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                                                                  Exhibit 10.12

                                                    [Verizon Logo]

                                                    VERIZON COMMUNICATIONS INC.
                                                    1095 Avenue of the Americas
November 12, 2002                                      New York, New York 10036


Genuity Inc.
225 Presidential Way
Woburn, MA 01801

JP Morgan Chase Bank,
as Agent, and
each of the Lenders,
as defined herein

                           FIFTH STANDSTILL AGREEMENT

       Reference is made to: (i) the Credit Agreement, dated as of March 5, 2001
(as amended from time to time, the "Credit Agreement"), by and between Verizon
Investments Inc., a Delaware corporation ("Verizon Investments") and Genuity
Inc., a Delaware corporation ("Genuity"); (ii) the $2,000,000,000 Amended and
Restated Credit Agreement , dated as of September 24, 2001 (as amended from time
to time, the "Revolving Credit Agreement"), among Genuity, JP Morgan Chase Bank,
as agent (the "Agent"), the lenders party thereto (the "Lenders") and the other
parties party thereto; and (iii) Standstill Agreement No. 6, dated as of
November 12, 2002 (as in effect on the date hereof, "Standstill Agreement No.
6"), between Genuity and the Lenders party thereto. Capitalized terms not
otherwise defined herein shall have the meanings specified therefor in the
Credit Agreement.

       Verizon Investments and Genuity recognize that certain Events of Default
have occurred and are continuing (a) under the Credit Agreement as a result of
the conversion by affiliates of Verizon Investments of Class B common shares of
Genuity into Class A Shares and (b) attributable to events relating to
insolvency or similar proceedings of (including, without limitation, the
financial condition, payment of taxes by, or solvency of) Integra S.A., a 93%
owned subsidiary of Genuity organized under the laws of France (collectively,
the "Existing Defaults").

       Verizon Investments and Verizon Communications Inc., a Delaware
corporation ("VCI" and, together with Verizon Investments, "Verizon"), hereby
agree and acknowledge to and for the benefit of each of Genuity, the Agent and
the Lenders the following:

       During the period (the "Verizon Standstill Period") commencing on July
29, 2002 and ending on November 22, 2002, or such earlier date on which the
Standstill Period (as contemplated by, and as defined in, Standstill Agreement
No. 6) terminates or is rescinded (in any such event, the "Termination Date"),
Verizon agrees (i) with respect

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to the Existing Defaults, that it will not exercise any of its rights or
remedies under or with respect to the Credit Agreement, including, without
limitation, any right to declare any or all amounts payable under the Credit
Agreement to be immediately due and payable, and (ii) that it will not commence
or cause to be commenced or file any suit, proceeding or litigation in any
court, governmental agency or arbitrator against or directly affecting Genuity
in any way relating to the Credit Agreement.

       On the Termination Date, without any further action by Verizon, all of
the terms and provisions set forth in the Credit Agreement with respect to the
Existing Defaults shall have the same force and effect as if this Agreement had
not been entered into by the parties hereto, and Verizon shall have all of the
rights and remedies afforded to it under the Credit Agreement and applicable law
with respect to the Existing Defaults as though no standstill had been granted
by it hereunder. Except as expressly set forth herein, nothing in this Agreement
shall affect the rights and remedies of Verizon under or in connection with the
Credit Agreement with respect to any Event of Default, other than the Existing
Defaults, or any other event or occurrence.

       During the Verizon Standstill Period, Verizon agrees not to take any
action described in Section 3(d) of Standstill Agreement No. 6.

       Nothing herein shall be interpreted as requiring Verizon to make any
additional advances under the Credit Agreement.


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       This Agreement shall be effective immediately upon the execution hereof
as of the date hereof.

                                        VERIZON COMMUNICATIONS INC.

                                        By    /s/ WILLIAM F. HEITMANN
                                          -------------------------------------
                                        Title: Senior Vice President and
                                               Treasurer

                                        VERIZON INVESTMENTS INC.

                                        By    /s/ WILLIAM F. HEITMANN
                                          -------------------------------------
                                        Title: Vice President and Secretary


Accepted and agreed to

GENUITY INC.


By     /s/ PAUL R. GUDONIS
  -----------------------------------------
Title: Chairman and Chief Executive Officer