MASERGY COMMUNICATIONS, INC. EMPLOYEE STOCK PURCHASE PLAN

Exhibit 10.4

MASERGY COMMUNICATIONS, INC.

EMPLOYEE STOCK PURCHASE PLAN

I. PURPOSE OF THE PLAN

This Employee Stock Purchase Plan is intended to promote the interests of Masergy Communications, Inc., a Delaware corporation, by providing eligible employees with the opportunity to acquire a proprietary interest in the Corporation through participation in a payroll deduction-based employee stock purchase plan designed to qualify under Section 423 of the Code. However, the Corporation may grant purchase rights pursuant to one or more offerings under the Plan that are not intended to meet the requirements of Code Section 423.

Capitalized terms herein shall have the meanings assigned to such terms in the attached Appendix.

II. ADMINISTRATION OF THE PLAN

The Plan Administrator shall have full authority to interpret and construe any provision of the Plan and to adopt such rules and regulations for administering the Plan as it may deem necessary in order to comply with the requirements of Code Section 423 or other applicable law. Decisions of the Plan Administrator shall be final and binding on all parties having an interest in the Plan.

III. STOCK SUBJECT TO PLAN

A. The stock purchasable under the Plan shall be shares of authorized but unissued or reacquired Common Stock, including shares of Common Stock purchased on the open market. The number of shares of Common Stock initially reserved for issuance over the term of the Plan shall be limited to five hundred thousand (500,000) shares.

B. Should any change be made to the Common Stock by reason of any stock split, stock dividend, recapitalization, combination of shares, exchange of shares, spin-off transaction, extraordinary distribution (whether in cash, securities or other property) or other change affecting the outstanding Common Stock as a class without the Corporation’s receipt of consideration, or should the value of the outstanding shares of Common Stock be substantially reduced as a result of a spin-off transaction or an extraordinary dividend or distribution, then equitable adjustments shall be made by the Plan Administrator to (i) the maximum number and class of securities issuable under the Plan, (ii) the maximum number and class of securities purchasable per Participant on any one Purchase Date, (iii) the maximum number and class of securities purchasable in the aggregate by all Participants on any one Purchase Date and (iv) the number and class of securities and the price per share in effect under each outstanding purchase right. The adjustments shall be made in such manner as the Plan Administrator deems appropriate and such adjustments shall be final, binding and conclusive.

IV. OFFERING PERIODS

A. The Plan shall be implemented in one or more offerings. Offerings may be consecutive or overlapping. Each offering shall be in such form and shall contain such terms and conditions as the Plan Administrator shall deem appropriate. The terms of separate offerings need not be identical. In addition, special offerings may be established with respect to entities that are acquired by the Corporation (or any subsidiary of the Corporation) or under such other circumstances as the Plan Administrator deems appropriate. In no event, however, shall the terms and conditions of any offering contravene the express limitations and restrictions of the Plan, and the participants in each separate offering shall have equal rights and privileges under that offering in accordance with the requirements of Section 423(b)(5) of the Code and the applicable Treasury Regulations thereunder.

B. Shares of Common Stock shall be offered for purchase under each offering through a series of overlapping offering periods until such time as (i) the maximum number of shares of Common Stock available for issuance under the Plan shall have been purchased or (ii) the Plan shall have been sooner terminated.

C. Each offering period shall be of such duration (not to exceed twenty-four (24) months) as determined by the Plan Administrator prior to the commencement date of such offering period. Until such time as the Plan Administrator specifies otherwise, offering periods shall be of a duration of twelve (12) months and shall commence on the first business day in March and September each year. However, the initial offering period shall commence at the Effective Time and shall be of such duration as determined by the Plan Administrator (not to exceed twenty-four (24) months).

D. Each offering period shall consist of one or more successive Purchase Intervals. Until such time as the Plan Administrator specifies otherwise, each offering period shall be comprised of two (2) successive Purchase Intervals. Purchase Intervals shall run from the first business day in March to the last business day in August each year and from the first business day in September each year to the last business day in February in the following year. The first Purchase Interval under the initial offering period shall commence at the Effective Time and end on such date as determined by the Plan Administrator.

E. Should the Fair Market Value per share of Common Stock on any Purchase Date within an offering period be less than the Fair Market Value per share of Common Stock on the start date of that offering period, then the individuals participating in such offering period shall, immediately after the purchase of shares of Common Stock on their behalf on such Purchase Date, be transferred from that offering period and automatically enrolled in the offering period commencing on the next business day following such Purchase Date, provided and only if the Fair Market Value per share of Common Stock on the start date of that new offering period is lower than the Fair Market Value per share of Common Stock on the start date of the offering period in which they were currently enrolled. The new offering period shall have a duration of twelve (12) months unless a shorter duration is established by the Plan Administrator within five (5) days following the start date of that offering period.

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V. ELIGIBILITY

A. Purchase rights may be granted under the Plan only to Employees of the Corporation or an Affiliate. Unless otherwise determined by the Plan Administrator for an offering, each individual who is an Eligible Employee on the start date of any offering period under the Plan may enter that offering period on such start date. However, an Eligible Employee may participate in only one offering period at a time.

B. The date an individual enters an offering period shall be designated his or her Entry Date for purposes of that offering period.

C. Except as otherwise provided in Section IV.E above, an Eligible Employee must, in order to participate in the Plan for a particular offering period, complete the enrollment forms prescribed by the Plan Administrator (including a stock purchase agreement and a payroll deduction authorization) and file such forms with the Plan Administrator (or its designate) on or before his or her scheduled Entry Date.

VI. PAYROLL DEDUCTIONS

A. The payroll deduction authorized by the Participant for purposes of acquiring shares of Common Stock during an offering period may be any multiple of one percent (1%) of the Cash Earnings paid to the Participant during each Purchase Interval within that offering period, up to a maximum of eight percent (8%). The deduction rate so authorized shall continue in effect throughout the offering period, except to the extent such rate is changed in accordance with the following guidelines:

(i) The Participant may, at any time during the offering period, reduce his or her rate of payroll deduction to become effective as soon as possible after filing the appropriate form with the Plan Administrator. Unless otherwise determined by the Plan Administrator for an offering, the Participant may not, however, effect more than one (1) such reduction per Purchase Interval.

(ii) The Participant may, prior to the commencement of any new Purchase Interval within the offering period or prior to the start date of any new offering period, increase the rate of his or her payroll deduction by filing the appropriate form with the Plan Administrator. The new rate (which may not exceed the maximum payroll deduction percentage in effect for that offering period) shall become effective on the start date of the first Purchase Interval or first offering period (if earlier) following the filing of such form.

B. Payroll deductions shall begin on the first pay day administratively feasible following the Participant’s Entry Date and shall (unless sooner terminated by the Participant) continue through the pay day ending with or immediately prior to the last day of that offering period. The amounts so collected shall be credited to the Participant’s book account under the Plan, but no interest shall be paid on the balance from time to time outstanding in such account unless otherwise required by applicable law. The amounts collected from the Participant

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shall not be required to be held in any segregated account or trust fund and may be commingled with the general assets of the Corporation and used for general corporate purposes unless otherwise required by applicable law. Payroll deductions collected in a currency other than U.S. Dollars shall be converted into U.S. Dollars on the last day of the Purchase Interval in which collected, with such conversion to be based on the exchange rate determined by the Plan Administrator it its sole discretion.

C. For the initial Purchase Interval of the first offering period under the Plan, no payroll deductions shall be required of the Participant until such time as the Participant affirmatively elects to commence such payroll deductions following his or her receipt of the 1933 Act prospectus for the Plan. In the absence of such payroll deductions, the Participant will be required to contribute the applicable percentage of his or her Cash Earnings to the Plan in a lump sum payment immediately prior to the close of that Purchase Interval should the Participant elect to have shares of Common Stock purchased on his or her behalf on the Purchase Date for that initial Purchase Interval.

D. The Plan Administrator may also permit Employees in one or more subsequent offerings to contribute to the Plan by means other than payroll deductions. Such permitted contributions shall be collected in the manner specified by the Plan Administrator.

E. Payroll deductions (or other permitted contributions) shall automatically cease upon the termination of the Participant’s purchase right in accordance with the provisions of the Plan.

F. The Participant’s acquisition of shares of Common Stock under the Plan on any Purchase Date shall neither limit nor require the Participant’s acquisition of shares of Common Stock on any subsequent Purchase Date, whether within the same or a different offering period.

VII. PURCHASE RIGHTS

A. Grant of Purchase Rights. A Participant shall be granted a separate purchase right for each offering period in which he or she is enrolled. The purchase right shall be granted on the Participant’s Entry Date and shall provide the Participant with the right to purchase shares of Common Stock, in a series of one or more successive installments during that offering period, upon the terms set forth below. Unless the Plan Administrator determines otherwise prior to the start date of the applicable offering period and subject to the limitations of Article VIII below, each purchase right granted for an offering period shall provide the Participant with the right to purchase up to 2,500 shares of Common Stock on each Purchase Date within that offering period for a maximum of 5,000 shares of Common Stock for an offering period comprised of two Purchase Intervals. The Participant shall execute a stock purchase agreement embodying such terms and such other provisions (not inconsistent with the Plan) as the Plan Administrator may deem advisable.

Under no circumstances shall purchase rights be granted under the Plan to any Eligible Employee if such individual would, immediately after the grant, own (within the

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meaning of Code Section 424(d)) or hold outstanding options or other rights to purchase, stock possessing five percent (5%) or more of the total combined voting power or value of all classes of stock of the Corporation or any Affiliate.

B. Exercise of the Purchase Right. Each purchase right shall be automatically exercised in installments on each successive Purchase Date within the offering period, and shares of Common Stock shall accordingly be purchased on behalf of each Participant on each such Purchase Date. The purchase shall be effected by applying the Participant’s payroll deductions (or, to the extent applicable, other form of contribution) for the Purchase Interval ending on such Purchase Date to the purchase of whole shares of Common Stock at the purchase price in effect for the Participant for that Purchase Date.

C. Purchase Price. The purchase price per share at which Common Stock will be purchased on the Participant’s behalf on each Purchase Date within the particular offering period in which he or she is enrolled shall be determined by the Plan Administrator prior to the start of that offering period, but in no event shall be less than eighty-five percent (85%) of the lower of (i) the Fair Market Value per share of Common Stock on the Participant’s Entry Date into that offering period or (ii) the Fair Market Value per share of Common Stock on that Purchase Date.

D. Number of Purchasable Shares. The number of shares of Common Stock purchasable by a Participant on each Purchase Date during an offering period in which he or she is enrolled shall be the number of whole shares obtained by dividing the amount collected from the Participant through payroll deductions (or through other permitted form of calculation) during the Purchase Interval ending with that Purchase Date by the purchase price in effect for the Participant for that Purchase Date. However, the maximum number of shares of Common Stock purchasable per Participant on any one Purchase Date shall not exceed 2,500 shares, subject to periodic adjustments in the event of certain changes in the Corporation’s capitalization. In addition, the maximum number of shares of Common Stock purchasable in total by all Participants on any one Purchase Date shall not exceed 100,000 shares, subject to periodic adjustments in the event of certain changes in the Corporation’s capitalization. However, the Plan Administrator shall have the discretionary authority, exercisable prior to the start of any offering period under the Plan, to increase or decrease the limitations to be in effect for the number of shares purchasable per Participant (and the corresponding maximum number of shares purchasable per Participant for that offering period) and in total by all Participants on each Purchase Date within that offering period.

E. Excess Payroll Deductions. Any payroll deductions (or other permitted form of contribution) not applied to the purchase of Common Stock on any Purchase Date because they are not sufficient to purchase a whole share of Common Stock shall be held for the purchase of Common Stock on the next Purchase Date. However, any payroll deductions (or other permitted form of contribution) not applied to the purchase of Common Stock by reason of the limitation on the maximum number of shares purchasable per Participant or in the aggregate by all Participants on the Purchase Date shall be promptly refunded.

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F. Suspension of Payroll Deductions. In the event that a Participant is, by reason of the accrual limitations in Article VIII, precluded from purchasing additional shares of Common Stock on one or more Purchase Dates during the offering period in which he or she is enrolled, then no further payroll deductions (or other permitted form of contribution) shall be collected from such Participant with respect to those Purchase Dates. The suspension of such deductions (or other permitted form of contribution) shall not terminate the Participant’s purchase right for the offering period in which he or she is enrolled, and payroll deductions (or other permitted form of contribution) shall automatically resume on behalf of such Participant once he or she is again able to purchase shares during that offering period in compliance with the accrual limitations of Article VIII.

G. Withdrawal from Offering Period. The following provisions shall govern the Participant’s withdrawal from an offering period:

(i) A Participant may withdraw from the offering period in which he or she is enrolled at any time prior to the next scheduled Purchase Date by filing the appropriate form with the Plan Administrator (or its designate), and no further payroll deductions (or other permitted form of contribution) shall be collected from the Participant with respect to that offering period. Any payroll deductions (or other permitted form of contribution) collected during the Purchase Interval in which such withdrawal occurs shall, at the Participant’s election, be immediately refunded or held for the purchase of shares on the next Purchase Date. If no such election is made at the time of such withdrawal, then the payroll deductions (or other permitted form of contribution) collected from the Participant during the Purchase Interval in which such withdrawal occurs shall be refunded as soon as possible.

(ii) The Participant’s withdrawal from a particular offering period shall be irrevocable, and the Participant may not subsequently rejoin that offering period at a later date. In order to resume participation in any subsequent offering period, such individual must re-enroll in the Plan (by making a timely filing of the prescribed enrollment forms) on or before his or her scheduled Entry Date into that offering period.

H. Termination of Purchase Right. The following provisions shall govern the termination of outstanding purchase rights:

(i) Should the Participant cease to remain an Eligible Employee for any reason (including death, disability or change in status) while his or her purchase right remains outstanding, then that purchase right shall immediately terminate, and all of the Participant’s payroll deductions (or other permitted form of contribution) for the Purchase Interval in which the purchase right so terminates shall be immediately refunded.

(ii) However, should the Participant cease to remain in active service by reason of an approved unpaid leave of absence, then the Participant

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shall have the right, exercisable up until the last business day of the Purchase Interval in which such leave commences, to (a) withdraw all the payroll deductions (or other permitted form of contribution) collected to date on his or her behalf for that Purchase Interval or (b) have such funds held for the purchase of shares on his or her behalf on the next scheduled Purchase Date. Unless otherwise determined by the Plan Administrator for one or more offerings, in no event, however, shall any further payroll deductions be collected on the Participant’s behalf during such leave. Upon the Participant’s return to active service (x) within three (3) months following the commencement of such leave or (y) prior to the expiration of any longer period for which such Participant has a right to reemployment with the Corporation (or an Affiliate) provided by statute or contract, his or her payroll deductions (or other permitted form of contribution) under the Plan shall automatically resume at the rate in effect at the time the leave began, unless the Participant withdraws from the Plan prior to his or her return. Unless otherwise determined by the Plan Administrator for one or more offerings, an individual who returns to active employment following a leave of absence that exceeds in duration the applicable (x) or (y) time period will be treated as a new Employee for purposes of subsequent participation in the Plan and must accordingly re-enroll in the Plan (by making a timely filing of the prescribed enrollment forms) on or before his or her scheduled Entry Date into the offering period.

I. Change in Control. Each outstanding purchase right shall automatically be exercised, immediately prior to the effective date of any Change in Control, by applying the payroll deductions of each Participant (or other permitted form of contribution) for the Purchase Interval in which such Change in Control occurs to the purchase of whole shares of Common Stock at a purchase price per share equal to eighty-five percent (85%) of the lower of (i) the Fair Market Value per share of Common Stock on the Participant’s Entry Date into the offering period in which such individual is enrolled at the time of such Change in Control or (ii) the Fair Market Value per share of Common Stock immediately prior to the effective date of such Change in Control (or such higher price in effect for the Purchase Interval). However, any applicable limitation on the number of shares of Common Stock purchasable per Participant shall continue to apply to any such purchase, but not the limitation applicable to the maximum number of shares of Common Stock purchasable in total by all Participants on any one Purchase Date.

The Corporation shall use its best efforts to provide at least ten (10) days’ prior written notice of the occurrence of any Change in Control, and the Participants shall, following the receipt of such notice, have the right to terminate their outstanding purchase rights prior to the effective date of the Change in Control.

J. Proration of Purchase Rights. Should the total number of shares of Common Stock to be purchased pursuant to outstanding purchase rights on any particular date exceed the number of shares then available for issuance under the Plan, the Plan Administrator shall make a pro-rata allocation of the available shares on a uniform and nondiscriminatory basis, and the payroll deductions (or other permitted form of contribution) of each Participant, to the extent in excess of the aggregate purchase price payable for the Common Stock pro-rated to such individual, shall be refunded.

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K. ESPP Brokerage Account. The Plan Administrator shall have the discretionary authority to require that the shares purchased on behalf of each Participant be deposited directly into a brokerage account which the Corporation shall establish for the Participant at a Corporation-designated brokerage firm. The account will be known as the ESPP Brokerage Account. Except as otherwise provided below, the deposited shares may not be transferred (either electronically or in certificate form) from the ESPP Brokerage Account until the later of the following two periods: (i) the end of the two (2)-year period measured from the Participant’s Entry Date into the offering period in which the shares were purchased and (ii) the end of the one (1)-year measured from the actual purchase date of those shares. Such limitation shall apply both to transfers to different accounts with the same ESPP broker and to transfers to other brokerage firms. Any shares held for the required holding period may be transferred (either electronically or in certificate form) to other accounts or to other brokerage firms.

The foregoing procedures shall not in any way limit when the Participant may sell his or her shares. Those procedures are designed solely to assure that any sale of shares prior to the satisfaction of the required holding period is made through the ESPP Brokerage Account. In addition, the Participant may request a stock certificate or share transfer from his or her ESPP Brokerage Account prior to the satisfaction of the required holding period should the Participant wish to make a gift of any shares held in that account. However, shares may not be transferred (either electronically or in certificate form) from the ESPP Brokerage Account for use as collateral for a loan, unless those shares have been held for the required holding period.

The foregoing procedures shall apply to all shares purchased by the Participant under the Plan, whether or not the Participant continues in Employee status.

L. Assignability. The purchase right shall be exercisable only by the Participant and shall not be assignable or transferable by the Participant.

M. Stockholder Rights. A Participant shall have no stockholder rights with respect to the shares subject to his or her outstanding purchase right until the shares are purchased on the Participant’s behalf in accordance with the provisions of the Plan and the Participant has become a holder of record of the purchased shares.

VIII. ACCRUAL LIMITATIONS

A. No Participant shall be entitled to accrue rights to acquire Common Stock pursuant to any purchase right outstanding under the Plan if and to the extent such accrual, when aggregated with (i) rights to purchase Common Stock accrued under any other purchase right granted under the Plan and (ii) similar rights accrued under other employee stock purchase plans (within the meaning of Code Section 423)) of the Corporation or any Affiliate, would otherwise permit such Participant to purchase more than Twenty-Five Thousand Dollars ($25,000.00) worth of stock of the Corporation or any Affiliate (determined on the basis of the Fair Market Value per share on the date or dates such rights are granted) for each calendar year such rights are at any time outstanding.

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B. For purposes of applying such accrual limitations to the purchase rights granted under the Plan, the following provisions shall be in effect:

(i) The right to acquire Common Stock under each outstanding purchase right shall accrue in a series of installments on each successive Purchase Date during the offering period in which such right remains outstanding.

(ii) No right to acquire Common Stock under any outstanding purchase right shall accrue to the extent the Participant has already accrued in the same calendar year the right to acquire Common Stock under one or more other purchase rights at a rate equal to Twenty-Five Thousand Dollars ($25,000.00) worth of Common Stock (determined on the basis of the Fair Market Value per share on the date or dates of grant) for each calendar year such rights were at any time outstanding.

C. If by reason of such accrual limitations, any purchase right of a Participant does not accrue for a particular Purchase Interval, then the payroll deductions (or other permitted form of contribution) that the Participant made during that Purchase Interval with respect to such purchase right shall be promptly refunded.

D. In the event there is any conflict between the provisions of this Article VIII and one or more provisions of the Plan or any instrument issued thereunder, the provisions of this Article VIII shall be controlling.

IX. EFFECTIVE DATE AND TERM OF THE PLAN

A. The Plan was adopted by the Board on October 26, 2010 and shall become effective at the Effective Time, provided no purchase rights granted under the Plan shall be exercised, and no shares of Common Stock shall be issued hereunder, until (i) the Plan shall have been approved by the stockholders of the Corporation and (ii) the Corporation shall have complied with all applicable requirements of the 1933 Act (including the registration of the shares of Common Stock issuable under the Plan on a Form S-8 registration statement filed with the Securities and Exchange Commission), all applicable listing requirements of the Stock Exchange on which the Common Stock is listed for trading and all other applicable requirements established by law or regulation. In the event such stockholder approval is not obtained, or such compliance is not effected, within twelve (12) months after the date on which the Plan is adopted by the Board, the Plan shall terminate and have no further force or effect, and all sums collected from Participants during the initial offering period hereunder shall be refunded.

B. Unless sooner terminated by the Board, the Plan shall terminate upon the earliest of (i) the last business day in February 2021, (ii) the date on which all shares available for issuance under the Plan shall have been sold pursuant to purchase rights exercised under the Plan or (iii) the date on which all purchase rights are exercised in connection with a Change in

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Control. No further purchase rights shall be granted or exercised, and no further payroll deductions (or other permitted form of contribution) shall be collected, under the Plan following such termination.

X. AMENDMENT OF THE PLAN

A. The Board may alter or amend the Plan to become effective as of the start date of the next offering period thereafter under the Plan. In addition, the Board may suspend or terminate the Plan at any time to become effective immediately following the close of any Purchase Interval.

B. In no event may the Board effect any of the following amendments or revisions to the Plan without the approval of the Corporation’s stockholders: (i) increase the number of shares of Common Stock issuable under the Plan, except for permissible adjustments in the event of certain changes in the Corporation’s capitalization or (ii) modify the eligibility requirements for participation in the Plan.

XI. GENERAL PROVISIONS

A. All costs and expenses incurred in the administration of the Plan shall be paid by the Corporation; however, each Participant shall bear all costs and expenses incurred by such individual in the sale or other disposition of any shares purchased under the Plan.

B. Nothing in the Plan shall confer upon the Participant any right to continue in the employ of the Corporation or any Affiliate for any period of specific duration or interfere with or otherwise restrict in any way the rights of the Corporation (or any Affiliate employing such person) or of the Participant, which rights are hereby expressly reserved by each, to terminate such person’s employment at any time for any reason, with or without cause.

C. The provisions of the Plan shall be governed by the laws of the State of Texas without resort to that State’s conflict-of-laws rules.

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APPENDIX

The following definitions shall be in effect under the Plan:

A. Affiliate shall mean any parent or subsidiary corporation of the Corporation (as determined in accordance with Code Section 424), whether now existing or subsequently established.

B. Board shall mean the Corporation’s Board of Directors.

C. Cash Earnings shall mean (i) the regular base salary paid to a Participant by one or more Participating Companies during such individual’s period of participation in one or more offering periods under the Plan and (ii) any overtime payments, bonuses, commissions, profit-sharing distributions and other incentive-type payments received during such period. Cash Earnings shall be calculated before deduction of (A) any income or employment tax withholdings or (B) any contributions made by Participant to any Code Section 401(k) salary deferral plan or Code Section 125 cafeteria benefit program now or hereafter established by the Corporation or any Corporate Affiliate. Cash Earnings shall not include any contributions made on the Participant’s behalf by the Corporation or any Corporate Affiliate to any employee benefit or welfare plan now or hereafter established (other than Code Section 401(k) or Code Section 125 contributions deducted from such Cash Earnings). The Plan Administrator may make modifications to the definition of Cash Earnings for one or more offerings as deemed appropriate.

D. Change in Control shall mean a change in ownership or control of the Corporation effected through any of the following transactions:

(i) a merger, consolidation or other reorganization approved by the Corporation’s stockholders, unless securities representing more than fifty percent (50%) of the total combined voting power of the voting securities of the successor company are immediately thereafter beneficially owned, directly or indirectly and in substantially the same proportion, by the persons who beneficially owned the Corporation’s outstanding voting securities immediately prior to such transaction,

(ii) a sale, transfer or other disposition of all or substantially all of the Corporation’s assets in liquidation or dissolution of the Corporation,

(iii) the acquisition, directly or indirectly by any person or related group of persons (other than the Corporation or a person that directly or indirectly controls, is controlled by, or is under common control with, the Corporation), of beneficial ownership (within the meaning of Rule 13d-3 of the 1934 Act) of securities possessing more than fifty percent (50%) of the total combined voting power of the Corporation’s outstanding securities pursuant to a tender or exchange offer made directly to the Corporation’s stockholders, or

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(iv) a change in the composition of the Board over a period of twelve (12) consecutive months or less such that a majority of the Board members ceases, by reason of one or more contested elections for Board membership, to be comprised of individuals who either (A) have been Board members continuously since the beginning of such period or (B) have been elected or nominated for election as Board members during such period by at least a majority of the Board members described in clause (A) who were still in office at the time the Board approved such election or nomination.

E. Code shall mean the Internal Revenue Code of 1986, as amended.

F. Common Stock shall mean the Corporation’s common stock.

G. Corporation shall mean Masergy Communications, Inc., a Delaware corporation, and any corporate successor to all or substantially all of the assets or voting stock of Masergy Communications, Inc. that shall by appropriate action adopt the Plan.

H. Effective Time shall mean the time at which the Underwriting Agreement is executed and the Common Stock priced for the initial public offering of such Common Stock.

I. Eligible Employee shall mean any Employee who is employed by a Participating Company on a basis under which he or she is regularly expected to render more than twenty (20) hours of service per week for more than five (5) months per calendar year for earnings considered wages under Code Section 3401(a).

J. Employee shall mean an individual who is in the employ of the Corporation (or any Affiliate), subject to the control and direction of the employer entity as to both the work to be performed and the manner and method of performance.

K. Entry Date shall mean the date an Eligible Employee first commences participation in the offering period in effect under the Plan. The earliest Entry Date under the Plan shall be the Effective Time.

L. Fair Market Value per share of Common Stock on any relevant date shall be the closing selling price per share of Common Stock at the close of regular hours trading (i.e., before after-hours trading begins) on the date in question on the Stock Exchange serving as the primary market for the Common Stock, as such price is reported by the National Association of Securities Dealers (if primarily traded on the Nasdaq Global or Global Select Market) or as officially quoted in the composite tape of transactions on any other Stock Exchange on which the Common Stock is then primarily traded. If there is no closing selling price for the Common Stock on the date in question, then the Fair Market Value shall be the closing selling price on the last preceding date for which such quotation exists. However, for the initial offering period beginning at the Effective Time, the Fair Market Value shall be deemed to be equal to the price per share at which the Common Stock is sold in the initial public offering pursuant to the Underwriting Agreement.

M. 1933 Act shall mean the Securities Act of 1933, as amended.

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N. Participant shall mean any Eligible Employee of a Participating Corporation who is actively participating in the Plan.

O. Participating Corporation shall mean the Corporation and such Affiliate or Affiliates as may be authorized from time to time by the Board to extend the benefits of the Plan to their Eligible Employees.

P. Plan shall mean the Corporation’s Employee Stock Purchase Plan, as set forth in this document.

Q. Plan Administrator shall mean the committee of two (2) or more Board members appointed by the Board to administer the Plan.

R. Purchase Date shall mean the last business day of each Purchase Interval.

S. Purchase Interval shall mean each purchase interval within a particular offering period (as determined by the Plan Administrator) at the end of which there shall be purchased shares of Common Stock on behalf of each Participant.

T. Stock Exchange shall mean the American Stock Exchange, the Nasdaq Global or Global Select Market or the New York Stock Exchange.

U. Underwriting Agreement shall mean the agreement between the Corporation and the underwriter or underwriters managing the initial public offering of the Common Stock.

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