<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 C-2

                          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 AMOUNTS AND DATES. The Revenue Targets, the maximum
number of Shares as to which the Warrant may vest and become exercisable for
each Target Year, and the Vesting Date for such Shares are as follows:

<TABLE>
<CAPTION>
                                                       Maximum Number
             Target Year        Revenue Target        of Shares Vested         Vesting Date
             -----------        --------------        ----------------         ------------
<S>                             <C>                   <C>                      <C>
                [*]                  [*]                    [*]                       [*]
</TABLE>

This Warrant will vest and become exercisable on an annual basis as of the
Vesting Date and become exercisable for the following which occur during such
Target Year: (i) upon the


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

<PAGE>

Company receiving Revenues equal to [*] of the Revenue Target for the
corresponding Target Year, this Warrant shall vest and become exercisable for
[*] of the maximum number of Shares as to which the Warrant may vest and
become exercisable for such Target Year as of the Vesting Date for such
Target Year (based on the percentage set forth above), and (ii) in the event
the Company receives Revenues in excess of [*] of such Revenue Target, this
Warrant shall vest and become exercisable for [*] of the maximum number of
Shares as to which the Warrant may vest and become exercisable for such
Target Year (based on the percentage set forth above). The number of shares
of Common Stock set forth 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.

         1.2 [*]

         1.3 [*]

         1.4 NOTICE OF VESTING. Within sixty (60) days after the end of each
of the Target Years and the Cumulative Make-Up Period, EDS CoNext will
prepare and deliver to the Company (a) a revenue statement, prepared in
accordance with generally accepted accounting principles, setting out the
Revenue for the period, together with all appropriate supporting
documentation and (b) a computation of the number of Shares that have vested
and become exercisable as of the Vesting Date with respect to such period in
accordance with the terms hereof (the "Vesting Notice").

         1.5 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 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 the Revenue for the period. 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


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


                                      -2-

<PAGE>

the agreement of the Company and EDS CoNext or the determination of the
Accountant shall be vested as of the Vesting Date for such shares upon such
agreement or determination.

         1.6 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 only be exercisable with respect
to Shares as to which the 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
                           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


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


                                      -3-

<PAGE>

                                    (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.

         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


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


                                      -4-

<PAGE>

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 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.


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


                                      -5-

<PAGE>

         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 (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.


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


                                      -6-
<PAGE>

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
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.


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


                                      -7-
<PAGE>

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.

         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


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


                                      -8-
<PAGE>

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.

                           (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


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


                                      -9-
<PAGE>

                  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.

         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
the Company 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.

         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.


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


                                      -10-
<PAGE>

         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.

         [*]  As defined in Section 1.3 hereof.

         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 FRAME AGREEMENTS: The agreements entered into between EDS
CoNext and suppliers pursuant to which such suppliers agree to provide goods
and/or services to one or more Consortia.

         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.

         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, (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.


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


                                     -11-

<PAGE>

         NASD:  The National Association of Securities Dealers, Inc.

         OBJECTION NOTICE:  As defined in Section 1.5 hereof.

         OBJECTION NOTICE PERIOD:  As defined in Section 1.5 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 [*]

         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.

         REVENUE TARGET:  The respective level of Revenues with respect to a
Target Year as set forth in Section 1.1.

         REVENUES: The aggregate amount of fee revenue described below that
are received by the Company in accordance with the Alliance Agreement:

                                      [*]


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


                                     -12-

<PAGE>

                                      [*]

                                      [*]

                                      [*]

         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.

         TARGET YEAR: The [*] twelve-month periods commencing on January 1,
2000 and ending on each of the [*] subsequent anniversaries of such date.

         VESTING DATE:  The respective date of vesting with respect a Target
Year as set forth in Section 1.1.

         VESTING NOTICE:  As defined in Section 1.4 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 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.


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


                                     -13-

<PAGE>

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.


                                     -14-

<PAGE>


         IN WITNESS WHEREOF, the Company has caused this Class C-2 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.