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                                                                   EXHIBIT 10.44



                                 AMENDMENT NO. 1

                                       TO

                    SECOND AMENDED AND RESTATED AGREEMENT FOR


                       EPI OPERATIONAL MANAGEMENT SERVICES


         THIS AMENDMENT NO. 1 (this "Amendment"), dated as of September 15, 2000
(the "Effective Date"), is made and entered into by and between UBS AG, a
corporation organized under the laws of Switzerland ("UBS AG"), and Perot
Systems Corporation, a Delaware corporation ("PSC"). As used in this Amendment,
"party" means either UBS AG or PSC, as appropriate, and "parties" means UBS AG
and PSC, collectively.


                                    RECITALS


         A. Swiss Bank Corporation (a predecessor of UBS AG) and PSC entered
into a Second Amended and Restated Master Agreement For EPI Operational
Management Services, dated as of June 28, 1998 (the "SBC Warburg EPI
Agreement").

         B. The parties desire to amend the SBC Warburg EPI Agreement as set
forth below.

         C. Concurrently with the execution of this Amendment, the parties are
entering into Amendment No. 1 to Amended and Restated Master Operating
Agreement.

         In consideration of the foregoing and other good and valuable
consideration, the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

                                   AMENDMENTS

1.       DEFINITIONS.

         1.1. A definition of "Additional MDS Services" is hereby added to
Section 3 of the SBC Warburg EPI Agreement to read in its entirety as follows:


                  "Additional MDS Services" means with respect to PSC Market
                  Data Services Agreements (i) acquisition and authorization of
                  Market Data Services from MDS Providers, (ii) business
                  management, financial reporting, contract administration and
                  management related to the MDS Providers, and (iii)
                  authorization, validation and payment of invoices from MDS
                  Providers, all for internal users within the SBC Warburg
                  Division only (i.e. not external customers of the SBC Warburg
                  Division or other third parties). For clarification,
                  "Additional MDS Services" shall apply only to PSC Market Data
                  Services Agreements and shall not apply to any SBC Warburg
                  Market Data Services Agreements that are not assigned or
                  transferred to PSC.





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         1.2. A definition of "Market Data Services" is hereby added to Section
3 of the SBC Warburg EPI Agreement to read in its entirety as follows:

                  "Market Data Services" means the provision of financial and
                  market news and information through electronic media.

         1.3. A definition of "MDS Provider" is hereby added to Section 3 of the
SBC Warburg EPI Agreement to read in its entirety as follows:

                  "MDS Provider" means a third party provider of Market Data
                  Services.

         1.4. The term "Moves and Restacks" at Section 3(c) of the SBC Warburg
EPI Agreement is deleted in its entirety and replaced with the following:

                  "Moves and Restacks" means the process of relocating the staff
                  of the SBC Warburg division and its contractors within and
                  among the offices of the SBC Warburg Division, including
                  moving Equipment.

         1.5. A definition of "PSC Market Data Services Agreements" is hereby
added to Section 3 of the SBC Warburg EPI Agreement to read in its entirety as
follows:

                  "PSC Market Data Services Agreements" mean: (i) the Initial
                  Assigned Market Data Services Agreements; (ii) any other SBC
                  Warburg Market Data Services Agreements that are assigned or
                  transferred to PSC pursuant to the terms of this Amendment;
                  and (iii) any agreements approved by the SBC Warburg Division
                  in accordance with Section 3.7 of this Amendment that are
                  entered into between PSC and an MDS Provider under which PSC
                  contracts for Market Data Services on behalf of one or more
                  SBC Warburg Division Members.

         1.6. A definition of "SBC Warburg Market Data Services Agreement" is
hereby added to Section 3 of the SBC Warburg EPI Agreement to read in its
entirety as follows:

                  "SBC Warburg Market Data Services Agreement" means any
                  existing or future agreement between an SBC Warburg Division
                  Member and an MDS Provider under which one or more SBC Warburg
                  Division Members receives Market Data Services.

         1.7. The term "Services" at Section 3(i) of the SBC Warburg EPI
Agreement is deleted in its entirety and replaced with the following:

                  "Services" mean, collectively, the services required for (i)
                  the Operational Management of the EPI of each SBC Warburg
                  Division Member, (ii) the Additional MDS Services, and (iii)
                  the transition of the Network Services and the Additional MDS
                  Services in accordance with this Amendment, including the
                  services described in the Amended and Restated Schedule A
                  hereto.

         1.8. A definition of "Transition Date" is hereby added to Section 3 of
the SBC Warburg EPI Agreement to read in its entirety as follows:





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                  "Transition Date" means January 2, 2001 or such other date
                  agreed by the parties in writing, assuming that as of such
                  date each of the following conditions shall have been
                  satisfied: (i) those PSC Network Personnel electing to become
                  employed or retained by the Designated UBS Entity (as
                  hereinafter defined) have transferred to the Designated UBS
                  Entity; and (ii) a sufficient number of SBC Warburg Market
                  Data Services Agreements have been assigned to PSC, in whole
                  or in part, such that the Threshold Amount (as hereinafter
                  defined) is, in the reasonable determination of PSC, expected
                  to be met.

2.       NETWORK SERVICES.

         2.1. REMOVAL OF NETWORK SERVICES. From and after the Transition Date,
Network Services (as defined in Amendment No. 1 to the Amended and Restated
Master Operating Agreement) shall no longer be included as part of the
"Services" or "Scope of Services" that are the subject of the SBC Warburg EPI
Agreement, except inasmuch as services related to the Network (as defined in
Amendment No. 1 to the Amended and Restated Master Operating Agreement) and
Network Services are necessary for PSC to fulfill its obligation to complete the
transition of Network Services pursuant to this Amendment (which may include,
among other things, the continued provision of certain Network Services pursuant
to Section 2.2(g) below). Accordingly, and without limiting the generality of
the foregoing, the SBC Warburg EPI Agreement is hereby amended as follows:

         (a) Schedule A of the SBC Warburg EPI Agreement is deleted in its
entirety and replaced with the Amended and Restated Schedule A, attached hereto
as Exhibit A.

         (b) Section 4 of Schedule F of the SBC Warburg EPI Agreement shall not
apply to any Network Services (but shall continue to apply to other Services).
The cross-reference to "Section 3(f)" in line two (2) of Section 4 of Schedule F
of the SBC Warburg EPI Agreement is hereby corrected to reference "Section
3(g)."

Except as otherwise provided herein, this Amendment shall not affect any rights
or obligations of the parties under the SBC Warburg EPI Agreement in connection
with any Network Services provided by Perot Systems prior to the completion of
the transition of Network Services.

    2.2. TRANSITION OF NETWORK SERVICES.

         (a) Network Transition. During the period beginning on the Effective
Date (or such earlier date as the parties may mutually agree upon), the parties
shall plan, prepare for and conduct the transition of Network Services to an SBC
Entity, as designated by UBS AG (the "Designated UBS Entity"), in accordance
with the Network Transition Plan (the "Network Transition"). For purposes of
this Amendment, "Designated UBS Entity" shall mean UBS AG until such time as UBS
AG designates another Designated UBS Entity in a written notice to PSC. PSC's
responsibilities with respect to the Network Transition shall include:

               (i) Developing, together with the Designated UBS Entity, a plan
for the orderly transition of performance of Network Services from PSC to the
Designated UBS Entity;



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               (ii) Maintaining, in accordance with the SBC Warburg EPI
Agreement, the Network Services provided by the operations being transitioned;

               (iii) Providing all information in PSC's control that is
reasonably requested by the Designated UBS Entity relating to the Network and
PSC's provision of Network Services;

               (iv) Providing reasonable training requested by the Designated
UBS Entity relating to the performance of the Network Services;

               (v) Providing the Designated UBS Entity (and its contractors,
consultants and agents) access to and use of the Equipment, Systems, personnel,
data, documentation and other resources and material that PSC uses to provide
Network Services, to the extent such access and use will not have a material
negative impact on PSC's ability to (i) provide the Services in accordance with
the SBC Warburg EPI Agreement or (ii) meet the PSC Costs Budget; and

               (vi) Otherwise providing the ongoing assistance referenced in
subsection (g) of this Section 2.2 in order to allow the Network Services to
continue and to facilitate the orderly transfer of responsibility for
performance of the Network Services, including performing such transition tasks
as are necessary to enable the Designated UBS Entity to provide Network Services
for itself following the Network Transition.

     (b) Network Transition - UBS AG Responsibilities. UBS AG's responsibilities
with respect to the Network Transition shall include:

               (i) Developing, together with PSC, a plan for the orderly
transition of performance of Network Services from PSC to the Designated UBS
Entity; and

               (ii) Participating in the Network Transition in a manner that
does not have a material negative impact on PSC's ability to (i) provide the
Services in accordance with the SBC Warburg EPI Agreement or (ii) meet the PSC
Costs Budget.

     (c) Network Transition Plan. The Network Transition shall be conducted in
accordance with a written plan developed by UBS AG and PSC which shall, among
other things: (1) provide for Network Services to be fully transitioned by
January 2, 2001; (2) describe the schedule and respective roles and
responsibilities of the parties in undertaking the Network Transition; and (3)
provide such other information, planning and tasks as are necessary to ensure
that the Network Transition takes place on schedule and without disruption to
the business operations of the SBC Warburg Division or PSC's ability to provide
the Services in accordance with the SBC Warburg EPI Agreement (the "Network
Transition Plan"). The parties shall use all commercially reasonable efforts to
finalize the Network Transition Plan no later than sixty (60) days following the
Effective Date. PSC and UBS AG each will use all commercially reasonable efforts
to perform the tasks required of it by the Network Transition Plan.

     (d) Personnel.





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               (i) The Designated UBS Entity shall offer full-time employment to
all PSC employees listed as "Associates" in Exhibit C ("PSC Network Employees"),
with such employment to commence in accordance with the Network Transition Plan.
In addition, the Designated UBS Entity shall offer to retain as independent
contractors the individuals listed as "Contractors" in Exhibit C ("PSC Network
Contract Personnel"), with such engagements to commence in accordance with the
Network Transition Plan. PSC Network Employees and PSC Network Contract
Personnel are referred to herein collectively as "PSC Network Personnel."

               (ii) The Rules of Engagement, attached hereto as Exhibit B, set
forth the period of time during which offers of employment will be made and
accepted and the procedures to be followed for making and accepting such offers,
as well as the procedures to be followed for transferring PSC Network Contract
Personnel.

               (iii) PSC shall cooperate in facilitating the hiring process to
the extent reasonably practicable, but shall in no event require PSC Network
Employees to terminate their employment relationship with PSC. In the case of
PSC Network Contract Personnel, PSC shall use all commercially reasonable
efforts to obtain any required consents and otherwise cooperate in the transfer
or assignment to the Designated UBS Entity of the contractor agreement(s), but
shall in no event require PSC Network Contract Personnel to terminate their
relationship with PSC as independent contractors. Among other things, PSC shall
provide: (1) information on salary and benefits structures for the PSC Network
Employees, or, in the case of PSC Network Contract Personnel, the terms and
conditions of the contractor agreement(s); (2) a current organizational chart by
individual PSC Network Personnel; (3) information on any personnel resource
requirements for Operational Management of the Network that are not being
satisfied by PSC Network Personnel; and (4) any other information reasonably
requested by the Designated UBS Entity. Subject to Subparagraph (iv) below, no
member of the PSC Group shall offer any PSC Network Personnel other positions
within the PSC Group pending completion of the offer and acceptance process.

               (iv) In accordance with the Rules of Engagement section of the
Network Transition Plan, PSC may offer positions within the PSC Group to the PSC
Network Employees designated as "Potential Candidates" in Exhibit C.

               (v) In the event that on December 22, 2000 (A) the Designated UBS
Entity has in place valid written commitments from seventy-five percent (75%) of
the PSC Network Personnel to transfer to the Designated UBS Entity (the
"Transfer Commitment Goal"), as reported by UBS AG in a format conforming to
Exhibit C, and (B) the parties have in place written consents from MDS Providers
consenting to the assignment, in whole or in part, of a sufficient number of SBC
Warburg Market Data Services Agreements such that the Threshold Amount for
Additional MDS Services is, in the reasonable determination of Perot Systems,
expected to be met (the "MDS Assignment Consent Goal"), UBS AG shall pay to PSC
a cash bonus in the amount of Three Million Dollars ($3,000,000) on or before
December 25, 2000. PSC shall use all commercially reasonable efforts to assist
UBS AG and the Designated UBS Entity in achieving the Transfer Commitment Goal
and MDS Assignment Consent Goal.

               (vi) Each party shall perform its obligations relating to the
transfer of the PSC Network Personnel such that the transfer of the PSC Network
Personnel shall be in







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compliance with all local laws. UBS AG and PSC each shall be responsible for
ensuring that all required regulatory filings, within its scope of
responsibility for the transfer, are made to facilitate such staff transfer. UBS
AG and PSC shall coordinate such filings to ensure compliance.

               (vii) Neither Section 11.3 of the Amended and Restated Master
Operating Agreement nor Section 4.6 of the Master Agreement shall apply to the
offers of employment described in this Section 2.2(d).

         (e) PSC Software. PSC represents that Exhibit D attached hereto
includes a complete list of the Licensed PSC Programs used by PSC in providing
the Network Services. PSC hereby grants to UBS AG a license to use the Licensed
PSC Programs in accordance with Section 4.3 of the Amended and Restated Master
Operating Agreement as if the Network Transition was a termination of the SBC
Warburg EPI Agreement as contemplated by Section 4.3. The license granted hereby
is assignable by UBS AG to the Designated UBS Entity with notice to PSC.

         (f) Equipment, Service Contracts, Facilities and Third Party Software.
PSC represents to UBS AG that:

               (i) PSC is not using any computer-related or communications
equipment that is owned or leased by a PSC Entity (as defined in Section 1.1(v)
of the Amended and Restated Master Operating Agreement) as part of the Network
or to provide Network Services;

               (ii) no agreements with third parties under which services are
provided by such third parties with respect to the Network, including agreements
with telecommunications carriers for the transport of voice and data traffic and
provision of local service, are in the name of a PSC Entity;

               (iii) PSC is not performing any Network Services at PSC
Facilities; and

               (iv) PSC is not using any licensed or leased PSC System (as
defined in Section 1.1(x) of the Amended and Restated Master Operating
Agreement) as part of the Network or to provide Network Services.

     (g) Ongoing Assistance. PSC shall continue to provide, and UBS AG shall be
obligated to reimburse PSC for, any Network Services that are not fully
transitioned by the Transition Date until the Network Transition is completed.
Such continuing services shall include making any and all PSC Network Personnel
who do not accept offers of employment with the Designated UBS Entity available
to UBS AG to continue performing Network Services until the Designated UBS
Entity notifies PSC that such PSC Network Personnel are no longer needed to
perform the Network Services; provided, however, that PSC shall not be in
violation of this obligation if it is unable to make particular PSC Network
Personnel available to the Designated UBS Entity due to the death, disability or
termination of employment of such PSC Network Personnel. All costs incurred by
PSC in providing this ongoing assistance will be PSC Costs in addition to those
reflected in the 2000 PSC Costs Budget.




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3.       MARKET DATA SERVICES.

         3.1. ADDITIONAL MDS SERVICES. From and after the Transition Date, in
addition to those Services PSC currently provides with respect to Market Data
Services as part of the Scope of Services, PSC shall also be responsible for the
Additional MDS Services in accordance with the terms of the SBC Warburg EPI
Agreement. Accordingly, and without limiting the generality of the foregoing,
Schedule A of the Warburg EPI Agreement is deleted in its entirety and replaced
with the Amended and Restated Schedule A, attached hereto as Exhibit A.

         3.2. TRANSITION OF MARKET DATA SERVICES.

          (a) Transition. During the period beginning on the Effective Date (or
such earlier date as the parties may mutually agree upon), the parties shall
plan, prepare for and conduct the transition of the Additional MDS Services to
PSC in accordance with the MDS Transition Plan (the "MDS Transition").

          (b) MDS Transition Plan. The MDS Transition shall be conducted in
accordance with a written plan developed by UBS AG and PSC which shall, among
other things: (1) provide for assigning the Initial Assigned Market Data
Services Agreements by January 2, 2001 (subject to obtaining required consents
from the applicable MDS Providers); (2) describe the schedule and respective
roles and responsibilities of the parties in undertaking the MDS Transition; and
(3) provide such other information, planning and tasks as are necessary to
ensure that the MDS Transition takes place on schedule and without disruption to
the business operations of the SBC Warburg Division or PSC's ability to provide
the Services in accordance with the SBC Warburg EPI Agreement (the "MDS
Transition Plan"). The parties shall use all commercially reasonable efforts to
finalize the MDS Transition Plan no later than sixty (60) days following the
Effective Date. PSC and UBS AG each will use all commercially reasonable efforts
to perform the tasks required of it by the MDS Transition Plan.

          (c) Personnel.

               (i) A PSC Entity designated by PSC (each, a "Designated PSC
Entity") shall offer full-time employment to the individuals listed in Exhibit E
attached hereto ("SBC Warburg Division MDS Employees"), with such employment to
commence in accordance with the MDS Transition Plan. UBS and PSC agree that a
total of seven (7) personnel are required to satisfy personnel resource
requirements related to the Additional MDS Services. In addition to the SBC
Warburg Division MDS Employees, and in replacement thereof in the event one or
both of such employees does not accept employment with PSC, the parties agree
that a Designated PSC Entity will attempt to hire additional personnel, to a
total of seven (7) personnel, in order to satisfy personnel resource
requirements referenced above related to the Additional MDS Services.

               (ii) UBS AG and the SBC Warburg Division shall cooperate in
facilitating the hiring process to the extent reasonably practicable, but shall
in no event require individuals to terminate their employment relationship with
the SBC Warburg Division. Among other things, UBS and the SBC Warburg Division
shall provide: (1) information on salary and benefits structures for the SBC
Warburg Division MDS Employees; (2) a current organizational




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chart by individual SBC Warburg Division MDS Employees; (3) information on any
personnel resource requirements for managing the provision of Additional MDS
Services that are not being satisfied by the SBC Warburg Division MDS Employees;
and (4) any other information reasonably requested by PSC. No member of the SBC
Group shall offer any SBC Warburg Division MDS Employees other positions within
the SBC Group pending completion of the offer and acceptance process as
referenced in the MDS Transition Plan.

               (iii) Each party shall perform its obligations relating to the
transfer of the SBC Warburg Division MDS Employees such that the transfer of the
SBC Warburg Division MDS Employees shall be in compliance with all local laws.
UBS AG and PSC each shall be responsible for ensuring that all required
regulatory filings, within its scope of responsibility for the transfer, are
made to facilitate such staff transfer. The parties shall coordinate such
filings to ensure compliance.

               (iv) Section 11.3 of the Amended and Restated Master Operating
Agreement shall not apply to the offers of employment described in this Section
3.2(c).

         (d) Market Data Services Agreements. Subject to obtaining required
consents from the applicable MDS Providers, UBS AG shall assign (or cause the
applicable SBC Group members to assign) to PSC a sufficient number of the SBC
Warburg Market Data Services Agreements, in whole or in part, such that the
total amount of PSC Costs that PSC would reasonably expect to charge under the
SBC Warburg EPI Agreement with respect to the Additional MDS Services would be
equal to or greater than $35,200,000 (Thirty Five Million Two Hundred Thousand
U.S. Dollars) per annum (the "Threshold Amount"). The parties will cooperate in
obtaining all required consents from all MDS Providers. The SBC Warburg Market
Data Services Agreements transferred to PSC pursuant to this Section 3.2(d) are
referred to herein collectively as the "Initial Assigned Market Data Services
Agreements."

         (e) Ongoing Assistance. After the Transition Date, UBS AG shall make
available to PSC, free of charge, SBC Warburg Division MDS Employees who do not
accept employment with a Designated PSC Entity to continue performing the
Additional MDS Services until PSC notifies UBS AG that such employees are no
longer needed to perform the Additional MDS Services; provided, however, that
UBS AG shall not be in violation of this obligation if it is unable to make a
particular SBC Warburg Division MDS Employee available to the Designated PSC
Entity due to the death, disability or termination of employment of such
employee.

         3.3. ASSIGNMENT OF ADDITIONAL MARKET DATA SERVICES AGREEMENTS AFTER
TRANSITION.

         (a) During the period beginning on the Transition Date and ending June
30, 2002, the parties will meet quarterly to discuss the assignment, in whole or
in part, of additional SBC Warburg Market Data Services Agreements (i.e. beyond
the Initial Market Data Services Agreements assigned to PSC pursuant to Section
3.2(d) above) to PSC. In the event that PSC has satisfied the factors set forth
in Exhibit F (the "MDS Compliance Requirements") on a consistent basis through
the date of the proposed assignment, UBS AG will assign (or cause the applicable
SBC Group members to assign) to PSC, in whole or in part, any SBC Warburg





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Market Data Services Agreements that PSC desires to assume, subject to obtaining
required consents from the applicable MDS Providers to the assignment of such
SBC Warburg Market Data Services Agreements on terms identical in all material
respects to those in the applicable SBC Warburg Market Data Services Agreement,
or otherwise on terms reasonably acceptable to UBS AG and PSC. UBS AG will use
commercially reasonable efforts, including without limitation the direct
involvement of the UBS Relationship Manager (as defined in Section 6.1 of the
Amended and Restated Master Operating Agreement) and the UBS Operational Manager
(as defined in Section 6.2 of the Amended and Restated Master Operating
Agreement) with the applicable MDS Providers, to obtain such consents. PSC will
cooperate with UBS in obtaining required consents from MDS Providers.

         (b) Beginning July 1, 2002, PSC may from time to time request that UBS
AG assign, in whole or in part, additional SBC Warburg Market Data Services
Agreements (i.e. beyond the SBC Warburg Market Data Services Agreements assigned
to PSC pursuant to Section 3.2(d) above and Paragraph (a) above) to PSC. In the
event that PSC has satisfied the MDS Compliance Requirements set forth in
Exhibit F on a consistent basis through the date of the proposed assignment, UBS
AG will assign (or cause the applicable SBC Group members to assign) to PSC, in
whole or in part, any SBC Warburg Market Data Services Agreements that PSC
desires to assume, subject to obtaining required consents from the applicable
MDS Providers to the assignment of such SBC Warburg Market Data Services
Agreements on terms identical in all material respects to those in the
applicable SBC Warburg Market Data Services Agreement, or otherwise on terms
reasonably acceptable to UBS AG and PSC. UBS AG will use commercially reasonable
efforts, including without limitation the direct involvement of the UBS
Relationship Manager (as defined in Section 6.1 of the Amended and Restated
Master Operating Agreement) and the UBS Operational Manager (as defined in
Section 6.2 of the Amended and Restated Master Operating Agreement) with the
applicable MDS Providers, to obtain such consents. PSC will cooperate with UBS
in obtaining required consents from MDS Providers.

         (c) From and after the Transition Date, in the event that UBS AG
desires to enter into a new agreement for the provision of Market Data Services
for the benefit of the SBC Warburg Division, PSC will have the right to enter
into such agreement in PSC's name, provided that (A) PSC has satisfied the MDS
Compliance Requirements set forth in Exhibit F on a consistent basis through the
date the new agreement is to be executed, and (B) PSC complies with the
provisions of Sections 3.7 and 3.8 below in negotiating and entering into such
agreement.

         (d) The obligations of UBS AG to assign (or cause the applicable SBC
Group member to assign) SBC Warburg Market Data Services Agreements to PSC, and
to permit PSC to enter into new agreements for the provision of Market Data
Services for the benefit of SBC Group members in PSC's name, are limited to
those obligations set forth in Section 3.2 above and this Section 3.3.

    3.4. MARKET DATA SERVICES SOFTWARE. So long as PSC's ability to manage the
Additional MDS Services is not adversely impacted either operationally or as it
relates to PSC's ability to satisfy the MDS Compliance Requirements, UBS AG or
one or more SBC Warburg Division Members designated by UBS AG shall be named as
the licensee of any software



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provided by MDS Providers under any agreements for Market Data Services entered
into between PSC and an MDS Provider (but, unless negotiated by UBS AG, not
including the Initial Assigned Market Data Services Agreements or other SBC
Warburg Market Data Services Agreements that are assigned or transferred to
PSC).

     3.5. MANAGEMENT OF MARKET DATA SERVICES AGREEMENTS. The SBC Warburg
Division shall be the ultimate recipient of the products and services provided
under all PSC Market Data Services Agreements. Accordingly, all PSC Market Data
Services Agreements shall be managed by PSC for the benefit of UBS AG and the
SBC Warburg Division. All costs incurred under such agreements (but not
including any costs for which any member of the SBC Group is entitled to be
indemnified under Section 3.9(a) below) will be PSC Costs.

     3.6. CHANGES TO PSC MARKET DATA SERVICES AGREEMENTS. As part of providing
the Additional MDS Services, PSC shall negotiate and use all commercially
reasonable efforts to cause to be implemented in a timely manner any changes
requested or approved by UBS AG to any PSC Market Data Services Agreement,
including changes to products, pricing and other terms and conditions. The
negotiation and implementation of any such changes shall be a collaborative
effort by PSC and UBS AG. UBS AG shall have the right to participate in such
negotiations. No changes (including without limitation the exercise by PSC of
renewal options to extend the contract term) shall be made to any PSC Market
Data Services Agreement without the prior written approval of UBS AG (which
approval may be granted or withheld in its sole discretion).

     3.7. NEW PSC MARKET DATA SERVICES AGREEMENTS. As part of providing the
Additional MDS Services, PSC shall, at the request, or upon the approval, of UBS
AG, negotiate and use all commercially reasonable efforts to enter into in a
timely manner new PSC Market Data Services Agreements with suppliers approved by
UBS AG. The negotiation of any new PSC Market Data Services Agreement shall be a
collaborative effort by PSC and UBS AG. UBS AG shall have the right to
participate in such negotiations. No new PSC Market Data Services Agreements
shall be entered into without the prior written approval of UBS AG (which
approval may be granted or withheld in its sole discretion).

     3.8. ASSIGNMENTS BACK TO SBC WARBURG DIVISION. Notwithstanding anything
herein to the contrary, all agreements for Market Data Services entered into
between PSC and an MDS Provider (but, unless negotiated by UBS AG, not including
the Initial Assigned Market Data Services Agreements or other SBC Warburg Market
Data Services Agreements that are assigned or transferred to PSC) shall
expressly permit the assignment of such agreements to UBS AG (or any SBC Warburg
Division Member designated by UBS AG) upon the expiration or termination of the
Warburg EPI Agreement with respect to the Additional MDS Services. UBS AG shall
not be required to assign, in whole or in part, any SBC Warburg Market Data
Services Agreement to PSC unless and until the MDS Provider agrees to permit the
assignment of such agreement back to UBS AG (or any SBC Warburg Division Member
designated by UBS AG) upon the expiration or termination of the Warburg EPI
Agreement with respect to Additional MDS Services. At UBS AG's request upon the
expiration or termination of the SBC Warburg EPI Agreement with respect to the
Additional MDS Services, PSC shall promptly assign all PSC Market Data Services
Agreements to UBS AG (or any SBC Warburg Division Member designated by UBS AG),
subject to obtaining the consent of the MDS Providers with respect to





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those SBC Warburg Market Data Services Agreements assigned to PSC for which UBS
AG did not negotiate the right to such assignment back to UBS AG.

     3.9. INDEMNITIES.

          (a) By PSC. PSC agrees to indemnify, defend and hold harmless the
members of the SBC Group from any and all claims, actions, damages, losses,
liabilities, costs and expenses, including reasonable attorneys' fees and
expenses, arising out of any of the following: (i) any failure of PSC to observe
or perform any duties or obligations to be observed or performed by PSC under
any PSC Market Data Services Agreement, provided that with respect to any SBC
Warburg Market Data Services Agreement assigned to PSC by an SBC Warburg
Division Member, this indemnity shall apply only with respect to such failures
by PSC (A) occurring on or after the effective date of assignment of such SBC
Warburg Market Data Services Agreement, and (B) relating to those portions of
the SBC Warburg Market Data Services Agreement assigned to PSC; (ii) any failure
by PSC to obtain UBS AG's approval as required under Section 3.6 above prior to
making any change to a PSC Market Data Services Agreement; and (iii) any failure
by PSC to obtain UBS AG's approval as required under Section 3.7 above prior to
entering into a new PSC Market Data Services Agreement.

          (b) By UBS AG. UBS AG agrees to indemnify, defend and hold harmless
the members of the PSC Group from any and all claims, actions, damages, losses,
liabilities, costs and expenses, including reasonable attorneys' fees and
expenses, arising out of any failure of the SBC Warburg Division to observe or
perform any duties or obligations to be observed or performed by the SBC Warburg
Division (i) prior to the effective date of assignment under any SBC Warburg
Market Data Services Agreement assigned to PSC; and (ii) after the effective
date of the assignment of the SBC Warburg Market Data Services Agreement to PSC
relating to those portions of the agreement not assigned to PSC.

          (c) Indemnification Procedures. The indemnification procedures set
forth in Section 10.5 of the Amended and Restated Master Operating Agreement
shall apply to any third party claim that is subject to the indemnities set
forth in this Section 3.9.

4.       FINANCIAL.

          4.1. TRANSITION COSTS. UBS AG shall bear all reasonable, documented
costs incurred by PSC that are directly associated with the transition of
Network Services and Market Data Services in accordance with this Amendment,
including the preparation and execution of the Network Transition Plan and MDS
Transition Plan, the transfer of PSC Network Personnel and SBC Warburg Division
MDS Personnel, the assignment of the Initial Market Data Services Agreements and
PSC legal costs. All costs incurred by PSC in providing this ongoing assistance
will be PSC Costs in addition to those reflected in the 2000 PSC Costs Budget.

          4.2. TRANSFER COMMITMENT GOAL BONUS. As provided in Section 2.2(d)(v)
above, in the event that the Transfer Commitment Goal and MDS Assignment Consent
Goal have been attained and are in place on December 22, 2000, UBS AG shall pay
to PSC a cash bonus in the amount of Three Million Dollars ($3,000,000) on or
before December 25, 2000.



                                     - 11 -
<PAGE>   12

     4.3. MARKET DATA SERVICES. Costs incurred by PSC with respect to the
Additional MDS Services shall be treated as PSC Costs and determined in the same
manner as other PSC Costs. The 2000 PSC Costs Budget shall be adjusted
accordingly for such costs.

     4.4. ANNUAL PROFIT AMOUNT. There shall be no change in the Annual Profit
Amount under Schedule F to the SBC Warburg EPI Agreement as a result of the
removal of Network Services or the addition of the Additional MDS Services.

     4.5. DISCOUNT ON OTHER SERVICES. There shall be a fifty percent (50%)
reduction of the profit otherwise chargeable on any services performed for the
SBC Warburg Division by PSC (or any wholly-owned subsidiary) outside of the SBC
Warburg EPI Agreement. This discount shall apply until the SBC Warburg Division
has received an aggregate discount of Three Million Dollars ($3,000,000) over
the remaining term of the SBC Warburg EPI Agreement. This discount shall not
apply to:

          (a) "Additional Services" as defined in the June 16, 2000 letter
between UBS AG and PSC which are currently committed under Project Agreements;
or

          (b) services performed directly by HPS Perot for the SBC Warburg
Division; provided, however, that it is understood and agreed that the use of
subcontractors (including HPS Perot) by PSC will not affect the applicability of
the discount.

     4.6. ADJUSTMENTS TO BUDGET. The parties acknowledge that PSC's cost budget
for the performance of services under the EPI will require adjustment for the
current year and 2001 as a result of the transaction provided for herein.

5.       PERFORMANCE METRICS.

     5.1. PENALTY POOL. The term "Penalty Pool" at Section 1(b) of Schedule G of
the SBC Warburg EPI Agreement is deleted in its entirety and replaced with the
following:

          "Penalty Pool" is, with respect to any Budget Period during the term
          of this EPI Agreement, an amount equal to thirteen percent (13%) of
          the Annual Profit Amount.

     5.2. REWARD POOL. The term "Reward Pool" at Section 1(d) of Schedule G of
the SBC Warburg EPI Agreement is deleted in its entirety and replaced with the
following:

          "Reward Pool" is, with respect to any Budget Period during the term of
          this EPI Agreement, an amount equal to thirteen percent (13%) of the
          Annual Profit Amount.

6.       TERMINATION OF AMENDMENT.

         Prior to the Transition Date, (i) UBS AG shall have the right to
         terminate this Amendment, in its sole discretion, if the Transfer
         Commitment Goal is not met on December 22, 2000, and (ii) PSC shall
         have the right to terminate this Amendment, in its sole discretion, if
         the MDS Assignment Consent Goal is not met on December 22, 2000. If
         this Amendment is terminated pursuant to this Section 6, neither party
         shall have any





                                     - 12 -
<PAGE>   13


          further rights or obligations under this Amendment and the amendments
          set forth herein to the SBC Warburg EPI Agreement shall cease to be
          effective.

7.       MISCELLANEOUS.

     7.1. Any capitalized terms not defined herein shall have the meaning given
them in the SBC Warburg EPI Agreement.

     7.2. The section headings used in this Amendment are for reference and
convenience only and shall not enter into the interpretation of this Amendment.

     7.3. The terms and conditions set forth in this Amendment shall be deemed a
part of the SBC Warburg EPI Agreement for all purposes. In the event of a
conflict or inconsistency between the terms and conditions set forth in this
Amendment and those set forth in the SBC Warburg EPI Agreement, the terms and
conditions of this Amendment shall prevail.

     7.4. Except as provided in this Amendment, the SBC Warburg EPI Agreement
shall remain unchanged and in full force and effect.

     7.5. This Amendment may be executed in several counterparts, all of which
taken together constitute one single agreement between the parties hereto.

         IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
signed and sealed by their duly authorized representatives all as of the day and
year first above written.


UBS AG                                    PEROT SYSTEMS CORPORATION



By:  /s/ Patrick O'Donnell                By:  /s/ James A. Champy
   --------------------------------          -----------------------------
Title:  Managing Director                 Title:  Vice President

By:  /s/ Robert B. Mills
   --------------------------------
Title:  Managing Director and CFO



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