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                                                                   EXHIBIT 4.6.1



                       FIRST AMENDMENT TO RIGHTS AGREEMENT


               FIRST AMENDMENT, dated as of February 8, 2000 ("First
Amendment"), to Rights Agreement dated as of September 14, 1998 (the "Rights
Agreement"), between Leap Wireless International, Inc., a Delaware corporation
(the "Company"), and Harris Trust Company of California (the "Rights Agent").
Capitalized terms used but not otherwise defined herein shall have the meanings
ascribed to them in the Rights Agreement.

               WHEREAS, the Company and the Rights Agent previously entered into
the Rights Agreement; and

               WHEREAS, pursuant to Section 26 of the Rights Agreement, the
Company and the Rights Agent may from time to time supplement or amend any
provision of the Rights Agreement in accordance with the terms of such Section
26.

               NOW, THEREFORE, in consideration of the foregoing promises and
mutual agreements set forth in this Amendment, the parties hereby amend the
Rights Agreement as follows:

               1. Section 1.1 of the Rights Agreement is hereby amended and
restated in its entirety as follows:

        ""Acquiring Person" shall mean any Person (as such term is hereinafter
        defined) who or which, together with all Affiliates and Associates (as
        such terms are hereinafter defined) of such Person, shall be the
        Beneficial Owner (as such term is hereinafter defined) of 15% or more of
        the Common Shares of the Company then outstanding but shall not include
        (i) an Exempt Person or (ii) any Existing Holder, unless and until such
        time as such Existing Holder shall become the Beneficial Owner of one or
        more additional Common Shares of the Company (other than pursuant to a
        dividend or distribution paid or made by the Company on the outstanding
        Common Shares in Common Shares or pursuant to a split or subdivision of
        the outstanding Common Shares), unless, upon becoming the Beneficial
        Owner of such additional Common Shares, such Existing Holder is not then
        the Beneficial Owner of 15% or more of the Common Shares then
        outstanding. "Existing Holder" shall mean QUALCOMM Incorporated,
        together with all of its Affiliates and Associates (but excluding the
        beneficial ownership of individual officers, directors and employees of
        QUALCOMM Incorporated, solely by reason of such persons' status or
        authority as such), and, for purposes of this Rights Agreement, (x)
        prior to the consummation of the proposed "spin-off" distribution of
        Common Shares to the common stockholders of QUALCOMM Incorporated (the
        "Spin-Off"), QUALCOMM Incorporated may acquire one or more additional
        Common Shares without becoming an Acquiring Person hereunder, and (y)
        from and after the consummation of the Spin-Off, (1) QUALCOMM
        Incorporated may become the Beneficial Owner of up to 4,500,000 Common
        Shares (subject to adjustment), provided such beneficial ownership of
        Common Shares is acquired solely upon the issuance by the Company to
        QUALCOMM

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        Incorporated of that certain Warrant to purchase 4,500,000 Common Shares
        (subject to adjustment) following the consummation of the Spin-Off or
        upon the exercise of such Warrant in accordance with its terms, and (2)
        QUALCOMM Incorporated may become the Beneficial Owner of up to 775,000
        Common Shares (subject to adjustment), provided such beneficial
        ownership of Common Shares is acquired solely upon the issuance by the
        Company to QUALCOMM Incorporated of Warrants acquired through the
        purchase of those certain Units, each such Unit consisting of one [note]
        and one Warrant to purchase Common Shares, such Warrants in the
        aggregate entitling QUALCOMM Incorporated to purchase up to 775,000
        Common Shares (subject to adjustment) or upon the exercise of such
        Warrants in accordance with their terms, without becoming an Acquiring
        Person hereunder. Notwithstanding the foregoing, no Person shall become
        an "Acquiring Person" as the result of an acquisition of Common Shares
        by the Company which, by reducing the number of shares outstanding,
        increases the proportionate number of shares beneficially owned by such
        Person to 15% or more of the Common Shares of the Company then
        outstanding; PROVIDED, HOWEVER, that if a Person shall become the
        Beneficial Owner of 15% or more of the Common Shares of the Company then
        outstanding solely by reason of share purchases by the Company and
        shall, after notice from or public disclosure by the Company of such
        share purchases by the Company, become the Beneficial Owner of one or
        more additional Common Shares of the Company, then such Person shall be
        deemed to be an "Acquiring Person." Notwithstanding the foregoing, if
        the Board of Directors of the Company determines in good faith that a
        Person who would otherwise be an "Acquiring Person," as defined pursuant
        to the foregoing provisions of this Section 1.1, has become such
        inadvertently (including, without limitation, because (A) such Person
        was unaware that it beneficially owned a percentage of Common Stock that
        would otherwise cause such Person to be an "Acquiring Person" or (B)
        such Person was aware of the extent of its Beneficial Ownership of
        Common Stock but had no actual knowledge of the consequences of such
        Beneficial Ownership under this Agreement), and without any intention of
        changing or influencing control of the Company, and such Person divests
        as promptly as practicable a sufficient number of Common Shares so that
        such Person would no longer be an Acquiring Person, as defined pursuant
        to the foregoing provisions of this Section 1.1, then such Person shall
        not be deemed to be or have become an "Acquiring Person" at any time for
        any purposes of this Agreement. For all purposes of this Agreement, any
        calculation of the number of Common Shares outstanding at any particular
        time, including for purposes of determining the particular percentage of
        such outstanding Common Shares of which any Person is the Beneficial
        Owner, shall be made in accordance with the last sentence of Rule
        13d-3(d)(1)(i) of the General Rules and Regulations under the Securities
        Exchange Act of 1934, as amended (the "Exchange Act"), as in effect on
        the date of this Agreement."



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               IN WITNESS WHEREOF, the parties have executed this First
Amendment as of the date first written above.


        LEAP WIRELESS INTERNATIONAL, INC.


        By:  /s/ James E. Hoffmann
             --------------------------------
        Name:  James E. Hoffmann
        Title: Senior Vice President,
               General Counsel


        HARRIS TRUST COMPANY OF CALIFORNIA


        By:  /s/ John A. Castellanos
             --------------------------------
        Name:  John A. Castellanos
        Title: Vice President



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