MAVENIR SYSTEMS, INC. NOTICE OF GRANT OF STOCK OPTION

Exhibit 10.8

EARLY EXERCISE

MAVENIR SYSTEMS, INC.

NOTICE OF GRANT OF STOCK OPTION

Notice is hereby given of the following option grant (the “Option”) to purchase shares (the “Option Shares”) of the Common Stock of Mavenir Systems, Inc., a Delaware corporation (the “Company”):

Optionee:                                                                                       

Grant Date:                                                                                  

Vesting Commencement Date:                                                    

Exercise Price: $                                         per share

Number of Option Shares:                      shares of Common Stock

Expiration Date:                                                                          

Type of Option:              Incentive Stock Option

                     Non-Qualified Stock Option

Date Exercisable: Immediately Exercisable for exempt employees. The Option shall become exercisable for all the Option Shares upon the Optionee’s completion of six (6) months of Service measured from the Grant Date for non-exempt employees.

Vesting Schedule: This Option shall become vested and exercisable with respect to (i) one fourth (1/4^th) of the Option Shares on the first anniversary of the Vesting Commencement Date and (ii) an additional one forty-eighth (1/48^th) of the Option Shares on the corresponding day of each calendar month thereafter or, if such calendar month does not have the corresponding day, on the last day of such calendar month. In no event shall this Option vest or become exercisable for any additional Option Shares following Optionee’s cessation of Service, except to the extent (if any) specifically authorized by the Plan Administrator in its sole discretion pursuant to a written agreement with Optionee.

Optionee understands and agrees that the Option is granted subject to and in accordance with the terms of the Mavenir Systems, Inc. 2013 Equity Incentive Plan (the “Plan”). Optionee further agrees to be bound by the terms of the Plan and the terms of the Option as set forth in the Stock Option Agreement attached hereto as Exhibit A. Optionee hereby acknowledges receipt of a copy of the Plan in the form attached hereto as Exhibit B.

TRANSFER RESTRICTIONS. OPTIONEE HEREBY AGREES THAT ALL UNVESTED OPTION SHARES ACQUIRED UPON THE EXERCISE OF THE OPTION SHALL BE SUBJECT TO CERTAIN REPURCHASE RIGHTS EXERCISABLE BY THE COMPANY AND ITS ASSIGNS. THE TERMS OF SUCH RIGHTS ARE SPECIFIED IN THE STOCK PURCHASE AGREEMENT ATTACHED HERETO AS EXHIBIT C.

At Will Employment. Nothing in this Notice or in the attached Stock Option Agreement or Plan shall confer upon Optionee any right to continue in Service for any period of specific duration or interfere with or otherwise restrict in any way the rights of the Company (or any Affiliate employing or retaining Optionee) or of Optionee, which rights are hereby expressly reserved by each, to terminate Optionee’s Service at any time for any reason, with or without cause.

Definitions. All capitalized terms in this Notice shall have the meaning assigned to them in this Notice, in the attached Stock Option Agreement or in the Plan.

Attachments:

Exhibit A – Stock Option Agreement

Exhibit B – 2013 Equity Incentive Plan

Exhibit C – Stock Purchase Agreement

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EXHIBIT A

STOCK OPTION AGREEMENT

MAVENIR SYSTEMS, INC.

STOCK OPTION AGREEMENT

RECITALS

A. The Board has adopted the 2013 Equity Incentive Plan (the “Plan”) for the purpose of retaining the services of selected Employees, Directors and Consultants in the service of the Company (or any Affiliate).

B. Optionee is to render valuable services to the Company (or an Affiliate), and this Agreement is executed pursuant to, and is intended to carry out the purposes of, the Plan in connection with the Company’s grant of an option to Optionee.

C. All capitalized terms in this Agreement not defined herein shall have the meaning assigned to them in the Grant Notice (as defined below) or in the Plan.

NOW, THEREFORE, it is hereby agreed as follows:

1. Grant of Option. The Company hereby grants to Optionee, as of the Grant Date as specified in the Notice of Grant of Stock Option accompanying this Agreement, pursuant to which Optionee has been informed of the basic terms of the option evidenced hereby (the “Grant Notice”), an option to purchase up to the number of Option Shares specified in the Grant Notice. The Option Shares shall be purchasable from time to time during the option term specified in Section 2 at the Exercise Price.

2. Option Term. This Option shall have a term of ten (10) years measured from the Grant Date and shall accordingly expire at the close of business on the date on which the option expires as specified in the Grant Notice (the “Expiration Date”), unless sooner terminated in accordance with Sections 5 or 6.

3. Limited Transferability.

(a) This Option shall be neither transferable nor assignable by Optionee other than by will or the laws of inheritance following Optionee’s death and may be exercised, during Optionee’s lifetime, only by Optionee. However, Optionee may designate one or more persons as the beneficiary or beneficiaries of this Option, and this Option shall, in accordance with such designation, automatically be transferred to such beneficiary or beneficiaries upon Optionee’s death while holding this Option. Such beneficiary or beneficiaries shall take the transferred option subject to all the terms and conditions of this Agreement, including (without limitation) the limited time period during which this Option may, pursuant to Section 5, be exercised following Optionee’s death.

(b) If this Option is designated a Non-Qualified Stock Option in the Grant Notice, then this Option may be assigned in whole or in part during Optionee’s lifetime to one or more of Optionee’s Family Members or to a trust established for the exclusive benefit of Optionee and/or one or more such Family Members, to the extent such assignment is in

Exhibit A to Notice of Grant of Stock Option (Early Exercise)

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connection with the Optionee’s estate plan or pursuant to a domestic relations order. The assigned portion shall be exercisable only by the person or persons who acquire a proprietary interest in the option pursuant to such assignment. The terms applicable to the assigned portion shall be the same as those in effect for this Option immediately prior to such assignment.

4. Dates of Exercise. This Option shall vest for the Option Shares in one or more installments as specified in the Grant Notice. As the Option becomes unvested for such installments, those installments shall accumulate, and the Option shall remain exercisable for the accumulated installments until the Expiration Date or sooner termination of the Option term under Sections 5 or 6.

5. Cessation of Service. The option term specified in Section 2 shall terminate (and this Option shall cease to be outstanding) prior to the Expiration Date should any of the following provisions become applicable:

(a) Should Optionee cease to remain in Service for any reason (other than death, Permanent Disability or Cause) while this Option is outstanding, then Optionee (or any person or persons to whom this Option is transferred pursuant to a permitted transfer under Section 3) shall have a period of three (3) months (commencing with the date of such cessation of Service) during which to exercise this Option, but in no event shall this Option be exercisable at any time after the Expiration Date.

(b) Should Optionee die while this Option is outstanding, then the personal representative of Optionee’s estate or the person or persons to whom the option is transferred pursuant to Optionee’s will or the laws of inheritance following Optionee’s death or, if applicable, the person to whom the option is transferred during Optionee’s lifetime pursuant to a permitted transfer under Section 3 shall have the right to exercise this Option. However, if Optionee dies while holding this Option and has an effective beneficiary designation in effect for this Option at the time of his or her death, then the designated beneficiary or beneficiaries shall have the exclusive right to exercise this Option following Optionee’s death. Any such right to exercise this Option shall lapse, and this Option shall cease to be outstanding, upon the earlier of (i) the expiration of the twelve (12)-month period measured from the date of Optionee’s death or (ii) the Expiration Date.

(c) Should Optionee cease Service by reason of Permanent Disability while this Option is outstanding, then Optionee (or any person or persons to whom this Option is transferred pursuant to a permitted transfer under Section 3) shall have a period of twelve (12) months (commencing with the date of such cessation of Service) during which to exercise this Option. In no event shall this Option be exercisable at any time after the Expiration Date.

(d) During the limited period of post-Service exercisability, this Option may not be exercised in the aggregate for more than the number of Option Shares in which Optionee is, at the time of Optionee’s cessation of Service, vested pursuant to the Vesting Schedule specified in the Grant Notice or the special vesting acceleration provisions of Section 6. No additional Option Shares shall vest, whether pursuant to the normal Vesting Schedule specified in the Grant Notice or the special vesting acceleration provisions of Section 6, following

Exhibit A to Notice of Grant of Stock Option (Early Exercise)

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Optionee’s cessation of Service, except to the extent (if any) specifically authorized by the Plan Administrator pursuant to an express written agreement with Optionee. Upon the expiration of such limited exercise period or (if earlier) upon the Expiration Date, this Option shall terminate and cease to be outstanding for any vested Option Shares for which the option has not been exercised.

(e) Should Optionee’s Service be terminated for Cause or should Optionee otherwise engage in conduct constituting grounds for a termination for Cause while this Option is outstanding, then this Option shall terminate immediately and cease to remain outstanding.

6. Change of Control.

(a) Should a Change of Control occur during Optionee’s period of Service, then the Option Shares at the time subject to this Option but not otherwise vested shall automatically vest in full so that this Option shall, immediately prior to the effective date of the Change of Control, become exercisable for all of the Option Shares as fully vested shares and may be exercised for any or all of those Option Shares as vested shares. However, the Option Shares shall not vest on such an accelerated basis if and to the extent: (i) this Option is assumed or substituted with an equivalent award by the successor corporation (or parent thereof) or otherwise continued in full force and effect pursuant to the terms of the Change of Control transaction and the Company’s repurchase rights with respect to the unvested Option Shares purchasable under this Option are assigned to such successor corporation (or parent thereof) or otherwise continued in effect or (ii) this Option is to be replaced with a cash retention program of the successor corporation which preserves the spread existing on the unvested Option Shares at the time of the Change of Control (the excess of the Fair Market Value of those Option Shares over the Exercise Price payable for such shares) and provides for subsequent payout of that spread in accordance with the same Vesting Schedule applicable to those unvested Option Shares as set forth in the Grant Notice or (iii) such accelerated vesting is otherwise precluded pursuant to the provisions of Paragraph 5(d) above. Notwithstanding the foregoing, no such cash retention program shall be established for this Option (or any other option granted to Optionee under the Plan) to the extent such program would otherwise be deemed to constitute a deferred compensation arrangement subject to the requirements of Code Section 409A and the Treasury Regulations thereunder.

(b) Immediately following the Change of Control, this Option shall terminate and cease to be outstanding, except to the extent assumed by the successor corporation (or parent thereof) or otherwise continued in full force and effect pursuant to the terms of the Change of Control transaction.

(c) If this Option is assumed in connection with a Change of Control or otherwise continued in effect, then this option shall be appropriately adjusted, immediately after such Change of Control, to apply to the number and class of securities which would have been issuable to Optionee in consummation of such Change of Control had the Option been exercised immediately prior to such Change of Control, and appropriate adjustments shall also be made to the Exercise Price, provided the aggregate Exercise Price shall remain the same. To the extent that the actual holders of the Company’s outstanding Common Stock receive cash consideration

Exhibit A to Notice of Grant of Stock Option (Early Exercise)

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for their Common Stock in consummation of the Change of Control, the successor corporation may, in connection with the assumption or continuation of this option, substitute one or more shares of its own common stock with a fair market value equivalent to the cash consideration paid per share of Common Stock in such Change of Control provided such common stock is readily traded on an established U.S. securities exchange or market.

(d) This Agreement shall not in any way affect the right of the Company to adjust, reclassify, reorganize or otherwise change its capital or business structure or to merge, consolidate, dissolve, liquidate or sell or transfer all or any part of its business or assets.

7. Adjustment in Option Shares. 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 or other change affecting the outstanding Common Stock as a class without the Company’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 extraordinary dividend or distribution, then equitable adjustments shall be made to (i) the total number and/or class of securities subject to this Option and (ii) the Exercise Price. The adjustments shall be made by the Plan Administrator in such manner as the Plan Administrator deems appropriate in order to reflect such change, and those adjustments shall be final, binding and conclusive.

8. Stockholder Rights. The holder of this Option shall not have any stockholder rights with respect to the Option Shares until such person shall have exercised the Option, paid the Exercise Price and become the record holder of the purchased shares.

9. Manner of Exercising Option.

(a) In order to exercise this Option with respect to all or any part of the Option Shares for which this Option is at the time exercisable, Optionee (or any other person or persons exercising this Option) must take the following actions:

(i) Execute and deliver to the Company a stock purchase agreement substantially in the form of Exhibit C to the Grant Notice (the “Purchase Agreement”) for the Option Shares for which the option is exercised or comply with such other procedures as the Company may establish for notifying the Company of the exercise of this Option.

(ii) Pay the aggregate Exercise Price for the purchased shares in one or more of the following forms:

(A) cash or certified check made payable to the Company; or

(B) at the discretion of the Plan Administrator and to the extent permitted by Applicable Law, in shares of Common Stock valued at Fair Market Value on the date on which this Option shall have been exercised in accordance with this Section 9 (the “Exercise Date”) and held by Optionee (or any other person or persons exercising the Option) for the requisite period (if any) necessary to avoid a charge to the Company’s earnings for financial reporting purposes; or

Exhibit A to Notice of Grant of Stock Option (Early Exercise)

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(C) to the extent the option is exercised for vested Option Shares following the IPO, through a special sale and remittance procedure established by the Company pursuant to which Optionee (or any other person or persons exercising the option) shall concurrently provide irrevocable instructions (1) to a brokerage firm (reasonably satisfactory to the Company for purposes of administering such procedure in compliance with any applicable pre-clearance or pre-notification requirements) to effect the immediate sale of the purchased shares and remit to the Company, out of the sale proceeds available on the settlement date, sufficient funds to cover the aggregate Exercise Price payable for the purchased shares plus all applicable income and employment taxes required to be withheld by the Company by reason of such exercise and (2) to the Company to deliver the certificates for the purchased shares directly to such brokerage firm on such settlement date in order to complete the sale; or

(D) such other method of payment as the Plan Administrator may approve.

(iii) Furnish to the Company appropriate documentation that the person or persons exercising the option (if other than Optionee) have the right to exercise this Option.

(iv) Execute and deliver to the Company such written representations as may be requested by the Company in order for it to comply with the applicable requirements of applicable securities laws.

(v) Make appropriate arrangements with the Company (or Affiliate employing or retaining Optionee) for the satisfaction of all applicable income and employment tax withholding requirements applicable to the option exercise.

(b) As soon as practical after the Exercise Date, the Company shall issue to or on behalf of Optionee (or any other person or persons exercising this Option) a certificate for the purchased Option Shares, with the appropriate legends affixed thereto.

(c) In no event may this Option be exercised for any fractional shares.

10. REPURCHASE RIGHTS. ALL UNVESTED OPTION SHARES ACQUIRED UPON THE EXERCISE OF THIS OPTION SHALL BE SUBJECT TO CERTAIN RIGHTS OF THE COMPANY AND ITS ASSIGNS TO REPURCHASE THOSE SHARES IN ACCORDANCE WITH THE TERMS SPECIFIED IN THE PURCHASE AGREEMENT.

Exhibit A to Notice of Grant of Stock Option (Early Exercise)

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11. Compliance with Laws and Regulations.

(a) The exercise of this Option and the issuance of the Option Shares upon such exercise shall be subject to compliance by the Company and Optionee with all applicable requirements of law relating thereto and with all applicable regulations of any stock exchange on which the Common Stock may be listed for trading at the time of such exercise and issuance.

(b) The inability of the Company to obtain approval from any regulatory body having authority deemed by the Company to be necessary to the lawful issuance and sale of any Common Stock pursuant to this Option shall relieve the Company of any liability with respect to the non-issuance or sale of the Common Stock as to which such approval shall not have been obtained. The Company, however, shall use its best efforts to obtain all such approvals.

12. Successors and Assigns. Except to the extent otherwise provided in Sections 3 and 5, the provisions of this Agreement shall inure to the benefit of, and be binding upon, the Company and its successors and assigns and Optionee, Optionee’s assigns and the legal representatives, heirs and legatees of Optionee’s estate.

13. Notices. Any notice required to be given or delivered to the Company under the terms of this Agreement shall be in writing and addressed to the Company at its principal corporate offices. Any notice required to be given or delivered to Optionee shall be in writing and addressed to Optionee at the address indicated below Optionee’s signature line on the Grant Notice. All notices shall be deemed effective upon personal delivery or upon deposit in the U.S. mail, postage prepaid and properly addressed to the party to be notified.

Optionee generally consents to the delivery of any notice pursuant to the Delaware General Corporation Law (the “DGCL”), as amended or superseded from time to time, by electronic transmission pursuant to Section 232 of the DGCL (“Electronic Notice”) at the electronic mail address or the facsimile number as set forth in the books of the Company. To the extent that any notice given via electronic transmission is returned or undeliverable for any reason, the foregoing consent shall be deemed to have been revoked until a new or corrected electronic mail address has been provided, and such attempted Electronic Notice shall be ineffective and deemed to not have been given. Optionee agrees to promptly notify the Company of any change in Optionee’s electronic mail address, but failure to do so shall not affect the foregoing.

14. Construction; Administrator Discretions. This Agreement and the Option evidenced hereby are made and granted pursuant to the Plan and are in all respects limited by and subject to the terms of the Plan. All decisions of the Plan Administrator with respect to any question or issue arising under the Plan or this Agreement shall be conclusive and binding on all persons having an interest in this Option.

15. Electronic Delivery. The Company may, in its sole discretion, decide to deliver any documents related to options awarded under the Plan or future options that may be awarded under the Plan by electronic means or request Optionee’s consent to participate in the Plan by electronic means. Optionee hereby consents to receive such documents by electronic delivery and agrees to participate in the Plan through any on-line or electronic system established and maintained by the Company or another third party designated by the Company.

Exhibit A to Notice of Grant of Stock Option (Early Exercise)

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16. Governing Law. The interpretation, performance and enforcement of this Agreement shall be governed by the laws of the State of Texas without resort to that state’s conflict-of-laws rules.

17. Stockholder Approval. If the Option Shares covered by this Agreement exceed, as of the Grant Date, the number of shares of Common Stock which may be issued under the Plan as last approved by the Company’s stockholders, then this Option shall be void with respect to such excess shares, unless stockholder approval of an amendment sufficiently increasing the number of shares of Common Stock issuable under the Plan is obtained in accordance with the provisions of the Plan.

18. Code Section 409A. Under Section 409A of the Code, an option that is granted with an exercise price per share of Common Stock that is determined by the Internal Revenue Service (the “IRS”) to be less than the Fair Market Value of a share of Common Stock on the Grant Date (a “Discount Option”) may be considered “deferred compensation.” A Discount Option may result in (i) income recognition by Optionee prior to the exercise of the option, (ii) an additional twenty percent (20%) federal income tax, and (iii) potential penalty and interest charges. The Discount Option may also result in additional state income, penalty and interest tax to the Optionee. Optionee acknowledges that the Company cannot and has not guaranteed that the IRS will agree that the exercise price per share of Common Stock of this Option equals or exceeds the Fair Market Value of a share of Common Stock on the Grant Date in a later examination. Optionee agrees that if the IRS determines that this Option was granted with an exercise price per share of Common Stock that was less than the Fair Market Value of a share of Common Stock on the Grant Date, Optionee will be solely responsible for Optionee’s costs related to such a determination.

19. Modifications to the Agreement. This Agreement and the Plan constitutes the entire understanding of the parties on the subjects covered. Optionee expressly warrants that he or she is not accepting this Agreement in reliance on any promises, representations, or inducements other than those contained herein. Modifications to the option, this Agreement or the Plan can be made only in an express written contract executed by a duly authorized officer of the Company. Notwithstanding anything to the contrary in the Plan or this Agreement, the Company reserves the right to revise this Agreement as it deems necessary or advisable, in its sole discretion and without the consent of Optionee, to comply with Section 409A of the Code or to otherwise avoid imposition of any additional tax or income recognition under Section 409A of the Code in connection to this Option.

20. Additional Terms Applicable to an Incentive Stock Option. In the event this Option is designated an Incentive Option in the Grant Notice, the following terms and conditions shall also apply to the grant:

(a) This Option shall cease to qualify for favorable tax treatment as an Incentive Stock Option if (and to the extent) this Option is exercised for one or more Option Shares (i) more than three (3) months after the date Optionee ceases to be an Employee for any reason other than death or Permanent Disability laws; or (ii) more than twelve (12) months after the date Optionee ceases to be an Employee by reason of Permanent Disability.

Exhibit A to Notice of Grant of Stock Option (Early Exercise)

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(b) This Option shall not become exercisable in the calendar year in which granted if (and to the extent) the aggregate Fair Market Value (determined at the Grant Date) of the Common Stock for which this Option would otherwise first become exercisable in such calendar year would, when added to the aggregate value (determined as of the respective date or dates of grant) of the Common Stock and any other securities for which one or more other Incentive Options granted to Optionee prior to the Grant Date (whether under the Plan or any other option plan of the Company or any Affiliate) first become exercisable during the same calendar year, exceed One Hundred Thousand Dollars ($100,000) in the aggregate. To the extent the exercisability of this Option is deferred by reason of the foregoing limitation, the deferred portion shall become exercisable in the first calendar year or years thereafter in which the One Hundred Thousand Dollar ($100,000) limitation of this Section 20(a) would not be contravened, but such deferral shall in all events end immediately prior to the effective date of a Change of Control in which this Option is not to be assumed or otherwise continued in effect, whereupon the option shall become immediately exercisable as a Non-Qualified Stock Option for the deferred portion of the Option Shares.

(c) Should Optionee hold, in addition to this Option, one or more other options to purchase Common Stock which become exercisable for the first time in the same calendar year as this Option, then for purposes of the foregoing limitations on the exercisability of such options as Incentive Stock Options, this Option and each of those other options shall be deemed to become first exercisable in that calendar year on the basis of the chronological order in which they were granted, except to the extent otherwise provided under applicable law or regulation.

21. Market Standoff Agreement. Optionee hereby agrees that, if requested by the managing underwriter, it will not, without the prior written consent of the Company, during the period commencing on the date of the final prospectus relating to the Company’s initial public offering or any secondary public offering, as applicable, and ending on the date specified by the Company and the managing underwriter (such period not to exceed one hundred eighty (180) calendar days in the case of an initial public offering and, solely in the case of a holder of shares of the Company’s Common Stock, ninety (90) calendar days in the case of any secondary public offering (or such other period as may be requested by the Company or managing underwriter to accommodate regulatory restrictions on (i) the publication or other distribution of research reports and (ii) analyst recommendations and opinions, including, but not limited to, the restrictions contained in FINRA Rule 2711(f)(4) or NYSE Rule 472(f)(4), or any successor provisions or amendments thereto)) (i) lend, offer, pledge, sell, contract to sell, sell any option or contract to purchase, purchase any option or contract to sell, grant any option, right or warrant to purchase, or otherwise transfer or dispose of, directly or indirectly, any securities of the Company, including (without limitation) shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock (whether now owned or hereafter acquired) or (ii) enter into any swap or other arrangement that transfers to another, in whole or in part, any of the economic consequences of ownership of any securities of the Company,

Exhibit A to Notice of Grant of Stock Option (Early Exercise)

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including (without limitation) shares of Common Stock or any securities convertible into or exercisable or exchangeable for Common Stock (whether now owned or hereafter acquired), whether any such transaction described in clause (i) or (ii) above is to be settled by delivery of securities, in cash or otherwise. Optionee agrees that any transferee of the Option or shares acquired pursuant to the Option shall be bound by this Section 21.

Exhibit A to Notice of Grant of Stock Option (Early Exercise)

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EXHIBIT B

2013 EQUITY INCENTIVE PLAN

EXHIBIT C

STOCK PURCHASE AGREEMENT

EARLY EXERCISE

MAVENIR SYSTEMS, INC.

STOCK PURCHASE AGREEMENT

AGREEMENT made this _____ day of ___________________, 20___ by and between Mavenir Systems, Inc., a Delaware corporation, and ________________________, Optionee under the Company’s 2013 Equity Incentive Plan.

All capitalized terms in this Agreement shall have the meaning assigned to them in this Agreement, in the Notice of Grant of Stock Option to which this Agreement relates or in the Plan attached as Exhibit B to the Notice of Grant to which this Agreement relates.

A. Exercise of Option

1. Exercise. Optionee hereby purchases _______ shares of Common Stock (the “Purchased Shares”) pursuant to that certain option (the “Option”) granted Optionee on ____________________, _____ (the “Grant Date”) to purchase up to _________ shares of Common Stock (the “Option Shares”) under the Plan at the exercise price of $ ___________ per share (the “Exercise Price”).

2. Payment. Concurrently with the delivery of this Agreement to the Company, Optionee shall pay the Exercise Price for the Purchased Shares in accordance with the provisions of all agreements and other documents evidencing the Option (the “Option Agreement”) and shall deliver whatever additional documents may be required by the Option Agreement as a condition for exercise, together with a duly-executed blank Assignment Separate from Certificate (in the form attached hereto as Exhibit I) with respect to the Purchased Shares.

3. Stockholder Rights. Until such time as the Company exercises the Repurchase Right, Optionee (or any successor in interest) shall have all the rights of a stockholder (including voting, dividend and liquidation rights) with respect to the Purchased Shares, subject, however, to the transfer restrictions of Articles B and C.

4. Information. Optionee believes Optionee has received all the information Optionee considers necessary or appropriate for deciding whether to purchase the Purchased Shares. Optionee further represents that Optionee has had an opportunity to ask questions and receive answers from the Company regarding the terms and conditions of the offering of the Purchased Shares and the business, properties, prospects and financial condition of the Company.

B. Transfer Restrictions

1. Restriction on Transfer. Except for any Permitted Transfer, Optionee shall not transfer, assign, encumber or otherwise dispose of any of the Purchased Shares which are subject to the Repurchase Right. In addition, Purchased Shares which are released from the Repurchase Right shall not be transferred, assigned, encumbered or otherwise disposed of in contravention of the Right of First Refusal under Article D (the “First Refusal Right”).

Exhibit C to Notice of Grant of Stock Option (Early Exercise)

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2. Transferee Obligations. Each person (other than the Company) to whom the Purchased Shares are transferred by means of a Permitted Transfer must, as a condition precedent to the validity of such transfer, acknowledge in writing to the Company that such person is bound by the provisions of this Agreement and that the transferred shares are subject to (i) the Repurchase Right, and (ii) the First Refusal Right, to the same extent such shares would be so subject if retained by Optionee.

3. Restrictive Legends.

(a) Legends. Optionee understands and agrees that the Company may cause the legends set forth below or legends substantially equivalent thereto, to be placed upon any certificate(s) evidencing ownership of the Shares together with any other legends that may be required by the Company or by state or federal securities laws:

THE SHARES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR THE SECURITIES LAWS OF ANY STATE, AND MAY NOT BE SOLD, TRANSFERRED, ASSIGNED, PLEDGED OR HYPOTHECATED UNLESS AND UNTIL REGISTERED UNDER SUCH ACT AND/OR APPLICABLE STATE SECURITIES LAWS, OR UNLESS, IN THE OPINION OF COUNSEL (WHICH MAY BE COUNSEL TO THE COMPANY) SATISFACTORY TO THE COMPANY, SUCH REGISTRATION IS NOT REQUIRED.

THE SHARES REPRESENTED BY THIS CERTIFICATE ARE SUBJECT TO CERTAIN RESTRICTIONS ON TRANSFER, INCLUDING A 180-DAY MARKET STANDOFF AGREEMENT, REPURCHASE RIGHTS AND RIGHTS OF FIRST REFUSAL GRANTED TO THE COMPANY AND ACCORDINGLY MAY NOT BE SOLD, ASSIGNED, TRANSFERRED, ENCUMBERED, OR IN ANY MANNER DISPOSED OF EXCEPT IN CONFORMITY WITH THE TERMS OF A STOCK PURCHASE AGREEMENT BETWEEN THE COMPANY AND THE REGISTERED HOLDER OF THE SHARES (OR THE PREDECESSOR IN INTEREST TO THE SHARES). A COPY OF SUCH AGREEMENT IS MAINTAINED AT THE COMPANY’S PRINCIPAL CORPORATE OFFICES.

(b) Stop-Transfer Notices. Optionee agrees that, in order to ensure compliance with the restrictions referred to herein, the Company may issue appropriate “stop transfer” instructions to its transfer agent, if any, and that, if the Company transfers its own securities, it may make appropriate notations to the same effect in its own records.

(c) Refusal to Transfer. The Company shall not be required (i) to transfer on its books any Shares that have been sold or otherwise transferred in violation of any of the provisions of this Exercise Notice or (ii) to treat as owner of such Shares or to accord the right to vote or pay dividends to any purchaser or other transferee to whom such Shares shall have been so transferred.

Exhibit C to Notice of Grant of Stock Option (Early Exercise)

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C. Repurchase Right

1. Grant. The Company is hereby granted the right (the “Repurchase Right”), exercisable at any time during the ninety (90)-day period following the date Optionee ceases for any reason to remain in Service or (if later) during the ninety (90)-day period following the execution date of this Agreement, to repurchase at the lower of (i) the Exercise Price or (ii) the Fair Market Value per share of Common Stock on the date of Optionee’s cessation of Service (the “Repurchase Price”) any or all of the Purchased Shares in which Optionee is not, at the time of his or her cessation of Service, vested in accordance with the Vesting Schedule applicable to those shares as specified in the Grant Notice or the special vesting acceleration provisions of Paragraph B.3.6 of this Agreement (such shares to be hereinafter referred to as the “Unvested Shares”).

2. Exercise of the Repurchase Right. The Repurchase Right shall be exercisable by written notice delivered to each Owner of the Unvested Shares prior to the expiration of the ninety (90)-day exercise period. The notice shall indicate the number of Unvested Shares to be repurchased, the Repurchase Price to be paid per share and the date on which the repurchase is to be effected, such date to be not more than thirty (30) days after the date of such notice. The certificates representing the Unvested Shares to be repurchased shall be delivered to the Company on the closing date specified for the repurchase. Concurrently with the receipt of such stock certificates, the Company shall pay to Owner, in cash or cash equivalents (including the cancellation of any purchase-money indebtedness), an amount equal to the Repurchase Price for the Unvested Shares which are to be repurchased from Owner.

3. Termination of the Repurchase Right. The Repurchase Right shall terminate with respect to any Unvested Shares for which it is not timely exercised under Section B.3.2. In addition, the Repurchase Right shall terminate and cease to be exercisable with respect to any and all Purchased Shares in which Optionee vests in accordance with the Vesting Schedule. All Purchased Shares as to which the Repurchase Right lapses shall, however, remain subject to the First Refusal Right.

4. Aggregate Vesting Limitation. If the Option is exercised in more than one increment so that Optionee is a party to one or more other Stock Purchase Agreements (the “Prior Purchase Agreements”) which are executed prior to the date of this Agreement, then the total number of Purchased Shares as to which Optionee shall be deemed to have a fully-vested interest under this Agreement and all Prior Purchase Agreements shall not exceed in the aggregate the number of Purchased Shares in which Optionee would otherwise at the time be vested, in accordance with the Vesting Schedule, had all the Purchased Shares (including those acquired under the Prior Purchase Agreements) been acquired exclusively under this Agreement.

5. Recapitalization. Any new, substituted or additional securities or other property (including cash paid other than as a regular cash dividend) which is by reason of any Recapitalization distributed with respect to the Purchased Shares shall be immediately subject to the Repurchase Right and any escrow requirements hereunder, but only to the extent the Purchased Shares are at the time covered by such right or escrow requirements. Appropriate adjustments to reflect such distribution shall be made to the number and/or class of Purchased Shares subject to this Agreement and to the Repurchase Price per share to be paid upon the exercise of the Repurchase Right in order to reflect the effect of any such Recapitalization upon the Company’s capital structure; provided, however, that the aggregate Repurchase Price shall remain the same.

Exhibit C to Notice of Grant of Stock Option (Early Exercise)

Page 3

6. Change of Control.

(a) The Repurchase Right shall automatically terminate in its entirety, and all the Purchased Shares shall vest in full, immediately prior to the consummation of any Change of Control, except to the extent the Repurchase Right is to be assigned to the successor entity in such Change of Control or otherwise continued in full force and effect pursuant to the terms of the Change of Control transaction.

(b) To the extent the Repurchase Right remains in effect following a Change of Control, such right shall apply to any new securities or other property (including any cash payments) received in exchange for the Purchased Shares in consummation of the Change of Control, but only to the extent the Purchased Shares are at the time covered by such right. Appropriate adjustments shall be made to the Repurchase Price per share payable upon exercise of the Repurchase Right to reflect the effect (if any) of the Change of Control; provided, however, that the aggregate Repurchase Price shall remain the same. The new securities or other property (including any cash payments) issued or distributed with respect to the Purchased Shares in consummation of the Change of Control shall be immediately deposited in escrow with the Company (or the successor entity) and shall not be released from escrow until Optionee vests in such securities or other property in accordance with the same Vesting Schedule in effect for the Purchased Shares.

D. Company’s Right of First Refusal. Before any Shares held by Optionee or any transferee (either being sometimes referred to herein as the “Holder”) may be sold or otherwise transferred (including transfer by gift or operation of law), the Company or its assignee(s) shall have a right of first refusal to purchase the Shares on the terms and conditions set forth in this Section (the “Right of First Refusal”).

1. Notice of Proposed Transfer. The Holder of the Shares shall deliver to the Company a written notice (the “Notice”) stating: (i) the Holder’s bona fide intention to sell or otherwise transfer such Shares; (ii) the name of each proposed purchaser or other transferee (“Proposed Transferee”); (iii) the number of Shares to be transferred to each Proposed Transferee; and (iv) the bona fide cash price or other consideration for which the Holder proposes to transfer the Shares (the “Offered Price”), and the Holder shall offer the Shares at the Offered Price to the Company or its assignee(s).

2. Exercise of Right of First Refusal. At any time within thirty (30) days after receipt of the Notice, the Company and/or its assignee(s) may, by giving written notice to the Holder, elect to purchase up to all of the Shares proposed to be transferred to any one or more of the Proposed Transferees, at the purchase price determined in accordance with subsection (c) below.

3. Purchase Price. The purchase price (“Purchase Price”) for the Shares purchased by the Company or its assignee(s) under this Section shall be the Offered Price. If the Offered Price includes consideration other than cash, the cash equivalent value of the non-cash consideration shall be determined by the Board of Directors of the Company in good faith.

Exhibit C to Notice of Grant of Stock Option (Early Exercise)

Page 4

4. Payment. Payment of the Purchase Price shall be made, at the option of the Company or its assignee(s), in cash (by check), by cancellation of all or a portion of any outstanding indebtedness of the Holder to the Company (or, in the case of repurchase by an assignee, to the assignee), or by any combination thereof within 30 days after receipt of the Notice or in the manner and at the times set forth in the Notice.

5. Holder’s Right to Transfer. To the extent that the Shares proposed in the Notice to be transferred to a given Proposed Transferee are not purchased by the Company and/or its assignee(s) as provided in this Section, then the Holder may sell or otherwise transfer such Shares to that Proposed Transferee at the Offered Price or at a higher price, provided that such sale or other transfer is consummated within 120 days after the date of the Notice, that any such sale or other transfer is effected in accordance with any applicable securities laws and that the Proposed Transferee agrees in writing that the provisions of this Section shall continue to apply to the Shares in the hands of such Proposed Transferee. If the Shares described in the Notice are not transferred to the Proposed Transferee within such period, a new Notice shall be given to the Company, and the Company and/or its assignees shall again be offered the Right of First Refusal before any Shares held by the Holder may be sold or otherwise transferred.

6. Exception for Certain Family Transfers. Anything to the contrary contained in this Section notwithstanding, the transfer of any or all of the Shares during the Optionee’s lifetime or on the Optionee’s death by will or intestacy to the Optionee’s immediate family or a trust for the benefit of the Optionee’s immediate family shall be exempt from the provisions of this Section. “Immediate Family” as used herein shall mean spouse, lineal descendant or antecedent, father, mother, brother or sister. In such case, the transferee or other recipient shall receive and hold the Shares so transferred subject to the provisions of this Section, and there shall be no further transfer of such Shares except in accordance with the terms of this Section.

7. Termination of Right of First Refusal. The Right of First Refusal shall terminate as to any Shares upon the earlier to occur of (i) the consummation of a Change of Control or (ii) the first sale of Common Stock of the Company to the general public pursuant to a registration statement filed with and declared effective by the Securities and Exchange Commission under the Securities Act.

E. Special Tax Election

The acquisition of the Purchased Shares may result in adverse tax consequences which may be avoided or mitigated by filing an election under Code Section 83(b). Such election must be filed within thirty (30) days after the date of this Agreement. A description of the tax consequences applicable to the acquisition of the Purchased Shares and the form for making the Code Section 83(b) election are set forth in Exhibit II. OPTIONEE SHOULD CONSULT WITH HIS OR HER TAX ADVISOR TO DETERMINE THE TAX CONSEQUENCES OF ACQUIRING THE PURCHASED SHARES AND THE ADVANTAGES AND DISADVANTAGES OF FILING THE CODE SECTION 83(b) ELECTION. OPTIONEE ACKNOWLEDGES THAT IT IS OPTIONEE’S SOLE RESPONSIBILITY, AND NOT THE COMPANY’S, TO FILE A TIMELY ELECTION UNDER CODE SECTION 83(b), EVEN IF OPTIONEE REQUESTS THE COMPANY OR ITS REPRESENTATIVES TO MAKE THIS FILING ON HIS OR HER BEHALF.

Exhibit C to Notice of Grant of Stock Option (Early Exercise)

Page 5

F. General Provisions

1. Assignment. The Company may assign the Repurchase Right to any person or entity selected by the Board, including (without limitation) one or more stockholders of the Company.

2. At Will Employment. Nothing in this Agreement or in the Plan shall confer upon Optionee any right to continue in Service for any period of specific duration or interfere with or otherwise restrict in any way the rights of the Company (or any Affiliate employing or retaining Optionee) or of Optionee, which rights are hereby expressly reserved by each, to terminate Optionee’s Service at any time for any reason, with or without cause.

3. Notices. Any notice required to be given under this Agreement shall be in writing and shall be deemed effective upon personal delivery or upon deposit in the U.S. mail, postage prepaid and properly addressed to the party entitled to such notice at the address indicated below such party’s signature line on this Agreement or at such other address as such party may designate by ten (10) days advance written notice under this paragraph to all other parties to this Agreement.

Optionee generally consents to the delivery of any notice pursuant to the Delaware General Corporation Law (the “DGCL”), as amended or superseded from time to time, by electronic transmission pursuant to Section 232 of the DGCL (“Electronic Notice”) at the electronic mail address or the facsimile number as set forth in the books of the Company. To the extent that any notice given via electronic transmission is returned or undeliverable for any reason, the foregoing consent shall be deemed to have been revoked until a new or corrected electronic mail address has been provided, and such attempted Electronic Notice shall be ineffective and deemed to not have been given. Optionee agrees to promptly notify the Company of any change in Optionee’s electronic mail address, but failure to do so shall not affect the foregoing.

4. No Waiver. The failure of the Company in any instance to exercise the Repurchase Right shall not constitute a waiver of any other repurchase rights that may subsequently arise under the provisions of this Agreement or any other agreement between the Company and Optionee. No waiver of any breach or condition of this Agreement shall be deemed to be a waiver of any other or subsequent breach or condition, whether of like or different nature.

5. Cancellation of Shares. If the Company shall make available, at the time and place and in the amount and form provided in this Agreement, the consideration for the Purchased Shares to be repurchased in accordance with the provisions of this Agreement, then from and after such time, the person from whom such shares are to be repurchased shall no longer have any rights as a holder of such shares (other than the right to receive payment of such consideration in accordance with this Agreement). Such shares shall be deemed purchased in accordance with the applicable provisions hereof, and the Company shall be deemed the owner and holder of such shares, whether or not the certificates therefor have been delivered as required by this Agreement.

Exhibit C to Notice of Grant of Stock Option (Early Exercise)

Page 6

G. Miscellaneous Provisions

1. Optionee Undertaking. Optionee hereby agrees to take whatever additional action and execute whatever additional documents the Company may deem necessary or advisable in order to carry out or effect one or more of the obligations or restrictions imposed on either Optionee or the Purchased Shares pursuant to the provisions of this Agreement.

2. Agreement is Entire Contract. This Agreement constitutes the entire contract between the parties hereto with regard to the subject matter hereof. This Agreement is made pursuant to the provisions of the Plan and shall in all respects be construed in conformity with the terms of the Plan.

3. Governing Law. This Agreement shall be governed by, and construed in accordance with, the laws of the State of Texas without resort to that state’s conflict-of-laws rules.

4. Counterparts. This Agreement may be executed in counterparts, each of which shall be deemed to be an original, but all of which together shall constitute one and the same instrument.

5. Successors and Assigns. The provisions of this Agreement shall inure to the benefit of, and be binding upon, the Company and its successors and assigns and upon Optionee, Optionee’s permitted assigns and the legal representatives, heirs and legatees of Optionee’s estate, whether or not any such person shall have become a party to this Agreement and have agreed in writing to join herein and be bound by the terms hereof.

Exhibit C to Notice of Grant of Stock Option (Early Exercise)

Page 7

IN WITNESS WHEREOF, the parties have executed this Stock Purchase Agreement on the day and year first indicated above.

Exhibit C to Notice of Grant of Stock Option (Early Exercise)

Page 8

SPOUSAL ACKNOWLEDGMENT

The undersigned spouse of Optionee has read and hereby approves the foregoing Stock Purchase Agreement. In consideration of the Company’s granting Optionee the right to acquire the Purchased Shares in accordance with the terms of such Agreement, the undersigned hereby agrees to be irrevocably bound by all the terms of such Agreement, including (without limitation) the right of the Company (or its assigns) to purchase any Purchased Shares in which Optionee is not vested at time of his or her cessation of Service.

EXHIBIT I

ASSIGNMENT SEPARATE FROM CERTIFICATE

ASSIGNMENT SEPARATE FROM CERTIFICATE

FOR VALUE RECEIVED _________________________ hereby sell(s), assign(s) and transfer(s) unto Mavenir Systems, Inc. (the “Company”), _______________ (            ) shares of the Common Stock of the Company standing in his or her name on the books of the Company represented by Certificate No. _________ herewith and do(es) hereby irrevocably constitute and appoint _____________________, Attorney to transfer the said stock on the books of the Company with full power of substitution in the premises.

Instruction: Please do not fill in any blanks other than the signature line. Please sign exactly as you would like your name to appear on the issued stock certificate. The purpose of this assignment is to enable the Company to exercise the Repurchase Right without requiring additional signatures on the part of Optionee.

Exhibit C-I to Notice of Grant of Stock Option (Early Exercise)

Page 1

EXHIBIT II

FEDERAL INCOME TAX CONSEQUENCES AND

SECTION 83(b) TAX ELECTION

FEDERAL INCOME TAX CONSEQUENCES AND

SECTION 83(b) TAX ELECTION

H. Federal Income Tax Consequences and Section 83(b) Election For Exercise of Non-Qualified Option. If the Purchased Shares are acquired pursuant to the exercise of a Non-Qualified Stock Option, as specified in the Grant Notice, then under Code Section 83, the excess of the Fair Market Value of the Purchased Shares on the date any forfeiture restrictions applicable to such shares lapse over the Exercise Price paid for those shares will be reportable as ordinary income on the lapse date. For this purpose, the term “forfeiture restrictions” includes the right of the Company to repurchase the Purchased Shares pursuant to the Repurchase Right. However, Optionee may elect under Code Section 83(b) to be taxed at the time the Purchased Shares are acquired, rather than when and as such Purchased Shares cease to be subject to such forfeiture restrictions. Such election must be filed with the Internal Revenue Service within thirty (30) days after the date of the Agreement. Even if the Fair Market Value of the Purchased Shares on the date of the Agreement equals the Exercise Price paid (and thus no tax is payable), the election must be made to avoid adverse tax consequences in the future. The form for making this election is attached as part of this exhibit. FAILURE TO MAKE THIS FILING WITHIN THE APPLICABLE THIRTY (30)-DAY PERIOD WILL RESULT IN THE RECOGNITION OF ORDINARY INCOME BY OPTIONEE AS THE FORFEITURE RESTRICTIONS LAPSE.

I. Federal Income Tax Consequences and Conditional Section 83(b) Election For Exercise of Incentive Stock Option. If the Purchased Shares are acquired pursuant to the exercise of an Incentive Stock Option, as specified in the Grant Notice, then the following tax principles shall be applicable to the Purchased Shares:

1. For regular tax purposes, no taxable income will be recognized at the time the Option is exercised.

2. The excess of (a) the Fair Market Value of the Purchased Shares on the date the Option is exercised or (if later) on the date any forfeiture restrictions applicable to the Purchased Shares lapse over (b) the Exercise Price paid for the Purchased Shares will be includible in Optionee’s taxable income for alternative minimum tax purposes.

3. If Optionee makes a disqualifying disposition of the Purchased Shares, then Optionee will recognize ordinary income in the year of such disposition equal in amount to the excess of (a) the Fair Market Value of the Purchased Shares on the date the Option is exercised or (if later) on the date any forfeiture restrictions applicable to the Purchased Shares lapse over (b) the Exercise Price paid for the Purchased Shares. Any additional gain recognized upon the disqualifying disposition will be either short-term or long-term capital gain depending upon the period for which the Purchased Shares are held prior to the disposition.

4. For purposes of the foregoing, the term “forfeiture restrictions” will include the right of the Company to repurchase the Purchased Shares pursuant to the Repurchase Right. The term “disqualifying disposition” means any sale or other disposition¹ of the Purchased Shares within two (2) years after the Grant Date or within one (1) year after the exercise date of the Option.

Exhibit C-II to Notice of Grant of Stock Option (Early Exercise)

Page 1

5. The Code Section 83(b) election will be effective in limiting Optionee’s alternative minimum taxable income to the excess of the Fair Market Value of the Purchased Shares at the time the Option is exercised over the Exercise Price paid for those shares.

Page 2 of the attached form for making the election should be filed with any election made in connection with the exercise of an Incentive Stock Option.

Exhibit C-II to Notice of Grant of Stock Option (Early Exercise)

Page 2

SECTION 83(b) ELECTION

This statement is being made under Section 83(b) of the Internal Revenue Code, pursuant to Treas. Reg. Section 1.83-2.

THIS PAGE 2 IS TO BE ATTACHED TO ANY SECTION 83(b) ELECTION FILED IN CONNECTION WITH THE EXERCISE OF AN INCENTIVE STOCK OPTION UNDER THE FEDERAL TAX LAWS.

The property described in the above Section 83(b) election is comprised of shares of common stock acquired pursuant to the exercise of an incentive stock option under Section 422 of the Internal Revenue Code (the “Code”). Accordingly, the purpose of this election is to have the alternative minimum taxable income attributable to the purchased shares measured by the amount by which the fair market value of such shares at the time of their transfer to the Taxpayer exceeds the purchase price paid for the shares. In the absence of this election, such alternative minimum taxable income would be measured by the spread between the fair market value of the purchased shares and the purchase price which exists on the various lapse dates in effect for the forfeiture restrictions applicable to such shares.