Exhibit 10.18

                              OFFICE BUILDING LEASE


1.     PARTIES This Lease, dated, for reference purposes only, October 11, 1993,
       is made by and between The Joseph and Eda Pell  Revocable  Trust  (herein
       called  "Landlord")  and Fair,  Isaac and Company,  Incorporated  (herein
       called "Tenant").

2.     PREMISES  Landlord  does hereby lease to Tenant and Tenant  hereby leases
       from  Landlord  that certain  office  space  (herein  called  "Premises")
       indicated on Exhibit "A"  attached  hereto and  reference  thereto made a
       part hereof,  said Premises being agreed, for the purposes of this Lease,
       to have an area of  approximately  4,007  rentable  square feet and 3,506
       useable  square feet,  being  situated in Suite 124 on the first floor of
       that certain Building known as Regency Center,  100 Smith Ranch Road, San
       Rafael, CA 94903.

       Said Lease is subject to the terms,  covenants and conditions  herein set
       forth and the Tenant  covenants as a material  part of the  consideration
       for this Lease to keep and perform each and all of said terms,  covenants
       and  conditions  and that this Lease is made upon the  condition  of said
       performance.

3.     TERM The term of this Lease  shall be for seven (7) years and eleven (11)
       months,  commencing  on the 1st day of January,  1994,  and ending on the
       30th day of November, 2001.

4.     POSSESSION  See Addendum to Lease  P.5, Possession.

5.     A.    RENT Tenant  agrees to pay to Landlord as rental for the  premises,
             without prior notice or demand,  the sum of Eight Thousand Fourteen
             Dollars  ($8,014.00)  on or before  the first day of the first full
             calendar  month of the term  hereof and a like sum on or before the
             first day of each and every  successive  calendar month  thereafter
             during the term hereof, except that the first month's rent shall be
             paid upon the  execution of this Lease.  Rent for any period during
             the term  which is for less than one (1) month  shall be a prorated
             portion of the monthly installment herein, based upon a thirty (30)
             day month.  Said rental shall be paid to Landlord without deduction
             or offset in lawful  money of the United  States of America,  which
             shall be legal  tender at the time of  payment  at 100 Smith  Ranch
             Road,  Suite 325, San Rafael,  California  94903,  or to such other
             place as Landlord may from time to time designate in writing.

       B.    RENT  ESCALATIONS  Commencing  on the  11th  month  of  this  Lease
             (December 1, 1994) and on each annual  anniversary  following,  the
             base  rent  shall  be  adjusted  by the  increase,  if any,  in the
             Consumer Price Index of the Bureau of Labor Statistics of the U. S.
             Department    of   Labor    for   All    Urban    Consumers,    San
             Francisco-Oakland-San Jose (1984=100),  "All Items" herein referred
             to as "C. P.I."

             The C. P.I. increase shall be calculated as follows:  The base rent
             payable for the first month term of this Lease shall be  multiplied
             by the percentage change in the C. P.I. for the 12 months preceding
             December 1, 1994 On each anniversary following, the base rent shall
             be  multiplied by the  percentage  change in the C. P.I. for the 12
             months  preceding.  No  single  increase  shall  exceed  4% of  the
             previous  year's  rental rate and in no event shall the new monthly
             rent be less  than  the  rent  payable  for the  month  immediately
             preceding the date for rent adjustment.

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6.     SECURITY  DEPOSIT  Tenant has  deposited  with  Landlord the sum of Eight
       Thousand Fourteen Dollars ($8,014.00). Said sum shall be held by Landlord
       as  security  for the  faithful  performance  by Tenant of all the terms,
       covenants,  and  conditions  of this  Lease to be kept and  performed  by
       Tenant  during the term hereof.  If Tenant  defaults  with respect to any
       provision  of this Lease  including,  but not limited to, the  provisions
       relating to the payment of rent,  Landlord may (but shall not be required
       to) use, apply or retain all or any part of this security deposit for the
       payment of any rent or any other sum in  default,  or for the  payment of
       any  amount  which  Landlord  may spend or become  obligated  to spend by
       reason of Tenant's  default to compensate  Landlord for any other loss or
       damage which  Landlord may suffer by reason of Tenant's  default.  If any
       portion of said deposit is so used or applied,  Tenant shall, within five
       (5) days after written demand therefor,  deposit cash with Landlord in an
       amount  sufficient to restore the security deposit to its original amount
       and Tenant's  failure to do so shall be a material  breach of this Lease.
       Landlord  shall not be required to keep this  security  deposit  separate
       from its  general  fund and Tenant  shall not be  entitled to interest on
       such  deposit.  If  Tenant  shall  fully  and  faithfully  perform  every
       provision of this Lease to be  performed  by it, the security  deposit or
       any balance  thereof  shall be  returned  to Tenant  (or,  at  Landlord's
       option,  to the last  assignee of  Tenant's  interest  hereunder)  at the
       expiration of the Lease term. In the event of  termination  of Landlord's
       interest  in  this  Lease,   Landlord  shall  transfer  said  deposit  to
       Landlord's successor in interest.

7.     OPERATING  EXPENSE  ADJUSTMENTS  For the  purposes of this  Article,  the
       following terms are defined as follows:

       Base Year           The Base Year shall be 1994.

       Comparison Year     Each calendar year of the term after the Base Year.

       Direct Expenses     All direct costs of  operation  and  maintenance,  as
                           determined   by   standard   accounting    practices,
                           including the following costs by way of illustration,
                           but  not be  limited  to:  real  property  taxes  and
                           assessments;   rent  taxes,   gross  receipt   taxes,
                           (whether  assessed  against the  Landlord or assessed
                           against the Tenant and collected by the Landlord,  or
                           both); water and sewer charges;  insurance  premiums;
                           utilities; janitorial services; labor; costs incurred
                           in the management of the Building; air conditioning &
                           heating; elevator maintenance;  supplies;  materials;
                           equipment  and  tools;  and  maintenance,  costs  and
                           upkeep of all  parking  and  common  areas.  ("Direct
                           Expenses"  shall  not  include  depreciation  on  the
                           Building  of  which  the   Premises  are  a  part  or
                           equipment therein, loan payments,  executive salaries
                           or real estate broker's commissions.)

       If the  Direct  Expenses  paid  or  incurred  by  the  Landlord  for  the
       Comparison  Year  on  account  of the  operation  or  maintenance  of the
       Building  of which the  Premises  are a part are in excess of the  Direct
       Expenses  paid or incurred  for the Base Year,  then the Tenant shall pay
       3.9% of the  increase.  This  percentage  is that  portion  of the  total
       rentable area of the Building occupied by the Tenant hereunder.  Landlord
       shall  endeavor  to give to Tenant on or before the first day of March of
       each year  following the  respective  Comparison  Year a statement of the
       increase in rent payable by Tenant hereunder,  but failure by Landlord to
       give  such  statement  by said  date  shall  not  constitute  a waiver by
       Landlord of its right to require an increase in rent. Upon receipt of the
       statement  for the first  Comparison  Year,  Tenant shall pay in full the
       total amount of the increase  due for the first  Comparison  Year and, in
       addition for the then current year, the amount of any such increase shall
       be used as

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       an estimate  for said  current year and this amount shall be divided into
       twelve (12) equal monthly  installments and Tenant shall pay to Landlord,
       concurrently with the regular monthly rent payment next due following the
       receipt of such statement, an amount equal to one (1) monthly installment
       multiplied  by the number of months from January in the calendar  year in
       which said  statement  is submitted  to the month of such  payment,  both
       months inclusive.  Subsequent  installments shall be payable concurrently
       with the regular  monthly rent  payments for the balance of that calendar
       year and shall continue  until the next  Comparison  Year's  statement is
       rendered.  If the next or any  succeeding  Comparison  Year  results in a
       greater  increase in Direct  Expenses,  then upon  receipt of a statement
       from  Landlord,  Tenant shall pay a lump sum equal to such total increase
       in Direct  Expenses  over the Base  Year,  less the total of the  monthly
       installments  to be paid for the next  year,  following  said  Comparison
       Year,  shall be adjusted to reflect such  increase.  If in any Comparison
       Year the  Tenant's  share of Direct  Expenses be less than the  preceding
       year, then upon receipt of Landlord's statement,  any overpayment made by
       Tenant on the monthly  installment basis provided above shall be credited
       towards  the next  monthly  rent  falling due and the  estimated  monthly
       installments  of Direct  Expenses to be paid shall be adjusted to reflect
       such lower Direct Expenses for the most recent Comparison Year.

       Even though the term has  expired  and Tenant has  vacated the  Premises,
       when the final determination is made of Tenant's share of Direct Expenses
       for the year in which this Lease terminates, Tenant shall immediately pay
       any increase due over the  estimated  expenses  paid and  conversely  any
       overpayment made in the event said expenses decrease shall be immediately
       rebated by Landlord to Tenant.

       Notwithstanding  anything contained in this Article,  the rent payable by
       Tenant  shall in no event be less than the rent  specified  in  Article 5
       hereinabove.

       See Addendum to Lease, P. 1 , Operating Expense Adjustments.

8.     USE Tenant shall use the Premises for general  office  purposes and shall
       not use or permit the Premises to be used for any other purposes  without
       the prior written consent of Landlord.

       General  office  purposes  shall be defined for purposes of this Lease to
       include computer rooms of any size required by Tenant.

       Tenant  shall  not do or  permit  anything  to be  done in or  about  the
       Premises  nor  bring  or  keep  anything  therein  which  will in any way
       increase the existing rate of or affect any fire or other  insurance upon
       the  Building  or any of  its  contents,  or  cause  cancellation  of any
       insurance policy covering said Building or any part thereof or any of its
       contents.  Tenant shall not do or permit  anything to be done in or about
       the Premises  which will in any way obstruct or interfere with the rights
       of other  tenants or occupants of the Building on injure or annoy them or
       use or allow the Premises to be used for any improper,  immoral, unlawful
       or objectionable  purpose, nor shall Tenant cause, maintain or permit any
       nuisance in, on or about the Premises.  Tenant shall not commit or suffer
       to be committed any waste in or upon the Premises.

9.     COMPLIANCE  WITH LAW Tenant shall not use the Premises or permit anything
       to be done in or about the Premises  which will in any way conflict  with
       any law,  statute,  ordinance or  governmental  rule or regulation now in
       force or which may hereafter be enacted or promulgated.  Tenant shall, at
       its sole cost and  expense,  promptly  comply  with

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       all laws,  statutes,  ordinances and  governmental  rules now in force or
       which may hereafter be in force,  and with the  requirements of any board
       of fire insurance  underwriters  or other similar bodies now or hereafter
       constituted, relating to, or affecting the condition, use or occupancy of
       the  Premises,  excluding  changes not related to or affected by Tenant's
       improvements or acts. The judgment of any court of competent jurisdiction
       or the admission of Tenant in any action against Tenant, whether Landlord
       be a party  thereto or not,  that Tenant has violated  any law,  statute,
       ordinance or  governmental  rule,  regulation  or  requirement,  shall be
       conclusive of that fact as between the Landlord and Tenant.

10.    ALTERATIONS AND ADDITIONS  Tenant shall not make or suffer to be made any
       alterations,  additions or improvements to or of the Premises or any part
       thereof  without the written  consent of Landlord first had and obtained.
       Any  alterations,  additions  or  improvements  to  or of  said  Premises
       including,  but not limited to, wallcovering,  paneling, air conditioning
       units and built-in  cabinet  work,  but excepting  movable  furniture and
       trade fixtures,  shall on the expiration of the term become a part of the
       realty  and  belong to the  Landlord  and shall be  surrendered  with the
       Premises.   In  the  event  Landlord   consents  to  the  making  of  any
       alterations,  additions or  improvements  to the Premises by Tenant,  the
       same shall be made by Tenant at Tenant's  sole cost and expense,  and any
       contractor or persons  selected by the Tenant to make the same must first
       be  approved  in  writing by the  Landlord.  Such  approval  shall not be
       unreasonably  withheld.  Upon the expiration or sooner termination of the
       term hereof, Tenant shall, upon written demand by Landlord which shall be
       given at the time  Landlord  approves the tenant  improvement  work, , at
       Tenant's  sole cost and expense,  forthwith  and with all due  diligence,
       remove  any  alterations,  additions,  or  improvements  made by  Tenant,
       designated  by Landlord to be removed,  and Tenant  shall,  forthwith and
       with all due diligence at its sole cost and expense, repair any damage to
       the Premises caused by such removal.

11.    REPAIRS

       A.    By taking  possession  of the  Premises,  Tenant shall be deemed to
             have  accepted  the  Premises  as being in  good,  sanitary  order,
             condition  and repair.  Tenant  shall,  at  Tenant's  sole cost and
             expense, keep the Premises and every part thereof in good condition
             and repair damage thereto from causes beyond the reasonable control
             of Tenant with ordinary wear and tear  excepted.  Tenant shall upon
             the expiration or sooner termination of this Lease hereof surrender
             the Premises to the Landlord in good  condition,  ordinary wear and
             tear and damage from causes beyond the reasonable control of Tenant
             excepted.  Except as specifically  provided in an addendum, if any,
             to this Lease,  Landlord  shall have no  obligation  whatsoever  to
             alter, remodel,  improve, repair, decorate or paint the Premises or
             any part thereof once the initial tenant improvements are completed
             and  the  parties   hereto   affirm  that   Landlord  has  made  no
             representations  to Tenant respecting the condition of the Premises
             or the Building except as specifically herein set forth.

       B.    Notwithstanding  the  provisions  of  Article  11. A.  hereinabove,
             Landlord shall repair and maintain the  structural  portions of the
             Building,  including the basic plumbing, air conditioning,  heating
             and electrical  systems  installed or furnished by Landlord  unless
             such  maintenance and repairs are caused in part or in whole by the
             act,  neglect,  fault or omission  of any duty by the  Tenant,  its
             agents, servants, employees or invitees, in which case Tenant shall
             pay to  Landlord  the  reasonable  cost  of  such  maintenance  and
             repairs.  Landlord  shall not be liable for any failure to make any
             such  repairs or to perform any  maintenance  unless  such  failure
             shall persist for an unreasonable  time

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             after written  notice of the need of such repairs or maintenance is
             given to  Landlord  by  Tenant.  Except as  provided  in Article 22
             hereof,  there shall be no  abatement  of rent and no  liability of
             Landlord by reason of any injury to or  interference  with Tenant's
             business  arising  from the making of any repairs,  alterations  or
             improvements  in or to any portion of the Building or the Premises,
             or in or to fixtures,  appurtenances and equipment therein.  Tenant
             waives the right to make repairs at  Landlord's  expense  under any
             law, statute or ordinance now or hereafter in effect (including the
             provisions of California  Civil Code Sections 1941 and 1942 and any
             successor  sections  or statutes  of a similar  nature);  provided,
             however,  if Landlord  fails to perform any repair work required of
             Landlord with respect to the Premises  pursuant to this  Paragraph,
             within thirty (30) days after Landlord  receives  Tenant's  written
             notice  of the need  for such  repair  (or such  period  of time in
             excess of thirty (30) days as is  reasonably  necessary  based upon
             the nature of the required work), then Tenant shall be permitted to
             make  such  repairs,   using  contractors  reasonably  approved  by
             Landlord,  provided (i) Tenant first gives  Landlord an  additional
             two (2) business days' prior written notice  indicating that Tenant
             intends  to  undertake  such  repair,  and (ii)  Landlord  fails to
             commence  such repair  within such two (2) business day period.  If
             Tenant  performs  any repair as  permitted  under  this  Paragraph,
             Landlord agrees to reimburse Tenant for the reasonable,  actual and
             documented  costs of such repair  performed by Tenant,  but without
             any off-set  rights  against rent or any other  amounts  payable by
             Tenant  under this Lease.  Any repair work done by Tenant  shall be
             done in accordance  with the  provisions  of this Lease,  including
             without  limitation,  Paragraph 12,  keeping the premises free from
             liens.

12.    LIENS  Tenant  shall  keep the  Premises  and the  property  in which the
       Premises  are  situated  free  from  any  liens  arising  out of any work
       performed,   materials  furnished  or  obligations  incurred  by  Tenant.
       Landlord  may  require,  at  Landlord's  sole  option,  that Tenant shall
       provide  to  Landlord,  at  Tenant's  sole cost and  expense,  a lien and
       completion bond in an amount equal to one and one-half  (1-1/2) times any
       and all estimated  cost of any  improvements,  additions or alteration in
       the Premises to insure Landlord  against any liability for mechanics' and
       materialmen's liens and to insure completion of the work.

13.    ASSIGNMENT  AND  SUBLETTING  Tenant  shall not either  voluntarily  or by
       operation of law, assign,  transfer,  mortgage,  pledge, or encumber this
       Lease or any interest therein,  and shall not sublet the said Premises or
       any part  thereof,  or any right or  privilege  appurtenant  thereto,  or
       suffer any other person (the employees,  agents, servants and invitees of
       Tenant  excepted)  to  occupy  or use the said  Premises  or any  portion
       thereof,  without  written  consent of Landlord  first had and  obtained,
       which consent shall not be unreasonably withheld;  provided however, that
       Landlord in the exercise of its good faith  business  judgment may refuse
       to approve the assignment or sublease and shall  promptly  provide Tenant
       with the reasons for its refusal.  In the event Tenant  desires to assign
       this Lease or any interest therein or sublet all or part of the Premises,
       Tenant shall give Landlord  written  notice  thereof,  which notice shall
       include  (i) the name of the  proposed  assignee,  subtenant  or occupant
       ("Transferee"),  (ii)  reasonable  financial  information  regarding  the
       Transferee,  (iii)  a  description  of the  Transferee's  business  to be
       carried  on in the  Premises,  and (iv) the  terms of the  assignment  or
       sublease and a description of the portion of the Premises to be affected.
       Tenant shall also provide Landlord such additional  information regarding
       the  Transferee  or the proposed  assignment  or sublease as Landlord may
       reasonably request.

       Notwithstanding  the foregoing,  Tenant shall have the right to assign or
       sublet the premises,  or a portion thereof,  to a wholly owned affiliated
       company or subsidiary,  without the

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       Landlord's  consent.  Tenant shall be required,  however, to give written
       notice to Landlord in advance of such assignment or sublet and to prepare
       assignment or sublet agreements on forms that are reasonably satisfactory
       to  Landlord.  In no event  shall such an  assignment  or sublet  release
       Tenant from its obligations under the terms of this Lease.

       Consent to one  assignment,  subletting,  occupation  or use by any other
       person  shall not be deemed to a consent  to any  subsequent  assignment,
       subletting,  occupation  or use by  another  person.  Any  assignment  or
       subletting  without such consent shall be void, and shall,  at the option
       of the Landlord, constitute a default under this Lease.

14.    HOLD HARMLESS Tenant shall indemnify and hold harmless  Landlord  against
       and from any and all claims arising from Tenant's use of Premises for the
       conduct of its business or from any  activity,  work or other thing done,
       permitted or suffered by the Tenant in or about the  Building,  and shall
       further indemnify and hold harmless Landlord against and from any and all
       claims  arising  from any  breach or default  in the  performance  of any
       obligation  on  Tenant's  part to be  performed  under  the terms of this
       Lease,  or  arising  from any act or  negligence  of the  tenant,  or any
       officer,  agent,  employee,  guest or  invitee  of  Tenant,  and from and
       against all cost,  attorney's fees, expenses and liabilities  incurred in
       or about any such claim or any action or proceeding  brought  thereon and
       in any case,  action or proceeding  brought against Landlord by reason of
       any such claim. Tenant upon notice from Landlord shall defend the same at
       Tenant's expense by counsel reasonably  satisfactory to Landlord.  Tenant
       as a material part of the  consideration  to Landlord  hereby assumes all
       risk of damage to property  or injury to  persons,  in, upon or about the
       Premises, from any cause other than Landlord's negligence or willful act,
       and Tenant hereby waives all claims in respect thereof against Landlord.

       Landlord  or its agents  shall not be liable  for any damage to  property
       entrusted  to employees  of the  Building,  nor for loss or damage to any
       property  by theft or  otherwise,  nor for any  injury  to or  damage  to
       persons or property  resulting  from fire,  explosion,  falling  plaster,
       steam,  gas,  electricity,  water or rain which may leak  dampness or any
       other cause  whatsoever,  unless  caused by or due to the  negligence  or
       willful acts of Landlord, its agents,  servant or employees.  Landlord or
       its agents shall not be liable for  interference  with the light or other
       incorporeal hereditaments, less of business by Tenant, nor shall Landlord
       be liable  for any  latent  defect in the  premises  or in the  Building.
       Tenant shall give prompt  notice to Landlord in case of fire or accidents
       in the  Premises  or in the  Building  or of  defects  therein  or in the
       fixtures or equipment.

15.    SUBROGATION  Landlord and Tenant hereby  mutually waive their  respective
       rights of  recovery  against  each  other for any loss  insured  by fire,
       extended coverage and other property  insurance policies existing for the
       benefit of the  respective  parties.  Each party shall obtain any special
       endorsements,  if required by their insurer to evidence  compliance  with
       the aforementioned waiver.

16.    LIABILITY INSURANCE Tenant shall, at Tenant's expense, obtain and keep in
       force  during  the  term of this  Lease,  (1) a policy  of  comprehensive
       general  liability  insurance  insuring  Landlord and Tenant  against any
       liability arising out of the ownership,  use, occupancy or maintenance of
       the Premises and all areas appurtenant thereto; (2) workers' compensation
       insurance  as may be  required  by  law;  and  (3)  "all  risk"  property
       insurance on Tenant's  above-standard  tenant improvements  (specifically
       those improvements  exceeding the Landlord's tenant improvement allowance
       as defined in Addendum to Lease,  P.4.B),  personal property,  equipment,
       furniture and fixtures.  The limit of said insurance shall not,

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       however,  limit the liability of the Tenant  hereunder.  Tenant may carry
       said insurance under a blanket policy, providing, however, said insurance
       by  Tenant  shall  have a  Landlord's  protective  liability  endorsement
       attached  thereto.  If Tenant  shall fail to procure  and  maintain  said
       insurance,  Landlord  may,  but shall not be  required  to,  procure  and
       maintain  same,  but  at  the  expense  of  Tenant.   Insurance  required
       hereunder,  shall be in  companies  rated  A+ AAA or  better  in  "Best's
       Insurance  Guide." Tenant shall deliver to Landlord prior to occupancy of
       the Premises copies of policies of liability insurance required herein or
       certificates  evidencing the existence and amounts of such insurance with
       loss payable clauses reasonably satisfactory to Landlord. No policy shall
       be cancelable  or subject to reduction of coverage  except after ten (10)
       days prior written notice to Landlord.

17.    See Addendum to Lease, P. 7, Services and Utilities.

18.    PROPERTY TAXES Tenant shall pay, or cause to be paid, before delinquency,
       any and all taxes levied or assessed and which become  payable during the
       term  hereof  upon  all  Tenant's  leasehold   improvements,   equipment,
       furniture, fixtures and personal property located in the Premises; except
       that  which has been paid for by  Landlord,  and is the  standard  of the
       Building. In the event any or all of the Tenant's leasehold improvements,
       equipment,  furniture,  fixtures and personal  property shall be assessed
       and taxed with the  Building,  Tenant  shall pay to Landlord its share of
       such taxes within ten (10) days after delivery to Tenant by Landlord of a
       statement in writing setting forth the amount of such taxes applicable to
       Tenant's property.

19.    RULES AND REGULATIONS Tenant shall faithfully observe and comply with the
       reasonable  rules and  regulations  that Landlord shall from time to time
       promulgate.  Landlord  reserves  the right  from time to time to make all
       reasonable  modifications to said rules. The additions and  modifications
       to those  rules shall be binding  upon Tenant upon  delivery of a copy of
       them to Tenant.  Landlord shall not be responsible for the nonperformance
       of any said  rules by any  other  tenants  or  occupants.  The  rules and
       regulations  shall be applied  equally to all tenants  occupying  Regency
       Center.

20.    HOLDING OVER If Tenant  remains in possession of the Premises or any part
       thereof after the expiration of the term hereof, with the express written
       consent  of   Landlord,   such   occupancy   shall  be  a  tenancy   from
       month-to-month at a rental in the amount of the last monthly rental, plus
       all  other  charges  payable  hereunder,  and upon all the  terms  hereof
       applicable to a month-to-month tenancy.

21.    ENTRY BY LANDLORD  Landlord  reserves and shall at any and all times have
       the right to enter the  Premises,  inspect  the same,  supply  janitorial
       service  and any other  service  to be  provided  by  Landlord  to Tenant
       hereunder,  to submit said Premises to prospective purchasers or tenants,
       to post notices of  non-responsibility,  and to alter,  improve or repair
       the  Premises and any portion of the Building of which the Premises are a
       part that Landlord may deem necessary or desirable,  without abatement of
       rent and may for that  purpose  erect  scaffolding  and  other  necessary
       structures where  reasonably  required by the character of the work to be
       performed,  always  providing that the entrance to the Premises shall not
       be blocked thereby, and further providing that the business of the Tenant
       shall not be interfered with unreasonably. Tenant hereby waives any claim
       for damages or for any injury or  inconvenience  to or interference  with
       Tenant's  business  any  loss of  occupancy  or  quiet  enjoyment  of the
       Premises,  and  any  other  loss  occasioned  thereby.  For  each  of the
       aforesaid  purposes,  Landlord  shall at all times  have and retain a key
       with  which to unlock all of the doors in,  upon and about the  Premises,
       excluding  Tenant's  vaults,  safes and  files,

                                       7
<PAGE>

       and specific,  secured,  sensitive and confidential  offices and Landlord
       shall  have the right to use any and all means  which  Landlord  may deem
       proper to open said doors in any  emergency,  in order to obtain entry to
       the  Premises  without  liability  to Tenant  except  for any  failure to
       exercise  due care  for  Tenant's  property.  Any  entry to the  Premises
       obtained by Landlord by any of said means,  or otherwise  shall not under
       any  circumstances  be  construed  or deemed to be a forcible or unlawful
       entry into, or a detainer of, the Premises, or an eviction of Tenant from
       the Premises or any portion thereof.

22.    RECONSTRUCTION  In the event the  Premises  or the  Building of which the
       Premises  are a part are  damaged  by fire or  other  perils  covered  by
       extended  coverage  insurance,  Landlord  agrees to forthwith  repair the
       same,  and this Lease shall remain in full force and effect,  except that
       Tenant shall be entitled to a  proportionate  reduction of the rent while
       such  repairs are being made,  such  proportionate  reduction to be based
       upon the  extent to which the  making of such  repairs  shall  materially
       interfere with the business carried on by the Tenant in the Premises.  If
       the  damage is due to the fault or  neglect  of Tenant or its  employees,
       there shall be no abatement of rent.

       In the event the  Premises or the  Building of which the  Premises  are a
       part are damaged as a result of any cause  other than the perils  covered
       by fire or extended  coverage  insurance,  then Landlord shall  forthwith
       repair the same provided the extent of the  destruction  be less than ten
       (10%) of the then full  replacement  cost of the Premises or the Building
       of which the Premises  are a part.  In the event the  destruction  of the
       Premises or the  Building is to an extent  greater  than ten (10%) of the
       full replacement  cost, then Landlord shall have the option (1) to repair
       or restore such damage,  this Lease  continuing in full force and effect,
       but the rent to be proportionately reduced as hereinabove in this Article
       provided; or (2) give notice to Tenant at any time within sixty (60) days
       after such damage terminating this Lease as of the date specified in such
       notice,  which  date shall be no less than  thirty  (30) and no more than
       sixty (60) days after the giving of such  notice.  In the event of giving
       such  notice,  this Lease shall  expire and all interest of the Tenant in
       the Premises shall  terminate on the date so specified in such notice and
       the Rent,  reduced by a proportionate  amount,  based upon the extent, if
       any, to which such damage materially interfered with the business carried
       on by the Tenant in the  Premises,  shall be paid up to date of said such
       termination.

       Notwithstanding  anything  to the  contrary  contained  in this  Article,
       Landlord shall not have any obligation whatsoever to repair,  reconstruct
       or restore the damage to the Premises resulting from any casualty covered
       under this Article which occurs during the last twelve (12) months of the
       term of this Lease or any extension thereof.

       Landlord  shall not be required to repair any injury or damage by fire or
       other cause, or to make any repairs to replacements of any  over-standard
       tenant  improvements  (specifically  those  exceeding  Landlord's  tenant
       improvement allowance as defined in Addendum to Lease, P.4.B) or Tenant's
       trade fixtures, equipment, furniture or personal property.

       Except for abatement of rent as provided  above,  the Tenant shall not be
       entitled to any compensation or damages from Landlord for loss of the use
       of the whole or any part of the premises,  Tenant's  personal property or
       any  inconvenience  or  annoyance  occasioned  by  such  damage,  repair,
       reconstruction or restoration.

23.    DEFAULT  The  occurrence  of any or more of the  following  events  shall
       constitute a default and breach of this Lease by Tenant:

                                       8
<PAGE>

       A.    The vacating or  abandonment  of the Premises by Tenant,  except in
             cases when Tenant is current with all rental payments.

       B.    The  failure  by  Tenant to make any  payment  of rent or any other
             payment required to be made by Tenant  hereunder,  as and when due,
             where such  failure  shall  continue  for a period of ten (10) days
             after written notice thereof by Landlord to Tenant.

       C.    The failure by Tenant to observe or perform  any of the  covenants,
             conditions  or provisions of this Lease to be observed or performed
             by the Tenant,  other than described in Article 23.B. above,  where
             such failure shall  continue for a period of thirty (30) days after
             written  notice thereof by Landlord to Tenant;  provided,  however,
             that if the  nature  of  Tenant's  default  is such  that more than
             thirty (30) days are reasonably  required for its cure, then Tenant
             shall not be deemed to be in default if Tenant  commences such cure
             within  said  thirty  (30) day  period  and  thereafter  diligently
             prosecutes such cure to completion.

       D.    The  making  by  Tenant  of  any  general   assignment  or  general
             arrangement  for the  benefit  of  creditors,  or the  filing by or
             against Tenant of a petition to have Tenant adjudged a bankrupt, or
             a petition or  reorganization or arrangement under any law relating
             to  bankruptcy  (unless,  in the case of a petition  filed  against
             Tenant,  the same is  dismissed  within  sixty (60)  days);  or the
             appointment  of a  trustee  or a  receiver  to take  possession  of
             substantially  all of Tenant's assets located at the Premises or of
             Tenant's  interest in this Lease,  where possession is not restored
             to Tenant within thirty (30) days; or the attachment,  execution or
             other  judicial  seizure of  substantially  all of Tenant's  assets
             located at the  Premises  or of Tenant's  interests  in this Lease,
             where such seizure is not discharged in thirty (30) days.

24.    REMEDIES IN DEFAULT In the event of any such  material  default or breach
       by Tenant, Landlord may at any time thereafter, with or without notice or
       demand and without limiting Landlord in the exercise of a right or remedy
       which Landlord may have by reason of such default or breach:

       A.    Terminate  Tenant's  right to  possession  of the  Premises  by any
             lawful means,  in which case this Lease shall  terminate and Tenant
             shall immediately surrender possession of the Premises to Landlord.
             In such event Landlord shall be entitled to recover from Tenant all
             damages  incurred by necessary  renovation  and  alteration  of the
             Premises,  reasonable  attorney's fees, any real estate  commission
             actually  paid,  the worth at the time of award by the court having
             jurisdiction thereof of the amount by which the unpaid rent for the
             balance of the term after the time of such award exceeds the amount
             of such rental loss for the same period that Tenant proves could be
             reasonably avoided,  that portion of the leasing commission paid by
             Landlord and applicable to the unexpired term of this Lease. Unpaid
             installments  of rent or other sums shall  bear  interest  from the
             date due at the rate of ten (10%)  percent per annum.  In the event
             Tenant shall have  abandoned the Premises,  Landlord shall have the
             option of (a) taking possession of the Premises and recovering from
             Tenant the amount  specified in this  paragraph,  or (b) proceeding
             under the provisions of the following Article 24.B.

       B.    Maintain  Tenant's  right to  possession,  in which case this Lease
             shall continue in effect whether or not Tenant shall have abandoned
             the Premises.  In such event  Landlord shall be entitled to enforce
             all of Landlord's  right and remedies  under this Lease,  including
             the right to recover the rent as it becomes due hereunder.

                                       9
<PAGE>

       C.    Pursue any other  remedy now or  hereafter  available  to  Landlord
             under  the laws or  judicial  decision  of the  State in which  the
             Premises are located.

25.    EMINENT  DOMAIN If more than  twenty-five  (25%)  percent of the Premises
       shall be taken or appropriated  by any public or  quasi-public  authority
       under the power of eminent  domain,  either  party  hereto shall have the
       right,  at its option,  to terminate  this Lease,  and Landlord  shall be
       entitled  to any and all  income,  rent,  award or any  interest  therein
       whatsoever  which may be paid or made in  connection  with such public or
       quasi-public  use or  purpose,  and Tenant  shall  have no claim  against
       Landlord  for the value of any  unexpired  term of this Lease.  If either
       less than or more than  twenty-five  (25%)  percent  of the  Premises  is
       taken,  and neither  party elects to terminate  as herein  provided,  the
       rental thereafter to be paid shall be equitably  reduced.  If any part of
       the Building  other than the  Premises  may be so taken or  appropriated,
       Landlord  shall have the right at its option to terminate  this Lease and
       shall be entitled to the entire award as above provided.  Notwithstanding
       the  foregoing,   Tenant  shall  be  entitled  to  that  portion  of  any
       condemnation  award made  specifically on account of Tenant's  relocation
       expenses,  increased  rental costs,  improvements  contracted at Tenant's
       expense or disruption of Tenant's business.

26.    OFFSET  STATEMENT Tenant shall at any time and from time to time upon not
       less than ten (10) days  prior  written  notice  from  Landlord  execute,
       acknowledge and deliver to Landlord a statement in writing (a) certifying
       that this  Lease is  unmodified  and in full  force and  effect  (or,  if
       modified,  stating the nature of such  modification  and certifying  that
       this Lease as so  modified  is in full force and  effect) and the date to
       which the rental and other  charges are paid in advance,  if any, and (b)
       acknowledging  that there are not,  to  Tenant's  knowledge,  any uncured
       defaults  on the  part  of the  Landlord  hereunder  or  specifying  such
       defaults if any are claimed. Any such statement may be relied upon by any
       prospective  purchaser or  encumbrancer of all or any portion of the real
       property of which the Premises are a part.

27.    PARKING  Tenant shall have the right to use in common with other  tenants
       or occupants of the Building the parking facilities of the Building.

28.    AUTHORITY OF PARTIES

       A.    Corporate  Authority.  If Tenant is a corporation,  each individual
             executing this Lease on behalf of said  corporation  represents and
             warrants  that he is duly  authorized  to execute and deliver  this
             Lease on  behalf of said  corporation,  in  accordance  with a duly
             adopted resolution of the board of directors of said corporation or
             in accordance with the by-laws of said  corporation,  and that this
             Lease is  binding  upon said  corporation  in  accordance  with its
             terms.

       B.    Limited   Partnerships.   If  the  Landlord  herein  is  a  limited
             partnership,  it is understood and agreed that any claims by Tenant
             on  Landlord  shall  be  limited  to  the  assets  of  the  limited
             partnership,  and furthermore,  Tenant expressly waives any and all
             rights to proceed against the individual  partners or the officers,
             directors or shareholders of any corporate  partner,  except to the
             extent of their interest in said limited partnership.

                                       10
<PAGE>

29.    GENERAL PROVISIONS

       (i)   Plats and Riders.  Clauses, plats and riders, if any, signed by the
             Landlord  and the Tenant and  endorsed  on or affixed to this Lease
             are a part hereof.

       (ii)  Waiver.  The waiver by Landlord of any term,  covenant or condition
             herein  contained  shall not be deemed to be a waiver of such term,
             covenant or condition on any  subsequent  breach of the same or any
             other term, covenant or condition herein contained.  The subsequent
             acceptances of rent hereunder by Landlord shall not be deemed to be
             a waiver of any preceding breach by Tenant of any term, covenant or
             condition  of this  Lease,  other than the failure of the Tenant to
             pay the  particular  rental so accepted,  regardless  of Landlord's
             knowledge of such preceding breach at the time of the acceptance of
             such rent.

       (iii) Notices. All notices and demands which may or are to be required or
             permitted to be given by either party to the other  hereunder shall
             be in  writing.  All  notices  and  demands by the  Landlord to the
             Tenant  shall  be sent by  United  States  Mail,  postage  prepaid,
             addressed  to the Tenant at 120 North  Redwood  Drive,  San Rafael,
             California  94903,  or to such other places as Tenant may from time
             to time  designate  in a notice to the  Landlord.  All  notices and
             demands  by the  Tenant  to the  Landlord  shall be sent by  United
             States  Mail,  postage  prepaid,  addressed  to the Landlord at 100
             Smith Ranch Road,  Suite 325, San Rafael,  California  94903, or to
             such other  person or place as the  Landlord  may from time to time
             designate in a notice to the Tenant.

       (iv)  Joint Obligation.  If there be more than one Tenant the obligations
             hereunder imposed upon Tenants shall be joint and several.

       (v)   Marginal Headings. The marginal headings and titles to the Articles
             of this Lease are not a part of this Lease and shall have no effect
             upon the construction or interpretation of any part hereof.

       (vi)  Time.  Time is of the essence of this Lease and each and all of its
             provisions in which performance is a factor.

       (vii) Successors  and  Assigns.   The  covenants  and  conditions  herein
             contained, subject to the provisions as to assignment, apply to and
             bind the heirs, successors,  executors,  administrators and assigns
             of the parties hereto.

       (viii)Recordation.  Neither  Landlord  nor Tenant shall record this Lease
             or a short form memorandum hereof without the prior written consent
             of the other party.

       (ix)  Quiet  Possession.  Upon Tenant paying the rent reserved  hereunder
             and observing and performing  all of the covenants,  conditions and
             provisions on Tenant's part to be observed and performed hereunder,
             Tenant shall have quiet  possession  of the Premises for the entire
             term hereof, subject to all the provisions of this Lease.

       (x)   Late  Charges.  Tenant  hereby  acknowledges  that late  payment by
             Tenant to Landlord of rent or other sums due  hereunder  will cause
             Landlord to incur costs not  contemplated by this Lease,  the exact
             amount of which will be  extremely  difficult  to  ascertain.  Such
             costs  include,  but are not limited to,  processing and accounting

                                       11
<PAGE>

             charges,  and late charges  which may be imposed  upon  Landlord by
             terms  of  any  mortgage  or  trust  deed  covering  the  Premises.
             Accordingly, if any installment of rent or of a sum due from Tenant
             shall not be received by Landlord or Landlord's designee within ten
             (10) days after said amount is past due,  then Tenant  shall pay to
             Landlord a late charge  equal to ten (10%)  percent of such overdue
             amount. The parties hereby agree that such late charges represent a
             fair and  reasonable  estimate of the cost that Landlord will incur
             by reason of the late  payment by Tenant.  Acceptance  of such late
             charges  by  Landlord  shall in no  event  constitute  a waiver  of
             Tenant's  default with respect to such overdue amount,  nor prevent
             Landlord  from  exercising  any of the other  rights  and  remedies
             granted hereunder.

       (xi)  Prior Agreements.  This Lease contains all of the agreements of the
             parties  hereto with respect to any matter  covered or mentioned in
             this Lease, and no prior agreements or understanding  pertaining to
             any such matters shall be effective  for any purpose.  No provision
             of this Lease may be amended or added to except by an  agreement in
             writing signed by the parties hereto or their respective successors
             in  interest.  This Lease shall not be  effective or binding on any
             party until fully executed by both parties hereto.

       (xii) Inability to Perform.  This Lease and the obligations of the Tenant
             hereunder shall not be affected or impaired because the Landlord is
             unable to fulfill any of its obligations hereunder or is delayed in
             doing so, if such inability or delay is caused by reason of strike,
             labor  troubles,  acts  of  God,  or any  other  cause  beyond  the
             reasonable control of the Landlord.

       (xiii)Attorney's  Fees. In the event of any action or proceeding  brought
             by either party  against the other under this Lease the  prevailing
             party shall be entitled to recover all costs and expenses including
             the fees of its  attorneys  in such  action or  proceeding  in such
             amount as the court may adjudge reasonable as attorney's fees.

       (xiv) Sale of  Premises  by  Landlord.  In the  event  of any sale of the
             Building,  Landlord  shall  be and is  hereby  entirely  freed  and
             relieved of all  liability  under any and all of its  covenants and
             obligations  contained in or derived from this Lease arising out of
             any act, occurrence or omission occurring after the consummation of
             such sale; and the purchaser,  at such sale or any subsequent  sale
             of the  Premises  shall be deemed,  without any  further  agreement
             between the parties or their  successors in interest or between the
             parties and any such  purchaser to have assumed and agreed to carry
             out any and all of the  covenants and  obligations  of the Landlord
             under this Lease.

       (xv)  Subordination Attornment. Upon request of the Landlord, Tenant will
             in  writing  subordinate  its rights  hereunder  to the lien of any
             first  mortgage,  or first  deed of trust  to any  bank,  insurance
             company or other  lending  institution,  now or  hereafter in force
             against the land and Building of which the Premises are a part, and
             upon any  buildings  hereafter  placed  upon the land of which  the
             Premises are a part,  and to all  advances  made or hereafter to be
             made upon the security thereof.

             Notwithstanding such subordination, neither Tenant's right to quiet
             possession  of the  Premises  nor this Lease shall be  disturbed or
             affected  if  Tenant  is not in  default  hereunder  and so long as
             Tenant  shall  pay the  rent and  observe  and

                                       12
<PAGE>

             perform all of the  provisions of this Lease,  unless this Lease is
             otherwise terminated pursuant to its terms.

       (xvi) In the event any proceedings are brought for foreclosure, or in the
             event of the  exercise of power of sale under any  mortgage or deed
             of trust made by the  Landlord  covering the  Premises,  the Tenant
             shall attorn to the purchaser upon any such foreclosure or sale and
             recognize such purchaser as the Landlord under this Lease.

       (xvii)Name.  Tenant  shall  not use the  name of the  Building  or of the
             development in which the Building is situated for any purpose other
             than as an address of the business to be conducted by the Tenant in
             the Premises.

       (xviii) Separability. Any provision of this Lease which shall prove to be
             invalid,  void  or  illegal  shall  in no  way  effect,  impair  or
             invalidate  any other  provision  hereof and such  other  provision
             shall remain in full force and effect.

       (xix) Cumulative  Remedies.  No remedy  or  election  hereunder  shall be
             deemed exclusive but shall,  wherever possible,  be cumulative with
             all other remedies at law or in equity.

       (xx)  Choice of Law.  This  Lease  shall be  governed  by the laws of the
             State in which the Premises are located.

       (xxi) Signs  and  Auctions.  Tenant  shall  not  place  any sign upon the
             Premises  or  Building  or  conduct  any  auction  thereon  without
             Landlord's prior written consent.

30.    BROKERS Tenant  warrants that it has had no dealings with any real estate
       broker or agents in connection  with the negotiation of this Lease and it
       knows no real estate  broker or agent who is entitled to a commission  in
       connection with this Lease.


                The Joseph and Eda Pell                 Fair, Isaac and Company,
                    Revocable Trust                           Incorporated



       By:  Joseph Pell                   By:  Robert D. Sanderson
            -----------------------------      ---------------------------------
                      Joseph Pell


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



       By:  Eda Pell                      Date:  December 28, 1993
            -----------------------------      ---------------------------------
                       Eda Pell


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


       Date:  January 14, 1994
            -----------------------------

                                       13
<PAGE>

                              RULES AND REGULATIONS

   1.  No  sign,  placard,  picture,  advertisement,  name or  placard  shall be
       inscribed,  displayed  or  printed  or  affixed  on or to any part of the
       outside or inside of the  Building  without  the  written  consent of the
       Landlord  first had and  obtained  and  Landlord  shall have the right to
       remove any such sign,  placard,  picture,  advertisement,  name or notice
       without notice to and at the expense of Tenant.

       All  approved  signs or  lettering  on doors shall be  printed,  painted,
       affixed or inscribed at the expense of Tenant by a person  approved of by
       Landlord.

       Tenant shall not place  anything or allow  anything to be placed near the
       glass of any window,  door,  partition or wall which may appear unsightly
       from outside the Premises;  provided,  however, that Landlord may furnish
       and install a Building  standard window covering at all exterior windows.
       Tenant  shall not without  prior  written  consent of  Landlord  cause or
       otherwise sunscreen any window.

   2.  The sidewalks, halls, passages, exits, entrances, elevators and stairways
       shall not be  obstructed  by any of the  tenants  or used by them for any
       purpose other than for ingress and egress from their respective Premises.

   3.  Tenant  shall not alter any lock or install any new or  additional  locks
       without  permission of Landlord,  whose consent shall not be unreasonably
       withheld, or any bolts on any doors or windows of the Premises.

   4.  The toilet rooms,  urinals,  wash bowls and other  apparatus shall not be
       used for any purpose other than that for which they were  constructed and
       no foreign  substance of any kind whatsoever  shall be thrown therein and
       the  expense  of  any  breakage,  stoppage,  damage  resulting  from  the
       violation  of this  rule  shall  be  borne by the  Tenant  who,  or whose
       employees or invitees shall have caused it.

   5.  Tenant  shall not overload the floor of the Premises or in any way deface
       the Premises or any part thereof.

   6.  No furniture,  freight or equipment of any kind shall be brought into the
       Building  without the prior notice to Landlord and all moving of the same
       into or out of the Building shall be done at such time and in such manner
       as Landlord shall designate. Notwithstanding the above, Tenant shall have
       the right to move  furniture,  freight or  equipment  into and out of the
       building  without  prior notice to Landlord,  provided that such moves do
       not involve  exclusive use of an elevator for an extended period of time,
       nor does the move  interfere  with the  operation of other tenants in the
       building. Landlord shall have the right to prescribe the weight, size and
       position of all safes and other heavy equipment brought into the Building
       and  also the  times  and  manner  of  moving  the same in and out of the
       Building.  Safes or other heavy objects shall, if considered necessary by
       Landlord, stand on supports of such thickness as is necessary to properly
       distribute the weight.  Landlord will not be  responsible  for loss of or
       damage to any such safe or property from any cause and all damage done to
       the  Building by moving or  maintaining  any such safe or other  property
       shall be repaired at the expense of the Tenant.

                                        2
<PAGE>

   7.  Tenant  shall  not  use,  keep or  permit  to be used or kept any foul or
       noxious  gas or  substance  in the  Premises,  or permit  or  suffer  the
       Premises to be occupied or used in a manner offensive or objectionable to
       the Landlord or other occupants of the Building by reason of noise, odors
       and/or  vibrations,  or interfere in any way with other  tenants or those
       having business therein,  nor shall any animals or birds be brought in or
       kept in or about the Premises or the Building.

   8.  No cooking,  except for microwave and coffee  machines,  shall be done or
       permitted by any Tenant on the  Premises,  nor shall the Premises be used
       for the storage of merchandise,  for washing clothes, for lodging, or for
       any improper, objectionable or immoral purposes.

   9.  Tenant  shall  not  use or  keep  in the  Premises  of the  Building  any
       kerosene,  gasoline or inflammable or combustible  fluid or material,  or
       use any method of heating or air conditioning other than that supplied by
       Landlord.

  10.  Landlord  will  direct  electricians  as to where and how  telephone  and
       telegraph wires are to be introduced. No boring or cutting for wires will
       be  allowed  without  the  consent  of  the  Landlord.  The  location  of
       telephones, call boxes and other office equipment affixed to the Premises
       shall  be  subject  to the  approval  of  Landlord,  which  shall  not be
       unreasonably withheld.

  11.  On Saturdays,  Sundays and legal holidays,  and on other days between the
       hours of 6:00  P.m.  and 8:00  a.m.  the  following  day,  access  to the
       Building,  or to the halls,  corridors,  elevators  or  stairways  in the
       Building,  or to the  Premises may be refused  unless the person  seeking
       access is known to the person or employee  of the  Building in charge and
       has a pass or is properly  identified.  The Landlord  shall in no case be
       liable for  damages  for any error  with  regard to the  admission  to or
       exclusion  from the  Building of any person.  In case of  invasion,  mob,
       riot, public  excitement,  or other commotion,  the Landlord reserves the
       right to prevent  access to the Building  during the  continuance  of the
       same by closing of the doors or otherwise,  for the safety of the tenants
       and protection of property in the Building and the Building.

  12.  Landlord  reserves  the right to exclude or expel from the  Building  any
       person who, in the  judgment of  Landlord,  is  intoxicated  or under the
       influence  of liquor or drugs,  or who shall in any  manner do any act in
       violation of any of the rules and regulations of the Building.

  13.  No vending  machine or machines of any  description  shall be  installed,
       maintained or operated upon the Premises  without the written  consent of
       the Landlord, which shall not be unreasonably withheld.

  14.  Landlord  shall have the right,  exercisable  without  notice and without
       liability  to  Tenant,  to  change  the name and  street  address  of the
       Building of which the Premises are a part.

  15.  Tenant  shall not  disturb,  solicit,  or  canvass  any  occupant  of the
       Building and shall cooperate to prevent same.

  16.  Without the written consent of Landlord, Tenant shall not use the name of
       the  Building in  connection  with or in  promoting  or  advertising  the
       business of Tenant except as Tenant's address.

                                       3
<PAGE>

  17.  Landlord shall have the right to control and operate the public  portions
       of  the  Building,  and  the  public  facilities,  and  heating  and  air
       conditioning,  as well as facilities  furnished for the common use of the
       tenants,  in such  manner as it deems best for the benefit of the tenants
       generally.

  18.  All entrance doors in the Premises shall be left locked when the Premises
       are not in use, and all doors opening to public  corridors  shall be kept
       closed  except for normal  ingress and egress from the  Premises,  unless
       suite entry doors are controlled by UL and municipally approved hold-open
       devices which are connected to building life-safety systems.


                                       4
<PAGE>
                             FIRST ADDENDUM TO LEASE
                                 BY AND BETWEEN
                 THE JOSEPH & EDA PELL REVOCABLE TRUST, LANDLORD
                                       AND
                  FAIR, ISAAC AND COMPANY, INCORPORATED, TENANT
                             DATED OCTOBER 11, 1993



1.     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.

2.     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;

                                       1
<PAGE>

               (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 P.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.

                                       2
<PAGE>

3.     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 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 who wish to renew their respective
       leases,  and that these existing options and requests to renew would take
       precedent over the 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 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 30 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 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.

4.     TENANT IMPROVEMENTS

       A.    Construction:  Landlord shall,  prior to the Commencement  Date (as
             defined in Addendum  P.6.A),  construct the tenant  improvements in
             Tenant's  Premises  based on the space plan  prepared  by  Tenant's
             Architect  dated  _______,  Exhibit  B to the  Lease,  and  working
             drawings prepared by ______________,  dated ___________, which will
             be attached to the Lease as Exhibit C.

                                       3
<PAGE>

       B.    Allowance:  Landlord shall  contribute  Eighty Thousand Six Hundred
             Thirty-eight  Dollars ($80,638.00) ($23.00 x 3,506 useable sq. ft.)
             toward the  construction  of the tenant  improvements  for Tenant's
             Premises.  The  Tenant  Improvement  Allowance  shall  include  all
             architectural,  engineering and consultant  fees. In the event that
             the total cost of the tenant improvements including  architectural,
             engineering  and consulting  fees,  exceeds the Tenant  Improvement
             Allowance,  Tenant  shall pay  Landlord  the amount of such  excess
             within  thirty (30) days after receipt by Tenant of an invoice from
             Landlord  documenting the cost of the tenant  improvement  work. In
             the event the total cost of the  tenant  improvements  in  Tenant's
             Premises is less than  $80,638.00,  Landlord  shall provide  Tenant
             with a credit for the unused  balance which Tenant can apply to the
             Tenant Improvement Allowance for the build-out in Tenant's Premises
             on the  Second  Floor of the  Building  (See  Lease  dated July 10,
             1993).

       C.    Contractor:  The contractor for the tenant improvements in Tenant's
             Premises  shall be Mike  Donovan.  Tenant shall  approve the budget
             figures for the build-out prior to commencement of the work.

             If Tenant chooses, WBE Electrical and WBE Telecom shall provide the
             electrical and data communication system cabling services, Peerless
             Lighting will provide lighting fixtures,  and Warren Security shall
             provide the security systems.

       D.    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  working
             drawings, 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.

       E.    Substantial  Completion:  For purposes of this Lease,  "Substantial
             Completion" shall mean that construction of the tenant improvements
             has been completed in accordance with the working drawings,  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 seven calendar (7) days after Substantial  Completion of the
             tenant  improvements,  Tenant  shall  make  an  inspection  of  the
             Premises and prepare a punchlist of items needing  additional  work
             by  the  Contractor.   Landlord's  Contractor  shall  complete  all
             punchlist items reasonably  identified by Tenant or Landlord within
             thirty  calendar  (30)  days  after  the  inspection  or as soon as

                                       4
<PAGE>

             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.

             Landlord's  Contractor will perform the tenant improvement work and
             Landlord   will  notify   Tenant  in  writing   that  the  work  is
             Substantially Complete. If Tenant fails to object in writing within
             seven calendar (7) days thereafter  specifying in reasonable detail
             the  items of work  needed  to be  performed  in  order to  achieve
             Substantial Completion, then Tenant shall be deemed conclusively to
             have agreed that the work is Substantially  Complete,  for purposes
             of Commencement under the Lease.  Substantial  Completion shall not
             prejudice  Tenant's  rights  to  require  full  completion  of  any
             remaining items of work.

       F.    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.
             All trade  fixtures,  equipment,  furniture  and personal  property
             installed  by or at the expense of Tenant shall remain the property
             of Tenant.

       G.    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.

5.     POSSESSION

       A.    If for any reason whatsoever, Landlord cannot deliver possession of
             the  Premises to Tenant as of the  Commencement  Date as defined in
             Addendum,  P.6.A,  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 above term be in
             any way  extended,  but in that  event,  all rent  shall be  abated
             during the period between the  Commencement  Date and the date when
             Landlord actually delivers possession.

       B.    In the event  Landlord  shall permit  Tenant to occupy the Premises
             prior to the Commencement  Date, such occupancy shall be subject to
             all of the provisions of this Lease.  Said early  possession  shall
             not advance the termination date hereinabove provided.

       C.    If Landlord  shall not have  delivered  possession  of the Premises
             within ninety (90) days after the Commencement  Date (as defined in
             Addendum  P.6.),  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. If there are Tenant
             Caused Delays (as defined in Addendum  P.6.C.),  the number of days
             of

                                       5
<PAGE>

             delay shall be added to the ninety (90) days in which  Landlord has
             to deliver  possession of the Premises  before Tenant has the right
             to cancel this Lease.

6.     COMMENCEMENT

       A.    The  Commencement  Date shall be defined as five (5) business  days
             after Landlord delivers possession of the Premises to Tenant, after
             Substantial  Completion of the tenant  improvement work (as defined
             in  Addendum  P.4.E) and in no event  later  than  January 5, 1994.
             Thirty  (30) days  after  Substantial  Completion,  Landlord  shall
             notify  Tenant in writing of the actual  Commencement  Date. In the
             event Substantial Completion is delayed by Tenant Caused Delays (as
             defined  in  Addendum  P.6.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 Date.

       B.    The following  shall be deemed  "Tenant Caused Delays" for purposes
             of this lease:

               (i)     Tenant's  or  Tenant's   Architect's  failure  to  timely
                       complete,  approve or  reasonably  object to any proposed
                       plans,  specifications  or drawings for the Premises,  or
                       the tenant improvement work.

               (ii)    Tenant's  requests for changes,  alterations or additions
                       with respect to the layout of the Premises, the build-out
                       of the tenant improvements and the materials or finish of
                       the improvements which result in delay.

               (iii)   Any  upgrades,  special  work,  fixtures or  equipment or
                       other  items to the extent that the same  involve  longer
                       lead  times,  installation  times  or  other  delays  not
                       encountered  in  standard  office  improvements  or  as a
                       result  of  any  materials   not  readily   available  or
                       unusually difficult to install or apply.

               (iv)    The  performance  by Tenant,  or by any company or person
                       employed by Tenant,  of any work at the Premises which in
                       any manner  disrupts  or delays the work at the  Premises
                       that Landlord or Contractor shall be performing; or

               (v)     Any  failure  of Tenant to  cooperate  with  Landlord  or
                       otherwise act in good faith in order to cause the Work to
                       be designed and performed in a timely manner.

7.     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.

                                       6
<PAGE>

       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 $350.60 (3,506
             useable square feet x $.10) 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 may
             cost in excess of $.10 per  square  foot per month due to  Tenant's
             heavy electrical requirements. Landlord's electrical engineer shall
             provide  an  estimate  of  Tenant's  electrical  usage.  Electrical
             engineer's  estimate  shall be based on a  computation  of Tenant's
             electrical  equipment  and  special  heating  and air  conditioning
             requirements,  the amount of amps  required by Tenant's  use of the
             premises  and the  building  kilowatt  charge from  Pacific Gas and
             Electric.

             Electrical  engineer  shall  document  his  calculations  and shall
             submit these  calculations  to Tenant for Tenant's  review.  In the
             event Tenant  questions  any of the  variables  used in  engineer's
             estimate,  the Tenant shall submit  information  to the  electrical
             engineer   sufficient  to  establish  Tenant's  electrical  use  at
             premises. Electrical engineer, Tenant and Landlord shall then agree
             upon correct data to be used in computation of Tenant's  electrical
             usage and  electrical  engineer,  if  necessary,  shall  submit new
             calculations for Tenant's electrical use.

             Landlord  shall bill  Tenant  monthly  for this  excess  electrical
             usage. After the first year of Tenant's occupancy, or sooner should
             Landlord  or  Tenant   require  it,   electrical   engineer   shall
             recalculate the estimate of Tenant's  electrical usage to determine
             the monthly charge for the following year. At this time, any excess
             payments  made  by  Tenant  during  the  preceding  year  would  be
             refunded, or any shortfalls for the preceding year would be paid by
             Tenant.

       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

                                       7
<PAGE>

             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.

8.     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 causes by such removal.

9.     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:    Joseph Pell
                                           ---------------------------------
                                           Joseph Pell

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


                                    By:    Eda Pell
                                           ---------------------------------
                                           Eda Pell

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


                                    Date:  January 14, 1994
                                           ---------------------------------




         TENANT                     Fair, Isaac and Company, Incorporated



                                    By:    Robert D. Sanderson
                                           ---------------------------------


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


                                    Date:  December 28, 1993
                                           ---------------------------------

                                       8