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                                                                 Exhibit 4.2

                             INKTOMI CORPORATION

                            OFFICER'S CERTIFICATE
                            ---------------------


     The undersigned, Randy Gottfried, Senior Vice President and Chief
Financial Officer of Inktomi Corporation, a Delaware corporation (the
"Company"), DOES HEREBY CERTIFY as follows:

     1. This Certificate is furnished to the Wells Fargo Shareowners Services
     (the "Rights Agent"), in connection with the execution and delivery of
     Amendment No. 1 (the "Amendment") to the Rights Agreement previously
     entered into between the Company and the Rights Agent dated as of
     August 10, 2000 (the "Rights Agreement").  Terms that are defined in the
     Rights Agreement and that are used but not defined herein shall have the
     meaning given to them in the Rights Agreement.


     2. The undersigned, Randy Gottfried, hereby certifies that he is a duly
     elected, qualified and acting officer of the Company, and as such is duly
     authorized and qualified to execute and deliver this Certificate on behalf
     of the Company.


     3. Pursuant to Section 27 of the Rights Agreement, prior to the
     Distribution Date, the Company and the Rights Agent shall, if the Company
     so directs, supplement or amend any provision of the Rights Agreement
     without the approval of any holders of certificates representing Common
     Shares.


     4. In light of the foregoing, the Amendment has been effected in compliance
     with the terms of Section 27 of the Rights Agreement.

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     IN WITNESS WHEREOF, the undersigned has hereunto executed this Certificate
as of the 22nd day of December, 2002.


                                      INKTOMI CORPORATION



                                        By:     /s/ RANDY GOTTFRIED
                                        Name:   Randy Gottfried
                                        Title:  Senior Vice President and
                                                Chief Financial Officer
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                AMENDMENT NO. 1 TO PREFERRED STOCK RIGHTS AGREEMENT


     AMENDMENT NO. 1 TO PREFERRED STOCK RIGHTS AGREEMENT, dated as of
December 23, 2002 (this "Amendment"), between Inktomi Corporation, a Delaware
corporation (the "Company"), and Wells Fargo Shareowners Services (the "Rights
Agent").


                                    RECITALS

     WHEREAS, the Company and the Rights Agent are parties to a Preferred Stock
Rights Agreement, dated as of August 10, 2000, between the Company and the
Rights Agent (the "Rights Agreement");

     WHEREAS, the Company, Yahoo! Inc., a Delaware corporation ("Parent"), and
December 2002 Acquisition Corp. ("Merger Sub"), a Delaware corporation and a
direct, wholly-owned subsidiary of Parent, are entering into an Agreement and
Plan of Merger, dated as of December 22, 2002 (the "Merger Agreement"), pursuant
to which, upon the terms and subject to the conditions set forth therein, Merger
Sub will merge with and into the Company (the "Merger"), the separate corporate
existence of Merger Sub will cease and the Company will continue as the
surviving corporation;

     WHEREAS, the board of directors of the Company (the "Board of Directors")
has approved the Merger Agreement and the Merger and the transactions
contemplated thereunder;

     WHEREAS, pursuant to Section 27 of the Rights Agreement, the Company may
amend the Rights Agreement in any respect without the approval of any holders of
Rights; and

     WHEREAS, the Board of Directors has determined that this Amendment is
necessary, desirable and in the best interests of the stockholders of the
Company.

         Accordingly, the parties hereto agree as follows:

     1. AMENDMENT TO SECTION 1(a).  Section 1(a) of the Rights Agreement is
hereby amended in its entirety to read as follows:

     "Acquiring Person" shall mean any Person who or which, together with all
Affiliates and Associates of such Person, shall be the Beneficial Owner of 15%
or more of the Common Shares then outstanding, but shall not include an Exempt
Person (as such term is hereinafter defined), the Company, any Subsidiary of the
Company or any employee benefit plan of the Company or of any Subsidiary of the
Company, or any entity holding Common Shares for or pursuant to the terms of any
such plan. Notwithstanding the foregoing, no Person shall be deemed to be an
Acquiring Person as the result of an acquisition of Common Shares by the Company
which, by reducing the number of shares outstanding, increases the proportionate
number of shares beneficially owned by such Person to 15% or more of the Common
Shares of the Company then outstanding; provided, however, that if a Person
shall become the Beneficial Owner of 15% or more of the Common Shares of the
Company then outstanding by reason of share purchases by the Company and shall,
after such share purchases by the Company, become the Beneficial Owner of any
additional Common Shares of the Company (other than pursuant to
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a dividend or distribution paid or made by the Company on the outstanding Common
Shares in Common Shares or pursuant to a split or subdivision of the outstanding
Common Shares), then such Person shall be deemed to be an Acquiring Person
unless upon becoming the Beneficial Owner of such additional Common Shares of
the Company such Person does not beneficially own 15% or more of the Common
Shares of the Company then outstanding. Notwithstanding the foregoing, (i) if
the Company's Board of Directors determines in good faith that a Person who
would otherwise be an "Acquiring Person," as defined pursuant to the foregoing
provisions of this paragraph (a), has become such inadvertently (including,
without limitation, because (A) such Person was unaware that it beneficially
owned a percentage of the Common Shares that would otherwise cause such Person
to be an "Acquiring Person," as defined pursuant to the foregoing provisions
of this paragraph (a), or (B) such Person was aware of the extent of the Common
Shares it beneficially owned but had no actual knowledge of the consequences of
such beneficial ownership under this Agreement) and without any intention of
changing or influencing control of the Company, and if such Person divested or
divests as promptly as practicable a sufficient number of Common Shares so that
such Person would no longer be an "Acquiring Person," as defined pursuant to the
foregoing provisions of this paragraph (a), then such Person shall not be deemed
to be or to have become an "Acquiring Person" for any purposes of this
Agreement; and (ii) if, as of the date hereof, any Person is the Beneficial
Owner of 15% or more of the Common Shares outstanding, such Person shall not be
or become an "Acquiring Person," as defined pursuant to the foregoing provisions
of this paragraph (a), unless and until such time as such Person shall become
the Beneficial Owner of additional Common Shares (other than pursuant to a
dividend or distribution paid or made by the Company on the outstanding Common
Shares in Common Shares or pursuant to a split or subdivision of the outstanding
Common Shares), unless, upon becoming the Beneficial Owner of such additional
Common Shares, such Person is not then the Beneficial Owner of 15% or more of
the Common Shares then outstanding.  Notwithstanding anything in this Agreement
to the contrary, Yahoo! Inc., a Delaware corporation ("Parent"), December 2002
Acquisition Corp., a Delaware corporation and a direct, wholly-owned subsidiary
of Parent ("Merger Sub"), and their affiliates and associates, shall not be
deemed to be an "Acquiring Person" solely by virtue of executing, or acquiring
Common Shares pursuant to, (i) that certain Agreement and Plan of Merger, dated
as of December 22, 2002, by and among the Company, Parent and Merger Sub (the
"Merger Agreement"), (ii) the Merger (as defined in the Merger Agreement),
(iii) the Voting Agreements (as defined in the Merger Agreement), (iv) the
consummation of other transactions contemplated in the Merger Agreement or the
Voting Agreements (as defined in the Merger Agreement), or pursuant to a
 transfer of such Common Shares to a direct or indirect wholly owned Subsidiary
of one or more such Persons (each of the foregoing, an "Exempt Event")."

     2. AMENDMENT TO SECTION 1(l).  Section 1(l) of the Rights Agreement is
hereby amended to add the following sentence at the end thereof:

        "No Exempt Event shall cause a Distribution Date."

     3. AMENDMENT TO SECTION 1(z).  Section 1(z) of the Rights Agreement is
hereby amended to add the following sentence at the end thereof:

        "No Exempt Event shall cause a Redemption Date."

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     4.  AMENDMENT TO SECTION 1(ee).  Section 1(ee) of the Rights Agreement is
hereby amended to add the following sentence at the end thereof:

        "No Exempt Event shall cause a Section 11(a)(ii) Trigger Date."

     5.  AMENDMENT TO SECTION 1(ff).  Section 1(ff) of the Rights Agreement is
hereby amended to add the following sentence at the end thereof:

        "No Exempt Event shall cause a Section 13 Event."

     6.  AMENDMENT TO SECTION 1(hh).  Section 1(hh) of the Rights Agreement is
hereby amended to add the following sentence at the end thereof:

        "No Exempt Event shall cause a Shares Acquisition Date."

     7.  AMENDMENT TO SECTION 1(oo).  Section 1(oo) of the Rights Agreement is
hereby amended to add the following sentence at the end thereof:

        "No Exempt Event shall cause a Triggering Event."

     8.  AGREEMENT AS AMENDED.  "Agreement" as used in the Agreement shall be
deemed to refer to the Rights Agreement as amended hereby, and all references to
the Agreement shall be deemed to include this Amendment.

     9.  EFFECTIVENESS.  This Amendment shall be deemed effective as of the date
hereof.  Except as amended hereby, the Rights Agreement shall remain in full
force and effect and shall be otherwise unaffected by this Amendment.

     10. SEVERABILITY.  If any provision, covenant or restriction of
this Amendment is held by a court of competent jurisdiction or other authority
to be invalid, illegal or unenforceable, the remainder of the terms,
provisions, covenants and restrictions of this Amendment shall remain in full
force and effect and shall in no way be effected, impaired or invalidated.

     11. GOVERNING LAW.  This Amendment shall be deemed to be a contract made
under the laws of the State of Delaware and for all purposes shall be governed
by, and construed in accordance with, the laws of such state applicable to
contracts to be made and performed entirely within such state.

     12. COUNTERPARTS.  This Amendment may be executed in any number of
counterparts, each of such counterparts shall for all purposes be deemed to be
an original, and all such counterparts shall together constitute but one and
the same instrument.


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     13. MISCELLANEOUS.  All capitalized terms in this Amendment, unless
otherwise defined herein, shall have the meaning ascribed to them in the Rights
Agreement.








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                EXECUTED as of the date set forth above.

                                        INKTOMI CORPORATION



                                             By:    /s/ RANDY GOTTFRIED
                                             Name:  Randy Gottfried
                                             Title: Senior Vice President and
                                                    Chief Financial Officer



                                             WELLS FARGO SHAREOWNERS SERVICES



                                             By:    /s/ JENNIFER L. LENO
                                             Name:  Jennifer L. Leno
                                             Title: Officer




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