<PAGE>

THIS WARRANT AND ANY SHARES ACQUIRED UPON THE EXERCISE OF THIS WARRANT HAVE NOT
BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE
TRANSFERRED, SOLD OR OTHERWISE DISPOSED OF EXCEPT PURSUANT TO AN EFFECTIVE
REGISTRATION STATEMENT UNDER SAID ACT OR ON OPINION OF COUNSEL SATISFACTORY TO
THE COMPANY THAT REGISTRATION IS NOT REQUIRED UNDER SAID ACT.

                                   ARIBA, INC.

                                     CLASS A

                          COMMON STOCK PURCHASE WARRANT

                                                       Mountain View, California
                                                                 January 1, 2000

         ARIBA, INC., a Delaware corporation (the "Company"), for value
received, hereby certifies that EDS CoNext, Inc. ("EDS CoNext"), or its
registered assigns, is entitled to purchase from the Company    [*]    duly
authorized, validly issued, fully paid and nonassessable shares (the
"Shares") of Common Stock of the Company, par value $.002 per share (the
"Common Stock"), at the purchase price per share of    [*]    (the "Initial
Warrant Price"), all subject to the terms, conditions and adjustments set
forth below in this Warrant.

         This Warrant is one of the Common Stock Purchase Warrants (the
"Warrants," such term to include any warrants issued in substitution therefor)
originally issued in connection with the execution and delivery of the Alliance
Agreement dated as of December 31, 1999 (as from time to time in effect, the
"Alliance Agreement") between the Company and EDS CoNext. Certain capitalized
terms used in this Warrant are defined in Section 13 hereof.

1.  VESTING OF WARRANTS.

         1.1 VESTING EVENTS AND AMOUNTS. This Warrant shall vest and become
exercisable only upon the occurrence of the following events (each, a "Vesting
Event") and only for the following number of shares of Common Stock set forth
opposite such event:

<TABLE>
<CAPTION>

                                                                               Shares of
                 Vesting Event                                               Common Stock
                 -------------                                               ------------
<S>                                                                          <C>
                      [*]                                                         [*]
                                                                                  [*]
                                                                                  [*]
                                                                                  [*]
                                                                                  [*]


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


<PAGE>

                      [*]                                                         [*]
                                                                                  [*]
                                                                                  [*]
                                                                                  [*]
                                                                                  [*]
                                                                                  [*]
</TABLE>

Notwithstanding the provisions of this Section 1.1, the aggregate number of
shares of Common Stock issuable upon exercise of this Warrant shall not
exceed the aggregate number of Shares set forth in the introductory paragraph
hereof. The number of shares of Common Stock set forth in subsections (a)
through (k) above shall be adjusted to the extent and in the same manner as
the aggregate number of Shares is adjusted under the provisions of Sections 4
and 5 hereof. For purposes of each of subsections (a), (b) and (c) through
(f) above,     [*]

         1.2 EFFECTIVENESS OF VESTING. This Warrant shall be vested as to the
number of shares of Common Stock as set forth in Section 1.1 above on the
date that the Vesting Event occurs (the "Vesting Date" with respect to such
Vesting Event).

         1.3 NOTICE OF VESTING. Following the occurrence of any Vesting
Event, but no sooner than the first day of the next proceeding fiscal quarter
of the Company, EDS CoNext shall give the Company written notice of the
Vesting Event and the Vesting Date, together with all necessary documentation
to establish the foregoing (the "Vesting Notice" with respect to such Vesting
Event).

         1.4 NOTICE OF OBJECTION. The Company shall have ten (10) Business
Days from the Vesting Notice having been given in accordance with Section 15
(the "Objection Notice Period") to give EDS CoNext written notice that the
Company objects to all or a portion of the vesting of this Warrant as set
forth in the Vesting Notice (the "Objection Notice"). Any portion of the
vesting set forth in the Vesting Notice as to which no objection is made
shall be immediately vested. Upon the giving of the Objection Notice with
regard to any portion of the vesting as to which an objection is made, the
Company and EDS CoNext will use reasonable efforts to resolve any objections.
If the Company and EDS CoNext are unable to resolve the dispute, the Company
and EDS CoNext will jointly select an accounting firm of national standing to
resolve the dispute. If the Company and EDS CoNext are unable to agree on the
choice of such an


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                    -2-
<PAGE>

accounting firm, they will select an accounting firm of national standing by
lot which has not provided services to either the Company or EDS CoNext
during the preceding twenty-four (24) months (the "Accountant") which shall
determine whether the Vesting Event has occurred. The Accountant shall
deliver to each of the Company and EDS CoNext its determination within ten
(10) Business Days after being selected, and the determination of the
Accountant shall be binding upon the Company and EDS CoNext. The expenses of
the Accountant shall be borne equally by the Company and EDS CoNext. Any
additional portion of the Warrant that shall vest as a result of the
agreement of the Company and EDS CoNext or the determination of the
Accountant shall be vested as of the Vesting Date upon such agreement or
determination.

         1.5 EXERCISE OF WARRANT FOLLOWING SALE OF THE COMPANY. In the event of
the consummation of any transaction which would result in the holders of Common
Stock or any shares of common stock received in exchange for the Common Stock
receiving cash or non-marketable securities, the Warrant, (i) as to that portion
of the Warrant that is then exercisable, shall be exercised prior to the
commencement of such transaction, and (ii)     [*]

2. EXPIRATION OF WARRANT. This Warrant, as to each portion thereof that vests
and becomes exercisable pursuant to Section 1, shall expire on the fifth
anniversary date of the Vesting Date for such exercisable portion of the
Warrant (the "Expiration Date"). The Warrant shall cease to vest upon the
termination of the Alliance Agreement.

3. EXERCISE OF WARRANT. This Warrant shall be exercisable only with respect
to Shares as to which this Warrant has vested and become exercisable pursuant
to the terms of Sections 1 and 3 hereof.

         3.1 MANNER OF EXERCISE. This Warrant may only be exercised by the
holder hereof, in accordance with the terms and conditions hereof, in whole
or in part with respect to any vested portion of the Warrant, into shares of
Common Stock, during normal business hours on any Business Day on or prior to
the Expiration Date with respect to such vested portion of the Warrant, by
surrender of this Warrant to the Company at its office maintained pursuant to
Section 12.2(a) hereof, accompanied by an exercise notice in substantially
the form attached to this Warrant (or a reasonable facsimile thereof) duly
executed by the holder, and the holder shall thereupon be entitled to receive
a number of duly authorized, validly issued, fully paid and nonassessable
shares of Common Stock (or Other Securities) equal to:

                           (a)  an amount equal to:

                                    (i) an amount equal to (x) the number of
                           shares of Common Stock (or Other Securities)
                           determined as provided in Sections 4 and 5 hereof


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                      -3-
<PAGE>

                           which the holder would be entitled to receive upon
                           exercise of this Warrant for the number of shares of
                           Common Stock designated in the exercise notice
                           MULTIPLIED BY (y) the Current Market Price of each
                           share of Common Stock (or Other Securities) so
                           receivable upon exercise

                                    MINUS

                                    (ii) an amount equal to (x) the number of
                           shares of Common Stock (without giving effect to any
                           adjustment thereof) designated in the exercise notice
                           MULTIPLIED BY (y) the Initial Warrant Price

                           DIVIDED BY

                           (b) the Current Market Price of each share of Common
                 Stock (or Other Securities);

         PROVIDED, HOWEVER, that the holder may not exercise this Warrant for
         shares of Common Stock (or Other Securities) until     [*]

         3.2 WHEN EXERCISE EFFECTIVE. Each exercise of this Warrant shall be
deemed to have been effected immediately prior to the close of business on the
Business Day on which this Warrant shall have been surrendered to the Company as
provided in Section 3.1 hereof, and, at such time, the Person or Persons in
whose name or names any certificate or certificates for shares of Common Stock
(or Other Securities) shall be issuable upon exercise as provided in Section 3.3
hereof shall be deemed to have become the holder or holders of record thereof.

         3.3 DELIVERY OF STOCK CERTIFICATES, ETC. As soon as practicable after
each exercise of this Warrant, in whole or in part, and in any event within
fifteen (15) Business Days thereafter, the Company at its expense (including the
payment by it of any applicable issue taxes) will cause to be issued in the name
of and delivered to the holder hereof or, subject to Section 10 hereof, as the
holder (upon payment by the holder of any applicable transfer taxes) may direct:

                           (a) a certificate or certificates (with appropriate
                  restrictive legends, as applicable) for the number of duly
                  authorized, validly issued, fully paid and nonassessable
                  shares of Common Stock (or Other Securities) to which the
                  holder shall be entitled upon exercise plus, in lieu of any
                  fractional share to which the holder would otherwise be
                  entitled, cash in an amount equal to the same fraction of the
                  Market Price per share on the Business Day immediately prior
                  to the date of exercise; and

                           (b) in case exercise is in part only, a new Warrant
                  of like tenor, dated the date hereof and calling in the
                  aggregate on the face thereof for the number of shares of
                  Common Stock equal (without giving effect to any adjustment
                  thereof) to the number of shares called for on the face of
                  this Warrant minus the number of shares designated by the
                  holder upon exercise as provided in Section 3.1 hereof.


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                      -4-
<PAGE>

         3.4 COMPANY TO REAFFIRM OBLIGATIONS. The Company will, at the time of
each exercise of this Warrant, upon the written request of the holder hereof,
acknowledge in writing its continuing obligation to afford to the holder all
rights (including without limitation any rights to registration, pursuant to the
Registration Agreement referred to in Section 9 hereof, of the shares of Common
Stock or Other Securities issued upon exercise) to which the holder shall
continue to be entitled after exercise in accordance with the terms of this
Warrant; PROVIDED, HOWEVER, that if the holder of this Warrant shall fail to
make a request, the failure shall not affect the continuing obligation of the
Company to afford the rights to such holder.

4. ADJUSTMENT OF COMMON STOCK ISSUABLE UPON EXERCISE.

         4.1 GENERAL; NUMBER OF SHARES; WARRANT PRICE. The number of shares of
Common Stock which the holder of this Warrant shall be entitled to receive upon
each exercise hereof shall be determined by multiplying the number of shares of
Common Stock which would otherwise (but for the provisions of this Section 4) be
issuable upon exercise, as designated by the holder hereof pursuant to Section
3.1 hereof, by the fraction of which (a) the numerator is the Initial Warrant
Price and (b) the denominator is the Warrant Price in effect on the date of such
exercise. The "Warrant Price" shall initially be the Initial Warrant Price,
shall be adjusted and re-adjusted from time to time as provided in this Section
4 and, as so adjusted or re-adjusted, shall remain in effect until a further
adjustment or re-adjustment thereof is required by this Section 4.

         4.2 TREATMENT OF STOCK DIVIDENDS, STOCK SPLITS, ETC. In case the
Company at any time or from time to time after the date hereof shall declare or
pay any dividend on the Common Stock payable in Common Stock, or shall effect a
subdivision of the outstanding shares of Common Stock into a greater number of
shares of Common Stock (by reclassification or otherwise than by payment of a
dividend in Common Stock), then, and in each case, subject to Section 4.4
hereof, the Warrant Price shall be reduced, concurrently with the dividend or
subdivision, to a price determined by multiplying the Warrant Price by a
fraction:

                           (a) the numerator of which shall be the number of
                  shares of Common Stock outstanding immediately prior to the
                  dividend or subdivision; and

                           (b) the denominator of which shall be the number of
                  shares of Common Stock outstanding immediately after the
                  dividend or subdivision.

         Additional shares of Common Stock shall be deemed to have been issued
and to be outstanding (a) in the case of any dividend, immediately after the
close of business on the record date for the determination of holders of any
class of securities entitled to receive the dividend, or (b) in the case of any
subdivision, at the close of business on the day immediately prior to the day
upon which the corporate action becomes effective. Additional shares of Common
Stock deemed to have been issued pursuant to this Section 4.2 shall be deemed to
have been issued for no consideration.

         4.3 ADJUSTMENTS FOR COMBINATIONS, ETC. In case the outstanding shares
of Common Stock shall be combined or consolidated, by reclassification or
otherwise, into a lesser number of


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                     -5-
<PAGE>

shares of Common Stock, the Warrant Price in effect immediately prior to the
combination or consolidation shall, concurrently with the effectiveness of
such combination or consolidation, be proportionately increased. Adjustment
under this Section 4.3 shall become effective at the close of business on the
day immediately prior to the day upon which the corporate action becomes
effective.

         4.4 MINIMUM ADJUSTMENT OF WARRANT PRICE. If the amount of any
adjustment of the Warrant Price required pursuant to this Section 4 would be
less than one-tenth (1/10) of one percent (1%) of the Warrant Price in effect at
the time of the adjustment is otherwise so required to be made, the amount shall
be carried forward and adjustment with respect thereto made at the time of and
together with any subsequent adjustment which, together with the amount and any
other amount or amounts so carried forward, shall aggregate at least one tenth
(1/10) of one percent (1%) of the Warrant Price.

5. ADJUSTMENTS FOR CONSOLIDATION, MERGER, SALE OF ASSETS, REORGANIZATION,
ETC. In case the Company after the date hereof (a) shall consolidate with or
merge into any other Person and shall not be the continuing or surviving
corporation following the consolidation or merger, or (b) shall permit any
other Person to consolidate with or merge into the Company and the Company
shall be the continuing or surviving Person but, in connection with the
consolidation or merger, the Common Stock or Other Securities shall be
changed into or exchanged for stock or other securities of any other Person
or cash or any other property, or (c) shall transfer all or substantially all
of its properties or assets to any other Person, or (d) shall effect a
capital reorganization or reclassification of the Common Stock or Other
Securities then, and in the case of each such transaction, proper provision
shall be made so that, upon the basis and the terms and in the manner
provided in this Warrant, the holder of this Warrant, upon the exercise
hereof at any time after the consummation of the transaction, shall be
entitled to receive (at the aggregate Warrant Price in effect at the time of
such consummation for all Common Stock or Other Securities issuable upon
exercise immediately prior to the consummation), in lieu of the Common Stock
or Other Securities issuable upon exercise prior to the consummation, the
greatest amount of securities, cash or other property to which the holder
would actually have been entitled as a stockholder upon such consummation if
the holder had exercised the rights represented by this Warrant (to the
extent then exercisable pursuant to Section 1) immediately prior thereto,
subject to adjustments (subsequent to the consummation) as nearly equivalent
as possible to the adjustments provided for in Sections 4 and 5 hereof.

6. NO DILUTION OR IMPAIRMENT. The Company will not, by amendment of its
certificate of incorporation or through any consolidation, merger,
reorganization, transfer of assets, dissolution, issue or sale of securities
or any other voluntary action, avoid or seek to avoid the observance or
performance of any of the terms of this Warrant, but will at all times in
good faith assist in the carrying out of all of the terms and in the taking
of all actions necessary or appropriate in order to protect the rights of the
holder of this Warrant. Without limiting the generality of the foregoing, the
Company (a) will not permit the par value of any shares of stock receivable
upon the exercise of this Warrant to exceed the amount payable therefor upon
exercise, (b) will take all actions necessary or appropriate in order that
the Company may validly and legally issue fully paid and nonassessable shares
of stock on the exercise of the Warrant and


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                     -6-
<PAGE>

(c) will not take any action which results in any adjustment of the Warrant
Price if the total number of shares of Common Stock (or Other Securities)
issuable after the action upon the exercise of the Warrant would exceed the
total number of shares of Common Stock (or Other Securities) then authorized
by the Company's certificate of incorporation and available for the purpose
of issuance upon exercise.

7. CHIEF FINANCIAL OFFICER'S REPORT AS TO ADJUSTMENTS. In the case of any
adjustment or re-adjustment in the shares of Common Stock (or Other
Securities) issuable upon the exercise of this Warrant, the Company at its
expense will promptly compute the adjustment or re-adjustment in accordance
with the terms of this Warrant and, if requested by the holder, cause its
Chief Financial Officer to certify the computation (other than any
computation of the fair value of property as determined in good faith by the
Board of Directors of the Company) and prepare a report setting forth the
adjustment or re-adjustment and showing in reasonable detail the method of
calculation thereof and the facts upon which the adjustment or re-adjustment
is based, including a statement of (a) the number of shares of Common Stock
outstanding or deemed to be outstanding and (b) the Warrant Price in effect
immediately prior to the deemed issuance or sale and as adjusted and
re-adjusted (if required by Section 4 hereof) on account thereof. The Company
will forthwith mail a copy of each report to each holder of a Warrant and
will, upon the written request at any time of any holder of a Warrant,
furnish to the holder a like report setting forth the Warrant Price at the
time in effect and showing in reasonable detail how it was calculated. The
Company will also keep copies of all reports at its office maintained
pursuant to Section 12.2(a) hereof and will cause them to be available for
inspection at the office during normal business hours upon reasonable notice
by any holder of a Warrant or any prospective purchaser of a Warrant
designated by the holder thereof.

8. REPRESENTATION AS TO NUMBER OF OUTSTANDING SHARES. The Company represents
and warrants to EDS CoNext that, as of December 7, 1999, there were issued
and outstanding 108,847,771 shares of Common Stock (after giving effect to
the stock dividend paid on December 17, 1999), including the number of shares
of Common Stock issuable upon the exercise of all outstanding options and
warrants, calculated using the treasury stock method. Other than the stock
dividend paid on December 17, 1999, from December 7, 1999 until the date
hereof, no event has occurred which would have resulted in any adjustment
pursuant to Sections 4 or 5 hereof.

9. REGISTRATION OF COMMON STOCK. The shares of Common Stock (and Other
Securities) issuable upon exercise of this Warrant shall constitute
Registrable Securities (as such term is defined in the Registration
Agreement). The original holder of this Warrant, and any valid transferees
thereof pursuant to the Registration Agreement, shall be entitled to all of
the benefits afforded to a holder of any Registrable Securities under the
Registration Agreement and such holder, by its acceptance of this Warrant,
agrees to be bound by and to comply with the terms and conditions of the
Registration Agreement applicable to the holder as a holder of Registrable
Securities. At any time when the Common Stock is listed on any national
securities exchange, the Company will, at its expense, obtain promptly and
maintain the approval for listing on each exchange, upon official notice of
issuance, any shares of Common Stock issued upon exercise of the then
outstanding Warrants and maintain the listing of the shares after their


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                     -7-
<PAGE>

issuance; and the Company will also list on such national securities exchange,
will register under the Exchange Act and will maintain the listing of any Other
Securities that at any time are issued upon exercise of the Warrants, if and at
the time that any securities of the same class shall be listed on a national
securities exchange by the Company.

10.  RESTRICTIONS ON TRANSFER.

         10.1 RESTRICTIVE LEGENDS. This Warrant and each Warrant issued upon
transfer or in substitution for this Warrant pursuant to Section 12, each
certificate for Common Stock (or Other Securities) issued upon the exercise of
any Warrant and each certificate issued upon the transfer of any such Common
Stock (or Other Securities) shall be transferable only upon satisfaction of the
conditions specified in this Section 10 and Section 12.4. Each of the foregoing
securities shall be stamped or otherwise imprinted with a legend reflecting the
restrictions on transfer set forth in Sections 10 and 12.4 hereof and any
restrictions required under the Securities Act.

         10.2 NOTICE OF PROPOSED TRANSFER, OPINION OF COUNSEL. Prior to any
transfer of any Restricted Securities which are not registered under an
effective registration statement under the Securities Act, the holder thereof
will give written notice to the Company of the holder's intention to effect a
transfer and to comply in all other respects with this Section 10.2. Each notice
(a) shall describe the manner and circumstances of the proposed transfer, and
(b) shall designate counsel for the holder giving the notice (who may be
in-house counsel for the holder). The holder giving notice will submit a copy
thereof to the counsel designated in the notice. The following provisions shall
then apply:

                                    (i) If in the opinion of counsel for the
                           holder reasonably satisfactory to the Company the
                           proposed transfer may be effected without
                           registration of Restricted Securities under the
                           Securities Act (which opinion shall state the basis
                           of the legal conclusions reached therein), the holder
                           shall thereupon be entitled to transfer the
                           Restricted Securities in accordance with the terms of
                           the notice delivered by the holder to the Company.
                           Each certificate representing the Restricted
                           Securities issued upon or in connection with any
                           transfer shall bear the restrictive legends required
                           by Section 10.1 hereof.

                                    (ii) If the opinion called for in (i) above
                           is not delivered, the holder shall not be entitled to
                           transfer the Restricted Securities until either (x)
                           receipt by the Company of a further notice from such
                           holder pursuant to the foregoing provisions of this
                           Section 10.2 and fulfillment of the provisions of
                           clause (i) above or (y) such Restricted Securities
                           have been effectively registered under the Securities
                           Act.

         Notwithstanding any other provision of this Section 10, no opinion of
counsel shall be necessary for a transfer of Restricted Securities by the holder
thereof to an Affiliate of a holder, if the transferee agrees in writing to be
subject to the terms hereof to the same extent as if the transferee were the
original Purchaser hereof and such transfer is permitted under applicable
securities laws.


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                      -8-
<PAGE>

         10.3 TERMINATION OF RESTRICTIONS. The restrictions imposed by this
Section 10 upon the transferability of Restricted Securities shall cease and
terminate as to any particular Restricted Securities (a) which Restricted
Securities shall have been effectively registered under the Securities Act, or
(b) when, in the opinions of both counsel for the holder thereof and counsel for
the Company, such restrictions are no longer required in order to insure
compliance with the Securities Act or Section 12 hereof. Whenever such
restrictions shall cease and terminate as to any Restricted Securities, the
holder thereof shall be entitled to receive from the Company, without expense
(other than applicable transfer taxes, if any), new securities of like tenor not
bearing the applicable legends required by Section 10.1 hereof.

11. RESERVATION OF STOCK, ETC. The Company will at all times reserve and keep
available, solely for issuance and delivery upon exercise of the Warrant, the
number of shares of Common Stock of each class (or Other Securities) from time
to time issuable upon exercise of the Warrant at the time outstanding. All
shares of Common Stock (or Other Securities) issuable upon exercise of the
Warrant shall be duly authorized and, when issued upon exercise, shall be
validly issued and, in the case of shares, fully paid and nonassessable.

12.  OWNERSHIP, TRANSFER AND SUBSTITUTION OF WARRANT.

         12.1 OWNERSHIP OF WARRANT. The Company may treat the person in whose
name this Warrant is registered on the register kept at the office of the
Company maintained pursuant to Section 12.2(a) hereof as the owner and holder
thereof for all purposes, notwithstanding any notice to the contrary, except
that, if and when any Warrant is properly assigned in blank, the Company may
(but shall not be obligated to) treat the bearer thereof as the owner of such
Warrant for all purposes, notwithstanding any notice to the contrary. Subject to
Section 10 hereof, this Warrant, if properly assigned, may be exercised by a new
holder without a new Warrant first having been issued.

         12.2  OFFICE; TRANSFER AND EXCHANGE OF WARRANT.

                           (a) The Company will maintain an office (which may be
                  an agency maintained at a bank) in Mountain View, California
                  where notices, presentations and demands in respect of this
                  Warrant may be made upon it. The office shall be maintained at
                  1565 Charleston Road, Mountain View, California 94043 until
                  the Company notifies the holders of the Warrant of any change
                  of location of the office.

                           (b) The Company shall cause to be kept at its office
                  maintained pursuant to Section 12.2(a) hereof a register for
                  the registration and transfer of the Warrant. The names and
                  addresses of holders of the Warrant, the transfers thereof and
                  the names and addresses of transferees of the Warrant shall be
                  registered in such register. The Person in whose name any
                  Warrant shall be so registered shall be deemed and treated as
                  the owner and holder thereof for all purposes of this Warrant,
                  and the Company shall not be affected by any notice or
                  knowledge to the contrary.


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                      -9-
<PAGE>

                           (c) Upon the surrender of this Warrant, properly
                  endorsed, for registration of transfer or for exchange at the
                  office of the Company maintained pursuant to Section 12.2(a)
                  hereof, the Company at its expense will (subject to compliance
                  with Section 10 hereof, if applicable) execute and deliver to
                  or upon the order of the holder thereof a new Warrant of like
                  tenor, in the name of such holder or as such holder (upon
                  payment by such holder of any applicable transfer taxes) may
                  direct, calling in the aggregate on the face thereof for the
                  number of shares of Common Stock called for on the face of the
                  Warrant so surrendered.

         12.3 REPLACEMENT OF WARRANT. Upon receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of the
Warrant and, in the case of any such loss, theft or destruction of the Warrant,
upon delivery of indemnity reasonably satisfactory to the Company in form and
amount or, in the case of any mutilation, upon surrender of the Warrant for
cancellation at the office of the Company maintained pursuant to Section 12.2(a)
hereof, the Company at its expense will execute and deliver, in lieu thereof, a
new Warrant of like tenor and dated the date hereof.

         12.4 RESTRICTIONS ON TRANSFER. In addition to the restrictions on
transfer set forth in Section 10 hereof, neither the Warrant nor any portion of
the Warrant may be transferred without the consent of the Company unless the
Warrant has vested and become exercisable in accordance with Section 1 hereof as
to that portion of the Warrant that is to be transferred.

13. DEFINITIONS. As used herein, unless the context otherwise requires, the
following terms have the following respective meanings:

         ACCOUNTANT:  As defined in Section 1.4 hereof.

         ACTUAL SPEND: [*]

         AFFILIATE:  Any Person holding more than 50% of the equity of an entity
or any majority-owned subsidiary of such entity.

         ALLIANCE AGREEMENT:  As defined in the introduction to this Warrant.

         ARIBA NETWORK:  The business-to-business e-commerce network operated by
Ariba that enables buyers and suppliers to automate transactions on the
Internet.

         BUSINESS DAY: Any day other than a Saturday or a Sunday or a day on
which commercial banking institutions in New York, New York are authorized by
law to be closed. Any reference to "days" (unless Business Days are specified)
shall mean calendar days.


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                      -10-
<PAGE>

         COMMISSION:  The Securities and Exchange Commission or any other
federal agency at the time administering the Securities Act.

         COMMON STOCK: As defined in the introduction to this Warrant and
including any stock into which the Common Stock shall have been changed or any
stock resulting from any reclassification of the Common Stock, and all other
stock of any class or classes (however designated) of the Company the holders of
which have the right, without limitation as to amount, either to all, or to a
share of the balance of, current dividends and liquidating dividends after the
payment of dividends and distributions on any shares entitled to preference.

         COMPANY: As defined in the introduction to this Warrant and including
any corporation which shall succeed to or assume the obligations of the Company
hereunder in compliance with Section 5 hereof.

         CONSORTIUM: A group of entities organized by EDS CoNext that desire to
pool their purchasing for certain products and services, whether existing on the
date hereof or subsequently organized.

         CURRENT MARKET PRICE: On any date specified herein, the average daily
Market Price during the period of the most recent ten (10) days, ending on and
including such date, on which the national securities exchanges or the national
market system of the NASD were open for trading, except that if no class of the
Common Stock is then listed or admitted to trading on a national securities
exchange or the national market system of the NASD, the Current Market Price
shall be the Market Price on such date.

         EDS CONEXT:  EDS Conext, Inc., its subsidiaries and assigns.

         EDS CONEXT CONSORTIUM MEMBER: An entity that [*]

         EXCHANGE ACT: The Securities Exchange Act of 1934, or any similar
federal statute, and the rules and regulations of the Commission thereunder, all
as the same shall be in effect at the time.

         EXPIRATION DATE:  As defined in Section 2 of this Warrant.

         INITIAL WARRANT PRICE:  As defined in the introduction to this Warrant.

         LARGE PARTICIPANT: A Participant with annual revenues, including
revenues of the consolidated entities for which it is performing purchasing
(determined in accordance with generally accepted accounting principles for
such Participant's most recent fiscal year), between [*] and [*]. Revenues of
consolidated entities shall not be included in the annual


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                      -11-
<PAGE>

revenues of a Participant to the extent that such revenues are included in
the annual revenues of any other Participant.

         MARKET PRICE: On any date specified herein, the amount per share of
Common Stock equal to (a) the closing price of the Common Stock on such date or,
if no such sale takes place on such date, the average of the closing bid and
asked prices thereof on such date, in each case as officially reported on the
principal national securities exchange on which the Common Stock is then listed
or admitted to trading, or (b) if the Common Stock is not then listed or
admitted to trading on a national securities exchange but is designated as a
national market system security by the NASD, the last closing price of the
Common Stock on such date, or (c) if there shall have been no trading on such
date or if the Common Stock is not so designated, the average of the closing bid
and asked prices of the Common Stock on such date as shown by the NASD automated
quotation system, or (d) if the Common Stock is not then listed or admitted to
trading on any national exchange or the national market system of the NASD, the
fair value thereof determined in good faith by the Board of Directors of the
Company as of a date which is within fifteen (15) days of the date as of which
the determination is to be made.

         MEDIUM PARTICIPANT: A Participant with annual revenues, including
revenues of the consolidated entities for which it is performing purchasing
(determined in accordance with generally accepted accounting principles for such
Participant's most recent fiscal year), of less than [*]. Revenues of
consolidated entities shall not be included in the annual revenues of a
Participant to the extent that such revenues are included in the annual revenues
of any other Participant.

         NASD:  The National Association of Securities Dealers, Inc.

         OBJECTION NOTICE:  As defined in Section 1.4 hereof.

         OBJECTION NOTICE PERIOD:  As defined in Section 1.4 hereof.

         OTHER SECURITIES: Any stock (other than Common Stock) and other
securities of the Company or any other person (corporate or otherwise) which the
holders of the Warrants at any time shall be entitled to receive, or shall have
received, upon the exercise of the Warrants, in lieu of or in addition to Common
Stock, or which at any time shall be issuable or shall have been issued in
exchange for or in replacement of Common Stock or Other Securities pursuant to
Section 5 hereof or otherwise.

         PARTICIPANT: An entity that meets all of the following requirements
(1) such entity has over [*] of annual revenues, as determined in accordance
with generally accepted accounting principles for such entity's most recent
fiscal year; (2) such entity has executed, either prior to or subsequent to
the date hereof, a Participant Agreement pursuant to which such entity [*](3)
such entity [*]


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                       12

<PAGE>

[*] and (4) such entity is [*]

         If within two years after an entity has been classified as a
Participant by satisfying the requirements of the preceding paragraph, such
entity shall cease to be considered a "Participant" for purposes of subsequent
Vesting Events if [*]

         In addition, notwithstanding the previous two paragraphs, an entity
that has executed, either prior to or subsequent to the date hereof, a
Participant Agreement with EDS CoNext pursuant to which the entity has joined a
Consortium shall be deemed a Participant if [*]

                  If there is a reasonable basis to conclude that an entity that
initially satisfied the Actual Spend requirements set forth above subsequently
ceased to satisfy such requirement for [*] the parties shall in good faith
discuss whether such an entity should continue to be considered a Participant
despite [*], provided that


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                       13

<PAGE>

[*]
         PARTICIPANT AGREEMENT:  An agreement whereby an entity agrees to
participate in a Consortium.

         PERSON:  A corporation, an association, a partnership, an organization,
a business, an individual, a government or political subdivision thereof or a
governmental agency.

         REGISTRATION AGREEMENT: The Registration Rights Agreement dated as of
December 31, 1999, between the Company and EDS CoNext, as from time to time in
effect.

         RESTRICTED SECURITIES: All of the following: (a) the Warrant and (b)
any shares of Common Stock (or Other Securities) which have been issued upon the
exercise of the Warrant and which are evidenced by a certificate or certificates
bearing the applicable legend or legends referred to in Section 10.1.

         SECURITIES ACT:  The Securities Act of 1933, or any similar federal
statute, and the rules and regulations of the Commission thereunder, all as the
same shall be in effect at the time.

         VERY LARGE PARTICIPANT: A Participant with annual revenues, including
revenues for the consolidated entities for which it is performing purchasing
(as determined in accordance with generally accepted accounting principles
for such Participant's most recent fiscal year) in excess of [*] Revenues of
consolidated entities shall not be included in the annual revenues of a
Participant to the extent that such revenues are included in the annual
revenues of any other Participant.

         VESTING DATE:  As defined in Section 1.2 hereof.

         VESTING EVENT:  As defined in Section 1.1 hereof.

         VESTING NOTICE:  As defined in Section 1.3 hereof.

         WARRANT PRICE:  As defined in Section 4.1 hereof.

         WARRANTS:  As defined in the introduction to this Warrant.

14. NO RIGHTS OR LIABILITIES AS STOCKHOLDER. Nothing contained in this Warrant
shall be construed as conferring upon the holder hereof any rights as a
stockholder of the Company or as imposing any obligation on the holder to
purchase any securities or as imposing any liabilities on such holder as a
stockholder of the Company, whether such obligation or liabilities are asserted
by the Company or by creditors of the Company.

15. NOTICES. Any notice or other communication in connection with this Warrant
shall be deemed to be given if in writing (or in the form of a facsimile)
addressed as hereinafter provided


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                       14

<PAGE>

and actually delivered at said address: (a) if to any holder of any Warrant,
at the registered address of such holder as set forth in the register kept at
the office of the Company maintained pursuant to Section 12.2(a) hereof, or
(b) if to the Company, to the attention of its Chief Financial Officer at its
office maintained pursuant to Section 12.2(a) hereof; PROVIDED, HOWEVER, that
the exercise of any Warrant shall be effective in the manner provided in
Section 3 hereof.

16. MISCELLANEOUS. This Warrant and any term hereof may be changed, waived,
discharged or terminated only by an instrument in writing signed by the party
against which enforcement of the change, waiver, discharge or termination is
sought. This Warrant shall be construed and enforced in accordance with and
governed by the laws of the State of Delaware. The section headings in this
Warrant are for purposes of convenience only and shall not constitute a part
hereof.

                          *      *      *      *     *
                            (Signature page follows)


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


                                      -15-
<PAGE>

         IN WITNESS WHEREOF, the Company has caused this Class A Common Stock
Purchase Warrant to be duly executed as of the date first above written

                                                ARIBA, INC.


                                                By: /s/ Edward P. Kinsey
                                                   -----------------------------

                                                Title: EVP, CFO
                                                      --------------------------


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


<PAGE>

                             FORM OF EXERCISE NOTICE

                [To be executed only upon conversion of Warrant]


To [ISSUER]

         The undersigned registered holder of the within Warrant hereby
irrevocably converts the Warrant pursuant to Section 3.1 of the Warrant with
respect to __________(1) shares of the Common Stock which the holder would be
entitled to receive upon the cash exercise hereof, and requests that the
certificates for the shares be issued in the name of, and delivered to, whose
address is


Dated:                                  ________________________________________
                                        (Signature must conform in all respects
                                        to name of holder as specified on the
                                        face of Warrant)

                                        ________________________________________
                                        (Street Address)

                                        ________________________________________
                                        (City)        (State)      (Zip Code)









_______________________
(1) Insert here the number of shares called for on the face of this Warrant (or,
in the case of a partial exercise, the portion thereof as to which this Warrant
is being exercised), in either case without making any adjustment of shares of
Common Stock or any other stock or other securities or property or cash which,
pursuant to the adjustment provisions of this Warrant, may be delivered upon
exercise. In the case of a partial exercise, a new Warrant or Warrants will be
issued and delivered, representing the unconverted portion of the Warrant, to
the holder surrendering the Warrant.


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.


<PAGE>

                               FORM OF ASSIGNMENT

                 [To be executed only upon transfer of Warrant]


         For value received, the undersigned registered holder of the within
Warrant hereby sells, assigns and transfers unto __________ the right
represented by the Warrant to purchase __________(1) shares of Common Stock of
[ISSUER] to which the Warrant relates, and appoints __________ Attorney to make
such transfer on the books of [ISSUER] maintained for the purpose, with full
power of substitution in the premises.


Dated:                                  ________________________________________
                                        (Signature must conform in all respects
                                        to name of holder as specified on the
                                        face of Warrant)

                                        ________________________________________
                                        (Street Address)

                                        ________________________________________
                                        (City)        (State)      (Zip Code)
Signed in the presence of:



                                        ________________________________________
                                        (Signature of Transferee)

                                        ________________________________________
                                        (Street Address)

                                        ________________________________________
                                        (City)        (State)      (Zip Code)
Signed in the presence of:





_______________________
(1) Insert here the number of shares called for on the face of this Warrant (or,
in the case of a partial exercise, the portion thereof as to which this Warrant
is being exercised), in either case without making any adjustment of shares of
Common Stock or any other stock or other securities or property or cash which,
pursuant to the adjustment provisions of this Warrant, may be delivered upon
exercise. In the case of a partial exercise, a new Warrant or Warrants will be
issued and delivered, representing the unexercised portion of the Warrant, to
the holder surrendering the Warrant.


* Represents confidential information for
  which Ariba, Incorporated is seeking confidential
  treatment with the Securities and Exchange Commission.