EXHIBIT 32.2


        CERTIFICATION UNDER SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002


         Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, the
undersigned certifies that this periodic report fully complies with the
requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934
and that information contained in this periodic report fairly presents, in all
material respects, the financial condition and results of operations of Fair
Isaac Corporation.


Date:  August 8, 2005                       /s/  CHARLES M. OSBORNE
                                            -----------------------
                                            Charles M. Osborne
                                            Chief Financial Officer