EXHIBIT 10.30

                             FIRST ADDENDUM TO LEASE
                                 BY AND BETWEEN
                THE JOSEPH AND EDA PELL REVOCABLE TRUST, LANDLORD
                                       AND
                  FAIR, ISAAC AND COMPANY, INCORPORATED, TENANT
                               DATED JULY 10, 1993

1.   TENANT IMPROVEMENTS

     A.    Working Drawings and  Specifications  ("Bid  Package"):  Tenant shall
           authorize  Richard  Pollack and Associates or any other  architect or
           architectural  firm of  Tenant's  choice  ("Architect")  to prepare a
           space plan,  construction  drawings and design specifications for the
           Premises.  Tenant may direct  Architect  to utilize  the  services of
           consultants ("Consultants") to provide engineered drawings and design
           specifications for the mechanical, electrical and plumbing systems in
           the  Premises,  including,  but not  limited to any air  conditioning
           system,  duct  work,  heating  and  electric  facilities.  (All  such
           architectural and engineering  drawings and specifications are herein
           referred to collectively as the "Bid Package").  In putting  together
           the Bid Package,  Architect  and  Consultants  shall exert their best
           efforts to reuse all  existing  improvements  in the  Premises  where
           possible  and  in  conformance  with  Tenant's  requirements  in  the
           Premises.  Tenant  shall  not be  required  to reuse  existing  light
           fixtures  in the  Premises,  but rather  shall  specify its own light
           fixtures.  Landlord shall provide the Architect and Consultants  with
           the base building capacity for (1) electrical power, (2) HVAC and (3)
           floor loading (live and dead load  capacities and design criteria for
           the  Premises).  The Bid Package shall be submitted to Tenant for its
           review and  written  approval  which shall be  evidenced  by Tenant's
           signing the Bid Package.  The Bid Package  shall also be submitted to
           Landlord  for  Landlord's  approval  which shall also be evidenced by
           Landlord's signing the Bid Package.  Landlord's approval shall not be
           unreasonably  withheld.  It is the  understanding of the parties that
           Tenant  intends to provide its  employees  with high  quality  office
           space which meets the current needs of the workforce and enhances the
           work  performance of the employees and the company,  while  remaining
           flexible  enough to accommodate  the growth and changing needs of the
           Tenant.  In other words, the Tenant may not always be looking for the
           most economical  solution or method of  construction,  but rather one
           which  provides  Tenant with the highest  ability to perform its work
           while maintaining flexibility for future needs.

           All architectural design,  engineering,  and consulting fees shall be
           included in the Tenant  Improvement  Allowance.  See Addendum  1[1.C.
           Tenant  may  require  that  certain  subcontractors  be  used  by the
           Contractor in bidding and  performing  the work,  including,  but not
           limited to, WBE Electrical, WBE Telecom and Peerless Lighting.

           The Bid Package shall include the  Construction  Contract which shall
           be  provided by Tenant.  Landlord  shall have the right to review and
           approve the Construction Contract and make any necessary changes with
           respect to preserving and protecting Landlord's rights,  remedies and
           property.

           The Bid Package  shall be completed and accepted by both Landlord and
           Tenant no later than July 1, 1994. Each party shall have at least ten
           (10) working  days to review the Bid  Package.  Tenant will prepare a
           schedule  for  delivery  and review of the Bid  Package by January 1,
           1994.

     B.    Contractor:  The Contractor who shall perform the tenant  improvement
           work in the Premises  shall be selected  from two  bidders.  Landlord
           shall select one Contractor  and Tenant shall select one  Contractor.
           No later than June 1, 1994,  Landlord and Tenant  shall  provide each
           other  with the  name and  address  of their  respective  Contractor.
           Landlord  shall have  fourteen  (14) days to evaluate the  Contractor
           selected by Tenant.  Landlord's  criteria for  evaluation of Tenant's
           Contractor  shall  include,  but not be limited  to,  reputation  and
           quality  of  workmanship,  record  of  completing  previous  jobs  on
           schedule and within budget,  relationship with the City of San Rafael
           Building and Planning  Departments,  cooperativeness  in dealing with
           Landlord and its employees, financial strength and billing procedure.
           Tenant  shall  have  fourteen   (14)  days  to  evaluate   Landlord's
           Contractor. Tenant's criteria for evaluation of Landlord's Contractor
           shall include, but not be limited to, cost effectiveness,  quality of
           workmanship,  creativity,  record of completing  work on schedule and
           within budget,  and an  understanding  of Tenant's current and future
           requirements and a good working relationship with Tenant and Tenant's
           employees.  Landlord  and  Tenant  shall  each  use best  efforts  in
           ensuring that their evaluation process of each other's Contractors is
           fair and  reasonable.  A copy of the Bid Package may be given to each
           Contractor and may be used in evaluating the Contractor. Landlord and
           Tenant shall have the right to reject each other's  Contractor  based
           on any of the above  criteria or any other  relevant  criteria.  If a
           Contractor is rejected, the reasons for the rejection shall be stated
           in a letter to Landlord  or Tenant.  If a  Contractor  is rejected by
           Landlord or Tenant, another Contractor shall be selected and its name
           submitted in writing within five (S) days. Each  Contractor  shall be
           evaluated  using the same criteria  stated above.  Neither Tenant nor
           Landlord  may reject  more than three  Contractors  submitted  by the
           other.

           Landlord may submit its own name as a Contractor.

           As  soon  as  Landlord  approves  Tenant's  choice  of  a  Contractor
           ("Tenant's  Contractor")  and as soon as Tenant  approves  Landlord's
           choice of a Contractor ("Landlord's  Contractor") Tenant's Contractor
           and Landlord's  Contractor  shall be requested in writing to submit a
           bid on the Bid Package.  Ten (10)  working days after  receipt of the
           request for bid and the complete Bid Package,  both Contractors shall
           submit a sealed fixed price  contract bid (on such  contract  form as
           Landlord,  Tenant and  Architect  shall  designate)  to construct the
           tenant improvements specified in the Bid Package. Landlord and Tenant
           shall  jointly open and review the bids.  Landlord and Tenant  (after
           adjustments   for  any   inconsistent   assumptions   to  reflect  an
           "apples-to-apples"  comparison)  shall select the lowest price bidder
           as the Contractor  ("Contractor").  The Contractor shall enter into a
           construction  contract with Tenant  consistent  with the terms of the
           Bid Package and its bid to construct  the tenant  improvements.  That
           contract must state that Tenant shall hold Landlord harmless from any
           and all  liability  for the work to be  performed  under the terms of
           that construction contract.

           If Landlord's  Contractor is not selected as the  successful  bidder,
           Tenant shall pay Landlord or its  representative a reasonable owner's
           representation fee to compensate  Landlord for its time and effort in
           inspecting and overseeing the construction of the tenant  improvement
           work and assuring itself of good quality  materials and  workmanship,
           that the work contained in the Request for Disbursement (see Addendum
           1[1.D.)  is  complete,  and that  there is no  interference  with the
           day-to-day  operations  of  the  Building  as a  result  of  Tenant's
           construction.  The parties  agree that the maximum fee  chargeable by
           Landlord  shall be $50.00 per hour for up to five (5) hours per week.
           This fee shall be deducted from the Tenant Improvement Allowance (see
           Addendum to Lease 111.C.

     C.    Tenant Improvement Allowance: Landlord shall contribute Seven Hundred
           Sixty-two Thousand Two Hundred Twenty Dollars ($762,220.00) ($23.00 x
           33,140 usable SF) toward the construction of the tenant  improvements
           for Tenant's Premises ("Tenant  Improvement  Allowance").  The Tenant
           Improvement  Allowance shall include all  architectural,  engineering
           and consultant  fees, and all other fees charged in conjunction  with
           preparation  of the Bid  Package.  All  costs  exceeding  the  Tenant
           Improvement Allowance shall be borne by Tenant.

     D.    Disbursement  of Tenant  Improvement  Allowance:  Once a month, on or
           before the 10th day of the month,  Tenant shall present to Landlord a
           Request for  Disbursement  ("Request  for  Disbursement")  requesting
           payment  by  Landlord  of  any  costs  associated  with  the  design,
           engineering or construction of the tenant  improvements.  The Request
           for Disbursement shall include the following information:

           1)     A  certificate  from  Tenant  confirming  that all of the work
                  contained in the Request for  Disbursement  has been completed
                  in accordance with the applicable contracts.

           2)     A Certificate from Tenant's  Architect  confirming that all of
                  the work  contained in the Request for  Disbursement  has been
                  completed in  accordance  with the  applicable  contracts  and
                  certifying that materials have arrived on the job.

           3)     Unconditional  mechanics  lien releases and copies of invoices
                  from the Contractor, subcontractors, suppliers and materialmen
                  marked "Paid."

           4)     And such other reasonable documentation as may be requested by
                  Landlord not later than the 25th day of the previous month.

           Payment shall not be made on any Request for  Disbursement  until all
           of the information and documentation above is complete.

           Payment  shall be made  only for  those  materials  which  have  been
           installed  or which have been  delivered  to the  Premises.  Landlord
           shall  have five (5)  calendar  days from the date of  receipt of the
           Request for Disbursement to review same and request clarification. If
           Landlord is in Agreement with the Request for  Disbursement,  payment
           shall be made to  Tenant  within  ten  (10)  days of  receipt  of the
           Request for Disbursement. If any items are in dispute, Landlord shall
           not make  payment on those items until the dispute is  resolved,  but
           Landlord  shall make  payment to Tenant of all amounts not in dispute
           within  ten (10) days of  receipt of the  Request  for  Disbursement.
           Landlord shall not unreasonably  withhold its approval of any Request
           for Disbursement or on any specific request for payment made therein.
           A final  disbursement of Twenty-five  Thousand  Dollars  ($25,000.00)
           shall be held until all  punchlist  items in  Tenant's  Premises  are
           complete,  and the time for the filing of any mechanics liens claimed
           or which might be filed on account of any work  performed  by Tenant,
           Contractor, subcontractors,  suppliers or materialmen has passed. Any
           damage  to  Landlord's   property  will  be  repaired  to  Landlord's
           satisfaction.  Once  Landlord has  disbursed the entire amount of the
           Tenant Improvement  Allowance (See Addendum 1[1.C.) to Tenant, except
           the final  disbursement of $25,000.00,  any and all costs  associated
           with the design,  engineering or  construction  of Tenant's  Premises
           shall be paid directly by Tenant.

     E.    Change  Orders:  Tenant  may,  but only by  written  instructions  or
           drawings issued to Landlord and Contractor  ("Change Order Request"),
           make  changes to the work  specified  in the Bid  Package,  including
           without limitation, requiring additional work, directing the omission
           of work  previously  ordered or changing  the quantity or type of any
           materials,  equipment or services.  Promptly upon receipt of a Change
           Order  Request,  Contractor  will provide  Tenant with a statement in
           detail  setting forth the cost of said change  (including a breakdown
           of costs attributable to labor and materials,  construction equipment
           exclusively necessary for the change, and preparation or amendment to
           shop  drawings  resulting  from  said  change  and  any  time  delays
           anticipated  to result  from said  change).  Tenant will have two (2)
           days after  receipt of such  statement in which to confirm the Change
           Order  Request and  authorize the work to be performed or to withdraw
           such request.  Change Orders will be signed by Landlord and Tenant in
           advance of any work being performed on a Change Order.

     F.    Substantial  Completion:  For  purposes of this  Lease,  "Substantial
           Completion" shall mean that  construction of the tenant  improvements
           has been  completed in  accordance  with the Bid Package,  except for
           minor  finishing  details  of  construction,  decoration,  mechanical
           adjustment,  minor replacement of defective or damaged materials, and
           other items of a type commonly found on architectural punchlists, all
           of which do not  materially  interfere  with the occupancy and use of
           the  Premises  by Tenant or with  Tenant's  ability to  complete  the
           improvements  to the Premises to be made by Tenant.  Within three (3)
           days of  Substantial  Completion  Tenant's,  Architect  shall  notify
           Landlord in writing that the Premises are Substantially  Complete. If
           Tenant is  conducting  business in any part of the Premises the space
           shall be automatically deemed Substantially Complete.

           Within ten (10)  calendar  days after  Substantial  Completion of the
           tenant  improvements,  Tenant,  accompanied by Landlord or Landlord's
           representative,  shall make an inspection of the Premises and prepare
           a  punchlist  of items  needing  additional  work by the  Contractor.
           Contractor shall complete all punchlist items  reasonably  identified
           by Tenant or  Landlord  within  thirty (30)  calendar  days after the
           inspection  or as soon as  practicable  thereafter.  If  there is any
           dispute as to whether  Contractor  has  substantially  completed  the
           work, a good faith decision of Tenant's  Architect shall be final and
           binding on the parties.

     G.    Standard  of  Construction:  Contractor  shall  complete  all work in
           accordance  with the Bid Package  approved by Landlord and Tenant and
           shall  make  no  alterations,  additions,  or  reinforcements  to the
           structure of the building except as specifically approved by Landlord
           in the Bid package, or in writing thereafter.  Tenant, or Contractor,
           at its expense, shall procure all building and other permits required
           for completion of Tenant's work.  Tenant agrees that all work done by
           Tenant, its Contractor and subcontractors  shall be performed in full
           compliance  with  all  laws,  rules,  orders,  permits,   ordinances,
           directions,   regulations  and   requirements  of  all   governmental
           agencies,  offices,  and departments having  jurisdiction,  including
           without  limitation   applicable  provisions  pertaining  to  use  of
           hazardous or toxic  materials  and the  Americans  with  Disabilities
           Ac't,  and in full  compliance  with the rules,  orders,  directions,
           regulations and requirements of the Board of Fire Underwriters or any
           other organization performing a similar function.

           Landlord  shall have the right to enter the  Premises  at any time to
           post any Notice of Non-Responsibility or other notice on the Premises
           during  Tenant's  construction.  Contractor and all  contractors  and
           subcontractors retained by Tenant or Contractor shall be bondable and
           bonded,  licensed  contractors,   possessing  good  labor  relations,
           adequate  financials,   and  with  a  record  of  performing  quality
           workmanship.

           During the course of  construction,  Tenant shall maintain  builder's
           risk  insurance  in  form  and  content  reasonably  satisfactory  to
           Landlord.  Tenant's  insurance  shall name  Landlord as an additional
           insured  and shall  provide  that it may not be  canceled  or amended
           without twenty (20) days prior written  notice to Landlord.  At least
           seven (7) calendar days prior to commencement of construction, Tenant
           shall  provide  Landlord  with a  certificate  of such  insurance and
           evidence of any required bonds in form satisfactory to Landlord.

           Contractor shall complete the tenant  improvement work with diligence
           and in such a manner as not to interfere with the use or enjoyment of
           other  portions of the  Project or common  areas by Landlord or other
           tenants.  Contractor shall provide for all temporary power, water and
           other  utility   facilities  as  required  in  connection   with  the
           construction  of  Tenant's  work.  Contractor  shall  provide its own
           dumpster for collection and disposition of construction debris, which
           shall  be  located  at a  location  approved  by  Landlord,  and  all
           construction  debris  from  construction  shall  be  disposed  of  in
           Contractor's  dumpster and not in trash  facilities  for the Project.
           Contractor's  construction  materials,  tools,  equipment  and debris
           shall be stored only within the Premises,  or in areas designated for
           that purpose by Landlord.  Work space  exterior to the Premises shall
           be available  only with the written  approval of  Landlord.  Tenant's
           construction  work shall be subject to the inspection and supervision
           of Landlord and Landlord's representatives.

           Tenant and Contractor shall indemnify and hold harmless  Landlord for
           any and all claims arising from Tenant's  work.  Tenant shall pay for
           all damage to the  Building,  the Project,  or  appurtenant  areas or
           equipment,  as well as all damage to tenants or occupants  thereof or
           their licensees, or invitees,  including,  but not limited to, losses
           incurred  as the  result  of power  outages  caused  by  Tenant's  or
           Contractor's  work in the Building.  Any such damages may be deducted
           from the Tenant Improvement Allowance.

     H.    Liability:  The parties acknowledge that Landlord is not an architect
           or engineer and that the tenant  improvement work will be designed by
           independent  Architects,  Engineers  and  Consultants.   Accordingly,
           Landlord  does  not  guarantee  or  warrant  that any part of the Bid
           Package will be free from errors or  omissions,  and  Landlord  shall
           have no liability therefor.

           Tenant shall be solely  responsible  for the adequacy in all respects
           of the Bid Package,  including without limitation compliance with all
           governmental requirements, compatibility with the building shell, and
           any special  requirements of Tenant's proposed  equipment or machines
           with respect to ambient  temperatures,  electrical use or current, or
           water availability.  Landlord shall warrant only that the information
           provided  regarding  the base  building  (referred  to in Addendum to
           Lease  111.A.)  is true and  correct  to the  best of its  knowledge.
           Tenant  acknowledges  that in connection  with  obtaining  Landlord's
           approval of the Bid Package, Tenant may provide Landlord with certain
           information  regarding its specific needs relating to the Premises in
           developing plans and specifications for Tenant's work and that Tenant
           may  provide  some  of its  own  equipment  for  installation  in the
           Premises.  Tenant  further  acknowledges  that  Landlord will make no
           independent review of any such information and that Landlord does not
           warrant,  either  expressly  or  impliedly,  the  adequacy of the Bid
           Package for Tenant's  requirements or Tenant's equipment for Tenant's
           intended purpose.

     I.    Ownership of Tenant Improvements:  Upon termination of the Lease, all
           of the  tenant  improvements  shall  remain  in the  Premises  unless
           Landlord  shall consent in writing to the removal  thereof by Tenant.
           However,  all  Tenant's  trade  fixtures,  equipment,  furniture  and
           personal property shall remain the property of Tenant.

     J.    Life Safety: With respect to Life Safety System, Landlord believes to
           the best of its knowledge  that Regency Center meets all current code
           requirements  including  handicap  access  compliance.  If  any  code
           requirements  are not met with respect to the Building's  Life Safety
           System all costs to  accomplish  changes  necessary  to the  Building
           shall be covered by Landlord.  All code compliance costs with respect
           to  Tenant's  Premises  shall be covered  by the  Tenant  Improvement
           Allowance or by Tenant.

     K.    Use of  Current  Fixtures  in Space:  Tenant  shall have the right to
           reuse  the  fixtures  currently  in the  Premises  including  but not
           limited  to  all  cafeteria   built-ins,   the  moveable   partitions
           (retractable  wall) in the training rooms and fire  extinguishers and
           cases.  The food trolley  located in the  cafeteria and the equipment
           purchased or leased by the previous Tenant including, but not limited
           to, the cafeteria  tables and chairs,  ice  dispenser,  training room
           tables,  chairs,  white boards,  projection  screen,  reception desk,
           counter and hutch are not part of the fixtures in the Premises.


3.   POSSESSION

     A.    Possession  of the  Premises  ("Possession")  shall be  delivered  to
           Tenant no later than October 1, 1994 for the purpose of  constructing
           the  tenant  improvements.  If  possession  of the  space  cannot  be
           delivered by Landlord by that date, for any reason  whatsoever,  this
           Lease shall not be void or voidable,  nor shall Landlord be liable to
           Tenant  for any loss or  damage  resulting  therefrom,  nor shall the
           expiration  date of the term of Lease be in any way extended,  but in
           that event, of Commencement Date (as defined in Addendum 14.A.) shall
           be  extended  by the  exact  number  of days of  Landlord's  delay in
           delivering  possession.  Landlord  shall inform Tenant of the date of
           Possession in writing at least thirty (30) days prior to Possession.

     B.    If  Landlord  shall not have  delivered  Possession  of the  Premises
           within  ninety (90) days after the  Commencement  Date (as defined in
           Addendum  1[4.A.),  Tenant  may,  at  Tenant's  option,  by notice in
           writing to  Landlord  within ten (10) days  thereafter,  cancel  this
           Lease,  in which  event  the  parties  shall be  discharged  from all
           obligations hereunder; provided, however, that if such written notice
           by  Tenant  is not  received  by  Landlord  within  said ten (10) day
           period, Tenant's right to cancel this lease hereunder shall terminate
           and be of no further force or effect.


4.   COMMENCEMENT

     A.    If Possession is delivered on October 1, 1994 the  Commencement  Date
           ("Commencement")  shall be  defined as  December  1, 1994 or five (5)
           days after Substantial  Completion of the tenant improvement work (as
           defined in Addendum  111.E.)  whichever is earlier.  If Possession is
           delivered  prior to October 1, 1994, the  Commencement  Date shall be
           sixty (60)  calendar  days after the date of  Possession  or five (5)
           days after  Substantial  Completion of the tenant  improvement  work,
           whichever is earlier.

           Landlord  shall notify  Tenant in writing of the actual  Commencement
           Date no later than thirty (30) days after Substantial Completion.  In
           the event  Substantial  Completion is delayed by Tenant Caused Delays
           (as  defined in  Addendum  1[4.C.)  the same  number of days shall be
           deducted  from total  number of days of the  build-out  and that date
           shall be the Commencement.


5.   FREE RENT

     Landlord shall allow Tenant and Contractor to occupy and perform the tenant
     improvement  work in the Premises  without payment of rent after Possession
     (as defined in Addendum 1[3) for a period of two (2) months. Landlord shall
     allow Tenant to occupy one-half (1/2) of the Premises (approximately 17,630
     rentable  square  feet)  for six (6)  months  after the  Commencement  Date
     without payment of rent. Tenant's first month's rent paid upon execution of
     this Lease  shall  cover the rent on the  remaining  one-half  (1t2) of the
     Premises for the first two (2) months after the Commencement Date.



6.   OPERATING EXPENSE ADJUSTMENTS  (Continued from Article 7 of the Lease.)

     A.    During  the  initial  term of this  Lease,  management  costs for the
           building  shall not exceed  three  percent  (3%) of the gross  rental
           income for the building.

     B.    Landlord shall keep full, accurate, and separate books of account and
           records  covering  all Direct  Expenses,  which books of accounts and
           records  shall  accurately  reflect the total  Direct  Expenses,  and
           Landlord's billings to Tenant for Operating Expense Adjustments.

     C.    Tenant  shall  have the  right to  protest  any  charge  to Tenant by
           Landlord  for  Operating  Expense  Adjustments,  provided  that  said
           protest is made within  thirty (30) days after  receipt of Landlord's
           notice of such charge. In the event that Tenant shall protest, Tenant
           shall be entitled to audit Landlord's books of account,  records, and
           other pertinent data regarding  Direct  Expenses.  The audit shall be
           limited to the determination of direct Expenses and charges to Tenant
           for  Operating  Expense  Adjustments  and shall be  conducted  during
           normal  business  hours.  If the audit  shows  that there has been an
           overpayment by Tenant,  the overpayment  shall be immediately due and
           repayable by Landlord to Tenant.


7.   OPTION TO EXTEND

     A.    Landlord grants to Tenant the option to extend the term of this Lease
           for two 3-year  periods  commencing  when the prior term expires upon
           each and all of the following terms and conditions:

           (i)    Tenant gives to Landlord and Landlord  receives  notice of the
                  exercise   of  the  option  to  extend  this  Lease  for  said
                  additional  term no later than twelve (12) months prior to the
                  time that the option period would  commence if the option were
                  exercised,  time being of the essence. If said notification of
                  the exercise of said option is not so given and received, this
                  option shall automatically expire;

           (ii)   At the time said written notification of exercise of option is
                  given and  received,  Tenant shall not be in default under any
                  of the material  obligations  of this Lease to be performed by
                  Tenant and this Lease shall not have previously terminated nor
                  terminated prior to the commencement of the option term;

           (iii)  All of the terms and  conditions  of this Lease  except  where
                  specifically modified by this option shall apply;

           (iv) The monthly  rent for each month of the option  period  shall be
calculated as follows:

           The rent payable by Tenant  during the first  option  period shall be
           the Fair Market  Rental Value of the  Premises (as defined  below) at
           the commencement date of the option period.  There shall be an annual
           C.P.I.  increase not to exceed four  percent (4%) in each  subsequent
           year of the first  option  period.  The rent in the first year of the
           second  option period shall be the rent in the last year of the first
           option period to which will be added a C.P.I.  increase not to exceed
           four percent (4%).  There shall be an annual  C.P.I.  increase not to
           exceed four percent (4%) in each subsequent year of the second option
           period.  All of the C.P.I.  increases during the option periods shall
           be  calculated  on the basis of the  formula  provided in the Lease 1
           5.B. If Landlord and Tenant  cannot  agree on the Fair Market  Rental
           Value of the Premises for the  extension  periods  within  forty-five
           (45) days after the Tenant has  notified  Landlord of its exercise of
           the option,  Landlord and Tenant shall each select, within forty-five
           (45) days of such notification,  an appraiser who must be a qualified
           M.A.I.  appraiser to determine said Fair Market Rental Value.  If one
           party fails to so designate an  appraiser  within the time  required,
           the  determination  of Fair Market  Rental Value of the one appraiser
           who has been  designated  by the other party  hereto  within the time
           required  shall be binding upon both parties.  The  appraisers  shall
           submit  their  determinations  of Fair  Market  Rental  Value to both
           parties  within  thirty  (30)  days  after  their  selection.  If the
           difference  between the two  determinations  is ten percent  (10%) or
           less of the  higher  appraisal,  then  the  average  between  the two
           determinations shall be the Fair Market Rental Value of the Premises.
           If said  difference is greater than ten percent  (10%),  then the two
           appraisers  shall within  twenty (20) days of the date that the later
           submittal is submitted to the parties designate a third appraiser who
           must also be a qualified M.A.I. appraiser. The sole responsibility of
           the third appraiser will be to determine which of the  determinations
           made by the first  appraisers is most accurate.  The third  appraiser
           shall have no right to propose a middle ground or any modification of
           either of the  determinations  made by the first two appraisers.  The
           third  appraiser's  choice shall be  submitted to the parties  within
           thirty (30) days after his or her selection. Such determination shall
           bind both of the parties and shall  establish  the Fair Market Rental
           Value of the  Premises.  Each party shall pay for their own appraiser
           and shall pay an equal  share of the fees and  expenses  of the third
           appraiser.

           Fair  Market  Rental  Value for  purpose of this Lease shall mean the
           then prevailing rent for premises  comparable in size,  quality,  and
           orientation to the demised Premises,  located in buildings comparable
           in size to, and in the general  vicinity of, the  building  which the
           demised Premises are located, leased on terms comparable to the terms
           contained in this Lease.

8.   RIGHT OF  FIRST OPPORTUNITY TO LEASE ADDITIONAL PREMISES AT 100 SMITH RANCH
     ROAD, SAN RAFAEL

     At any time during the term  hereof,  or any options to extend which Tenant
     has  exercised,  provided that Tenant is not in default as defined  herein,
     Tenant  shall  have a right of First  Opportunity  to Lease for all  office
     space that becomes available for lease at 100 Smith Ranch Road, San Rafael,
     based on the terms and conditions as outlined below.

     Landlord  and Tenant  acknowledge  that there are  existing  tenants at 100
     Smith  Ranch Road,  which  tenants  have  options to renew or wish to renew
     their  respective  leases,  and that these existing options and requests to
     renew would take  precedent  over the Right of First  Opportunity  to Lease
     described herein.

     Landlord  and  Tenant  further   acknowledge   that  this  Right  of  First
     Opportunity  to Lease shall  apply only to  premises,  from which  existing
     tenants vacate or which is currently vacant.

     Landlord shall notify Tenant in writing of the  availability  of additional
     office premises at 100 Smith Ranch Road, San Rafael within thirty (30) days
     of Landlord  receiving  notice  from an existing  Tenant at 100 Smith Ranch
     Road of that Tenant's intent to vacate their premises. Landlord's notice to
     Tenant shall include the size of premises,  the projected date at which the
     premises  may  be  available,  and a  floor  plan  indicating  the  current
     configuration of the premises.

     Tenant  shall have ten (10) days after  receipt of notice from  Landlord to
     notify  Landlord of  Tenant's  intent to lease the  premises  which was the
     subject of the notice.  In the event  Landlord does not receive notice from
     Tenant of Tenant's  intent to lease said  available  space,  Landlord shall
     have the right to lease  said  space to any  other  Tenant  which  Landlord
     chooses,  and Tenant's  Right of First  Opportunity  to lease that specific
     premises shall be deemed waived.

     In the event Tenant notifies Landlord of its intent to lease said premises,
     Landlord  and Tenant  shall  proceed as soon as is  reasonably  possible to
     execute a lease agreement for the specific  premises that became available.
     Terms  and  conditions  of the Lease  shall be based on the same  terms and
     conditions  of the  lease(s)  on the other  space  Tenant  occupies  in the
     Building at the time the lease is executed.  Landlord and Tenant shall make
     a good faith  effort to execute a Lease for the  specific  available  space
     within thirty (30) days after Tenant has notified Landlord of its intent to
     lease said space.

     This Right of First Opportunity to Lease shall in no way limit the Landlord
     from  executing  leases  with new  tenants  for terms of any  length,  with
     options to renew for any length,  for those spaces for which Tenant has not
     exercised its Right of First Opportunity to lease as defined herein.



9.   SERVICES AND UTILITIES

     A.    Provided that Tenant is not in default hereunder,  Landlord agrees to
           furnish  to  the  Premises  five-day  per  week  janitorial  service.
           Landlord  shall  also  maintain  and  keep  lighted,  heated  and air
           conditioned during reasonable hours of generally  recognized business
           days, the common entries, common corridors,  common stairs and toilet
           rooms in the building of which  Premises are a part.  Landlord  shall
           not be liable for, and Tenant shall not be entitled to, any reduction
           of rental  by reason of  Landlord's  failure  to  furnish  any of the
           foregoing when such failure is caused by accident, breakage, repairs,
           strikes,  lockouts or other labor  disturbances  or labor disputes of
           any character,  or by any other cause, similar or dissimilar,  beyond
           the  reasonable  control of  Landlord.  Landlord  shall not be liable
           under any circumstances for a loss of or injury to property,  however
           occurring,  through or in connection with or incidental to failure to
           furnish any of the foregoing.

     B.    Tenant shall have 24-hour per day,  seven-day  per week access to its
           Premises.

     C.    Landlord  shall  provide  Tenant a  monthly  allowance  of  $3,878.71
           (35,261  rentable SF x $.11) for Tenant's  electrical  service.  This
           allowance is included in the Base Rent as defined in Article 5 of the
           Lease.

           Landlord and Tenant recognize that Tenant's  electrical service shall
           cost in excess  of $.11 per  square  foot per  month due to  Tenant's
           heavy electrical and air conditioning requirements.

           Tenant shall be charged for all PG&E charges to the building over and
           above the monthly  allowance  provided above,  less any over-standard
           charges to other  tenant's in the  building  (any usage over the $.11
           allowance  provided to each Tenant.) At the time of Lease  execution,
           no per square foot tenants in the Building  other than Fireman's Fund
           who   currently   occupies  the  entire   second   floor,   have  any
           over-standard  usage.  Landlord shall notify Tenant as to any changes
           in the existing tenant's  electrical usage or any over-standard usage
           of new  tenants  to the  building.  Tenant  may  at any  time  notify
           Landlord  that in Tenant's  view,  a  particular  tenant may be using
           over-standard  electrical  and Landlord will  investigate  that usage
           with the  assistance  of an  electrical  engineer and shall report to
           Tenant its  findings  regarding  the usage and shall charge the other
           tenant for any actual  over-standard  usage,  which  amount  shall be
           deducted  from  Tenant's  over-standard  charges.  If Tenant does not
           agree with Landlord or Landlord's engineer's calculation,  Tenant may
           have its own engineer evaluate the other tenant's usage.

           For the first  year of  Tenant's  occupancy,  Landlord  shall  charge
           Tenant  $.11 per  useable  square  foot per month  for  over-standard
           electrical usage as a projected  expense,  which amount is an average
           paid by Tenant in its other Premises  located at 111 Smith Ranch Road
           and 120 North Redwood Drive.  This amount  ($3,645.40)  shall be paid
           along  with  the  monthly  rent.  At the  end of the  first  year  of
           occupancy, Landlord shall prepare a PG&E invoice analysis showing the
           actual cost of over-standard  usage by Tenant.  Landlord shall credit
           Tenant  for  any  amounts  paid  in  excess  of the  actual  cost  of
           overstandard usage. Tenant shall pay Landlord for any costs in excess
           of the  total  projected  sum paid by Tenant  over the first  year of
           occupancy.  The amount  paid by Tenant for  over-standard  electrical
           usage for each  subsequent  year of  occupancy  shall be based on the
           previous year's charges and a similar accounting between Landlord and
           Tenant will occur annually.

     D.    The hours of operation of the heating and air conditioning system for
           the building are as follows:

                  Monday thru Friday:           7:00 a.m. to 6:00 p.m.
                  Saturdays:                    8:00 a.m. to 3:00 p.m.

     E.    In the event  Tenant  requires  the  operation of the heating and air
           conditioning  system  beyond the normal  hours of  operation  for the
           building,  Tenant shall notify the building manager in advance of the
           required  extended hour usage, and the building manager shall program
           the heating and air  conditioning  system to operate  during the time
           period requested by Tenant.

     F.    In the event  Tenant  shall  request  that an override  mechanism  be
           installed  during the term of the Lease, an override  mechanism shall
           be  installed  on the  heating  and  air  conditioning  system  which
           services Tenant's premises.  The cost of this mechanism shall be paid
           by the Tenant at the time of the  installation.  This mechanism shall
           allow  Tenant to have  control of the  heating  and air  conditioning
           system for its premises in hours other than the normal building hours
           stated above.

           Along with the override mechanism,  an hourly meter shall be attached
           to the override  mechanism  which shall  measure  Tenant's use of the
           heating and air conditioning system beyond the normal building hours.
           On a monthly  basis,  Landlord  shall charge Tenant for this usage by
           multiplying  the  number  of hours  used by the per hour  charge  for
           operating  the heating  and air  conditioning  system  which shall be
           determined  by  Landlord's  electrical  engineer  and heating and air
           conditioning contractor.





10.  COMMUNICATIONS INSTALLATION

     Tenant has installed  certain  communications  equipment on the roof of the
     Building.

     Prior to the end of the term of this Lease,  Tenant,  at Tenant's sole cost
     and expense, shall remove the communications equipment and shall, forthwith
     and with all due  diligence,  repair any damage to the  Premises  caused by
     such removal.


11.  CONSENT

     Landlord  and Tenant  agree  that in the event  their  consent is  required
     pursuant  to the  provisions  of  the  Lease,  such  consent  shall  not be
     unreasonably withheld.


       LANDLORD                The Joseph and Eda Pell Revocable Trust

                               By:    /s/Joseph Pell
                                      ------------------------------
                                         Joseph Pell


                               Its:
                                      ------------------------------



                               By:    /s/ Eda  Pell
                                      ------------------------------
                                          Eda Pell


                               Its:
                                      ------------------------------



                               Date:  March 30, 1994


       TENANT                  Fair, Isaac and Company, Incorporated

                               By:    /s/ Robert D. Sanderson
                                      ------------------------------



                               Its:   Executive Vice President
                                      ------------------------------



                               Date:  March 10, 1994



                                                                   EXHIBIT 10.30

                            SECOND ADDENDUM TO LEASE
                                 BY AND BETWEEN
                     THE JOSEPH AND EDA PELL REVOCABLE TRUST
                                ("THE LANDLORD")
                                       AND
                      FAIR, ISAAC AND COMPANY, INCORPORATED
                                 ("THE TENANT")

         This  Second  Addendum  to  Lease  dated  November  22,  1996  ("Second
Addendum"),  is hereby attached to and incorporated into and made a part of that
Lease dated July 10,  1993,  by and  between  The Joseph and Eda Pell  Revocable
Trust and Fair,  Isaac and Company,  Incorporated as amended by a First Addendum
to Lease dated July 10, 1993 ("the  Lease").  The parties agree to the following
terms and conditions set forth herein below:

Recitals

         A. Landlord and Tenant are parties the Lease pursuant to which Landlord
leased to Tenant  and  Tenant  leased  from  Landlord  office  space  containing
approximately  35,261  rentable  square  feet and  33,140  useable  square  feet
comprising part of the of the Second Floor of that certain office building known
as Regency  Center I ("Regency I") located at 100 Smith Ranch Road,  San Rafael,
California ("the Premises").

         B. Landlord is currently constructing a building adjacent to Regency I,
which new building will be known as Regency  Center II, and which will be leased
in its  entirety  to Tenant  pursuant to an Office  Building  Lease of even date
herewith.

         C. Landlord and Tenant now desire to amend the Lease as hereinafter set
forth.

         D. The capitalized terms herein, unless otherwise indicated, shall have
the meanings ascribed to them in the Lease.

         NOW, THEREFORE,  for good and valuable  consideration,  the receipt and
sufficiency of which are hereby acknowledged, the parties agree as follows:

         1. Paragraph 8 ("Right of First  Opportunity") of the First Addendum to
Lease is hereby deleted in its entirety.

         2. Subparagraph A and  sub-subparagraph  (i) of Paragraph 7 ("Option to
Extend")  of the First  Addendum to Lease are hereby  deleted and the  following
substituted therefor:

"A.  Landlord  grants to Tenant  the option to extend the term of this Lease for
the  Existing  Premises  for  one (1)  ten  (10)  year  period  commencing  upon
expiration of the Term for the lease of the Existing Premises, upon each and all
of the following terms and conditions:"

"(i) Tenant gives to Landlord and  Landlord  receives  notice of the exercise of
the option to extend  this Lease for said  additional  term no later than twelve
(12)  months  prior to the time that the option  period  would  commence  if the
option were exercised,  time being of the essence.  If said  notification of the
exercise  of said  option  is not so  given  and  received,  this  option  shall
automatically expire;"

         3. Except as set forth herein, the Lease shall remain unmodified and in
full force and effect.  Should  there by any  conflict  between the terms of the
Lease and the terms of this Second  Addendum,  the terms of this Second Addendum
shall control.

         IT WITNESS  WHEREOF,  the parties have executed this Second Addendum to
Lease as of the date first written above.


                                 The Joseph and Eda Pell Revocable Trust

                                 By:  /s/ Joseph Pell
                                      ---------------------------------
                                 Joseph Pell, Trustee

                                 By:  /s/ Eda Pell
                                      ---------------------------------
                                 Eda Pell, Trustee

                                 Fair, Isaac and Company, Incorporated

                                 By:  /s/ Michael C. Gordon
                                      ---------------------------------
                                 Vice President