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                                                                    EXHIBIT 4.07

                            ILLUMINET HOLDINGS, INC.
                        1999 EMPLOYEE STOCK PURCHASE PLAN

                                    ARTICLE I

                                    Purposes

         Illuminet Holdings, Inc. has established the Plan set forth herein in
order to encourage ownership of its Common Stock by its employees and employees
of its Affiliates, by providing them a convenient means for regular and
systematic purchases on an advantageous basis, thereby increasing their interest
in the Company's success. The Plan is intended to constitute an "employee stock
purchase plan" within the meaning of Section 423(b) of the Internal Revenue Code
of 1986, as amended.

                                   ARTICLE II

                                   Definitions

         "Affiliate" means a subsidiary of the Company (including corporations
becoming subsidiaries subsequent to the adoption of the Plan) within the meaning
of Section 424(f) of the Code that has been designated by the Committee as an
Affiliate for purposes of the Plan.

         "Board" means the Company's Board of Directors.

         "Code" means the Internal Revenue Code of 1986, as amended, and
regulations thereunder.

         "Committee" means the Committee appointed by the Board pursuant to
Article VIII hereof.

         "Company" means Illuminet Holdings, Inc.

         "Effective Date" shall mean October 7, 1999.

         "Employee" means a person employed by an Employer.

         "Employee Contributions" means contributions in the form of payroll
deductions for payment for stock to be purchased by that Employee as provided by
Section 5.1 hereof.

         "Employer" means the Company and any Affiliate that is designated by
the Committee as an employer for purposes of this Plan.

         "Option" means a right to purchase Stock granted under Section 4.1.

         "Option Period" means the period beginning on the Effective Date and
ending April 6, 2000, the period beginning on the Effective Date and ending
October 6, 2000, the period beginning on the Effective Date and ending April 6,
2001, and the period beginning on the Effective Date and ending October 6, 2001;
provided, however, that for any Employee who does not elect to participate in
the Plan as of the Effective Date or who withdraws from the Plan, and who
subsequently elects to participate in the Plan, the term "Option Period" shall
mean each period beginning on the next succeeding six-month anniversary of the
Effective Date and ending on the remaining ending dates of the Option Periods
set out above. If the date on which an Option Period would otherwise end is not
a business day, then the Option Period shall end on the last business day
immediately prior thereto.



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         "Plan" means the Illuminet Holdings, Inc. 1999 Employee Stock Purchase
Plan set forth herein, as amended from time to time.

         "Plan Agent" means the brokerage firm which has been appointed Plan
Agent by the Company to administer and maintain the records for the Plan or such
other Plan Agent who is appointed to act in such capacity by the Committee set
forth in Article VIII hereof.

         "Stock" means the Common Stock of the Company.

                                   ARTICLE III

                                   Eligibility

         An Employee shall be eligible for an Option if he is an Employee of an
Employer regularly scheduled to work 20 hours or more per week, and if he has
been employed by the Employer immediately preceding the first day of the Option
Period. For purposes of determining an Employee's period of employment with the
Employer, such period of employment shall include an Employee's employment with
any business entity, the assets, business or stock of which has been acquired,
in whole or in part, by the Employer through purchase, merger or otherwise. In
addition, an Employee of an Affiliate shall be deemed to have been employed with
an Employer as of the first day of his employment with such Affiliate prior to
its date of affiliation with the Company.

                                   ARTICLE IV

                               Granting of Options

4.1      Option Periods

         On the first day of each Option Period, each Employee who is eligible
for an Option under Article III shall be granted an Option to purchase Stock
from the Company on the last day of each Option Period, by authorizing Employee
Contributions under Article V. Notwithstanding the foregoing, no Employee shall
be eligible for an Option under Article III if such Employee, immediately after
the Option is granted, shall own 5% or more of the total combined voting power
or value of all classes of stock of the Company or of any of its Affiliates,
treating the maximum amount of stock available to him under the Plan for such
Option Period and shares subject to any other option as owned by him and
treating as owned by him shares owned by others to the extent provided in
Section 424(d) of the Code. Any Options granted in an Option Period which are
not exercised on the last day of the last Option Period shall expire as of the
end of the last Option Period.

4.2      Amount of Stock Available

         An aggregate of 700,000 shares of Stock shall be available for purchase
under the Plan, subject to adjustment under Section 4.7. To the extent Options
expire unexercised, the Stock subject to such Options shall become available for
subsequent grant. Stock available for purchase under the Plan shall be
authorized but unissued shares or reacquired shares purchased on the open
market.

4.3      Exercise Price

         For each Option granted on the Effective Date, the purchase price per
share shall be 85% of its IPO Price or 85% of its fair market value on the last
day of the Option Period, whichever is lower, subject to adjustment under
Section 4.7. For each Option granted subsequent to the Effective Date, the
purchase price per share shall be the lesser of (i) the greater of 85% of the
IPO Price or 85% of its fair market value on the first day of the Option Period
or (ii) 85% of the fair market value on the last day of the Option Period. IPO
Price means the price at which stock is initially offered to the public on the
Effective Date. Fair market value on any day means the closing price on the
National Association of Securities Dealers Automated Quotation National Market
System (the "NASDAQ-NMS") on such day or, if not traded on such day, on the last
preceding day on which the stock was traded, or, if not traded on the NASDAQ-NMS
on such exchange or market as the Stock from time to time may be traded if such
market or


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exchange is designated by the Committee as controlling for purposes of the Plan.

4.4      Nontransferability

         Options granted to an Employee are not transferable, and may be
exercised during the Employee's lifetime only by him. Any attempt of assignment,
transfer, pledge, hypothecation or other disposition of any Option contrary to
the provisions of this Plan, and the levy and attachment or any similar
proceedings upon any Option, shall be null and void.

4.5      Board and Stockholder Approval

         The Plan was approved by the Board on October 4, 1999. If the Plan is
not approved by the Company's stockholders prior to October 4, 2000, the Plan
shall be null and void.

4.6      Limits on Stock Purchase

         Notwithstanding any other provision of this Plan, no Employee may
purchase in any calendar year more than the number of shares equal to 15% of his
annual cash compensation divided by 85% of the purchase price of the Stock, both
determined on the first day of an Option Period. In addition, no Employee may be
granted an Option which permits him to purchase during a calendar year under the
Plan and any other employee stock purchase plan, within the meaning of Section
423 of the Code, shares of the Company and its Affiliates having an aggregate
fair market value, determined at the time such Option is granted, of more than
$25,000.

4.7      Adjustment of Amount of Stock

         In the event of change in the number of shares of Stock outstanding by
reason of a Stock dividend, Stock split or other recapitalization, or by reason
of a merger or consolidation or otherwise, the number of shares of Stock
available under this Plan, and the fair market value of such shares at the
beginning of the Option Period during which such change occurs, shall be
adjusted in such manner as the Committee, in its discretion, deems equitable and
appropriate.

                                    ARTICLE V

                                PAYMENT FOR STOCK

5.1      Employee Contributions

         Each Employee may exercise Options granted to him under Section 4.1 by
authorizing Employee Contributions in accordance with instruction from his
Employer. The actual exercise of the Options shall occur on the last day of the
Option Period. Employee Contributions may be authorized beginning with the first
paycheck issued after the end of the enrollment period for an Option Period in
amounts up to 15%, with a minimum of 1%, of an Employee's cash compensation
(before any other voluntary or required withholdings) paid by the Employer. To
the extent that an Employee's cash compensation, after other voluntary and
required withholdings, is not sufficient to cover the Employee's Contributions
elected under this Plan, the Employee's Contributions under this Plan shall be
reduced. Total deductions may not exceed $25,000 for any calendar year. An
authorization for Employee Contributions hereunder shall remain in effect until
changed under Section 5.3.

5.2      Purchase of Stock

         As of the last day of each Option Period the amount of Employee
Contributions during such Option Period for each person who remains an Employee
on such date shall be used to purchase from the Company full shares of Stock,
but no fractional shares shall be purchased. Any Employee contributions
remaining attributable to fractional shares shall be applied to purchase Stock
during the next Option Period, and at the conclusion of the final Option Period
shall be refunded to Employees. Upon the purchase of shares of Stock under an
Option, if requested by the Employee, the Plan Agent shall issue a stock
certificate for such whole shares with a restrictive legend, if applicable.



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5.3      Discontinuance or Change

         An Employee may discontinue Employee Contributions authorized under
Section 5.1 at any time, or change the rate of payroll deductions to any other
permitted rate as of any six-month anniversary of the Effective Date, within the
time prescribed in rules and regulations adopted under Article VIII in
accordance with instructions from his Employer. Once discontinued hereunder,
Employee Contributions may not be made again until the next succeeding Option
Period.

5.4      Refund of Contributions

         If during an Option Period an Employee for whom contributions are being
made under Section 5.1 becomes ineligible to have Stock purchased for him under
Section 5.2, or discontinues his contributions under Section 5.3, his Employee
Contributions during such Option Period shall, at his election, either (a) be
returned without interest to him within 30 days of the date on which the Company
first learns of the Employee's ineligibility or date on which the Employee
informs the Company that he wishes to discontinue contributions, or (b) used to
purchase as many shares as possible at the end of the current Option Period. If
the aggregate amount of Employee Contributions under Section 5.1 during any
Option Period exceeds the purchase price of Stock available under the Plan, the
available Stock shall be allocated to Employees in proportion to the respective
maximum number of shares that can be purchased during the Option Period, and
amounts not used to purchase Stock shall be returned without interest to the
respective Employees as soon as practicable. Any Employee Contributions in
excess of the limits in Section 4.6 shall be returned without interest to an
Employee within 30 days of the date on which the Company first learns of the
existence of any excess contributions.

5.5      Rights of Employees

         An Employee shall have no right, title or interest in any Stock subject
to an Option, including no right to receive dividends, until such Stock has been
purchased for him and credited to his account or issued to him.

5.6      Requirements of Securities Laws

         No shares of Stock may be issued under any Option until all
requirements of applicable federal, state or other securities laws, and of any
securities exchange or market upon which Stock may be listed, with respect to
the purchase, sale and issuance of the Stock shall have been satisfied. If any
action must be taken because of such requirements, then the purchase, sale and
issuance of the shares shall be postponed until such action can reasonably be
taken.

                                   ARTICLE VI

                                 APPLICABLE LAW

         Options granted under this Plan shall be construed and shall take
effect in accordance with the laws of the State of Delaware.

                                   ARTICLE VII

                             AMENDMENT; TERMINATION

7.1      Amendment

         The Board may amend this Plan at any time in such manner and to such
extent as it deems appropriate; provided, that no such amendment shall, without
approval of the stockholders of the Company, increase the number of shares of
Stock available for purchase under the Plan, except as provided in Section 4.7.

7.2      Termination



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         This Plan may be terminated by the Board at any time, in its entirety
or as to any group of Employees. If the Plan is terminated by the Board under
this Article VII on or prior to the last day of the Option Period during which
the Plan is terminated, then, notwithstanding the foregoing, no Stock shall be
purchased as of the last day of such Option Period and each Employee's Employee
Contributions during such Option Period shall be returned without interest to
him within 30 days.

                                  ARTICLE VIII

                                 ADMINISTRATION

         A Committee of persons appointed by the Board of Directors shall have
the authority and responsibility for administration of the Plan. The Board may
from time to time appoint or dismiss members of the Committee. The Board may
prescribe, amend and rescind, and the Committee may adopt, rules and regulations
for administration of the Plan, and the Committee shall have full power and
authority to construe and interpret the Plan. A majority of the members of the
Committee shall constitute a quorum and the acts of a majority of the members
present at a meeting or the consent in writing signed by all members of the
Committee shall be the acts of the Committee and shall be final, conclusive and
binding upon all parties, including the Company, its Affiliates, the
stockholders, the Employees and all persons or entities claiming by or through
the Employees. The Board may correct any defect or any omission or reconcile any
inconsistency in the Plan or in any Option granted hereunder in the manner and
to the extent it shall deem desirable. The expenses of the Plan shall be paid
for by the Company.

                                   ARTICLE IX

                LIMITS ON SALE OF STOCK PURCHASED UNDER THE PLAN

         The Plan is intended to provide shares of Common Stock for investment
and not for resale. The Company does not, however, intend to restrict or
influence any employee in the conduct of his or her own affairs. An employee
may, therefore, sell stock purchased under the Plan at any time the employee
chooses, subject to compliance with any applicable federal or state securities
laws and subject to any restrictions to ensure that tax withholding obligations
are satisfied. THE EMPLOYEE ASSUMES THE RISK OF ANY MARKET FLUCTUATIONS IN THE
PRICE OF THE STOCK.

                                    ARTICLE X

                              APPLICATION OF FUNDS

         The proceeds received by the Company from the sale of Stock pursuant to
Options granted under the Plan will be used for general corporate purposes.

                                   ARTICLE XI

                 NOTICE TO COMPANY OF DISQUALIFYING DISPOSITION

         By electing to participate in the Plan, each Employee agrees to notify
the Company in writing immediately after the Employee transfers Stock acquired
under the Plan, if such transfer occurs within two years after the first
business day of the Option Period in which such Stock was acquired or within one
year from the date of purchase of the Stock. Each Employee further agrees to
provide any information about such a transfer as may be requested by the Company
or any subsidiary corporation in order to assist it in complying with the tax
laws. Such dispositions generally are treated as "disqualifying dispositions"
under Sections 421 and 424 of the Code, which have certain tax consequences to
participants and to the Company and its participating subsidiaries.

                                   ARTICLE XII

                     WITHHOLDING OF ADDITIONAL INCOME TAXES



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By electing to participate in the Plan, each Employee acknowledges that the
Company and its participating subsidiaries may be required to withhold taxes
with respect to the Employee's participation in the Plan, and each Employee
agrees that the Company and its participating subsidiaries may deduct additional
amounts from the Employee's compensation, when amounts are added to the
Employee's account, used to purchase Stock or refunded, in order to satisfy such
withholding obligations. Each Employee further acknowledges that when Stock is
purchased under the Plan the Company and its participating subsidiaries may be
required to withhold taxes with respect to all or a portion of the difference
between the fair market value of the Common Stock purchased and its purchase
price, and each Employee agrees that such taxes may be withheld from
compensation otherwise payable to such Employee. It is intended that tax
withholding will be accomplished in such a manner that the full amount of
payroll deductions elected by the Employee under Article V will be used to
purchase Common Stock. However, if amounts sufficient to satisfy applicable tax
withholding obligations have not been withheld from compensation otherwise
payable to any Employee, then, notwithstanding any other provision of the Plan,
the Company may withhold such taxes from the Employee's accumulated payroll
deductions and apply the net amount to the purchase of Stock, unless the
Employee pays to the Company, prior to the exercise date, an amount sufficient
to satisfy such withholding obligations. Each Employee further acknowledges that
the Company and its participating subsidiaries may be required to withhold taxes
in connection with the disposition of stock acquired under the Plan and agrees
that the Company or any participating subsidiary may take whatever action it
considers appropriate to satisfy such withholding requirements, including
deducting from compensation otherwise payable to such Employee an amount
sufficient to satisfy such withholding requirements or conditioning any
disposition of Stock by the Employee upon the payment to the Company or such
subsidiary of an amount sufficient to satisfy such withholding requirements.



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