Exhibit 10.6

EXECUTION COPY

SUPPLEMENT NO. 1 dated as of March 13, 2007 to the Omnibus Offering Proceeds
Note Subordination Agreement dated as of March 13, 2007 (the “Omnibus Offering
Proceeds Note Subordination Agreement”), among LEVEL 3 COMMUNICATIONS, INC.
(“Level 3”), LEVEL 3 COMMUNICATIONS, LLC (“Level 3 LLC”), LEVEL 3 FINANCING,
INC. (the “Borrower”), each Subsidiary of Level 3 becoming a party thereto
pursuant to Section 4.12 thereof (each such Subsidiary and Level 3 LLC, a
“Intercompany Obligor”), and each Subsidiary of Level 3 becoming a party thereto
pursuant to Section 4.13 thereof (each such Subsidiary, Level 3 and the
Borrower, a “Subordinated Lender”).

Reference is made to the Omnibus Offering Proceeds Note Subordination Agreement.

Capitalized terms used and not otherwise defined herein shall have the meanings
assigned to such terms in the Omnibus Offering Proceeds Note Subordination
Agreement.

Section 4.12 of the Omnibus Offering Proceeds Note Subordination Agreement
provides that a Subsidiary of Level 3 may become an Intercompany Obligor under
the Omnibus Offering Proceeds Note Subordination Agreement by execution and
delivery of an instrument in the form of this Supplement. The undersigned
Subsidiary of Level 3 (the “New Intercompany Obligor”) is executing this
Supplement to become an Intercompany Obligor under the Omnibus Offering Proceeds
Note Subordination Agreement in order to comply with the terms of the Credit
Agreement and as consideration for amounts previously advanced to the Borrower
under the Credit Agreement.

Accordingly, the New Intercompany Obligor agrees as follows:

In accordance with Section 4.12 of the Omnibus Offering Proceeds Note
Subordination Agreement, the New Intercompany Obligor by its signature below
becomes an Intercompany Obligor under the Omnibus Offering Proceeds Note
Subordination Agreement with the same force and effect as if originally named
therein as an Intercompany Obligor and the New Intercompany Obligor hereby
agrees to all the terms and provisions of the Omnibus Offering Proceeds Note
Subordination Agreement applicable to it as an Intercompany Obligor thereunder.
Each reference to an “Intercompany Obligor” in the Omnibus Offering Proceeds
Note Subordination Agreement shall be deemed to include the New Intercompany
Obligor. The Omnibus Offering Proceeds Note Subordination Agreement is hereby
incorporated herein by reference.

The New Intercompany Obligor represents and warrants to the Borrower that this
Supplement has been duly authorized, executed and delivered by it and
constitutes its legal, valid and binding obligation, enforceable against it in
accordance with its terms, subject to applicable bankruptcy, insolvency,
moratorium or other laws affecting creditors’ rights generally and subject to
general principles of equity regardless of whether considered in a proceeding in
equity or at law.

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This Supplement may be executed in counterparts, each of which shall constitute
an original, but all of which, when taken together, shall constitute a single
contract. This Supplement shall become effective when the Borrower shall have
received counterparts of this Supplement that, when taken together, bear the
signatures of the New Intercompany Obligor and the Borrower. Delivery of an
executed signature page to this Supplement by facsimile transmission shall be as
effective as delivery of a manually executed counterpart of this Supplement.

Except as expressly supplemented hereby and pursuant to any other supplement
contemplated by Section 4.12 or 4.13 of the Omnibus Offering Proceeds Note
Subordination Agreement, the Omnibus Offering Proceeds Note Subordination
Agreement shall remain in full force and effect.

THIS SUPPLEMENT SHALL BE GOVERNED BY, AND CONSTRUED IN ACCORDANCE WITH, THE LAWS
OF THE STATE OF NEW YORK BUT WITHOUT GIVING EFFECT TO APPLICABLE PRINCIPLES OF
CONFLICTS OF LAW TO THE EXTENT THAT THE APPLICATION OF THE LAWS OF ANOTHER
JURISDICTION WOULD BE REQUIRED THEREBY.

In the event any one or more of the provisions contained in this Supplement
should be held invalid, illegal or unenforceable in any respect, the validity,
legality and enforceability of the remaining provisions contained herein shall
not in any way be affected or impaired thereby. The parties shall endeavor in
good faith negotiations to replace any invalid, illegal or unenforceable
provisions with valid provisions the economic effect of which comes as close as
possible to that of the invalid, illegal or unenforceable provisions.

All communications and notices hereunder shall be in writing and given as
provided in Section 4.1 of the Omnibus Offering Proceeds Note Subordination
Agreement. All communications and notices hereunder to the New Intercompany
Obligor shall be given to it in care of the Borrower.

[remainder of page intentionally blank; signature page is the next page]

 

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IN WITNESS WHEREOF, the New Intercompany Obligor and the Borrower have duly
executed this Supplement to the Omnibus Offering Proceeds Note Subordination
Agreement as of the day and year first above written.

 

BROADWING FINANCIAL SERVICES, INC., By   /s/ Neil J. Eckstein       Name: Neil
J. Eckstein   Title:    Assistant Secretary

 

LEVEL 3 FINANCING, INC., By   /s/ Neil J. Eckstein       Name: Neil J. Eckstein
  Title:    Assistant Secretary

 

 

 

 

 

 

 

 

 

[SIGNATURE PAGE TO BROADWING SUPPLEMENT TO OMNIBUS OFFERING PROCEEDS NOTE
SUBORDINATION AGREEMENT]

 

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