THIRD AMENDMENT TO LEASE

THIS THIRD  AMENDMENT TO LEASE is made and entered into  effective as of the 2nd
day of  December,  1998,  between  CSM  CORPORATION,  a  Minnesota  corporation,
("Landlord") and DYNAMARK, INC., a Minnesota corporation, ("Tenant").


                                    RECITALS

First:        CSM Investors,  Inc. ("CSMI"), as landlord, and DynaMark, Inc., as
              tenant,  entered  into a lease  dated  April  28,  1995,  covering
              certain  premises  located at 4255 Lexington  Avenue North,  Arden
              Hills, Minnesota (the "Lease").

Second:       CSMI's  interest,  as  landlord,  in the Lease was assigned to CSM
              Corporation,  pursuant to an Assignment and  Assumption  Agreement
              dated  September 12, 1995,  whereupon CSM  Corporation  became the
              landlord under the Lease.

Third:        The parties have executed a First Amendment to Lease,  dated March
              11,  1997,  clarifying  their  respective  rights and  obligations
              concerning the "Excess Land" described in the First Amendment.

Fourth:       The  parties  have  executed a Second  Amendment  to Lease,  dated
              November  25,  1997,  extending  the Initial Term of the Lease and
              establishing the rents payable thereunder during such period.

Fifth:        The  parties  wish to  execute  this Third  Amendment  to Lease to
              further  extend the term of the Lease and to  establish  the rents
              payable thereunder during such period:


                                    AGREEMENT

In  consideration  of  the  above  stated  premises  and  the  mutual  covenants
hereinafter  contained,  the parties  hereby  agree that the Lease is  modified,
amended and/or supplemented as follows:

1.       Premises.  The Premises and certain improvements thereupon shall be and
         are  hereby  modified  as shown on the site  plan  attached  hereto  as
         REVISED   EXHIBIT  A.  REVISED   EXHIBIT  A  replaces  and  his  hereby
         substituted  for  Exhibit A attached to the First  Amendment  to Lease.
         Tenant acknowledges that the Premises are a part of a development which
         will include four  buildings and associated  appurtenant  improvements,
         all as shown on REVISED EXHIBIT A. Tenant  acknowledges and agrees that
         the Premises will be subject to and benefitted by various non-exclusive
         easements  for  ingress,  egress and  access  over the  private  drives
         serving the Project,  and certain exclusive easements for utilities and
         other purposes, provided that the same shall not interfere with the use
         and enjoyment of the Premises, as contemplated herein.

2.       Lease Term.  Landlord and Tenant are parties to a lease agreement dated
         December 2, 1998 (the "New Lease"), covering certain premises and a new
         building to be constructed  thereon  located  adjacent to the Premises,
         all as shown on REVISED  EXHIBIT A. The parties  agree that the term of
         the Lease  shall be  adjusted  such that the term of the Lease shall be
         coterminous with the term of the New Lease. More particularly, upon the
         commencement  date of the New  Lease,  the term of the  Lease  shall be
         extended  and  shall run for a period of one  hundred  fifty-six  (156)
         months  commencing on the  commencement  date of the New Lease.  If the
         commencement  date of the New  Lease is other  than the  first day of a
         calendar month, then the term of the Lease shall continue in full force
         and effect for a period of one hundred  fifty-six (156) months from and
         after the first day of the month next succeeding the commencement  date
         of the New Lease.  When the commencement date of the New Lease has been
         established, the parties shall execute an

                                       1                           Exhibit 10.41




         addendum  to this Third  Amendment  to Lease,  confirming  the term and
         expiration date of the Lease.

3.       Subsection 1.6(A) of the Lease and Section 2 of the Second Amendment to
         Lease are  hereby  deleted  in their  entirety  and  replaced  with the
         following:

         "Base Rent. The Base Rental for the Premises  during the remaining term
         of this Lease shall be as follows:

                                                   Monthly              Per
         Period                                   Base Rent         Square Foot
         ------                                   ---------         -----------
         11/1/98 - 8/31/00                       $23,375.00            $8.50
         09/1/00 - 12/31/06                      $24,750.00            $9.00
         01/1/07 - New Lease expiration date     $26,125.00            $9.50

         Option Term:
         ------------
         60 months following the
            New Lease expiration date              market              market

         Landlord  and Tenant  agree that the as built area of the  Premises  is
         33,000 square feet."

4.       Remodeling Allowance. Landlord agrees to provide Tenant with a one time
         allowance for remodeling the Premises.  Landlord's maximum contribution
         towards the costs of  remodeling  will be based upon the time that such
         remodeling occurs, in accordance with the following schedule:

                  Period of                          Maximum Allowance
                  Remodeling Expenditure             Amount Per Square Foot
                  ----------------------             ----------------------
                  1/1/01 - 12/31/02                           $3.00
                  1/1/03 - 12/31/04                           $3.75
                  1/1/05 - 12/31/06                           $4.50
                  1/1/07 - 12/31/08                           $5.25

         The allowance shall apply towards Tenant's actual  remodeling costs and
         shall be payable to Tenant upon completion of remodeling and receipt by
         Landlord of evidence of payment under normal and customary construction
         lending  procedures.  Landlord  shall not be  required  to provide  any
         allowance on costs submitted for reimbursement after December 31, 2010.

4.       Guaranty.  Landlord has  required,  as a condition to its  execution of
         this  third  Amendment  to  Lease,   that  Fair,   Isaac  and  Company,
         Incorporated unconditionally guarantee the full performance of Tenant's
         obligations under the Lease, as amended.  Tenant agrees to deliver such
         guaranty,  in the form of  EXHIBIT C attached  hereto and  incorporated
         herein by reference,  within ten (10) days following the full execution
         of this Third  Amendment to Lease by Landlord and Tenant.  In the event
         Tenant fails to deliver  such  guaranty,  Landlord  may, at its option,
         terminate  this Third  Amendment  to Lease  upon five (5) days  written
         notice to Tenant.

5.       Section  14.12 of the Lease is deleted in its  entirety and is replaced
         with the following:

         "Option to Extend.  Subject to the terms and conditions hereinafter set
         forth,  Tenant  shall  have the option to extend the term of this Lease
         for one (1) additional  sixty (60) month term ("Option  Term") upon and
         pursuant to the same conditions  contained  herein.  This option may be
         exercised by written  notice of exercise from Tenant to Landlord  given
         not less than one (1) year prior to the  expiration  of the Lease Term.
         Tenant may  exercise  this option only if: (i) no  condition of default
         exists with respect to Tenant's  performance of its  obligations  under
         the Lease; and (ii) Tenant simultaneously  exercises all of its options
         to extend under the New Lease and under the Existing Lease covering the
         premises  located  at 4295  Lexington  Avenue  North  in  Arden  Hills,
         Minnesota (as defined in Section 14.12 of the New Lease). Base Rent for
         the Option Term shall be at the fair

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         market rate for comparable space in the north suburban geographic area.
         The fair market rent shall be agreed upon by Tenant and Landlord within
         sixty  (60) days of  Tenant's  notice to  Landlord  of its  irrevocable
         intent to  exercise  its  option to extend set forth  herein.  The fair
         market  rental  rate  shall  be  determined  in  accordance   with  the
         definition  set forth in Section 7 of the  Existing  Lease dated May 1,
         1995 and amended  December  30, 1996 for the  premises  located at 4295
         Lexington  Avenue  North in Arden Hills,  Minnesota.  In the event that
         Landlord and Tenant fail to agree to the fair market rental rate in the
         time  period  set forth  herein,  then the fair  market  rent  shall be
         established in accordance with the arbitration  procedures set forth in
         section  8 of the  Existing  Lease  for the  premises  located  at 4295
         Lexington  Avenue North in Arden Hills,  Minnesota.  If Tenant fails to
         exercise this option as  aforesaid,  this option shall be null and void
         and of no further force and effect."

6.       Miscellaneous.  Except as  expressly  stated  herein,  the Lease  shall
         remain unchanged and in full force and effect.

IN WITNESS WHEREOF, the parties hereto have caused this Third Amendment to Lease
to be executed the day and year first above written.

LANDLORD:                                   TENANT:

CSM CORPORATION                             DYNAMARK, INC.


BY: _______________________________         BY: _______________________________

ITS: _______________________________        ITS: _______________________________

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