ARIBA, INC. 1999 EQUITYINCENTIVE PLAN (AS AMENDED ANDRESTATED EFFECTIVE DECEMBER 1, 2011)

EXHIBIT 10.54

ARIBA, INC.

1999 EQUITY INCENTIVE PLAN

(AS AMENDED AND RESTATED EFFECTIVE DECEMBER 1, 2011)

Exhibit

TABLE OF CONTENTS

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Exhibit 10.54

ARIBA, INC.

1999 EQUITY INCENTIVE PLAN

ARTICLE 1. INTRODUCTION.

The Board adopted the Plan effective June 23, 1999. The Plan was most recently amended on December 1, 2011. The purpose of the Plan is to promote the long-term success of the Company and the creation of stockholder value by (a) encouraging Employees, Outside Directors and Consultants to focus on critical long-range objectives, (b) encouraging the attraction and retention of Employees, Outside Directors and Consultants with exceptional qualifications and (c) linking Employees, Outside Directors and Consultants directly to stockholder interests through increased stock ownership. The Plan seeks to achieve this purpose by providing for Awards in the form of Restricted Shares, Stock Units, Options (which may constitute ISOs or NSOs) or stock appreciation rights.

The Plan shall be governed by, and construed in accordance with, the laws of the State of Delaware (except their choice-of-law provisions).

ARTICLE 2. ADMINISTRATION.

2.1 Committee Composition. The Compensation Committee of the Board shall administer the Plan. The Committee shall consist exclusively of two or more members of the Board, who shall be appointed by the Board. In addition, each member of the Committee shall meet the following requirements:

(a) Any listing standards prescribed by the principal securities market on which the Company’s equity securities are traded;

(b) Such requirements as the Internal Revenue Service may establish for outside directors acting under plans intended to qualify for exemption under Section 162(m)(4)(C) of the Code;

(c) Such requirements as the Securities and Exchange Commission may establish for administrators acting under plans intended to qualify for exemption under Rule 16b-3 (or its successor) under the Exchange Act; and

(d) Any other requirements imposed by applicable law, regulations or rules.

2.2 Committee Responsibilities. The Committee shall (a) select the Employees, Outside Directors and Consultants who are to receive Awards under the Plan, (b) determine the type, number, vesting requirements and other features and conditions of such Awards, (c) interpret the Plan, (d) make all other decisions relating to the operation of the Plan

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and (e) carry out any other duties delegated to it by the Board under the Plan. The Committee may adopt such rules or guidelines as it deems appropriate to implement the Plan. The Committee’s determinations under the Plan shall be final and binding on all persons.

2.3 Non-Officer Grants. The Board may also appoint a secondary committee of the Board, which shall be composed of one or more directors of the Company who need not satisfy the requirements of Section 2.1. Such secondary committee may administer the Plan with respect to Employees and Consultants who are not considered officers or directors of the Company under Section 16 of the Exchange Act, may grant Awards under the Plan to such Employees and Consultants and may determine all features and conditions of such Awards. Within the limitations of this Section 2.3, any reference in the Plan to the Committee shall include such secondary committee.

ARTICLE 3. SHARES AVAILABLE FOR GRANTS.

3.1 Basic Limitation. Common Shares issued pursuant to the Plan may be authorized but unissued shares or treasury shares. The aggregate number of Common Shares issued under the Plan shall not exceed (a) 33,041,748¹ plus (b) the additional Common Shares described in Section 3.2. The number of Common Shares that are subject to Awards outstanding at any time under the Plan shall not exceed the number of Common Shares that then remain available for issuance under the Plan. All Common Shares available under the Plan may be issued upon the exercise of ISOs. The limitation of this Section 3.1 shall be subject to adjustment pursuant to Article 10.

3.2 Shares Returned to Reserve. To the extent that Options, SARs or Stock Units are forfeited or expire for any other reason before being exercised or settled in full, the Common Shares subject to such Options, SARs or Stock Units shall again become available for issuance under the Plan. If SARs are exercised, then only the number of Common Shares (if any) actually issued in settlement of such SARs shall reduce the number available under Section 3.1 and the balance shall again become available for issuance under the Plan. If Stock Units are settled, then only the number of Common Shares (if any) actually issued in settlement of such Stock Units shall reduce the number available under Section 3.1 and the balance shall again become available for issuance under the Plan. If Restricted Shares or Common Shares issued upon the exercise of Options are reacquired by the Company pursuant to a forfeiture provision or for any other reason, then such Common Shares shall again become available for issuance under the Plan. Shares applied to pay the Exercise Price of Options or to satisfy tax withholding obligations related to any Award shall again become available for issuance under the Plan. To the extent that an Award is settled in cash rather than Shares, the cash settlement shall not reduce the number of Shares available for issuance under the Plan.

3.3 Dividend Equivalents. Any dividend equivalents paid or credited under the Plan with respect to Stock Units shall not be applied against the number of Common Shares that may be issued under the Plan, whether or not such dividend equivalents are converted into Stock Units.

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ARTICLE 4. ELIGIBILITY.

4.1 Incentive Stock Options. Only Employees who are common-law employees of the Company, a Parent or a Subsidiary shall be eligible for the grant of ISOs. In addition, an Employee who owns more than 10% of the total combined voting power of all classes of outstanding stock of the Company or any of its Parents or Subsidiaries shall not be eligible for the grant of an ISO unless the additional requirements set forth in Section 422(c)(5) of the Code are satisfied.

4.2 Other Grants. Only Employees, Outside Directors and Consultants shall be eligible for the grant of Restricted Shares, Stock Units, NSOs or SARs.

ARTICLE 5. OPTIONS.

5.1 Stock Option Agreement. Each grant of an Option under the Plan shall be evidenced by a Stock Option Agreement between the Optionee and the Company. Such Option shall be subject to all applicable terms of the Plan and may be subject to any other terms that are not inconsistent with the Plan. The Stock Option Agreement shall specify whether the Option is an ISO or an NSO. The provisions of the various Stock Option Agreements entered into under the Plan need not be identical. Options may be granted in consideration of a reduction in the Optionee’s other compensation.

5.2 Number of Shares. Each Stock Option Agreement shall specify the number of Common Shares subject to the Option and shall provide for the adjustment of such number in accordance with Article 10. Options granted to an Optionee in a single fiscal year of the Company shall not cover more than 1,500,000 Common Shares, except that Options granted to a new Employee in the fiscal year of the Company in which his or her Service commences may cover up to 2,000,000 Common Shares. The limitations set forth in the preceding sentence shall be subject to adjustment in accordance with Article 10.

5.3 Exercise Price. Each Stock Option Agreement shall specify the Exercise Price, which shall not be less than 100% of the Fair Market Value of a Common Share on the date of grant. The preceding sentence shall not apply to Options granted pursuant to an assumption of, or substitution for, another option in a manner that would satisfy the requirements of Section 424(a) of the Code, whether or not such Section is applicable.

5.4 Exercisability and Term. Each Stock Option Agreement shall specify the date or event when all or any installment of the Option is to become exercisable. The Stock Option Agreement shall also specify the term of the Option; provided that the term of an ISO shall in no event exceed 10 years from the date of grant. A Stock Option Agreement may provide for accelerated exercisability in the event of the Optionee’s death, disability or retirement or other events and may provide for expiration prior to the end of its term in the event of the termination of the Optionee’s Service. Options may be awarded in combination with SARs, and such an Award may provide that the Options will not be exercisable unless the related SARs are forfeited.

5.5 Effect of Change in Control. The Committee may determine, at the time of granting an Option or thereafter, that such Option shall become exercisable as to all or part of

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the Common Shares subject to such Option in the event that a Change in Control occurs with respect to the Company or in the event that the Optionee is subject to an Involuntary Termination after a Change in Control. However, in the case of an ISO, the acceleration of exercisability shall not occur without the Optionee’s written consent. In addition, acceleration of exercisability may be required under Section 10.3.

5.6 Modification or Extension of Options. Within the limitations of the Plan, the Committee may modify or extend outstanding Options or may substitute new Options granted under the Plan for outstanding options granted by another issuer. Except in connection with a corporate transaction involving the Company (including, without limitation, any stock dividend, stock split, extraordinary cash dividend, recapitalization, reorganization, merger, consolidation, split-up, spin-off, combination, or exchange of shares), the terms of outstanding Options shall not be amended to reduce the Exercise Price of such Options or cancel such Options in exchange for cash or other Awards, or for Options with an Exercise Price that is less than the Exercise Price of the original Options, without stockholder approval. No modification of an Option shall, without the consent of the Optionee, alter or impair his or her rights or obligations under such Option.

5.7 Buyout Provisions. The Committee may at any time (a) offer to buy out for a payment in cash or cash equivalents an Option previously granted or (b) authorize an Optionee to elect to cash out an Option previously granted, in either case at such time and based upon such terms and conditions as the Committee shall establish. Except in connection with a corporate transaction involving the Company (including, without limitation, any reorganization, merger, consolidation, split-up, spin-off, combination, or exchange of shares), this Section 5.7 shall not apply to an Option with an Exercise Price that exceeds the Fair Market Value of a Common Share on the date of the buyout, unless the buyout has been approved by the Company’s stockholders.

ARTICLE 6. PAYMENT FOR OPTION SHARES.

6.1 General Rule. The entire Exercise Price of Common Shares issued upon exercise of Options shall be payable in cash or cash equivalents at the time when such Common Shares are purchased, except that the Committee at its sole discretion may accept payment of the Exercise Price in any other form(s) described in this Article 6. However, if the Optionee is an Outside Director or executive officer of the Company, he or she may pay the Exercise Price in a form other than cash or cash equivalents only to the extent permitted by Section 13(k) of the Exchange Act.

6.2 Exercise/Sale. With the Committee’s consent, all or any part of the Exercise Price and any withholding taxes may be paid by delivering (on a form prescribed by the Company) an irrevocable direction to a securities broker approved by the Company to sell all or part of the Common Shares being purchased under the Plan and to deliver all or part of the sales proceeds to the Company.

6.3 Other Forms of Payment. With the Committee’s consent, all or any part of the Exercise Price and any withholding taxes may be paid in any other form that is consistent with applicable laws, regulations and rules.

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ARTICLE 7. STOCK APPRECIATION RIGHTS.

7.1 SAR Agreement. Each grant of a SAR under the Plan shall be evidenced by a SAR Agreement between the Optionee and the Company. Such SAR shall be subject to all applicable terms of the Plan and may be subject to any other terms that are not inconsistent with the Plan. The provisions of the various SAR Agreements entered into under the Plan need not be identical. SARs may be granted in consideration of a reduction in the Optionee’s other compensation.

7.2 Number of Shares. Each SAR Agreement shall specify the number of Common Shares to which the SAR pertains and shall provide for the adjustment of such number in accordance with Article 10. SARs granted to an Optionee in a single calendar year shall in no event pertain to more than 1,500,000 Common Shares, except that SARs granted to a new Employee in the fiscal year of the Company in which his or her Service commences may pertain to a maximum of 2,000,000 Common Shares. The limitations set forth in the preceding sentence shall be subject to adjustment in accordance with Article 10.

7.3 Exercise Price. Each SAR Agreement shall specify the Exercise Price, which shall in no event be less than 100% of the Fair Market Value of a Common Share on the date of grant. The preceding sentence shall not apply to SARs granted pursuant to an assumption of, or substitution for, another SAR in a manner that would satisfy the requirements of Section 424(a) of the Code if such Section were applicable.

7.4 Exercisability and Term. Each SAR Agreement shall specify the date when all or any installment of the SAR is to become exercisable. The SAR Agreement shall also specify the term of the SAR. A SAR Agreement may provide for accelerated exercisability in the event of the Optionee’s death, disability or retirement or other events and may provide for expiration prior to the end of its term in the event of the termination of the Optionee’s Service. SARs may be awarded in combination with Options, and such an Award may provide that the SARs will not be exercisable unless the related Options are forfeited. A SAR may be included in an ISO only at the time of grant but may be included in an NSO at the time of grant or thereafter. A SAR granted under the Plan may provide that it will be exercisable only in the event of a Change in Control.

7.5 Effect of Change in Control. The Committee may determine, at the time of granting a SAR or thereafter, that such SAR shall become exercisable as to all or part of the Common Shares subject to such SAR in the event that the Company is subject to a Change in Control or in the event that the Optionee is subject to an Involuntary Termination after a Change in Control. In addition, acceleration of exercisability may be required under Section 10.3.

7.6 Exercise of SARs. Upon exercise of a SAR, the Optionee (or any person having the right to exercise the SAR after his or her death) shall receive from the Company (a) Common Shares, (b) cash or (c) a combination of Common Shares and cash, as the Committee shall determine. The amount of cash and/or the Fair Market Value of Common Shares received upon exercise of SARs shall, in the aggregate, be equal to the amount by which the Fair Market Value (on the date of exercise) of the Common Shares subject to the SARs exceeds the Exercise Price. If, on the date when a SAR expires, the Exercise Price is less than

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the Fair Market Value on such date but any portion of such SAR has not been exercised or surrendered, then such SAR shall automatically be deemed to be exercised as of such date with respect to such portion. A SAR Agreement may also provide for an automatic exercise of the SAR on an earlier date.

7.7 Modification or Extension of SARs. Within the limitations of the Plan, the Committee may modify or extend outstanding SARs or may substitute new SARs granted under the Plan for outstanding options granted by another issuer. Except in connection with a corporate transaction involving the Company (including, without limitation, any stock dividend, stock split, extraordinary cash dividend, recapitalization, reorganization, merger, consolidation, split-up, spin-off, combination, or exchange of shares), the terms of outstanding SARs shall not be amended to reduce the Exercise Price of such SARs or cancel such SARs in exchange for cash or other Awards, or for SARs with an Exercise Price that is less than the Exercise Price of the original SARs, without stockholder approval. No modification of a SAR shall, without the consent of the Optionee, alter or impair his or her rights or obligations under such SAR.

ARTICLE 8. RESTRICTED SHARES.

8.1 Restricted Stock Agreement. Each grant of Restricted Shares under the Plan shall be evidenced by a Restricted Stock Agreement between the recipient and the Company. Such Restricted Shares shall be subject to all applicable terms of the Plan and may be subject to any other terms that are not inconsistent with the Plan. The provisions of the various Restricted Stock Agreements entered into under the Plan need not be identical.

8.2 Payment for Awards. Restricted Shares may be sold or awarded under the Plan for such consideration as the Committee may determine, including (without limitation) cash, cash equivalents, property, past services and future services. Within the limitations of the Plan, the Committee may accept the cancellation of outstanding options in return for the grant of Restricted Shares.

8.3 Vesting Conditions. Each Award of Restricted Shares may or may not be subject to vesting. Vesting shall occur, in full or in installments, upon satisfaction of the conditions specified in the Restricted Stock Agreement. A Restricted Stock Agreement may provide for accelerated vesting in the event of the Participant’s death, disability or retirement or other events. The Committee may determine, at the time of granting Restricted Shares or thereafter, that all or part of such Restricted Shares shall become vested in the event that a Change in Control occurs with respect to the Company or in the event that the Participant is subject to an Involuntary Termination after a Change in Control. Notwithstanding the above, Awards of Restricted Shares made on or after December 1, 2011 shall be subject to minimum vesting requirements as follows: Awards subject to time-based vesting shall vest in full in not less than 36 months from the vesting commencement date contained in the Award and Awards subject to performance-based vesting shall vest in full in not less than 12 months from the vesting commencement date contained in the Award; provided, however, that (i) these minimum vesting requirements shall not limit any vesting accelerations provisions that may apply to an Award upon termination of the holder’s employment, a change of control or divestiture of a business unit of the Company, or other similar circumstance, and (ii) 10% of the total number of Common Shares available for grant under the Plan, measured annually, shall be exempted from

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the limitations of this sentence and of the final sentence in Section 9.3 below. The annual measurement date referred to in the preceding sentence shall occur on the first day of each fiscal year except that, with respect to any fiscal year in which the stockholders approve an increase in shares reserved for issuance under the Plan, such measurement shall instead occur on the date of such stockholder approval.

8.4 Voting and Dividend Rights. The holders of Restricted Shares awarded under the Plan shall have the same voting, dividend and other rights as the Company’s other stockholders. A Restricted Stock Agreement, however, may require that any cash dividends paid on Restricted Shares (a) be accumulated and paid when such Restricted Shares vest or (b) be invested in additional Restricted Shares. Such additional Restricted Shares shall be subject to the same conditions and restrictions as the Award with respect to which the dividends were paid.

ARTICLE 9. STOCK UNITS.

9.1 Stock Unit Agreement. Each grant of Stock Units under the Plan shall be evidenced by a Stock Unit Agreement between the recipient and the Company. Such Stock Units shall be subject to all applicable terms of the Plan and may be subject to any other terms that are not inconsistent with the Plan. The provisions of the various Stock Unit Agreements entered into under the Plan need not be identical. Stock Units may be granted in consideration of a reduction in the recipient’s other compensation.

9.2 Payment for Awards. To the extent that an Award is granted in the form of Stock Units, no cash consideration shall be required of the Award recipients.

9.3 Vesting Conditions. Each Award of Stock Units may or may not be subject to vesting. Vesting shall occur, in full or in installments, upon satisfaction of the conditions specified in the Stock Unit Agreement. A Stock Unit Agreement may provide for accelerated vesting in the event of the Participant’s death, disability or retirement or other events. The Committee may determine, at the time of granting Stock Units or thereafter, that all or part of such Stock Units shall become vested in the event that the Company is subject to a Change in Control or in the event that the Participant is subject to an Involuntary Termination after a Change in Control. In addition, acceleration of vesting may be required under Section 10.3. Notwithstanding the above, Awards of Stock Units granted on or after December 1, 2011 shall be subject to minimum vesting requirements as follows: Awards subject to time-based vesting shall vest in full in not less than 36 months from the vesting commencement date contained in the Award and Awards subject to performance-based vesting shall vest in full in not less than 12 months from the vesting commencement date contained in the Award; provided, however, that (i) these minimum vesting requirements shall not limit any vesting accelerations provisions that may apply to an Award upon termination of the holder’s employment, a change of control or divestiture of a business unit of the Company, or other similar circumstance, and (ii) 10% of the total number of Common Shares available for grant under the Plan, measured annually, shall be exempted from the limitations of this sentence and of the final sentence in Section 8.3 above. The annual measurement date referred to in the preceding sentence shall occur on the first day of each fiscal year except that, with respect to any fiscal year in which the stockholders approve an increase in shares reserved for issuance under the Plan, such measurement shall instead occur on the date of such stockholder approval.

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9.4 Voting and Dividend Rights. The holders of Stock Units shall have no voting rights. Prior to settlement or forfeiture, any Stock Unit awarded under the Plan may, at the Committee’s discretion, carry with it a right to dividend equivalents. Such right entitles the holder to be credited with an amount equal to all cash dividends paid on one Common Share while the Stock Unit is outstanding. Dividend equivalents may be converted into additional Stock Units. Settlement of dividend equivalents may be made in the form of cash, in the form of Common Shares, or in a combination of both. Prior to distribution, any dividend equivalents that are not paid shall be subject to the same conditions and restrictions as the Stock Units to which they attach.

9.5 Form and Time of Settlement of Stock Units. Settlement of vested Stock Units may be made in the form of (a) cash, (b) Common Shares or (c) any combination of both, as determined by the Committee. The actual number of Stock Units eligible for settlement may be larger or smaller than the number included in the original Award, based on predetermined performance factors. Methods of converting Stock Units into cash may include (without limitation) a method based on the average Fair Market Value of Common Shares over a series of trading days. Vested Stock Units may be settled in such manner and at such times as specified in the Stock Unit Agreement. The distribution may occur or commence when all vesting conditions applicable to the Stock Units have been satisfied or have lapsed, or it may be deferred to any later date. The amount of a deferred distribution may be increased by an interest factor or by dividend equivalents as specified in the Stock Unit Agreement. Until an Award of Stock Units is settled, the number of such Stock Units shall be subject to adjustment pursuant to Article 10.

9.6 Creditors’ Rights. A holder of Stock Units shall have no rights other than those of a general creditor of the Company. Stock Units represent an unfunded and unsecured obligation of the Company, subject to the terms and conditions of the applicable Stock Unit Agreement.

ARTICLE 10. PROTECTION AGAINST DILUTION.

10.1 Adjustments. In the event of a subdivision of the outstanding Common Shares, a declaration of a dividend payable in Common Shares or a combination or consolidation of the outstanding Common Shares (by reclassification or otherwise) into a lesser number of Common Shares, corresponding adjustments shall automatically be made in each of the following:

(a) The number of Options, SARs, Restricted Shares and Stock Units available for future Awards under Article 3;

(b) The limitations set forth in Sections 5.2 and 7.2;

(c) The number of Common Shares covered by each outstanding Option and SAR;

(d) The Exercise Price under each outstanding Option and SAR; or

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(e) The number of Stock Units included in any prior Award that has not yet been settled.

In the event of a declaration of an extraordinary dividend payable in a form other than Common Shares in an amount that has a material effect on the price of Common Shares, a recapitalization, a spin-off or a similar occurrence, the Committee shall make such adjustments as it, in its sole discretion, deems appropriate in one or more of the foregoing. Except as provided in this Article 10, a Participant shall have no rights by reason of any issuance by the Company of stock of any class or securities convertible into stock of any class, any subdivision or consolidation of shares of stock of any class, the payment of any stock dividend or any other increase or decrease in the number of shares of stock of any class.

10.2 Dissolution or Liquidation. To the extent not previously exercised or settled, Options, SARs and Stock Units shall terminate immediately prior to the dissolution or liquidation of the Company.

10.3 Reorganizations. In the event that the Company is a party to a merger or consolidation, all outstanding Awards shall be subject to the agreement of merger or consolidation. Such agreement shall provide for one or more of the following:

(a) The continuation of such outstanding Awards by the Company (if the Company is the surviving corporation).

(b) The assumption of such outstanding Awards by the surviving corporation or its parent, provided that the assumption of Options or SARs shall comply with Section 424(a) of the Code (whether or not the Options are ISOs).

(c) The substitution by the surviving corporation or its parent of new awards for such outstanding Awards, provided that the substitution of Options or SARs shall comply with Section 424(a) of the Code (whether or not the Options are ISOs).

(d) Full exercisability of outstanding Options and SARs and full vesting of the Common Shares subject to such Options and SARs, followed by the cancellation of such Options and SARs. The full exercisability of such Options and SARs and full vesting of such Common Shares may be contingent on the closing of such merger or consolidation. The Optionees shall be able to exercise such Options and SARs during a period of not less than five full business days preceding the closing date of such merger or consolidation, unless (i) a shorter period is required to permit a timely closing of such merger or consolidation and (ii) such shorter period still offers the Optionees a reasonable opportunity to exercise such Options and SARs. Any exercise of such Options and SARs during such period may be contingent on the closing of such merger or consolidation.

(e) The cancellation of outstanding Options and SARs and a payment to the Optionees equal to the excess of (i) the Fair Market Value of the

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Common Shares subject to such Options and SARs (whether or not such Options and SARs are then exercisable or such Common Shares are then vested) as of the closing date of such merger or consolidation over (ii) their Exercise Price. Such payment shall be made in the form of cash, cash equivalents, or securities of the surviving corporation or its parent with a Fair Market Value equal to the required amount. Subject to any requirements of Section 409A of the Code necessary to avoid application of Section 409A(a)(1) of the Code with respect to the Awards, such payment may be made in installments and may be deferred until the date or dates when such Options and SARs would have become exercisable or such Common Shares would have vested. Such payment may be subject to vesting based on the Optionee’s continuing Service, provided that the vesting schedule shall not be less favorable to the Optionee than the schedule under which such Options and SARs would have become exercisable or such Common Shares would have vested. If the Exercise Price of the Common Shares subject to such Options and SARs exceeds the Fair Market Value of such Common Shares, then such Options and SARs may be cancelled without making a payment to the Optionees. For purposes of this SubSection (e), the Fair Market Value of any security shall be determined without regard to any vesting conditions that may apply to such security.

(f) The cancellation of outstanding Stock Units and a payment to the Participants equal to the Fair Market Value of the Common Shares subject to such Stock Units (whether or not such Stock Units are then vested) as of the closing date of such merger or consolidation. Such payment shall be made in the form of cash, cash equivalents, or securities of the surviving corporation or its parent with a Fair Market Value equal to the required amount. Such payment may be made in installments and may be deferred until the date or dates when such Stock Units would have vested. Such payment may be subject to vesting based on the Participant’s continuing Service, provided that the vesting schedule shall not be less favorable to the Participant than the schedule under which such Stock Units would have vested. Notwithstanding anything to the contrary contained herein, if required to avoid adverse tax consequences under Section 409A(a)(1) of the Code, the distribution date(s) applicable to Stock Units cancelled under this SubSection (f) shall be the date(s) specified in the Stock Unit Agreement. For purposes of this SubSection (f), the Fair Market Value of any security shall be determined without regard to any vesting conditions that may apply to such security.

ARTICLE 11. AWARDS UNDER OTHER PLANS.

The Company may grant awards under other plans or programs. Such awards may be settled in the form of Common Shares issued under this Plan. Such Common Shares shall be treated for all purposes under the Plan like Common Shares issued in settlement of Stock Units and shall, when issued, reduce the number of Common Shares available under Article 3.

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ARTICLE 12. PAYMENT OF DIRECTOR’S FEES IN SECURITIES.

12.1 Effective Date. No provision of this Article 12 shall be effective unless and until the Board has determined to implement such provision.

12.2 Elections to Receive NSOs, Restricted Shares or Stock Units. An Outside Director may elect to receive his or her annual retainer payments and/or meeting fees from the Company in the form of cash, NSOs, Restricted Shares or Stock Units, or a combination thereof, as determined by the Board. Such NSOs, Restricted Shares and Stock Units shall be issued under the Plan. An election under this Article 12 shall be filed with the Company on the prescribed form.

12.3 Number and Terms of NSOs, Restricted Shares or Stock Units. The number of NSOs, Restricted Shares or Stock Units to be granted to Outside Directors in lieu of annual retainers and meeting fees that would otherwise be paid in cash shall be calculated in a manner determined by the Board. The terms of such NSOs, Restricted Shares or Stock Units shall also be determined by the Board.

ARTICLE 13. LIMITATION ON RIGHTS.

13.1 Retention Rights. Neither the Plan nor any Award granted under the Plan shall be deemed to give any individual a right to remain an Employee, Outside Director or Consultant. The Company and its Parents, Subsidiaries and Affiliates reserve the right to terminate the Service of any Employee, Outside Director or Consultant at any time, with or without cause, subject to applicable laws, the Company’s certificate of incorporation and by-laws and a written employment agreement (if any).

13.2 Stockholders’ Rights. A Participant shall have no dividend rights, voting rights or other rights as a stockholder with respect to any Common Shares covered by his or her Award prior to the time when a stock certificate for such Common Shares is issued or, if applicable, the time when he or she becomes entitled to receive such Common Shares by filing any required notice of exercise, paying any required Exercise Price, and satisfying any applicable withholding obligations. No adjustment shall be made for cash dividends or other rights for which the record date is prior to such time, except as expressly provided in the Plan or an Award Agreement.

13.3 Regulatory Requirements. Any other provision of the Plan notwithstanding, the obligation of the Company to issue Common Shares under the Plan shall be subject to all applicable laws, rules and regulations and such approval by any regulatory body as may be required. The Company reserves the right to restrict, in whole or in part, the delivery of Common Shares pursuant to any Award prior to the satisfaction of all legal requirements relating to the issuance of such Common Shares, to their registration, qualification or listing or to an exemption from registration, qualification or listing.

ARTICLE 14. TAX MATTERS.

14.1 General. To the extent required by applicable federal, state, local or foreign law, a Participant or his or her successor shall make arrangements satisfactory to the

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Company for the satisfaction of any withholding tax obligations that arise in connection with any Awards granted under the Plan. The Company shall not be required to issue any Common Shares or make any cash payment under the Plan until such obligations are satisfied.

14.2 Share Withholding. To the extent that applicable law subjects a Participant to tax withholding obligations, the Committee may permit such Participant to satisfy all or part of such obligations by having the Company withhold all or a portion of any Common Shares that otherwise would be issued to him or her or by surrendering all or a portion of any Common Shares that he or she previously acquired. Such Common Shares shall be valued at their Fair Market Value on the date when they are withheld or surrendered. This Section 14.2 shall apply only to the minimum extent required by applicable tax laws.

14.3 Section 409A Matters. Except to the extent otherwise set forth in an Award Agreement, it is intended that Awards granted under the Plan be exempt from Section 409A of the Code, and any ambiguity in the terms of Awards and the Plan shall be interpreted consistently with this intent. To the extent an Award is not exempt from Section 409A of the Code, any ambiguity in the terms of such Award and the Plan shall be interpreted in a manner that to the maximum extent permissible supports compliance with the requirements of that statute such that Section 409A(a)(1) of the Code shall not apply. Notwithstanding anything in the Plan or an Award Agreement to the contrary, to the extent necessary to avoid application of Section 409A(a)(1) of the Code with respect to a Participant who is a “specified employee” within the meaning of Section 409A of the Code at the time of such Service termination, if the payment of any amount under an Award would result in the imposition of additional tax under Section 409A(a)(1) of the Code if paid to the Participant on or within the six (6) month period following Participant’s Service termination, then the payment of such amount will not be made until the date six (6) months and one (1) day following the date of Participant’s Service termination; provided that if the Participant dies thereafter but before the date that is six (6) months and one (1) day following Service termination, then such amount will be paid to the Participant’s estate as soon as practicable following his or her death. In addition, unless otherwise determined by the Committee, with respect to any Award subject to Section 409A of the Code that settles or pays as a result of a termination of the Participant’s Service, a Service termination shall mean a “separation of service” as defined under final Treasury Regulations issued under Section 409A of the Code.

ARTICLE 15. LIMITATION ON PAYMENTS.

15.1 Scope of Limitation. This Article 15 shall apply to an Award only if:

(a) The independent auditors selected for this purpose by the Committee (the “Auditors”) determine that the after-tax value of such Award to the Participant, taking into account the effect of all federal, state and local income taxes, employment taxes and excise taxes applicable to the Participant (including the excise tax under Section 4999 of the Code), will be greater after the application of this Article 15 than it was before the application of this Article 15; or

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(b) The Committee, at the time of making an Award under the Plan or at any time thereafter, specifies in writing that such Award shall be subject to this Article 15 (regardless of the after-tax value of such Award to the Participant).

If this Article 15 applies to an Award, it shall supersede any contrary provision of the Plan or of any Award granted under the Plan.

15.2 Basic Rule. In the event that the Auditors determine that any payment or transfer by the Company under the Plan to or for the benefit of a Participant (a “Payment”) would be nondeductible by the Company for federal income tax purposes because of the provisions concerning “excess parachute payments” in Section 280G of the Code, then the aggregate present value of all Payments shall be reduced (but not below zero) to the Reduced Amount. For purposes of this Article 15, the “Reduced Amount” shall be the amount, expressed as a present value, which maximizes the aggregate present value of the Payments without causing any Payment to be nondeductible by the Company because of Section 280G of the Code. For purposes of this Article 15, present value shall be determined in accordance with Section 280G(d)(4) of the Code.

15.3 Reduction of Payments. If the Auditors determine that any Payment would be nondeductible by the Company because of Section 280G of the Code, then the Company shall promptly give the Participant notice to that effect and a copy of the detailed calculation thereof and of the Reduced Amount. The Participant’s Payments will then be reduced in a manner that (a) first reduces any Payment subject to Code Section 409A (or if there are more than one such Payment, then all such Payments on a pro-rata basis) and then, to the extent necessary and in such manner as the Participant may elect, reduces any Payment(s) that is/are not subject to Code Section 409A; provided that if the Participant does not make such election within 10 days after receipt of the notice described above, then the Company may elect which and how much of the Payments shall be eliminated or reduced (as long as after such election the aggregate present value of the Payments equals the Reduced Amount) and shall notify the Participant promptly of such election; and (b) does not result in any Payment becoming subject to Code Section 409A(a)(1). All determinations made by the Auditors under this Article 15 shall be binding upon the Company and the Participant and shall be made within 60 days of the date when a Payment becomes payable or transferable. As promptly as practicable following such determination and the elections hereunder, the Company shall pay or transfer to or for the benefit of the Participant such amounts as are then due to him or her under the Plan and shall promptly pay or transfer to or for the benefit of the Participant in the future such amounts as become due to him or her under the Plan.

15.4 Overpayments and Underpayments. As a result of uncertainty in the application of Section 280G of the Code at the time of an initial determination by the Auditors hereunder, it is possible that Payments will have been made by the Company which should not have been made (an “Overpayment”) or that additional Payments which will not have been made by the Company could have been made (an “Underpayment”), consistent in each case with the calculation of the Reduced Amount hereunder. In the event that the Auditors, based upon the assertion of a deficiency by the Internal Revenue Service against the Company or the Participant that the Auditors believe has a high probability of success, determine that an Overpayment has

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been made, such Overpayment shall be treated for all purposes as a loan to the Participant that he or she shall repay to the Company, together with interest at the applicable federal rate provided in Section 7872(f)(2) of the Code; provided, however, that no amount shall be payable by the Participant to the Company if and to the extent that such payment would not reduce the amount that is subject to taxation under Section 4999 of the Code. In the event that the Auditors determine that an Underpayment has occurred, such Underpayment shall promptly be paid or transferred by the Company to or for the benefit of the Participant, together with interest at the applicable federal rate provided in Section 7872(f)(2) of the Code. All such payments under this Section 15.4 shall be made by the end of the Participant’s taxable year following the Participant’s taxable year in which the taxes that are the subject of the audit or litigation are remitted to the taxing authorities, or where as a result of such audit or litigation no taxes are remitted, the end of the Participant’s taxable year following the Participant’s taxable year in which the audit is complete or there is a final and non-appealable settlement or other resolution of the litigation.

15.5 Related Corporations. For purposes of this Article 15, the term “Company” shall include affiliated corporations to the extent determined by the Auditors in accordance with Section 280G(d)(5) of the Code.

ARTICLE 16. FUTURE OF THE PLAN.

16.1 Term of the Plan. The Plan shall remain in effect until the earlier of (a) the date when the Plan is terminated under Section 16.2, or (b) January 14, 2019.

16.2 Amendment or Termination. The Board may, at any time and for any reason, amend or terminate the Plan. No Awards shall be granted under the Plan after the termination thereof. The termination of the Plan, or any amendment thereof, shall not affect any Award previously granted under the Plan.

16.3 Stockholder Approval. An amendment of the Plan shall be subject to the approval of the Company’s stockholders only to the extent required by applicable laws, regulations or rules.

ARTICLE 17. DEFINITIONS.

17.1 “Affiliate” means any entity other than a Subsidiary, if the Company and/or one or more Subsidiaries own not less than 50% of such entity.

17.2 “Award” means any award of an Option, a SAR, a Restricted Share or a Stock Unit under the Plan.

17.3 “Board” means the Company’s Board of Directors, as constituted from time to time.

17.4 “Change in Control” means:

(a) The consummation of a merger or consolidation of the Company or any Subsidiary with or into another entity or any other corporate

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reorganization, if immediately after such transaction the Ownership Percentage (as defined below) of persons who were not stockholders of the Company immediately before such transaction is more than 50% of the Company after such transaction;

(b) The sale, transfer or other disposition of all or substantially all of the Company’s assets;

(c) A change in the composition of the Board over a period of 12 months such that individuals who are members of the Board at the beginning of such 12 month period (the “Incumbent Board”) cease to constitute at least a majority of the members of the Board; provided, however, that if the appointment or election (or nomination for election) of any new Board member was approved or recommended by a majority vote of the members of the Incumbent Board then still in office, such new member shall be considered as a member of the Incumbent Board; or

(d) Any transaction or transactions occurring within a 12-month period as a result of which any person is the “beneficial owner” (as defined in Rule 13d-3 under the Exchange Act), directly or indirectly, of securities of the Company representing at least 30% of the total voting power represented by the Company’s then outstanding voting securities.

For purposes of this Section 17.4, the term “person” shall have the same meaning as when used in Sections 13(d) and 14(d) of the Exchange Act but shall exclude (i) a trustee or other fiduciary holding securities under an employee benefit plan of the Company or of a Parent or Subsidiary and (ii) a corporation owned directly or indirectly by the stockholders of the Company in substantially the same proportions as their ownership of the Common Shares.

For purposes of SubSection (a) above, the term “Ownership Percentage” means the percentage of the voting power of the outstanding securities of (i) the continuing or surviving entity and (ii) any direct or indirect parent corporation of such continuing or surviving entity.

A transaction shall not constitute a Change in Control if its sole purpose is to change the state of the Company’s incorporation or to create a holding company that will be owned in substantially the same proportions by the persons who held the Company’s securities immediately before such transaction. In addition, a transaction shall not constitute a Change in Control unless such transaction also qualifies as an event under Treasury Regulation Section 1.409A-3(i)(5)(v) (change in the ownership of a corporation), Treasury Regulation Section 1.409A-3(i)(5)(vi) (change in the effective control of a corporation), or Treasury Regulation Section 1.409A-3(i)(5)(vii) (change in the ownership of a substantial portion of a corporation’s assets).

17.5 “Code” means the Internal Revenue Code of 1986, as amended.

17.6 “Committee” means the Compensation Committee of the Board, as further described in Article 2.

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17.7 “Common Share” means one share of the common stock of the Company.

17.8 “Company” means Ariba, Inc., a Delaware corporation.

17.9 “Consultant” means a consultant or adviser who provides bona fide services to the Company, a Parent, a Subsidiary or an Affiliate as an independent contractor.

17.10 “Employee” means a common-law employee of the Company, a Parent, a Subsidiary or an Affiliate.

17.11 “Exchange Act” means the Securities Exchange Act of 1934, as amended.

17.12 “Exercise Price,” in the case of an Option, means the amount for which one Common Share may be purchased upon exercise of such Option, as specified in the applicable Stock Option Agreement. “Exercise Price,” in the case of a SAR, means an amount, as specified in the applicable SAR Agreement, which is subtracted from the Fair Market Value of one Common Share in determining the amount payable upon exercise of such SAR.

17.13 “Fair Market Value” means the closing sales price (or the closing bid, if no sales were reported) of the Common Shares on the principal U.S. market for Common Shares on the applicable date or, if the applicable date was not a trading day, on the last trading day prior to the applicable date. If Common Shares are no longer traded on a public U.S. securities market, the Fair Market Value shall be determined by the Committee in good faith on such basis as it deems appropriate. The Committee’s determination shall be conclusive and binding on all persons.

17.14 “Involuntary Termination” shall have the meaning given such term in the agreement applicable to the Award or in any other agreement between the Company and the Participant.

17.15 “ISO” means an incentive stock option described in Section 422(b) of the Code.

17.16 “NSO” means a stock option not described in Sections 422 or 423 of the Code.

17.17 “Option” means an ISO or NSO granted under the Plan and entitling the holder to purchase Common Shares.

17.18 “Optionee” means an individual or estate holding an Option or SAR.

17.19 “Outside Director” means a member of the Board who is not an Employee.

17.20 “Parent” means any corporation (other than the Company) in an unbroken chain of corporations ending with the Company, if each of the corporations other than the Company owns stock possessing 50% or more of the total combined voting power of all classes

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of stock in one of the other corporations in such chain. A corporation that attains the status of a Parent on a date after the adoption of the Plan shall be considered a Parent commencing as of such date.

17.21 “Participant” means an individual or estate holding an Award.

17.22 “Plan” means this Ariba, Inc. 1999 Equity Incentive Plan, as amended from time to time.

17.23 “Restricted Share” means a Common Share awarded under the Plan.

17.24 “Restricted Stock Agreement” means the agreement between the Company and the recipient of a Restricted Share that contains the terms, conditions and restrictions pertaining to such Restricted Share.

17.25 “SAR” means a stock appreciation right granted under the Plan.

17.26 “SAR Agreement” means the agreement between the Company and an Optionee that contains the terms, conditions and restrictions pertaining to his or her SAR.

17.27 “Service” means service as an Employee, Outside Director or Consultant.

17.28 “Stock Option Agreement” means the agreement between the Company and an Optionee that contains the terms, conditions and restrictions pertaining to his or her Option.

17.29 “Stock Unit” means a bookkeeping entry representing the equivalent of one Common Share, as awarded under the Plan.

17.30 “Stock Unit Agreement” means the agreement between the Company and the recipient of a Stock Unit that contains the terms, conditions and restrictions pertaining to such Stock Unit.

17.31 “Subsidiary” means any corporation (other than the Company) in an unbroken chain of corporations beginning with the Company, if each of the corporations other than the last corporation in the unbroken chain owns stock possessing 50% or more of the total combined voting power of all classes of stock in one of the other corporations in such chain. A corporation that attains the status of a Subsidiary on a date after the adoption of the Plan shall be considered a Subsidiary commencing as of such date.

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