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EXHIBIT 10.9

          FIRST AMENDMENT TO FIRST AMENDED AND RESTATED LEASE AGREEMENT

      THIS FIRST AMENDMENT TO FIRST AMENDED AND RESTATED LEASE AGREEMENT
("AMENDMENT") is executed as of May 31, 2001 ("EFFECTIVE DATE"), by and between
PARKSIDE TOWERS CO-TENANCY, a tenancy in common between: Gateway Phoenix
Associates, L.P., a California limited partnership, and 5990 Sepulveda
Associates, L. P., a California limited partnership, (collectively, "Landlord"),
and INKTOMI CORPORATION, a Delaware corporation ("TENANT").

                                    Recitals

      A. Pursuant to the terms of the written First Amended and Restated Lease
Agreement between Landlord and Tenant, dated for identification purposes as of
March 10, 2000 (the "ORIGINAL LEASE"), Landlord has agreed to construct the
Project and Tenant has agreed to lease from Landlord all the space in the
Project comprising approximately 381,050 rentable square feet of office space
(which number excludes approximately 17,410 rentable square feet currently
designated for retail use), which would make the Project essentially a
single-tenant building. Capitalized terms not defined in this Amendment shall
have the meanings given them in the Original Lease. As used in this First
Amendment, "LEASE" shall mean the Original Lease, as amended by this First
Amendment.

      B. Landlord has received approval of the Base Building Plans for the Base
Building Work (as defined in the Original Lease) from the City of Foster City,
has hired Webcor Construction, Inc., dba Webcor Builders ("WEBCOR"), as the
general contractor therefor, and has commenced the construction thereof.
Landlord has approved Tenant's proposed Space Planner for the Tenant
Improvements. Landlord has already entered into a contract with WCP Services,
Inc., dba Commercial Interior Contractors ("CIC"), as the general contractor, to
construct and install the Tenant Improvements and CIC has prepared an initial
Construction Schedule for the Tenant Improvement work.

      C. Tenant desires to have certain major changes and additions made to the
Base Building Work and to have the Project developed and constructed
accordingly. Landlord is willing to accommodate Tenant's desires so long as
Tenant adequately and timely compensates Landlord for all the costs and delays
that arise due to any such changes and additions, whether or not known or
foreseeable at this time by Landlord.

      D. Landlord and Tenant desire to amend the Original Lease, inter alia, (i)
to provide for the changes and additions set forth herein to be made to the Base
Building Work (and to the Tenant Improvements, if so effected), (ii) to set
forth Tenant's obligations to pay all costs in connection with such changes and
additions and for the restoration of the Project due to such changes and
additions when Tenant reduces its occupancy or vacates the Premises to convert
same to a multi-tenant building, and (iii) to otherwise provide for all impacts
that such changes


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and additions may have on the Original Lease and the economic terms thereof, all
upon and subject to the terms and conditions set forth in this Amendment.

      NOW THEREFORE, in consideration of the foregoing recitals and the mutual
agreements of the parties herein, Landlord and Tenant hereby agree as follows:

      1. Changes and Additions to Base Building Work. Tenant hereby proposes to
have Landlord make and incorporate those changes and additions to the Base
Building Work which are set forth in Attachment A hereto ("BASE BUILDING
CHANGES"). Base Building Change items on Attachment A may be deleted, added or
modified hereafter by written confirmation of the parties without needing to
execute a formal amendment of this Amendment or the Lease. Tenant acknowledges
that implementing the Base Building Changes has required and will require (i)
significant design and engineering work, (ii) extensive consultation among
Tenant, Tenant's Space Planner and other consultants, Landlord, Landlord's
general contractor, subcontractors and suppliers, and the City, (iii)
governmental approvals therefor, (iv) amendments and/or change orders to
contracts with contractors and consultants, including without limitation, Webcor
and CIC, and (v) legal drafting, review and approval of documents, and that such
changes may also require or lead to changes being made to the Space Plan and/or
the Tenant Improvements (collectively, the "REDESIGN EFFORT"). The Redesign
Effort undertaken to date has resulted, and continued efforts will result, in
the preparation of a revised set of Base Building Plans (including drawings,
specifications and construction schedules) for submittal to the City for
approval and for use in obtaining estimates and bids. In the future, the
Redesign Effort may result in changes to the Construction Documents for the
Tenant Improvements (including drawings, specifications and construction
schedules applicable thereto), and may require the acceptance of an additional
set of conditions to governmental approval(s) to allow implementation of the
Base Building Changes and Tenant Improvements before the actual changes and
improvements can be incorporated into the Project. Landlord and Tenant agree
that the Base Building Changes and any resulting Changes in the Tenant
Improvements shall be subject to Landlord's consent which consent shall not be
unreasonably withheld so long as any such Change is not likely to (i) effect the
structural elements of the Project, (ii) impair Landlord's ability, or
significantly increase the costs, to convert or prepare the Project for
multi-tenant use when necessary, (iii) reduce the value of the Project, or (iv)
require concessions, exactions, mitigation measures or other conditions which
are unacceptable to Landlord to be imposed on the Project by the City or other
governmental agency in connection with obtaining all necessary governmental
approvals for any of the foregoing Changes, but if any such Change is likely to
result in any of the foregoing, Landlord may withhold or condition its consent
in its sole and absolute discretion. Tenant further acknowledges that it
previously approved the acquisition or substitution of certain specific HVAC,
electrical and structural steel items also identified and highlighted in
Attachment A along with the costs therefor.

      2. Tenant's Responsibility for Base Building Changes Costs; New
Construction Schedules. Tenant acknowledges that the Base Building Changes were
initiated at its request and therefore, pursuant to the Original Lease, Tenant
is responsible for all costs and delays caused thereby, whether or not now known
or foreseeable by Landlord, including, without limitation, all costs reasonably
incurred by Landlord (i) for the Redesign Effort (subject to the specific

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limitation on certain legal fees incurred by Landlord as provided in Section 4
below), (ii) for the acquisition, fabrication, installation and construction of
the Base Building Changes and of any Changes to the Tenant Improvements in
connection therewith, along with additional contractor general conditions,
overhead and fee, and (iii) for canceling or changing items already ordered,
returning items already shipped or delivered, removing or changing components of
the Project already constructed or installed, and undertaking any special
construction or installation to make way for the Base Building Changes (items
under subclauses (ii) and (iii) collectively, "HARD COSTS"), and (iv) Landlord's
development management and overhead costs in the amount of seven and one half
percent (7.5%) of the total costs for the Redesign Effort and the Hard Costs
("LANDLORD'S OVERHEAD"). In connection with the Redesign Effort and Tenant's
review and approval of the Hard Costs, Landlord has previously submitted to
Tenant a revised schedule for construction of the Base Building Work (which
incorporates the effect on scheduling from the Base Building Changes) and the
Premises Construction Schedule referenced in Section 2.2(a) of the Construction
Rider (together, the "REVISED CONSTRUCTION SCHEDULES"). A copy of the Revised
Construction Schedules is attached hereto as Attachment B. Tenant hereby
approves the Revised Construction Schedules attached hereto.

      3. Continuation and Completion of Redesign Effort. To the extent that
Landlord disapproves a proposed Base Building Change or Tenant disapproves the
estimated Hard Cost (as provided below) for a Base Building Change, Landlord and
Tenant shall continue the Redesign Effort to value engineer the particular item,
to change the scope of the Base Building Changes, or to adjust other elements of
the Base Building or the Project to address Landlord's and Tenant's concerns,
but all such further Revisions Effort shall be at Tenant's cost payable as
provided below. Landlord and Tenant agree to continue to work together in the
Redesign Effort in good faith and on an expeditious basis to resolve all issues,
to obtain all necessary governmental approvals, to obtain all necessary cost
estimates, bids and contracts, and to reach agreement on the Hard Costs for the
Building Changes to incorporate the Base Building Changes into the Project;
provided however, Tenant must approve or disapprove all Hard Costs for the
Construction Effort (as defined below) by the Effective Date ("REDESIGN EFFORT
CUT-OFF DATE"). To the extent that the Hard Costs for any component of the Base
Building Changes are not approved by Tenant by the Redesign Effort Cut-off Date,
Landlord shall be authorized to proceed with the Base Building Improvements
incorporating only those components of the Base Building Changes so approved by
Tenant.

      4. Payment of Costs. (a) Landlord agrees to proceed with (i) the Redesign
Effort on condition that Tenant reimburse Landlord all costs incurred in
undertaking the Redesign Effort (subject to the specific limitation on certain
legal fees reasonably incurred by Landlord as provided below), plus Landlord's
Overhead thereon, and (ii) constructing the approved Base Building Changes on
condition that Tenant reimburse Landlord all costs incurred in connection
therewith, plus Landlord's Overhead thereon, all as provided below. Tenant
covenants to pay all such costs to Landlord as provided below.

      (b) Landlord agrees that Tenant shall have the right to reasonably approve
the final estimated costs for the Hard Costs for each line item of the Base
Building Changes ("ESTIMATED BUDGET"), before Landlord directs that same be
implemented. Upon Tenant's approval of the

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Estimated Budget, Landlord shall issue such Change Orders or enter into such
contracts (or amendments thereto) as are necessary to cause such Change to be
acquired, fabricated, constructed and installed ("CONSTRUCTION EFFORT").
Landlord agrees to provide Tenant the opportunity to participate in the
negotiations with the contractor and subcontractors concerning all Hard Costs,
and to verify actual costs incurred for all Redesign Efforts and Hard Costs, but
such participation in negotiations and verification shall not constitute an
additional approval right of Tenant over the costs incurred for the Construction
Effort.

      (c) Tenant shall pay to Landlord twenty-five percent (25%) of the total
estimated costs in the Estimated Budget (excluding any contingency amount) for
the approved Base Building Changes, including, without limitation, (i) all costs
for the Redesign Effort (subject to the specific limitation on certain legal
fees incurred by Landlord as provided below), (ii) all Hard Costs for Base
Building Changes approved by Landlord and Tenant, and (iii) Landlord's Overhead
thereon, within ten (10) days after the Effective Date and Landlord's delivery
to Tenant of Landlord's invoice or statement therefor together with reasonable
supporting documentation from the contractor and subcontractors (the "BASE
BUILDING CHANGES DEPOSIT").

      (d) Tenant shall pay to Landlord within ten (10) Business Days of
Landlord's delivery to Tenant of Landlord's periodic invoice or statement
therefor (together with reasonable supporting documentation from the contractor
and subcontractors), the actual costs for the approved Base Building Changes
(and all costs for any Tenant Improvements which were incurred or committed to
by Landlord prior to the Effective Date) as they are incurred or ordered by
Landlord (including, without limitation, Landlord's Overhead thereon)
(collectively, the "TOTAL BASE BUILDING CHANGES RELATED COSTS"). At such time
and so long as the unbilled portion of the estimated costs for the Base Building
Changes (plus a prudent, reasonable contingency therefor) is equal to or less
than the Base Building Changes Deposit, subsequent invoices for the remaining
Base Building Changes shall apply a portion of the Base Building Changes Deposit
as a credit against the Total Base Building Related Costs in said invoice,
provided that, at all times, the Base Building Changes Deposit held by Landlord
is equal to the remaining unbilled estimated costs (plus a prudent, reasonable
contingency therefor) until such time as the Base Building Changes have been
totally completed and Tenant has fully paid to Landlord all the Total Base
Building Changes Related Costs. If through the foregoing process and upon
completion of the Base Building Changes, Tenant ends up having paid more than
the Total Base Building Changes Related Costs, Landlord shall refund the excess
to Tenant within ten (10) Business Days of Landlord's receipt of Tenant's final
payment therefor. The amount of legal fees incurred by Landlord in connection
with the preparation, negotiation and execution of this Amendment which may be
included in the costs of the Redesign Effort which resulted in the list of and
estimated costs for the Base Building Changes which have been approved by Tenant
as of the Effective Date, shall not exceed $25,000.

      5. Revised Premises. Attachment C hereto depicts the approximate intended
revised configuration and location of the Premises taking into account the Base
Building Changes listed in Attachment A (assuming that Landlord and Tenant
approve all such Changes and any resulting Changes in the Tenant Improvements)
if same were incorporated into the Project. When the Base Building (including
the Base Building Changes made pursuant to this Amendment) and the Tenant
Improvements (including any Changes to the Tenant Improvements resulting from
said


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Base Building Changes) have been Substantially Completed, Attachment C hereto
will be revised, if necessary, to depict the final approximate configuration and
location of the Premises, and thereafter, such revised Attachment C shall be
substituted for Exhibit A to the Original Lease as a depiction of the
approximate configuration and location of the Premises.

      6. Rentable Area Unchanged; Subsequent Adjustments. Landlord and Tenant
agree that notwithstanding any changes and additions to the Base Building Work
(and to the Space Plan and/or Tenant Improvements resulting from said Base
Building Changes, if any) pursuant to this Amendment, the total Rentable Area of
the Premises shall remain unchanged due to the installation of the Base Building
Changes and that if and to the extent that any usable area for office or other
permitted uses is reduced to accommodate the Base Building Changes, the
Rentable/Usable Ratio for the Premises (as defined under the BOMA Standard)
shall be adjusted so that the total Rentable Area of the Premises remains
unchanged. Notwithstanding anything to the contrary in the Original Lease, and
without impliedly creating any right of Tenant to return all or any portion of
the Premises to Landlord prior to the Expiration Date other than as already
expressly provided in the Original Lease, in the event that Tenant vacates all
or any portion of a particular floor in the Premises where certain mechanical or
telecom areas or rooms may be constructed or enlarged as part of the Base
Building Changes, but where such areas or rooms need to remain and continue to
be used to service Tenant's remaining occupancy in the Project, the
Rentable/Usable Ratio for the remaining Premises shall be further adjusted to
account for the fact that such mechanical and telecom rooms cannot be reduced in
size to make more space available in the Project for multi-tenant leasing as
office or other uses.

      7. Rent Commencement Dates. Due to the fact that Tenant was the party who
requested the Base Building Changes, Tenant agrees that all Partial Rent
Commencement Dates and the Final Rent Commencement Date shall be calculated as
if Tenant had not requested any of the Base Building Changes, subject to the
following provisions in this Section 7. Landlord and Tenant acknowledge that
some work on the Project has been able to continue notwithstanding that Tenant
has requested the Base Building Changes. As of May 1, 2001, Landlord and Tenant
agree that there have occurred thirty (30) days of Tenant Delay due to the
Redesign Effort for the Base Building Changes ("INITIAL TENANT DELAY"). To
compensate Landlord as liquidated damages for such Initial Tenant Delay, Tenant
agrees to pay to Landlord on each Partial Rent Commencement Date an amount equal
to thirty (30)-days Base Rent for the applicable floor of the Premises at the
initial rate set forth in the Basic Lease Information ("INITIAL TENANT DELAY
PAYMENT"), not as prepaid rent but in addition to all other sums which are
required to be paid by Tenant under the Lease as of such date, including without
limitation, monthly Base Rent for the Premises. Landlord and Tenant hereby agree
that the foregoing Initial Tenant Delay Payment is a reasonable sum to
compensate Landlord for such delay under the circumstances as of May 1, 2001.
Furthermore, due to the extensive nature of the Base Building Changes, the
uncertainty and inability of either party to accurately forecast or estimate the
time and effort involved in completing all Redesign Efforts (especially in light
of Landlord's and Tenant's rights to accept or reject components of the Base
Building Changes and Tenant's rights to approve the Hard Costs), and in reliance
on the good faith expeditious efforts that Landlord has undertaken to date in
the Redesign Effort, Tenant agrees that to the extent that the Project is
further delayed from and after May 1, 2001, due to any Redesign Efforts, the
Construction Efforts and/or deferral of the start or


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continuation of any Tenant Improvements, such delays shall be considered Tenant
Delays. In addition, Landlord and Tenant agree that Landlord's consent to
undertake further Base Building Changes and any resulting Changes to the Tenant
Improvements, and/or commencement or continuation of the Tenant Improvements,
shall be further conditioned upon Tenant's acceptance of the number of
additional days of Tenant Delay that Landlord estimates will result from the
Construction Effort from the dates set forth in the Revised Construction
Schedules attached (subject to the extent of any actual impact upon substantial
completion of the Base Building), which schedules already account for the
Initial Tenant Delay. Subject to all of the foregoing, the Partial Rent
Commencement Dates and the Final Rent Commencement Date shall be calculated as
provided in the Original Lease.

      8. Building Systems; Service Failure. (a) One component of the Base
Building Changes is the substitution of 21KV primary electrical service to the
Project for more normal secondary service, and to that end the installation by
PG&E of a 21KV main electrical service extension to the Project ("PRIMARY
ELECTRICAL SERVICE"). Landlord shall arrange for PG&E to extend to the Buildings
and install Primary Electrical Service for the Project and Landlord shall
purchase and install, or have installed, as part of the Base Building Changes
such transformers, switchgear and related circuits and equipment ("PRIMARY
SERVICE FACILITIES") as are necessary to handle such increased Primary
Electrical Service. Tenant shall reimburse Landlord as a Hard Cost as provided
in Section 4 above all incremental increased costs for the Primary Service
Facilities and costs to reimburse PG&E for the extension and installation of the
Primary Electrical Service over the estimated costs to provide secondary
service. Upon installation, such Primary Service Facilities shall become part of
the Building Systems for purposes of the Lease.

      (b) To the extent that any delay in Landlord's delivery of the Premises,
or any floor thereof, occurs due to a delay in the installation of the Primary
Service Facilities due to any reason, including without limitation, any delay in
obtaining or installing such equipment due to any one or more of the events
described in Section 26 - Force Majeure of the Original Lease, or a failure or
defect in the Primary Service Facilities themselves, shall constitute a Tenant
Delay for purposes of the Lease, including, without limitation, calculating the
Partial Rent Commencement Dates for any effected floor of the Premises. However,
and notwithstanding the foregoing, if and to the extent any delay in Landlord's
delivery of the Premises is due to (i) an affirmative rejection by PG&E of its
contractual obligation to install and serve the Project with primary electrical
service, or an unequivocal and formal denial of primary electrical service to
the Project by PG&E, or (ii) any other delay in the installation of the primary
electrical service to the Project by PG&E or an alternative energy provider and
not directly caused by Tenant or its Representatives ("PRIMARY SERVICE DELAY"),
then such a delay shall be considered a delay under Section 26 - Force Majeure
of the Original Lease, but the date set forth in Section 2.2(g) of the
Construction Rider (as amended by Section 10 of this Amendment) at which time
Tenant may elect to terminate the Lease (as provided therein), nevertheless
shall be deferred, day for day, during the period of time that the Primary
Service Delay continues.

      (c) Furthermore, and notwithstanding anything to the contrary in Section
9.3 of the Original Lease, once the Primary Service Facilities and the Primary
Electrical Service has been installed and the applicable Partial Rent
Commencement Dates for each floor have occurred,


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Tenant shall not be entitled to an abatement of rent or to terminate the Lease
as a result of a Service Failure that occurs or arises out of a failure of or
defect in any of the Primary Service Facilities themselves except only if and to
the extent such failure is caused by Landlord's failure to maintain same
pursuant to Section 7.2 of the Original Lease; provided, however, that if the
repair or replacement of any component of the Primary Service Facilities is
delayed due to any one or more of the events described in Section 26 - Force
Majeure of the Original Lease, the date for the commencement of rent abatement
under Section 9.3(a) of the Original Lease shall be deferred during the period
of such delay. The foregoing provisions of this Section 8(c) shall not serve to
waive or supercede the provisions or rights of the parties under Section 9.3 of
the Original Lease pertaining to any Service Failure that occurs for any reason
specified therein, other than if and to the extent such Service Failure is due
to a failure or defect in the Primary Service Facilities themselves or in the
manner of their installation on the Property. Landlord represents to Tenant that
Tenant is a specifically named third-party beneficiary of certain warranties
made by Webcor Builders, as general contractor for the Base Building, under
Section 17.2 of the construction contract for the Base Building. A true and
complete copy of said Section 17.2 is attached hereto as Attachment D. Landlord
agrees not to modify to Tenant's detriment any of said warranties for which
Tenant is a specified third-party beneficiary without Tenant's prior written
consent.

      9. Deferral of Tenant Improvements. Landlord and Tenant acknowledge that
prior to the Effective Date, Tenant prepared and Landlord approved (i) the Space
Plan, and (ii) the Final Working Drawings and Specifications for the Tenant
Improvements, intended for the Premises depicted in Exhibit A to the Original
Lease. Thereafter, Landlord entered into a contract with CIC to construct the
Tenant Improvements and certain components thereof were ordered by CIC and
construction began. On April 10, 2001, Tenant requested Landlord to stop
construction of the Tenant Improvements and to defer their continuation, other
than to complete plan checking by the City of Foster City, but not to pull the
building permit therefor. Landlord agrees to defer the construction of the
Tenant Improvements (the "TI DEFERRAL") for a period of six (6) months from the
Effective Date of this Amendment (the "TI DEFERRAL PERIOD"). As consideration
for the TI Deferral, Tenant agrees to pay to Landlord as and when provided in
Section 4 above, all reasonable costs incurred and to be incurred by Landlord in
connection with (i) the Tenant Improvements undertaken as of the Effective Date,
(ii) the TI Deferral itself, including without limitation, costs for items
ordered, restocking charges for returned items, storage costs, contract
termination/suspension/de-mobilization charges for CIC and its subcontractors,
and (iii) all reasonable costs for any Redesign Efforts for the Tenant
Improvements (collectively, the "TI SHUTDOWN COSTS"). The TI Deferral shall not
apply to or effect any portion of the Base Building Work, including, without
limitation, any Base Building Changes approved by Tenant and Landlord pursuant
to this Amendment, or any other obligation of Landlord or Tenant under the
Lease. Subject to the foregoing, and provided that no default by Tenant has
occurred or occurs in connection with the Lease or no other condition or event
occurs which with the passage of time or giving of notice or both, would
constitute a default under the Lease, Landlord hereby waives any right it may
have to declare a default solely due to the TI Deferral undertaken by Landlord
at Tenant's request, but only for the TI Deferral Period. The foregoing waiver
by Landlord shall not constitute a waiver or release (i) of any Claim or right
in favor of Landlord with respect to any other default or matter by Tenant, or
(ii) of any of Landlord's rights to obtain damages or other remedies against
Tenant


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pertaining to the TI Deferral Period due to (x) such other default, or (y) any
default which occurs after the TI Deferral Period, or (iii) of any claim of
Tenant Delays applicable to the TI Deferral Period due to the TI Deferral.
Nothing in this Amendment shall be construed as an acknowledgement or admission
by Tenant that the TI Deferral constitutes a default or breach under the Lease,
or a failure by Tenant to fully observe, perform and discharge its obligations
under the Lease, and Tenant hereby disputes any such construction of the Lease.
Landlord and Tenant reserve until after the TI deferral Period all rights to
assert their differing interpretations of what duties are imposed by the Lease
concerning the construction of Tenant Improvements. Tenant agrees to pay to
Landlord all reasonable costs in connection with the re-commencement of the
construction of the Tenant Improvements including, without limitation, all costs
of any Redesign Efforts requested or necessary therefor, any increases in unit
costs and labor rates for the Tenant Improvements and re-mobilization charges,
but otherwise in the manner and amount provided under the Original Lease.
Landlord's obligation under the Lease to construct the Tenant Improvements and
to pay the Tenant Improvement Allowance is expressly conditioned upon Tenant's
delivery to Landlord of (i) timely payment for all the TI Shutdown Costs, (ii)
an unconditional written request to immediately re-commence the Tenant
Improvements for the Premises (or a request to initiate further Redesign Efforts
in connection with the Tenant Improvements which results in a revised Space Plan
and revised Final Working Drawings and Specifications for the Premises which are
approved by Landlord and Tenant pursuant to the Construction Rider under the
Original Lease and the reimbursement of Landlord for all costs incurred in
connection with such Redesign Effort in the manner provided in this Amendment)
(in either case, a "GO-AHEAD NOTICE"), and (iii) the 25% deposit for the
Additional Costs for the Tenant Improvements as provided in Section 2.3 of the
Construction Rider of the Original Lease ("TENANT IMPROVEMENT DEPOSIT"). At such
time and so long as the unbilled portion of the estimated costs for the Tenant
Improvements (plus a prudent, reasonable contingency therefor) is equal to or
less than the Tenant Improvement Deposit, invoices for the Additional Costs
shall apply a portion of the Tenant Improvement Deposit as a credit against the
Additional Costs in said invoice, provided that, at all times, the Tenant
Improvement Deposit held by Landlord is equal to the remaining unbilled
estimated Additional Costs (plus a prudent, reasonable contingency therefor)
until such time as the Tenant Improvements have been totally completed and
Tenant has fully paid to Landlord all the Additional Costs. If through the
foregoing process and upon completion of the Tenant Improvements, Tenant ends up
having paid more than the total Additional Costs, Landlord shall refund the
excess to Tenant within ten (10) Business Days of Landlord's receipt of Tenant's
final payment therefor.

      10. Correction of Certain Dates and References. The Scheduled Final Rent
Commencement Date referenced in the Basic Lease Information is hereby extended
to March 1, 2002. The date of October 1, 2002 as first referenced twice in
Section 2.2(g) of the Construction Rider is hereby extended to November 1, 2002.
The date of November 1, 2002 referenced in Section 4 of the Construction Rider
is hereby extended to December 1, 2002. The reference to "Rent Commencement
Date" appearing in the second to last unnumbered paragraph in Section 2.1 of the
Construction Rider shall mean and refer to the "Final Rent Commencement Date."
All references to "Rent Commencement Date" in Subsection 2.2(g) of the
Construction Rider shall mean and refer to the "Partial Rent Commencement Date
for the first floor of the Premises


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delivered to Tenant." The last proviso in Section 2.2(g) is hereby amended and
restated in its entirety to read as follows:

            "; and provided further, if either Landlord or Tenant causes a delay
            so that the Partial Rent Commencement Date for the first floor of
            the Premises delivered to Tenant is delayed past the November 1,
            2002 termination date, then with respect to each, or both, of such
            parties, the November 1, 2002 termination date shall be extended day
            for day for each day that such party causes the Partial Rent
            Commencement Date for the first floor of the Premises delivered to
            Tenant to be delayed beyond such termination date (which extension
            may be applicable to both parties, for different periods of time)."

      11. First Level Space. Tenant acknowledges that at its request, Landlord
deferred seeking the Proposed Reclassification from the City, and that November
1, 2000, the date when Landlord was otherwise to have attempted to achieve the
Proposed Reclassification, has long since passed. Therefore, Landlord and Tenant
agree to release each other and their respective representatives from, and to
waive all Claims against same with respect to, any obligation to pursue the
Proposed Reclassification or to occupy any such space so reclassified. As of the
Effective Date, Landlord and Tenant acknowledge that the Reduction Space equals
17,410 rentable square feet, that the number of parking spaces shall be reduced
by eighty-eight (88), and the number of access cards to be provided by Landlord
free of charge shall be reduced by eighty-eight (88). As of the Effective Date,
Landlord and Tenant hereby agree that the Total Rentable Area in the Premises
shall be 381,050 rentable square feet, and that Tenant's Operating Cost Share is
100% and Tenant's Tax Share is 95.63%. In addition, by virtue of the foregoing,
Tenant will not be leasing the entire rentable area of the Premises, and
Landlord and Tenant shall re-allocate the Project Costs pursuant to the last two
(2) unnumbered paragraphs in Section 3.2(a)(1) of the Original Lease.

      12. Entire Agreement. All attachments, exhibits and addenda attached
hereto are incorporated into this Amendment. This Amendment, together with the
Original Lease, contains the entire agreement of the parties hereto with respect
to the subject matter hereof and may not be changed or terminated orally or by
course of conduct.

      13. Counterparts. This Amendment may be executed in counterparts, each of
which shall be deemed an original as against the party whose signature is
affixed thereto, and together which shall constitute but one and the same
agreement.

      14. Reaffirmation of Lease. Except only as set forth in this Amendment,
the provisions of the Original Lease remain unchanged and in full force and
effect. This Amendment shall be binding upon and inure to the benefit to the
parties and their respective successors and assigns.


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      IN WITNESS WHEREOF, Landlord and Tenant have entered into and executed
this Amendment as of the Effective Date.


TENANT:
INKTOMI CORPORATION,
a Delaware corporation


By:    /s/ Jerry Kennelly
       --------------------------------
Name:  Jerry Kennelly
       --------------------------------
Title: Chief Financial Officer
       --------------------------------

By:
       --------------------------------
Name:
       --------------------------------
Title:
       --------------------------------



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LANDLORD:

PARKSIDE TOWERS CO-TENANCY,
a tenancy in common:

5990 SEPULVEDA ASSOCIATES, L.P.,           GATEWAY PHOENIX ASSOCIATES, L.P.,
a California limited partnership           a California limited partnership

By: Cornerstone Holdings, LLC              By: Cornerstone Holdings, LLC,
    a Delaware limited liability               a Delaware limited liability
    company its general partner                company its general partner

    By: EOP Operating Limited
        Partnership, a Delaware limited    By: EOP Operating Limited
        partnership                            Partnership, a Delaware limited
        Its sole member                        partnership
                                               Its sole member
        By: Equity Office  Properties
            Trust, a Maryland real estate      By: Equity Office  Properties
            investment trust                       Trust, a Maryland real estate
            Its general partner                    investment trust
                                                   Its general partner
            By:   /s/ Peter Adams
                  ---------------
            Name: Peter H. Adams              By:    /s/ Peter Adams
                  --------------                     ---------------
            Its:  Senior Vice President       Name:  Peter H. Adams
                  ---------------------              --------------
                                                Its: Senior Vice President
      (CO-OWNER)                                     ---------------------

                                               (CO-OWNER)


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                                  Attachment A

                              Base Building Changes


ELECTRICAL CHANGES

1.    Add (1) 21KV main service and feeder to PG&E.

2.    Rework existing underground core and shell feeders at new unit
      substations. (Grounding system upgrade released per tenant approval at
      subcontractor cost of $85,812.00)

3.    Install, terminate and test (4) 2250KVA Hitec units.

4.    Provide and install additional unit substations, static transfer
      switches, panelboards and bus risers required for the tenant's computer
      room power and redundant system needs.

5.    Provide additional motor control centers and wiring for redundant
      mechanical system equipment at each tower.

6.    Increase the size of the emergency generator to handle the larger supply
      fans SF-2E and SF-2W.

7.    Revise the penthouse lighting to match the new floor plans.

8.    Revise the 1st floor garage lighting for the added electrical rooms.

9.    Conduit and control wiring for Staefa control system.

10.   Install (2) 4" conduits from the west telephone riser room to Hillsdale
      for future competitive access provider.

11.   Redesign original electrical and telephone rooms on all tenant floors to
      accommodate larger tenant requirements.



HVAC CHANGES

1.    PIPING SYSTEM

A     Chiller and cooling tower upgrade per tenant requirements ( Chillers &
      Cooling Tower released per tenant approval at subcontractor cost of
      $930,576.00).

B     Piping and pump upgrade per new chiller and cooling tower plant.

C     Primary and secondary pumping system (Chilled water & Hot water).

D     Piping control upgrade per Staefa Control.

E     Boiler upgrade: Indoor to outdoor (East Tower only); Two stage to Three
      Stage (Both East & West Tower); relocate boiler to 4th floor of west tower

F     Hot water Risers (2) upgrade (East & West Tower).

G     Chilled water riser (1) add for both East & West Towers.

H     Cooling Tower filtration system (Lakos).

I     Vibration Isolation Upgrade based on upgraded Chiller & Cooling Tower
      Plant.

J     Water treatment upgrade.

K     Pump room air conditioning (8th Floor - East & West Towers).


2.    AIR SYSTEM

A     Supply fan upgrade (Motor HP Change from 100 HP to 125 HP - East Tower &
      75 to 100 HP - West Tower).

B     Cooling Coil Upgrade.


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C     Supply duct riser, duct tap and Fire smoke damper modifications at the
      shaft.

D     VFD add for secondary chilled water pumps, cooling tower upgrade, Fan
      upgrade (100 to 125 & 75 to 100 HP).


3.    CONTROL UPGRADE

A     Change building HVAC control from Siebe to Staefa Control.

B     York talk panel.

C     Harmonic study.


STRUCTURAL CHANGES

1.    Modify structural steel frame to accommodate increased loads on penthouse
      and 4th floor roofs (Modifications released per tenant approval at
      approximate subcontractor cost of $398,000).

2.    Modify metal decking on penthouse roofs to accommodate increased loads.


ARCHITECTURAL CHANGES

1.    SITE

A     Added 10,000 gallon under ground diesel fuel storage tank adjacent to
      Loading Area.

B     Added PG&E pull vault at Shell Blvd., north access drive median.

C     Deleted PG&E switch adjacent to northwest corner of west tower.

D     Future grease trap for tenant food service functions.

2.    LEVEL 1

A     Revised main electrical service rooms, including 21KV service
      requirements.

B     Added rooms for main service, including substation and switchboard
      equipment.

C     Reconfigured loading area and added space to accommodate standby power
      functions.

D     Eliminated 40 parking spaces and reconfigured drive aisle near loading
      dock.

3.    Level 2

A     Added standby power electrical room west of loading bay.

B     Added mechanical plenum, fan room, and heat rejection equipment room east
      of loading bay.

C     Coordinated diesel exhaust, discharged to exterior face of building.

D     Added two electrical/telecom rooms to accommodate increased riser
      requirements.

4.    Level 3

A     Added two electrical/telecom rooms to accommodate increased riser
      requirements.

5.    Level 4

A     Added west tower boiler room, adjacent to Stair No. 5.

B     Revised electrical/telecom room configurations, including revised riser
      requirements.

C     Coordinated electrical/telecom in-floor distribution.

6.    Level 5

A     Added roof screen elements to accommodate tenant equipment.

B     Revised electrical/telecom room configurations, including revised riser
      requirements.


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7.    Level 6 and 7

A     Revised electrical/telecom room configurations, including revised riser
      requirements.

8.    Level 8

A     Revised electrical/telecom room configurations, including revised riser
      requirements.

B     Added Mechanical Pump Rooms adjacent to north mechanical shafts.

9.    Penthouse / Roof Level

A     Redesigned East and West penthouses to accommodate new mechanical and
      electrical equipment.

B     Revised Penthouse roof to reflect plan changes.


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                                  Attachment B

                         Revised Construction Schedules



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                                  Attachment C

                                Revised Premises



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<PAGE>
                                  Attachment D

  Warranty Section 17.2 of Webcor Builders Construction Contract for the Base
                                    Building


17.2 Contractor warrants and guarantees that all materials furnished under the
Contract Documents shall be new and of a quality equal to or better than what
would be acceptable industry standard for comparable projects, unless otherwise
specified in the Plans and Specifications, and that the Work will be of good
quality, free from fault or defect, and in conformance with the Contract
Documents. In furtherance of that guaranty, Contractor agrees to indemnify,
protect, defend and hold harmless Owner against all Claims arising from or
relating to any defect in workmanship or material in the Work or any
non-conformance of the Work with the requirements of the Contract Documents or
applicable laws ("Warranty Claims"). Upon receipt of written notice from Owner,
Contractor shall, at its own expense and under the terms and conditions of the
Contract Documents, promptly and diligently replace any defective or
non-conforming portions of the Work. Contractor shall also bear all costs and
expenses, replace any materials and perform any labor required to correct or
repair any portion of the Project or Property damaged or destroyed in repairing
or correcting any defective or non-conforming Work. This guaranty requires
Contractor to correct the substandard condition and not merely to pay money
damages for breach of the guaranty. If Contractor fails, after written notice
from Owner, to promptly and diligently comply with its obligations, as required
herein, Owner may perform those obligations, at Contractor's expense, and
Contractor shall reimburse Owner promptly upon demand for all costs or expenses
incurred by Owner in connection with fulfilling Contractor's guaranty, including
without limitation, interest on the amounts expended at the Interest Rate and
reasonable attorneys' fees. The provisions of this Section are in addition and
cumulative to other rights and remedies available to the parties under this
Agreement, at law or in equity, and do not in any manner limit such rights and
remedies. The obligations of Contractor under this Section 17.2 shall survive
completion of the Project and termination of this Agreement for a period of one
(1) year following the date of Total Completion of the Project, whether by
Contractor, or in the case of termination of this Agreement by Owner pursuant to
Section 12, by Owner or another party, and shall apply with respect to all
Warranty Claims of which Contractor is aware or is given written notice prior to
the expiration of that time period. During the eleventh (11th) month following
Substantial Completion of the Project, Contractor will conduct an inspection of
all systems, components and all other portions of the Work covered by warranties
for the purpose of identifying any Warranty Claims, all of which shall be
detailed on a punch list and shall be promptly corrected by Contractor. This
inspection will be completed with Owner's designated representative. It is
intended that the purpose of this inspection will be to identify any items that
need attention/correction prior to the expiration of the warranty period.
Contractor acknowledges that the Tenant is an intended third-party beneficiary
of all the warranties described in this Section 17.2.


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