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                                                                   EXHIBIT 10.13


                              EMPLOYMENT AGREEMENT

         This Agreement is entered into as of September 10, 1996 (the "EFFECTIVE
DATE") by and between Aptex Software Inc., a California corporation (the
"COMPANY"), and Michael A. Thiemann ("EMPLOYEE").

                               W I T N E S S E T H

         WHEREAS, pursuant to a Restricted Stock Purchase Agreement dated of
even date herewith (the "RESTRICTED STOCK PURCHASE AGREEMENT"), Employee is
purchasing 1,000,000 shares of the Company's Common Stock, and has agreed to
subject such shares to the restrictions stated in the Restricted Stock Purchase
Agreement, including certain restrictions relating to Employee's continued
employment with the Company; and

         WHEREAS, the Company and Employee desire that Employee be employed by
the Company upon the terms set forth below;

         NOW, THEREFORE, in consideration of the promises and mutual covenants
contained herein, the parties agree as follows:

         1. EMPLOYMENT AND TERM OF EMPLOYMENT. The Company hereby employs
Employee, and Employee hereby accepts such employment, subject to the terms and
conditions of this Agreement.

         2. OFFICE AND DUTIES. Employee will hold the office of President and
Chief Executive Officer of the Company, reporting to the Company's Board of
Directors (the "BOARD"). Employee will have such duties as the Board may from
time to time designate for Employee. At the discretion and direction of the
Board, Employee will also serve in such other additional capacities with the
Company as the Board may from time to time designate.

         3. EXCLUSIVE SERVICE. Employee agrees that, so long as he is employed
by the Company, he will devote his full time and efforts exclusively to his
employment with the Company and will apply all his skill and experience to the
performance of his duties for the Company. During his employment with the
Company, except with the prior written approval of the Board, Employee will not
engage in, be employed by, or be a significant investor in, any business other
than that of the Company or HNC Software Inc. ("HNC"), except: (i) as a passive
investor owning less than one percent (1%) of the voting stock or voting
interests in a company with securities listed on a national securities exchange
or automated quotation system or registered under the Securities Exchange Act of
1934; or (ii) as a passive investor owning less than five percent (5%) of the
voting stock or voting interests in a privately-held company conducting a
business which in the reasonable judgment of the Board is not competitive with
the business conducted by the Company or HNC. In addition, Employee will not
engage in any consulting activity except with the prior written approval of the
Company, or at the direction of the Company, and Employee will otherwise do
nothing inconsistent with the performance of his duties hereunder. Employee has
executed an agreement regarding proprietary information and inventions with the
Company in the form attached hereto as Exhibit 1 (the "EMPLOYEE
ASSIGNMENT/CONFIDENTIALITY AGREEMENT").
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         4. COMPENSATION AND BENEFITS. In consideration of Employee's
performance of his services for the Company hereunder, so long as Employee is
employed by the Company as its President and Chief Executive Officer, the
Company will pay Employee, and Employee accepts as full compensation for all
services to be rendered to the Company, the following compensation and benefits:

                  (a) Salary. The Company will pay Employee an initial base
salary at the rate of One Hundred Fifty Thousand Dollars ($150,000) per annum.
Such salary will be paid in equal installments in accordance with the Company's
customary payroll schedule. It is understood that Employee's salary will be
reviewed periodically by the Board and may be increased by the Board from time
to time in its sole discretion.

                  (b) Cash Bonus. Employee will be eligible to earn a cash
incentive bonus with respect to his services to the Company during calendar year
1996 in accordance with the terms and conditions of the Bonus Program set forth
in Exhibit 2 hereto. For so long as Employee remains employed by the Company as
its Chief Executive Officer, the parties agree that for each fiscal year of the
Company they will in good faith negotiate an incentive bonus program for
Employee for that fiscal year with a target of a $50,000 bonus payable if the
Company meets (but does not exceed) its financial plan for that fiscal year.

                  (c) Deductions. The Company will deduct and withhold from any
compensation payable to Employee the sums which it is required by law to deduct
and withhold, including but not limited to federal and state withholding taxes,
social security taxes and state disability insurance.

                  (d) Employee Benefits. Employee will be eligible to
participate in the Company's employee benefit plans of general application,
including without limitation those plans (if any) covering pension and profit
sharing, executive bonuses, stock purchases, stock options, and those plans
covering life, health and dental insurance in accordance with the rules
established for the individual participation in any such plan. However, inasmuch
as the Company has not yet adopted any employee benefit plans (other than its
1996 Equity Incentive Plan), initially Employee will (but only to the extent
that, and for so long as, permitted by HNC's employee benefit plans of general
application ("HNC PLANS")) be eligible to participate in such HNC Plans in
accordance with the rules established for individual participation in such HNC
Plans; provided, however, that Employee shall not participate in and/or shall
cease to participate in, any HNC Plan that: (i) does not permit participation by
employees of the Company; (ii) is terminated by HNC, or (iii) which provides
benefits that are of the same general type as the benefits provided under any
employee benefit plan that may be adopted by the Company (whether or not the
scope, level or amount of such benefits is the same).

                  (e) Vacation. Employee initially be entitled to twenty-five
(25) days of paid vacation per year; increasing on July 1, 1999 to thirty (30)
days of paid vacation for each one-year period commencing with the one-year
period that begins on July 1, 1999.

         5. REIMBURSEMENT FOR EXPENSES. The Company will promptly reimburse
Employee for all reasonable and necessary business expenses actually incurred by
Employee in carrying out his duties under this Agreement to the extent that such
expenses are deductible as business expenses on the Company's federal and state
income tax returns provided Employee furnishes to the Company adequate records
to substantiate such deductions.

         6. TERMINATION.


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                  (a) Events of Termination. Employee's employment with the
Company will terminate upon the first to occur of any of the following events:

                           (i) Employee's death;

                           (ii) the good faith determination by the Board that
Employee suffers from any mental or physical illness, disability, incapacity or
incompetency that prevents Employee (or is reasonably likely to prevent
Employee) from performing Employee's duties hereunder for 120 days or more
during any 180-day period;

                           (iii) the determination by the Board that "CAUSE" for
termination exists, which will mean a good faith determination by the Board that
Employee has: (A) committed a material breach of any material term of this
Agreement or the Employee Assignment/Confidentiality Agreement, which breach
continues uncured for a period of thirty (30) days after Employee receives
notice of such breach from the Company; (B) committed an act of fraud or
embezzlement; (C) habitually failed to report for work during normal work hours;
(D) willfully and wrongfully disclosed or permitted any other party to in any
manner use any of the Company's trade secrets; (E) committed an act of willful
misconduct which is seriously prejudicial to the best interests of the Company;
(F) committed a felony; or (G) been under the influence of any unlawful drugs,
controlled substances or alcohol at any time while performing his duties under
this Agreement;

                           (iv) the determination by the Board to terminate
Employee without Cause, which termination will become effective thirty (30) days
following the date of a written notice of termination given by the Company to
Employee; or

                           (v) the voluntary termination or resignation of
employment by Employee, which will become effective thirty (30) days following
the date of a notice of termination or resignation given by Employee to the
Company.

                  (b) Constructive Termination Without Cause. If the Company
changes the duties assigned to Employee solely to duties not reasonably
comparable with those duties typically assigned to a president or chief
executive officer, then such changes in Employee's duties shall be deemed to be
a termination without Cause under Section 6(a)(iv), unless Employee voluntarily
continues his employment with the Company notwithstanding such change in duties.

                  (c) Treatment of Voluntary Termination. If Employee
voluntarily terminates or resigns his employment with the Company, then such
voluntary termination or resignation will be treated in the same manner as a
termination for Cause under Section 6(a)(iii).

                  (d) Compensation Payable Upon Termination.

                           (i) Termination For Cause. If Employee's employment
is terminated with Cause under Section 6(a)(iii) or is treated as having been
terminated for Cause under Section 6(c), then Employee will not be entitled to
any severance compensation, employment benefits or stock or option vesting
(under the Restricted Stock Purchase Agreement or otherwise) after the date of
notice of termination except as provided in Section 6(d)(iii).

                           (ii) Termination Without Cause. If Employee's
employment is terminated without Cause under Section 6(a)(iv) or is treated as
having been terminated without Cause under


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Section 6(b), then Employee will be entitled to severance pay equal to salary
continuation for six (6) months at his then-current base salary, payable in six
(6) equal monthly installments, and the Company's standard life, health and
dental insurance policies will continue in effect during that six (6) month
period to the extent permitted by such policies. No other compensation will be
payable upon such termination without Cause except as expressly provided in
Section 6(d)(iii).

                           (iii) General Termination Provisions. Upon any
termination of Employee's employment with the Company (whether with Cause or
without Cause), Employee shall be entitled, in addition to any payment called
for by Section 6(d)(i) or 6(d)(ii) above, to receive payment of: (A) any accrued
and earned salary as of the Termination Date; (B) any accrued and unused
vacation pay accrued as of the Termination Date; and (C) the portion (if any) of
any bonus that was, under the terms and conditions of the applicable bonus
program, fully accrued and earned by Employee as of the Termination Date without
any risk of forfeiture due to termination of employment.

                           (iv) Termination Date. The term "TERMINATION DATE"
means the effective date of termination of Employee's employment with the
Company. In case of any doubt or dispute, the Board shall have the sole and
exclusive discretion to in good faith determine the Termination Date.

                  (f) Survival of Obligations. Upon any termination of
Employee's employment with the Company, all obligations of the Company under
this Agreement (including without limitation the Company's obligations under
Section 4 hereof), and all rights and obligations of Employee under this
Agreement, will cease and terminate, except for (i) those contained in this
Section 6; and (ii) those contained in the Employee Assignment/Confidentiality
Agreement.

         7. ASSIGNMENT. Since this Agreement is based upon the unique abilities
of and Employee's personal relationship with the Company, Employee will have no
right to assign this Agreement or any of his rights hereunder without the
written consent of the Company, other than the right to cash payments payable to
Employee hereunder, and the Company will have no right to assign any of its
rights hereunder except to a parent, subsidiary or purchaser of substantially
all of the assets of the Company or a company that merges or consolidates with
or into the Company.

         8. ENTIRE AGREEMENT. This Agreement and the Restricted Stock Purchase
Agreement embrace and include the entire employment agreement between the
parties hereto and any prior contract, agreement, letter of intent, term sheet
or other understanding between the parties hereto, is hereby superseded,
canceled and will be of no further force or effect. This Agreement may not be
modified, altered, changed or amended in any respect except by a writing by both
parties hereto.

         9. SEVERABILITY. If any provision of this Agreement is found invalid by
any court of competent jurisdiction, such finding will not affect the validity
of the other provisions hereof, and the invalid provision will be deemed to have
been severed from this Agreement.

         10. NOTICES. Any notice required or permitted to be given under this
Agreement will be sufficient if delivered personally or if given in writing and
sent by certified mail, return receipt requested, to his residence in the case
of Employee or to its principal office in the case of the Company.

         11. GOVERNING LAW. This Agreement is executed in one or more duplicate
original counterparts in the State of California and will be governed by the
internal laws of the State of California.


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         12. FUTURE EMPLOYMENT. Employee agrees that upon termination of his
employment with the Company, the Company may notify anyone thereafter employing
Employee of the existence and provisions of this Agreement.

         13. INJUNCTIVE RELIEF. Employee acknowledges that failure to perform
any duties, obligations, covenants or agreements provided in this Agreement may
result in irreparable injury to the Company. Accordingly, Employee agrees that,
in addition to remedies otherwise available, any or all of said duties,
obligations, covenants and agreements may be enforced by suit, restraining order
and/or injunction.

         14. ATTORNEYS' FEES. In the event of any litigation or other legal
proceeding brought by either party to enforce this Agreement, the prevailing
party will be entitled to recover its reasonable expenses, including attorneys'
fees, incurred in the proceeding, in addition to any damages or other relief
that may be awarded.

         IN WITNESS WHEREOF, Employee has executed this Agreement and the
Company has caused this Agreement to be executed by its duly authorized officer
as of the date and year first written above.

APTEX SOFTWARE INC.,                EMPLOYEE
  A CALIFORNIA CORPORATION



By:____________________________     ____________________________
                                    Michael A. Thiemann
Name:__________________________

Its:___________________________


ATTACHMENTS

Exhibit 1:        Employee Assignment/Confidentiality Agreement
Exhibit 2:        Calendar 1996 Bonus Program


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                    [SIGNATURE PAGE TO EMPLOYMENT AGREEMENT]


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                                        Michael A. Thiemann Employment Agreement


                                    Exhibit 1
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           EMPLOYEE INVENTION ASSIGNMENT AND CONFIDENTIALITY AGREEMENT
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                                        Michael A. Thiemann Employment Agreement

                                    Exhibit 2
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                           CALENDAR 1996 BONUS PROGRAM