustee, and
the Third Supplemental Indenture, dated as of November 5, 2010 (the “Third Supplemental
Indenture”), among American Fiber Systems Holding Corporation, American Fiber Systems, Inc. and
the Trustee (such Base Indenture, as supplemented by the First Supplemental Indenture, the Second
Supplemental Indenture and the Third Supplemental Indenture, the “Indenture”);



WHEREAS, the Indenture provides for the issuance of an unlimited aggregate principal amount of
10.25% Senior Secured First-Priority Notes due 2017 (the “Notes”); and



WHEREAS, pursuant to and in accordance with Section 9.01(4) of the Indenture, the Issuers, the
Guarantors and the Trustee are authorized to execute and deliver this Supplemental Indenture
without the consent of any Holder;



NOW, THEREFORE, in consideration of the foregoing and for other good and valuable
consideration, the receipt of which is hereby acknowledged, the parties mutually covenant and agree
as follows:



ARTICLE I




AMENDMENTS





Section 1.1 Amendment to Section 1.01.



The definition of “Permitted Additional Pari Passu Obligations” is hereby replaced in its
entirety with the following:



“Permitted Additional Pari Passu Obligations” means any obligation under any
Additional Notes or any other indebtedness (whether or not consisting of Additional Notes) not more
than equally and ratably secured on a first-lien basis with the Notes by Liens on the Collateral
(it being understood, for the avoidance of doubt, that Permitted Additional Pari Passu
Obligations may be secured on a first-lien basis with the Notes by Liens on less than all of
the Collateral); provided that, as of the date of Incurrence of such Permitted Additional
Pari Passu Obligations, after giving effect thereto and the application of proceeds therefrom, the
Consolidated Secured Debt Ratio of the Company and its Restricted Subsidiaries would be no greater
than 3.5 to 1.0.


 


 









 





ARTICLE II




MISCELLANEOUS





Section 2.1 Effect of this Supplemental Indenture.



This Supplemental Indenture supplements the Indenture and shall be a part, and subject to all
the terms, thereof. The Indenture, as supplemented by this Supplemental Indenture, is in all
respects ratified and confirmed, and the Indenture and this Supplemental Indenture shall be read,
taken and construed as one and the same instrument. The Trustee accepts the trusts created by the
Indenture, as supplemented by this Supplemental Indenture, and agrees to perform the same upon the
terms and conditions of the Indenture, as supplemented by this Supplemental Indenture.




Section 2.2 Capitalized Terms. 



Capitalized terms used herein without definition shall have the meanings assigned to them in
the Indenture.




Section 2.3 Governing Law.



THIS SUPPLEMENTAL INDENTURE WILL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF
THE STATE OF NEW YORK.




Section 2.4 Counterparts.



The parties may sign any number of copies of this Supplemental Indenture. Each signed copy
shall be an original, but all of them together represent the same agreement.




Section 2.5 Effect of Headings.



The Section headings herein are for convenience only and shall not affect the construction
hereof.




Section 2.6 The Trustee. 



The Trustee shall not be responsible in any manner whatsoever for or in respect of the
validity of sufficiency of this Supplemental Indenture or for or in respect of the recitals
contained herein, all of which recitals are made solely by the Issuers and Guarantors.




Section 2.7 Benefits Acknowledged.



Each Guarantor’s Guarantee is subject to the terms and conditions set forth in the Indenture.
Each Guarantor acknowledges that it will receive direct and indirect benefits from the
financing arrangements contemplated by the Indenture and this Supplemental Indenture and that
the guarantee and waivers made by it pursuant to this Note Guarantee are knowingly made in
contemplation of such benefits.


 


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Section 2.8 Successors and Assigns.



All agreements of the Issuers and the Guarantors in this Supplemental Indenture shall bind
their respective successors, except as otherwise provided in the Indenture. All agreements of the
Trustee in this Supplemental Indenture shall bind its successors.




Section 2.9 Severability.



If any provision of this Supplemental Indenture is held to be invalid, illegal or
unenforceable, such invalidity, illegality or unenforceability shall not affect any other provision
and this Supplemental Indenture shall be reformed, construed and enforced as if such invalid,
illegal or unenforceable provision had never been contained herein.



[Signature pages follow]



 


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IN WITNESS WHEREOF, the parties hereto have caused this Supplemental Indenture to be duly
executed all as of the day and year first above written.



	 	 	 	 	 
	THE ISSUERS:	 	 
	 
	 	 	 	 
	ZAYO GROUP, LLC	 	 
	 
	 	 	 	 
	By:

	 	/s/ Ken desGarennes	 	 
	 

	 	 

Name: Ken desGarennes

Title:   Chief Financial Officer
	 	 
	 
	 	 	 	 
	ZAYO CAPITAL, INC.	 	 
	 
	 	 	 	 
	By:

	 	/s/ Ken desGarennes	 	 
	 

	 	 

Name: Ken desGarennes

Title:   Chief Financial Officer
	 	 






Fourth Supplemental Indenture




 


 









 







	 	 	 	 	 
	THE GUARANTORS:

ZAYO COLOCATION, INC.

AMERICAN FIBER SYSTEMS, INC.

AMERICAN FIBER SYSTEMS HOLDING CORP.

FIBERNET TELECOM, INC.

LOCAL FIBER, LLC	 	 
	 
	 	 	 	 
	By:

	 	/s/ Ken desGarennes	 	 
	 

	 	 

Name: Ken desGarennes

Title:   Chief Financial Officer
	 	 






Fourth Supplemental Indenture



 


 









 







	 	 	 	 	 
	THE TRUSTEE:	 	 
	 
	 	 	 	 
	The Bank of New York Mellon Trust Company, N.A., as Trustee	 	 
	 
	 	 	 	 
	By:

	 	/s/ Raymond Torres	 	 
	 

	 	 

Name: Raymond Torres
	 	 
	 

	 	Title:   Senior Associate	 	 






Fourth Supplemental Indenture