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                                                                     EXHIBIT 4.4

                       LEAP WIRELESS INTERNATIONAL, INC.
                        1998 EMPLOYEE STOCK PURCHASE PLAN

                     ADOPTED BY THE BOARD SEPTEMBER 8, 1998
                          EFFECTIVE SEPTEMBER 23, 1998
                 APPROVED BY THE STOCKHOLDERS SEPTEMBER 8, 1998
                         LAST AMENDED FEBRUARY 7, 2001
              AMENDMENT APPROVED BY THE STOCKHOLDERS APRIL 19, 2001

1.      PURPOSE.

        (a) The purpose of the 1998 Employee Stock Purchase Plan (the "Plan") is
to provide a means by which employees of Leap Wireless International, Inc., a
Delaware corporation (the "Company"), and its Affiliates, as defined in
subparagraph 1(b), which are designated as provided in subparagraph 2(b), may be
given an opportunity to purchase stock of the Company.

        (b) The word "Affiliate" as used in the Plan means any parent
corporation or subsidiary corporation of the Company, as those terms are defined
in Sections 424(e) and (f), respectively, of the Internal Revenue Code of 1986,
as amended (the "Code").

        (c) The Company, by means of the Plan, seeks to retain the services of
its employees, to secure and retain the services of new employees, and to
provide incentives for such persons to exert maximum efforts for the success of
the Company.

        (d) The Company intends that the rights to purchase stock of the Company
granted under the Plan be considered options issued under an "employee stock
purchase plan" as that term is defined in Section 423(b) of the Code.

2.      ADMINISTRATION.

        (a) The Plan shall be administered by the Board of Directors (the
"Board") of the Company unless and until the Board delegates administration to a
Committee, as provided in subparagraph 2(c). Whether or not the Board has
delegated administration, the Board shall have the final power to determine all
questions of policy and expediency that may arise in the administration of the
Plan.

        (b) The Board shall have the power, subject to, and within the
limitations of, the express provisions of the Plan:

               (i) To determine when and how rights to purchase stock of the
Company shall be granted and the provisions of each offering of such rights
(which need not be identical).

               (ii) To designate from time to time which Affiliates of the
Company shall be eligible to participate in the Plan.

               (iii) To construe and interpret the Plan and rights granted under
it, and to establish, amend and revoke rules and regulations for its
administration. The Board, in the


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exercise of this power, may correct any defect, omission or inconsistency in the
Plan, in a manner and to the extent it shall deem necessary or expedient to make
the Plan fully effective.

               (iv) To amend the Plan as provided in paragraph 13.

               (v) Generally, to exercise such powers and to perform such acts
as the Board deems necessary or expedient to promote the best interests of the
Company and its Affiliates and to carry out the intent that the Plan be treated
as an "employee stock purchase plan" within the meaning of Section 423 of the
Code.

        (c) The Board may delegate administration of the Plan to a Committee
composed of two (2) or more members of the Board (the "Committee"). If
administration is delegated to a Committee, the Committee shall have, in
connection with the administration of the Plan, the powers theretofore possessed
by the Board, subject, however, to such resolutions, not inconsistent with the
provisions of the Plan, as may be adopted from time to time by the Board. The
Board may abolish the Committee at any time and revest in the Board the
administration of the Plan.

3.      SHARES SUBJECT TO THE PLAN.

        (a) Subject to the provisions of paragraph 12 relating to adjustments
upon changes in stock, the stock that may be sold pursuant to rights granted
under the Plan shall not exceed in the aggregate five hundred thousand (500,000)
shares of the Company's common stock (the "Common Stock"). If any right granted
under the Plan shall for any reason terminate without having been exercised, the
Common Stock not purchased under such right shall again become available for the
Plan.

        (b) The stock subject to the Plan may be unissued shares or reacquired
shares, bought on the market or otherwise.

4.      GRANT OF RIGHTS; OFFERING.

        (a) The Board or the Committee may from time to time grant or provide
for the grant of rights to purchase Common Stock of the Company under the Plan
to eligible employees (an "Offering") on a date or dates (the "Offering
Date(s)") selected by the Board or the Committee. Each Offering shall be in such
form and shall contain such terms and conditions as the Board or the Committee
shall deem appropriate, which shall comply with the requirements of Section
423(b)(5) of the Code that all employees granted rights to purchase stock under
the Plan shall have the same rights and privileges. The terms and conditions of
an Offering shall be incorporated by reference into the Plan and treated as part
of the Plan. The provisions of separate Offerings need not be identical, but
each Offering shall include (through incorporation of the provisions of this
Plan by reference in the document comprising the Offering or otherwise) the
period during which the Offering shall be effective, which period shall not
exceed twenty-seven (27) months beginning with the Offering Date, and the
substance of the provisions contained in paragraphs 5 through 8, inclusive.

        (b) If an employee has more than one right outstanding under the Plan,
unless he or she otherwise indicates in agreements or notices delivered
hereunder: (1) each agreement or

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notice delivered by that employee will be deemed to apply to all of his or her
rights under the Plan, and (2) a right with a lower exercise price (or an
earlier-granted right, if two rights have identical exercise prices), will be
exercised to the fullest possible extent before a right with a higher exercise
price (or a later-granted right, if two rights have identical exercise prices)
will be exercised.

5.      ELIGIBILITY.

        (a) Rights may be granted only to employees of the Company or, as the
Board or the Committee may designate as provided in subparagraph 2(b), to
employees of any Affiliate of the Company. Except as provided in subparagraph
5(b), an employee of the Company or any Affiliate shall not be eligible to be
granted rights under the Plan, unless, on the Offering Date, such employee has
been in the employ of the Company or any Affiliate for such continuous period
preceding such grant as the Board or the Committee may require, but in no event
shall the required period of continuous employment be equal to or greater than
two (2) years. In addition, unless otherwise determined by the Board or the
Committee and set forth in the terms of the applicable Offering, no employee of
the Company or any Affiliate shall be eligible to be granted rights under the
Plan, unless, on the Offering Date, such employee's customary employment with
the Company or such Affiliate is for at least twenty (20) hours per week and at
least five (5) months per calendar year.

        (b) The Board or the Committee may provide that each person who, during
the course of an Offering, first becomes an eligible employee of the Company or
designated Affiliate will, on a date or dates specified in the Offering which
coincides with the day on which such person becomes an eligible employee or
occurs thereafter, receive a right under that Offering, which right shall
thereafter be deemed to be a part of that Offering. Such right shall have the
same characteristics as any rights originally granted under that Offering, as
described herein, except that:

               (i) the date on which such right is granted shall be the
"Offering Date" of such right for all purposes, including determination of the
exercise price of such right;

               (ii) the period of the Offering with respect to such right shall
begin on its Offering Date and end coincident with the end of such Offering; and

               (iii) the Board or the Committee may provide that if such person
first becomes an eligible employee within a specified period of time before the
end of the Offering, he or she will not receive any right under that Offering.

        (c) No employee shall be eligible for the grant of any rights under the
Plan if, immediately after any such rights are granted, such employee owns stock
possessing five percent (5%) or more of the total combined voting power or value
of all classes of stock of the Company or of any Affiliate. For purposes of this
subparagraph 5(c), the rules of Section 424(d) of the Code shall apply in
determining the stock ownership of any employee, and stock which such employee
may purchase under all outstanding rights and options shall be treated as stock
owned by such employee.

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        (d) An eligible employee may be granted rights under the Plan only if
such rights, together with any other rights granted under "employee stock
purchase plans" of the Company and any Affiliates, as specified by Section
423(b)(8) of the Code, do not permit such employee's rights to purchase stock of
the Company or any Affiliate to accrue at a rate which exceeds twenty-five
thousand dollars ($25,000) of fair market value of such stock (determined at the
time such rights are granted) for each calendar year in which such rights are
outstanding at any time.

        (e) Officers of the Company and any designated Affiliate shall be
eligible to participate in Offerings under the Plan, provided, however, that the
Board may provide in an Offering that certain employees who are highly
compensated employees within the meaning of Section 423(b)(4)(D) of the Code
shall not be eligible to participate.

6.      RIGHTS; PURCHASE PRICE.

        (a) On each Offering Date, each eligible employee, pursuant to an
Offering made under the Plan, shall be granted the right to purchase up to the
number of shares of Common Stock of the Company purchasable with (i) a
percentage designated by the Board or the Committee of such employee's Earnings
(as defined in subparagraph 7(a)) during the period which begins on the Offering
Date (or such later date as the Board or the Committee determines for a
particular Offering) and ends on the date stated in the Offering, which date
shall be no later than the end of the Offering, plus (ii) any additional amount
which the Board or the Committee has designated may be contributed by an
employee apart from payroll deductions from such employee's Earnings. The Board
or the Committee shall establish one or more dates during an Offering (the
"Purchase Date(s)") on which rights granted under the Plan shall be exercised
and purchases of Common Stock carried out in accordance with such Offering.

        (b) In connection with each Offering made under the Plan, the Board or
the Committee may specify a maximum number of shares that may be purchased by
any employee as well as a maximum aggregate number of shares that may be
purchased by all eligible employees pursuant to such Offering. In addition, in
connection with each Offering that contains more than one Purchase Date, the
Board or the Committee may specify a maximum aggregate number of shares which
may be purchased by all eligible employees on any given Purchase Date under the
Offering. If the aggregate purchase of shares upon exercise of rights granted
under the Offering would exceed any such maximum aggregate number, the Board or
the Committee shall make a pro rata allocation of the shares available in as
nearly a uniform manner as shall be practicable and as it shall deem to be
equitable.

        (c) The purchase price of stock acquired pursuant to rights granted
under the Plan shall be not less than the lesser of:

               (i) an amount equal to eighty-five percent (85%) of the fair
market value of the stock on the Offering Date; or

               (ii) an amount equal to eighty-five percent (85%) of the fair
market value of the stock on the Purchase Date.

        (d) For purposes of this Plan, "fair market value" means, as of any
date, the value of the Common Stock of the Company determined as follows:

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               (i) If the Common Stock is listed on any established stock
exchange or traded on the Nasdaq National Market or the Nasdaq SmallCap Market,
the Fair Market Value of a share of Common Stock shall be the closing price for
which the stock was sold (or the closing bid, if no sales were reported) as
quoted on such exchange or market (or the exchange or market with the greatest
volume of trading in the Common Stock) on the last market trading day prior to
the day of determination, as reported in THE WALL STREET JOURNAL or such other
source as the Board deems reliable;

               (ii) if the Common Stock is quoted on the Nasdaq System (but not
on the National Market System thereof) or is regularly quoted by a recognized
securities dealer but selling prices are not reported, the fair market value of
a share of Common Stock shall be the closing price for the Common Stock on the
last market trading day prior to the date as of which the determination is to be
made, as reported in the Wall Street Journal or such other sources as the Board
deems reliable;

               (iii) in the absence of an established market for the Common
Stock, the fair market value shall be determined in good faith by the Board.

        (e) For purposes of an Offering, if there is an established market for
the Company's Common Stock and the date as of which the "fair market value" is
to be determined is not a trading day on such established market, then solely
for the purpose of determining "fair market value" such date shall be:

               (i) in the case of the Offering Date, the first market trading
day following the Offering Date; and

               (ii) in the case of the Purchase Date, the last market trading
day prior to the Purchase Date.

7.      PARTICIPATION; WITHDRAWAL; TERMINATION.

        (a) An eligible employee may become a participant in the Plan pursuant
to an Offering by delivering a participation agreement to the Company within the
time specified in the Offering, in such form as the Company provides. Each such
agreement shall authorize payroll deductions of up to the maximum percentage
specified by the Board or the Committee of such employee's Earnings during the
Offering. "Earnings" is defined as an employee's regular salary or wages
(including amounts thereof elected to be deferred by the employee, that would
otherwise have been paid, under any arrangement established by the Company
intended to comply with Section 401(k), Section 402(e)(3), Section 125, Section
402(h), or Section 403(b) of the Code, and also including any deferrals under a
non-qualified deferred compensation plan or arrangement established by the
Company), and may also include or exclude (as provided for each Offering) the
following items of compensation: bonuses, commissions, overtime pay, incentive
pay, profit sharing, other remuneration paid directly to the employee, the cost
of employee benefits paid for by the Company or an Affiliate, education or
tuition reimbursements, imputed income arising under any group insurance or
benefit program, traveling expenses, business and moving expense reimbursements,
income received in connection with stock options, contributions made by the
Company or an Affiliate under any employee benefit plan,

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and similar items of compensation, as determined by the Board or Committee. The
payroll deductions made for each participant shall be credited to an account for
such participant under the Plan and shall be deposited with the general funds of
the Company. A participant may reduce (including to zero) such payroll
deductions on only one occasion during an Offering. An eligible employee may
begin payroll deductions or increase such payroll deductions only prior to the
beginning of any new Offering to be effective on the first day of the Offering.
A participant may make additional payments into his or her account only if
specifically provided for in the Offering and only if the participant has not
had the maximum amount withheld during the Offering.

        (b) At any time during an Offering, a participant may terminate his or
her payroll deductions under the Plan and withdraw from the Offering by
delivering to the Company a notice of withdrawal in such form as the Company
provides. Such withdrawal may be elected at any time prior to the end of the
Offering except as provided by the Board or the Committee in the Offering. Upon
such withdrawal from the Offering by a participant, the Company shall distribute
to such participant all of his or her accumulated payroll deductions (reduced to
the extent, if any, such deductions have been used to acquire stock for the
participant) under the Offering, without interest, and such participant's
interest in that Offering shall be automatically terminated. A participant's
withdrawal from an Offering will have no effect upon such participant's
eligibility to participate in any other Offerings under the Plan but such
participant will be required to deliver a new participation agreement in order
to participate in subsequent Offerings under the Plan.

        (c) Rights granted pursuant to any Offering under the Plan shall
terminate immediately upon cessation of a participant's employment with the
Company and any designated Affiliate, for any reason, and the Company shall
distribute to such terminated employee all of his or her accumulated payroll
deductions (reduced to the extent, if any, such deductions have been used to
acquire stock for the terminated employee), under the Offering, without
interest.

        (d) Rights granted under the Plan shall not be transferable by a
participant, and shall be exercisable only by the participant to whom such
rights are granted.

8.      EXERCISE.

        (a) On each Purchase Date specified in the relevant Offering, each
participant's accumulated payroll deductions and other additional payments
specifically provided for in the Offering (without any increase for interest)
will be applied to the purchase of whole shares of stock of the Company, up to
the maximum number of shares permitted pursuant to the terms of the Plan and the
applicable Offering, at the purchase price specified in the Offering. No
fractional shares shall be issued upon the exercise of rights granted under the
Plan, unless the Offering document specifically provides otherwise. The amount,
if any, of accumulated payroll deductions remaining in each participant's
account after the purchase of shares which is less than the amount required to
purchase one share of stock on the final Purchase Date of an Offering shall be
held in each such participant's account for the purchase of shares under the
next Offering under the Plan, unless such participant withdraws from such next
Offering, as provided in subparagraph 7(b), or is no longer eligible to be
granted rights under the Plan, as provided in paragraph 5, in which case such
amount shall be distributed to the participant after such final

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Purchase Date, without interest. The amount, if any, of accumulated payroll
deductions remaining in any participant's account after the purchase of shares
which is equal to the amount required to purchase whole shares of stock on the
final Purchase Date of an Offering shall be distributed in full to the
participant after such Purchase Date, without interest.

        (b) No rights granted under the Plan may be exercised to any extent
unless the shares to be issued upon such exercise under the Plan (including
rights granted thereunder) are covered by an effective registration statement
pursuant to the Securities Act of 1933, as amended (the "Securities Act") and
the Plan is in material compliance with all applicable state, foreign and other
securities and other laws applicable to the Plan. If on a Purchase Date in any
Offering hereunder the Plan is not so registered or in such compliance, no
rights granted under the Plan or any Offering shall be exercised on such
Purchase Date, and the Purchase Date shall be delayed until the Plan is subject
to such an effective registration statement and such compliance, except that the
Purchase Date shall not be delayed more than twelve (12) months and the Purchase
Date shall in no event be more than twenty-seven (27) months from the Offering
Date. If on the Purchase Date of any Offering hereunder, as delayed to the
maximum extent permissible, the Plan is not registered and in such compliance,
no rights granted under the Plan or any Offering shall be exercised and all
payroll deductions accumulated during the Offering (reduced to the extent, if
any, such deductions have been used to acquire stock) shall be distributed to
the participants, without interest.

9.      COVENANTS OF THE COMPANY.

        (a) During the terms of the rights granted under the Plan, the Company
shall keep available at all times the number of shares of stock required to
satisfy such rights.

        (b) The Company shall seek to obtain from each federal, state, foreign
or other regulatory commission or agency having jurisdiction over the Plan such
authority as may be required to issue and sell shares of stock upon exercise of
the rights granted under the Plan. If, after reasonable efforts, the Company is
unable to obtain from any such regulatory commission or agency the authority
which counsel for the Company deems necessary for the lawful issuance and sale
of stock under the Plan, the Company shall be relieved from any liability for
failure to issue and sell stock upon exercise of such rights unless and until
such authority is obtained.

10.     USE OF PROCEEDS FROM STOCK.

        Proceeds from the sale of stock pursuant to rights granted under the
Plan shall constitute general funds of the Company.

11.     RIGHTS AS A STOCKHOLDER.

        A participant shall not be deemed to be the holder of, or to have any of
the rights of a holder with respect to, any shares subject to rights granted
under the Plan unless and until the participant's shares acquired upon exercise
of rights hereunder are recorded in the books of the Company.

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12.     ADJUSTMENTS UPON CHANGES IN STOCK.

        (a) If any change is made in the stock subject to the Plan, or subject
to any rights granted under the Plan (through merger, consolidation,
reorganization, recapitalization, stock dividend, dividend in property other
than cash, stock split, liquidating dividend, combination of shares, exchange of
shares, change in corporate structure or other transaction not involving the
receipt of consideration by the Company), the Plan and outstanding rights will
be appropriately adjusted in the class(es) and maximum number of shares subject
to the Plan and the class(es) and number of shares and price per share of stock
subject to outstanding rights. Such adjustments shall be made by the Board or
the Committee, the determination of which shall be final, binding and
conclusive. (The conversion of any convertible securities of the Company shall
not be treated as a "transaction not involving the receipt of consideration by
the Company.")

        (b) In the event of: (1) a dissolution or liquidation of the Company,
(2) the sale of all or substantially all of the Company's assets, (3) a merger,
consolidation or reorganization of the Company with or into another corporation
or other legal person, other than a merger, consolidation or reorganization in
which more than fifty percent (50%) of the combined voting power of the
then-outstanding securities of the surviving entity (or if more than one entity
survives the transaction, the controlling entity) immediately after such a
transaction are held in the aggregate by holders of voting securities of the
Company immediately prior to such transaction, (4) the acquisition by any person
(within the meaning of Section 13(d)(3) or Section 14(d)(2) of the Exchange Act)
of beneficial ownership (within the meaning of Rule 13d-3 or any successor rule
or regulation promulgated under the Exchange Act) of securities representing
fifty percent (50%) or more of the combined voting power of the then-outstanding
securities of the Company, or (5) during any period of two (2) consecutive
years, individuals who at the beginning of any such period constitute the
Directors of the Company (the "Incumbent Directors") cease for any reason to
constitute at least a majority thereof unless the election or the nomination for
election by the Company's stockholders of a Director of the Company first
elected during such period was approved by the vote of at least two-thirds of
the Incumbent Directors, whereupon such Director shall also be classified as an
Incumbent Director (collectively, a "Change in Control"), then, as determined by
the Board in its sole discretion prior to a Change in Control, (i) any surviving
or acquiring corporation may assume outstanding rights or substitute similar
rights for those under the Plan, (ii) such rights may continue in full force and
effect, or (iii) participants' accumulated payroll deductions may be used to
purchase Common Stock as of the date immediately prior (after, in the case of a
Change in Control described in subsection 12(b)(5)) to a Change in Control
described above and the participants' rights under the ongoing Offering
terminated.

13.     AMENDMENT OF THE PLAN.

        (a) The Board at any time, and from time to time, may amend the Plan.
However, except as provided in paragraph 12 relating to adjustments upon changes
in stock, no amendment shall be effective unless approved by the stockholders of
the Company within twelve (12) months before or after the adoption of the
amendment if such amendment requires stockholder approval in order for the Plan
to obtain employee stock purchase plan treatment under Section 423 of the Code
or to comply with the requirements of Rule 16b-3 promulgated under the Exchange
Act or any Nasdaq or securities exchange requirements.

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        (b) The Board may amend the Plan in any respect the Board deems
necessary or advisable to provide eligible employees with the maximum benefits
provided or to be provided under the provisions of the Code and the regulations
promulgated thereunder relating to employee stock purchase plans and/or to bring
the Plan and/or rights granted under it into compliance therewith.

        (c) Rights and obligations under any rights granted before amendment of
the Plan shall not be impaired by any amendment of the Plan, except with the
consent of the person to whom such rights were granted, or except as necessary
to comply with any laws or governmental regulations, or except as necessary to
ensure that the Plan and/or rights granted under the Plan comply with the
requirements of Section 423 of the Code.

14.     TERMINATION OR SUSPENSION OF THE PLAN.

        (a) The Board in its discretion, may suspend or terminate the Plan at
any time. No rights may be granted under the Plan while the Plan is suspended or
after it is terminated.

        (b) Rights and obligations under any rights granted while the Plan is in
effect shall not be altered or impaired by suspension or termination of the
Plan, except as expressly provided in the Plan or (if impaired) with the consent
of the person to whom such rights were granted, or except as necessary to comply
with any laws or governmental regulation, or except as necessary to ensure that
the Plan and/or rights granted under the Plan comply with the requirements of
Section 423 of the Code.

15.     EFFECTIVE DATE OF PLAN.

        The Plan shall become effective upon the date determined by the Board
(the "Effective Date"), but no rights granted under the Plan shall be exercised
unless and until the Plan has been approved by the stockholders of the Company
within twelve (12) months before or after the date the Plan is adopted by the
Board or the Committee, which date may be prior to the Effective Date.

                                       9.