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                                                                EXHIBIT 10.26.12


                        FIRST AMENDMENT, dated as of January 27, 2000 (this
                "Amendment"), to the Parent Agreement ( the "Parent Agreement"),
                dated as of September 17, 1999, between Leap Wireless
                International, Inc. (the "Parent") and Lucent Technologies,
                Inc., as Administrative Agent for the Lenders, as defined in the
                Parent Agreement (the Administrative Agent").


        WHEREAS, Parent has requested that certain provisions of the Parent
Agreement be amended in certain respects, and Administrative Agent is willing to
amend such provisions on the terms and subject to the conditions set forth
herein;

        NOW THEREFORE, for and in consideration of the mutual agreements
contained in this Amendment and other good and valuable consideration, the
sufficiency and receipt of which are hereby acknowledged, the parties hereto
hereby agree as follows:

        SECTION 1. Amendments. Section 9(c) of the Parent Agreement is amended
and restated in its entirety to read as follows:

                "(c) Upon the payment of all amounts outstanding under the
        QUALCOMM Credit Agreement and the termination of all commitments to lend
        under the QUALCOMM Credit Agreement, the Parent shall comply with the
        covenants set forth in Section 5 of the QUALCOMM Credit Agreement as in
        effect as of the Effective Date, without giving effect to any subsequent
        amendment or waiver thereto; provided, however:

                        (i) for purposes of this Section 9(c), the term
                "Permitted Liens" as used in the QUALCOMM Credit Agreement,
                shall be deemed to include liens on any collateral account
                funded by the Parent from the net proceeds of the issuance of
                Eligible Parent Debt in an amount sufficient to pay cash
                interest on such Eligible Parent Debt;

                        (ii) Section 5.1(h) of the QUALCOMM Credit Agreement
                shall be deemed to read:

                                `(h) Consents and Approvals. From time to time
                        obtain all material necessary governmental and third
                        party consents, approvals and licenses in connection
                        with the transactions contemplated by the Specified
                        Agreements.'; and

                        (iii) Section 5.1(j) shall be deemed to have been
                deleted from the QUALCOMM Credit Agreement.


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                As used in this Section 9(c), the term "Eligible Parent Debt"
                shall have the meaning ascribed to such term in the Credit
                Agreement, dated as of September 20, 1999 and as amended through
                the date hereof, among Cricket Communications Holdings, Inc.,
                Cricket Communications, Inc., the lenders party thereto and
                Lucent Technologies, Inc."

        SECTION 2. Consent to Amendment. Notwithstanding the provisions of
Section 10(a) of the Parent Agreement, Administrative Agent agrees that if
Parent fails to raise high-yield debt but is successful in raising equity, then
Parent may amend Section 5.3 of the QUALCOMM Credit Agreement to require a Total
Debt to Total Capitalization ratio of 70% for periods prior to the fourth
anniversary of the closing date of such credit agreement

        SECTION 3. Applicable Law. THIS AMENDMENT SHALL BE CONSTRUED IN
ACCORDANCE WITH AND GOVERNED BY THE LAWS OF THE STATE OF NEW YORK.

        SECTION 4. Expenses. The Borrower agrees to reimburse the Administrative
Agent for its out-of-pocket expenses in connection with this Amendment,
including the fees, charges and disbursements of Cravath, Swaine & Moore,
counsel for the Administrative Agent.

        SECTION 5. Counterparts. This Amendment may be executed in two or more
counterparts, each of which shall constitute an original but all of which when
taken together shall constitute but one contract. Delivery of an executed
counterpart of a signature page by


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facsimile transmission shall be effective as delivery of a manually executed
counterpart of this Amendment.

        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed by the respective authorized officers as of the day and year first
written above.



                                           Leap Wireless International, Inc.

                                           By: /s/ James E. Hoffmann
                                              ----------------------------------
                                              Name: James E. Hoffmann
                                              Title: Sr. Vice President



                                           LUCENT TECHNOLOGIES, INC., as
                                           Administrative Agent

                                           By: /s/ Dina Fede
                                              ----------------------------------
                                              Name: Dina Fede
                                              Title: Director - Customer Finance