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                                                                    EXHIBIT 10.3

                                   ARIBA, INC.

                           1999 EQUITY INCENTIVE PLAN

        (AS MOST RECENTLY AMENDED AND RESTATED EFFECTIVE OCTOBER 4, 2001)

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                                TABLE OF CONTENTS

                                                                     Page

ARTICLE 1. INTRODUCTION .............................................   1

ARTICLE 2. ADMINISTRATION ...........................................   1
  2.1  Committee Composition ........................................   1
  2.2  Committee Responsibilities ...................................   1
  2.3  Committee for Non-Officer Grants .............................   1

ARTICLE 3. SHARES AVAILABLE FOR GRANTS ..............................   2
  3.1  Basic Limitation .............................................   2
  3.2  Annual Increase in Shares ....................................   2
  3.3  Additional Shares ............................................   2
  3.4  Dividend Equivalents .........................................   3

ARTICLE 4. ELIGIBILITY ..............................................   3
  4.1  Incentive Stock Options ......................................   3
  4.2  Other Grants .................................................   3

ARTICLE 5. OPTIONS ..................................................   3
  5.1  Stock Option Agreement .......................................   3
  5.2  Number of Shares .............................................   3
  5.3  Exercise Price ...............................................   3
  5.4  Exercisability and Term ......................................   3
  5.5  Effect of Change in Control ..................................   4
  5.6  Modification or Assumption of Options ........................   4
  5.7  Buyout Provisions ............................................   4

ARTICLE 6. PAYMENT FOR OPTION SHARES ................................   4
  6.1  General Rule .................................................   4
  6.2  Surrender of Stock ...........................................   4
  6.3  Exercise/Sale ................................................   5
  6.4  Exercise/Pledge ..............................................   5
  6.5  Promissory Note ..............................................   5
  6.6  Other Forms of Payment .......................................   5

ARTICLE 7. STOCK APPRECIATION RIGHTS ................................   5
  7.1  SAR Agreement ................................................   5
  7.2  Number of Shares .............................................   5
  7.3  Exercise Price ...............................................   5
  7.4  Exercisability and Term ......................................   5
  7.5  Effect of Change in Control ..................................   6
  7.6  Exercise of SARs .............................................   6
  7.7  Modification or Assumption of SARs ...........................   6

ARTICLE 8. RESTRICTED SHARES ........................................   6
  8.1  Restricted Stock Agreement ...................................   6


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  8.2  Payment for Awards ............................................  6
  8.3  Vesting Conditions ............................................  7
  8.4  Voting and Dividend Rights                                       7

ARTICLE 9. STOCK UNITS ...............................................  7
  9.1  Stock Unit Agreement ..........................................  7
  9.2  Payment for Awards ............................................  7
  9.3  Vesting Conditions ............................................  7
  9.4  Voting and Dividend Rights ....................................  7
  9.5  Form and Time of Settlement of Stock Units ....................  8
  9.6  Death of Recipient ............................................  8
  9.7  Creditors' Rights .............................................  8

ARTICLE 10. PROTECTION AGAINST DILUTION ..............................  8
  10.1  Adjustments ..................................................  8
  10.2  Dissolution or Liquidation ...................................  9
  10.3  Reorganizations ..............................................  9

ARTICLE 11. DEFERRAL OF AWARDS .......................................  9

ARTICLE 12. AWARDS UNDER OTHER PLANS. ................................ 10

ARTICLE 13. PAYMENT OF DIRECTOR'S FEES IN SECURITIES ................. 10
  13.1  Effective Date ............................................... 10
  13.2  Elections to Receive NSOs, Restricted Shares or Stock Units .. 10
  13.3  Number and Terms of NSOs, Restricted Shares or Stock Units ... 10

ARTICLE 14. LIMITATION ON RIGHTS ..................................... 10
  14.1  Retention Rights ............................................. 10
  14.2  Stockholders' Rights ......................................... 11
  14.3  Regulatory Requirements ...................................... 11

ARTICLE 15. WITHHOLDING TAXES ........................................ 11
  15.1  General ...................................................... 11
  15.2  Share Withholding ............................................ 11

ARTICLE 16. FUTURE OF THE PLAN ....................................... 11
  16.1  Term of the Plan ............................................. 11
  16.2  Amendment or Termination ..................................... 11

ARTICLE 17. LIMITATION ON PAYMENTS ................................... 12
  17.1  Scope of Limitation .......................................... 12
  17.2  Basic Rule ................................................... 12
  17.3  Reduction of Payments ........................................ 12
  17.4  Overpayments and Underpayments ............................... 13
  17.5  Related Corporations ......................................... 13

ARTICLE 18. DEFINITIONS .............................................. 13



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                                   ARIBA, INC.

                           1999 EQUITY INCENTIVE PLAN

                            ARTICLE 1. INTRODUCTION

     The Board adopted the Plan effective June 23, 1999. 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 incentive stock
options or nonstatutory stock options) 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 Committee shall administer the Plan. The
Committee shall consist exclusively of two or more directors of the Company, who
shall be appointed by the Board. In addition, the composition of the Committee
shall satisfy:

          (a) 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

          (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.

     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 and (d) make all other
decisions relating to the operation of 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  Committee for 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


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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
Options, SARs, Stock Units and Restricted Shares awarded under the Plan shall
not exceed (a) 30,123,034* plus (b) the shares remaining available for issuance
under the Predecessor Plan** plus (c) the additional Common Shares described in
Sections 3.2 and 3.3. The limitations of this Section 3.1 and Section 3.2 shall
be subject to adjustment pursuant to Article 10.

     3.2  Annual Increase in Shares. As of January 1 of each year, commencing
with the year 2000 and ending with the year 2005, the aggregate number of
Options, SARs, Stock Units and Restricted Shares that may be awarded under the
Plan shall automatically increase. For the year 2000, the aggregate number of
Common Shares that may be issued pursuant to the Plan shall automatically
increase by a number equal to the lesser of (a) 5% of the total number of Common
Shares of Stock then outstanding or (b) 8,000,000 shares. For the years 2001
through 2005, the aggregate number of Common Shares that may be issued pursuant
to the Plan shall automatically increase by a number equal to the lowest of (a)
5% of the total number of Common Shares then outstanding, (b) 20,000,000 shares
or (c) the number determined by the Board.

     3.3  Additional Shares. If Common Shares issued under this Plan or the
Predecessor Plan upon the exercise of Options are forfeited, then such Common
Shares shall again become available for Awards under this Plan. If Restricted
Shares issued under this Plan or the Predecessor Plan are forfeited, then such
Common Shares shall again become available for Awards under this Plan. If Stock
Units, Options or SARs are forfeited or terminate for any other reason before
being exercised, then the corresponding Common Shares shall again become
available for Awards 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 Awards 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 Awards under the Plan. The foregoing notwithstanding,
the aggregate number of Common Shares that may be issued under the Plan upon the
exercise of ISOs shall not be increased when Restricted Shares or other Common
Shares are forfeited.

---------------------------
* Reflects two-for-one stock splits effected November 16, 1999, and March 2,
2000, and automatic increases under Article 3.2 of 8,000,000 shares on January
1, 2000, and 12,523,034 shares on January 1, 2001.

** As of December 1, 2000, 4,329,403 shares remained eligible for issuance under
the Predecessor Plan.

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     3.4  Dividend Equivalents. Any dividend equivalents paid or credited under
the Plan shall not be applied against the number of Restricted Shares, Stock
Units, Options or SARs available for Awards, whether or not such dividend
equivalents are converted into Stock Units.

                             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
requirements set forth in section 422(c)(6) 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. A Stock Option Agreement may provide that a
new Option will be granted automatically to the Optionee when he or she
exercises a prior Option and pays the Exercise Price in the form described in
Section 6.2.

     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 any Optionee in a
single fiscal year of the Company shall not cover more than 8,000,000 Common
Shares, except that Options granted to a new Employee in the fiscal year of the
Company in which his or her Service as an Employee first commences shall not
cover more than 10,000,000 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; provided that the Exercise Price under an ISO shall in no event be less
than 100% of the Fair Market Value of a Common Share on the date of grant and
the Exercise Price under an NSO shall in no event be less than 85% of the Fair
Market Value of a Common Share on the date of grant. In the case of an NSO, a
Stock Option Agreement may specify an Exercise Price that varies in accordance
with a predetermined formula while the NSO is outstanding.

     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

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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 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 Assumption of Options. Within the limitations of the
Plan, the Committee may modify, extend or assume outstanding options or may
accept the cancellation of outstanding options (whether granted by the Company
or by another issuer) in return for the grant of new options for the same or a
different number of shares and at the same or a different exercise price. The
foregoing notwithstanding, 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.

                      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 as follows:

          (a) In the case of an ISO granted under the Plan, payment shall be
     made only pursuant to the express provisions of the applicable Stock Option
     Agreement. The Stock Option Agreement may specify that payment may be made
     in any form(s) described in this Article 6.

          (b) In the case of an NSO, the Committee may at any time accept
     payment in any form(s) described in this Article 6.

     6.2  Surrender of Stock. To the extent that this Section 6.2 is applicable,
all or any part of the Exercise Price may be paid by surrendering, or attesting
to the ownership of, Common Shares that are already owned by the Optionee. Such
Common Shares shall be valued at their Fair Market Value on the date when the
new Common Shares are purchased under the Plan. The Optionee shall not
surrender, or attest to the ownership of, Common Shares in payment of the
Exercise Price if such action would cause the Company to recognize

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compensation expense (or additional compensation expense) with respect to the
Option for financial reporting purposes.

     6.3  Exercise/Sale. To the extent that this Section 6.3 is applicable, 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.

     6.4  Exercise/Pledge. To the extent that this Section 6.4 is applicable,
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
pledge all or part of the Common Shares being purchased under the Plan to a
securities broker or lender approved by the Company, as security for a loan, and
to deliver all or part of the loan proceeds to the Company.

     6.5  Promissory Note. To the extent that this Section 6.5 is applicable,
all or any part of the Exercise Price and any withholding taxes may be paid by
delivering (on a form prescribed by the Company) a full-recourse promissory
note. However, the par value of the Common Shares being purchased under the
Plan, if newly issued, shall be paid in cash or cash equivalents.

     6.6  Other Forms of Payment. To the extent that this Section 6.6 is
applicable, 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.

                      ARTICLE 7. STOCK APPRECIATION RIGHTS

     7.1  SAR Agreement. Each grant of an SAR under the Plan shall be evidenced
by an 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 any Optionee in a
single calendar year shall in no event pertain to more than 8,000,000 Common
Shares, except that SARs granted to a new Employee in the fiscal year of the
Company in which his or her Service as an Employee first commences shall not
pertain to more than 10,000,000 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.
An SAR Agreement may specify an Exercise Price that varies in accordance with a
predetermined formula while the SAR is outstanding.

     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

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specify the term of the SAR. An 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. An 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. An 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 an SAR or thereafter, that such SAR shall become fully exercisable
as to all 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 an 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
surrender) of the Common Shares subject to the SARs exceeds the Exercise Price.
If, on the date when an SAR expires, the Exercise Price under such SAR is less
than 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.

     7.7  Modification or Assumption of SARs. Within the limitations of the
Plan, the Committee may modify, extend or assume outstanding SARs or may accept
the cancellation of outstanding SARs (whether granted by the Company or by
another issuer) in return for the grant of new SARs for the same or a different
number of shares and at the same or a different exercise price. The foregoing
notwithstanding, no modification of an 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. Subject to the following sentence, Restricted
Shares may be sold or awarded under the Plan for such consideration as the
Committee may determine, including (without limitation) cash, cash equivalents,
full-recourse promissory notes, past services and future services. To the extent
that an Award consists of newly issued Restricted Shares, the consideration
shall consist exclusively of cash, cash equivalents or past

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services rendered to the Company (or a Parent or Subsidiary) or, for the amount
in excess of the par value of such newly issued Restricted Shares, full-recourse
promissory notes, as the Committee may determine.

     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.

     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 the holders of Restricted Shares invest any cash dividends received 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.

     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

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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 a lump sum or in installments. 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. 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  Death of Recipient. Any Stock Units Award that becomes payable after
the recipient's death shall be distributed to the recipient's beneficiary or
beneficiaries. Each recipient of a Stock Units Award under the Plan shall
designate one or more beneficiaries for this purpose by filing the prescribed
form with the Company. A beneficiary designation may be changed by filing the
prescribed form with the Company at any time before the Award recipient's death.
If no beneficiary was designated or if no designated beneficiary survives the
Award recipient, then any Stock Units Award that becomes payable after the
recipient's death shall be distributed to the recipient's estate.

     9.7  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;

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

          (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 other reorganization, outstanding Awards shall be subject to the agreement of
merger or reorganization. Such agreement shall provide for (a) the continuation
of the outstanding Awards by the Company, if the Company is a surviving
corporation, (b) the assumption of the outstanding Awards by the surviving
corporation or its parent or subsidiary, (c) the substitution by the surviving
corporation or its parent or subsidiary of its own awards for the outstanding
Awards, (d) full exercisability or vesting and accelerated expiration of the
outstanding Awards or (e) settlement of the full value of the outstanding Awards
in cash or cash equivalents followed by cancellation of such Awards.

                         ARTICLE 11. DEFERRAL OF AWARDS

     The Committee (in its sole discretion) may permit or require a Participant
to:

          (a) Have cash that otherwise would be paid to such Participant as a
     result of the exercise of an SAR or the settlement of Stock Units credited
     to a deferred compensation account established for such Participant by the
     Committee as an entry on the Company's books;

          (b) Have Common Shares that otherwise would be delivered to such
     Participant as a result of the exercise of an Option or SAR converted into
     an equal number of Stock Units; or

          (c) Have Common Shares that otherwise would be delivered to such
     Participant as a result of the exercise of an Option or SAR or the
     settlement of Stock Units converted into amounts credited to a deferred
     compensation account established for such Participant by the Committee as
     an entry on the Company's books. Such amounts shall be determined by
     reference to the Fair

                                       9



<PAGE>

     Market Value of such Common Shares as of the date when they otherwise would
     have been delivered to such Participant.

A deferred compensation account established under this Article 11 may be
credited with interest or other forms of investment return, as determined by the
Committee. A Participant for whom such an account is established shall have no
rights other than those of a general creditor of the Company. Such an account
shall represent an unfunded and unsecured obligation of the Company and shall be
subject to the terms and conditions of the applicable agreement between such
Participant and the Company. If the deferral or conversion of Awards is
permitted or required, the Committee (in its sole discretion) may establish
rules, procedures and forms pertaining to such Awards, including (without
limitation) the settlement of deferred compensation accounts established under
this Article 11.

                      ARTICLE 12. 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.

              ARTICLE 13. PAYMENT OF DIRECTOR'S FEES IN SECURITIES

     13.1 Effective Date. No provision of this Article 13 shall be effective
unless and until the Board has determined to implement such provision.

     13.2 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 13 shall be filed with the Company on the prescribed form.

     13.3 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 14. LIMITATION ON RIGHTS

     14.1 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).


                                       10

<PAGE>

     14.2 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
and paying any required Exercise Price. 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.

     14.3 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 15. WITHHOLDING TAXES

     15.1 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 Company for the satisfaction of any withholding tax
obligations that arise in connection with 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.

     15.2 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.

                         ARTICLE 16. FUTURE OF THE PLAN

     16.1 Term of the Plan. The Plan, as set forth herein, shall become
effective on October 4, 2001. The Plan shall remain in effect until it is
terminated under Section 16.2, except that no ISOs shall be granted on or after
the 10th anniversary of the date when the Board adopted the most recent increase
in the number of Common Shares available under Article 3 that was approved by
the Company's stockholders.

     16.2 Amendment or Termination. The Board may, at any time and for any
reason, amend or terminate the Plan. 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. 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.


                                       11

<PAGE>

                       ARTICLE 17. LIMITATION ON PAYMENTS

     17.1 Scope of Limitation. This Article 17 shall apply to an Award only if:

          (a) The independent auditors most recently selected by the Board (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 17 than it was before the
     application of this Article 17; or

          (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 17 (regardless of the after-tax value of such Award to the
     Participant).

If this Article 17 applies to an Award, it shall supersede any contrary
provision of the Plan or of any Award granted under the Plan.

     17.2 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 17, 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.

     17.3 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, and the
Participant may then elect, in his or her sole discretion, 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
advise the Company in writing of his or her election within 10 days of receipt
of notice. If no such election is made by the Participant within such 10-day
period, 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. For purposes of this Article 17, present
value shall be determined in accordance with section 280G(d)(4) of the Code. All
determinations made by the Auditors under this Article 17 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.


                                       12

<PAGE>

     17.4 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 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.

     17.5 Related Corporations. For purposes of this Article 17, 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 18. DEFINITIONS

     18.1 "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.

     18.2 "Award" means any award of an Option, an SAR, a Restricted Share or a
Stock Unit under the Plan.

     18.3 "Board" means the Company's Board of Directors, as constituted from
time to time.

     18.4 "Change in Control" means:

          (a) The consummation of a merger or consolidation of the Company with
     or into another entity or any other corporate reorganization, if persons
     who were not stockholders of the Company immediately prior to such merger,
     consolidation or other reorganization own immediately after such merger,
     consolidation or other reorganization more than 50% of the voting power of
     the outstanding securities of each of (i) the continuing or surviving
     entity and (ii) any direct or indirect parent corporation of such
     continuing or surviving entity;

          (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, as a result of which
     fewer than two-thirds of the incumbent directors are directors who either
     (i) had been directors of the Company on the date 24 months prior to the
     date of


                                       13

<PAGE>

     the event that may constitute a Change in Control (the "original
     directors") or (ii) were elected, or nominated for election, to the Board
     with the affirmative votes of at least a majority of the aggregate of the
     original directors who were still in office at the time of the election or
     nomination and the directors whose election or nomination was previously so
     approved; or

          (d) Any transaction 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 50% of the
     total voting power represented by the Company's then outstanding voting
     securities. For purposes of this Paragraph (d), 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 stock of the Company.

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.

     18.5 "Code" means the Internal Revenue Code of 1986, as amended.

     18.6 "Committee" means a committee of the Board, as described in Article 2.

     18.7 "Common Share" means one share of the common stock of the Company.

     18.8 "Company" means Ariba, Inc., a Delaware corporation.

     18.9 "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. Service as a Consultant shall be considered employment
for all purposes of the Plan, except as provided in Section 4.1.

     18.10 "Employee" means a common-law employee of the Company, a Parent, a
Subsidiary or an Affiliate.

     18.11 "Exchange Act" means the Securities Exchange Act of 1934, as amended.

     18.12 "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 an 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.


                                       14

<PAGE>

     18.13 "Fair Market Value" means the market price of Common Shares,
determined by the Committee in good faith on such basis as it deems appropriate.
Whenever possible, the determination of Fair Market Value by the Committee shall
be based on the prices reported in The Wall Street Journal. Such determination
                                   -----------------------
shall be conclusive and binding on all persons.

     18.14 "Involuntary Termination" means the termination of the Participant's
Service by reason of:

          (a) The involuntary discharge of the Participant by the Company (or
     the Parent, Subsidiary or Affiliate employing him or her) for reasons other
     than Misconduct; or

          (b) The voluntary resignation of the Participant following (i) a
     change in his or her position with the Company (or the Parent, Subsidiary
     or Affiliate employing him or her) that materially reduces his or her level
     of responsibility, (ii) a reduction in his or her level of compensation
     (including base salary, fringe benefits and participation in bonus or
     incentive programs) or (iii) a relocation of his or her place of employment
     by more than 50 miles, but only if such change, reduction or relocation is
     effected by the Company without his or her consent.

     18.15 "ISO" means an incentive stock option described in section 422(b) of
the Code.

     18.16 "Misconduct" means (a) the commission of any act of fraud,
embezzlement or dishonesty by the Optionee or Participant, (b) any unauthorized
use or disclosure by such person of confidential information or trade secrets of
the Company (or any Parent or Subsidiary) or (c) any other intentional
misconduct by such person adversely affecting the business or affairs of the
Company (or any Parent or Subsidiary) in a material manner. The foregoing
definition shall not be deemed to be inclusive of all acts or omissions that the
Company (or any Parent or Subsidiary) may consider as grounds for the dismissal
or discharge of any Optionee or Participant or other person in the Service of
the Company (or any Parent or Subsidiary).

     18.17 "NSO" means a stock option not described in sections 422 or 423 of
the Code.

     18.18 "Option" means an ISO or NSO granted under the Plan and entitling the
holder to purchase Common Shares.

     18.19 "Optionee" means an individual or estate who holds an Option or SAR.

     18.20 "Outside Director" means a member of the Board who is not an
Employee. Service as an Outside Director shall be considered employment for all
purposes of the Plan, except as provided in Section 4.1.


                                       15

<PAGE>

     18.21 "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 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.

     18.22 "Participant" means an individual or estate that holds an Award.

     18.23 "Plan" means this Ariba, Inc. 1999 Equity Incentive Plan, as amended
from time to time.

     18.24 "Predecessor Plan" means the Company's 1996 Stock Plan.

     18.25 "Restricted Share" means a Common Share awarded under the Plan.

     18.26 "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.

     18.27 "SAR" means a stock appreciation right granted under the Plan.

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

     18.29 "Service" means service as an Employee, Outside Director or
Consultant.

     18.30 "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.

     18.31 "Stock Unit" means a bookkeeping entry representing the equivalent of
one Common Share, as awarded under the Plan.

     18.32 "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.

     18.33 "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.


                                       16