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                                                                    EXHIBIT 4.05

                                HNC SOFTWARE INC.

                             1998 STOCK OPTION PLAN

                          As Adopted February 13, 1998
  and Amended March 20, 1998(1), November 9, 1999(2) and September 1, 2000(3)



             1.      PURPOSE. The purpose of this Plan is to provide incentives
to attract, retain and motivate eligible persons whose present and potential
contributions are important to the success of the Company, its Parent,
Subsidiaries and Affiliates, by offering them an opportunity to participate in
the Company's future performance through awards of Options. Capitalized terms
not defined in the text are defined in Section 21.

             2.      SHARES SUBJECT TO THE PLAN.

                     2.1 Number of Shares Available. Subject to Sections 2.2 and
16, the total number of Shares reserved and available for grant and issuance
pursuant to this Plan will be 2,980,000 Shares plus any Shares that are made
available for grant and issuance under this Plan pursuant to the following
sentence. Subject to Sections 2.2 and 16, Shares that are subject to issuance
upon exercise of an Option but cease to be subject to such Option for any reason
other than exercise of such Option will again be available for grant and
issuance in connection with future Options under this Plan. At all times the
Company shall reserve and keep available a sufficient number of Shares as shall
be required to satisfy the requirements of all outstanding Options granted under
this Plan.

                     2.2 Adjustment of Shares. In the event that the number of
outstanding Shares is changed by a stock dividend, recapitalization, stock
split, reverse stock split, subdivision, combination, reclassification or
similar change in the capital structure of the Company without consideration, or
in the event of a change in the corporate structure, capitalization or a
dividend of property affecting the value of the Company's Shares, appropriate
adjustments may be made by the Board in the number of Shares reserved for
issuance under this Plan and the Exercise Prices of and number of Shares subject
to outstanding Options, subject to any required action by the stockholders of
the Company and compliance with applicable securities laws; provided, however,
that fractions of a Share will not be issued but will either be replaced by a
cash payment equal to the Fair Market Value of such fraction of a Share or will
be rounded up to the nearest whole Share, as determined by the Committee.

             3.      ELIGIBILITY. All Options issued under the Plan shall be
nonqualified stock options. Options may be granted to employees, officers,
consultants, independent contractors and advisors of the Company or any Parent,
Subsidiary or Affiliate of the Company; provided that Options awarded to
officers of the Company or any Parent, Subsidiary or Affiliate of the Company
may not exceed 30% of all Options that are available for grant under the Plan
and provided further that such consultants, independent contractors and advisors
render bona fide services not in connection with the offer and sale of
securities in a capital-raising transaction. No person will be eligible to
receive more than 100,000 Shares in any calendar year under this Plan pursuant
to the grant of Options hereunder, other than new employees of the Company or of
a Parent, Subsidiary or Affiliate of the Company who are eligible to receive up
to a maximum of 150,000 Shares in the calendar year in which they commence their
employment. A person may be granted more than one Option under this Plan.


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(1) The Plan was amended on March 20, 1998 solely to increase the number of
    shares reserved under the Plan from 1,000,000 to 1,230,000 shares.

(2) The Plan was amended by Unanimous Written Consent of the Board of Directors
    on November 9, 1999, solely to restate Section 2.2 in its entirety.

(3) The Plan was amended on September 1, 2000 to increase the number of shares
    reserved under the Plan from 1,230,000 to 2,980,000 shares and to increase
    the calendar year individual grant limitations.



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             4.      ADMINISTRATION.

                     4.1 Committee Authority. This Plan will be administered by
the Committee or by the Board acting as the Committee. Subject to the general
purposes, terms and conditions of this Plan, and to the direction of the Board,
the Committee will have full power to implement and carry out this Plan. Without
limitation, the Committee will have the authority to:

             (a)     construe and interpret this Plan, any Stock Option
                     Agreement and any other agreement or document executed
                     pursuant to this Plan;

             (b)     prescribe, amend and rescind rules and regulations relating
                     to this Plan;

             (c)     select persons to receive Options;

             (d)     determine the form and terms of Options;

             (e)     determine the number of Shares or other consideration
                     subject to Options;

             (f)     determine whether Options will be granted singly, in
                     combination with, in tandem with, in replacement of, or as
                     alternatives to, other Options under this Plan or any other
                     incentive or compensation plan of the Company or any
                     Parent, Subsidiary or Affiliate of the Company;

             (g)     grant waivers of Plan or Option conditions;

             (h)     determine the vesting, exercisability and payment of
                     Options;

             (i)     correct any defect, supply any omission or reconcile any
                     inconsistency in this Plan, any Option or any Stock Option
                     Agreement;

             (j)     determine whether an Option has been earned; and

             (k)     make all other determinations necessary or advisable for
                     the administration of this Plan.

                     4.2 Committee Discretion. Any determination made by the
Committee with respect to any Option will be made in its sole discretion at the
time of grant of the Option or, unless in contravention of any express term of
this Plan or Option, at any later time, and such determination will be final and
binding on the Company and on all persons having an interest in any Option under
this Plan. The Committee may delegate to one or more officers of the Company the
authority to grant Options under this Plan.

             5.      OPTIONS. The Committee may grant Options to eligible
persons and will determine the number of Shares subject to the Option, the
Exercise Price of the Option, the period during which the Option may be
exercised, and all other terms and conditions of the Option, subject to the
following:

                     5.1 Form of Option Grant. Each Option granted under this
Plan will be evidenced by a Stock Option Agreement, which will be in such form
and contain such provisions (which need not be the same for each Participant) as
the Committee may from time to time approve, and which will comply with and be
subject to the terms and conditions of this Plan.

                     5.2 Date of Grant. The date of grant of an Option will be
the date on which the Committee makes the determination to grant such Option,
unless otherwise specified by the Committee. The Stock Option Agreement and a
copy of this Plan will be delivered to the Participant within a reasonable time
after the granting of the Option.



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                     5.3 Exercise Period. Options will be exercisable within the
times or upon the events determined by the Committee as set forth in the Stock
Option Agreement governing such Option; provided, however, that no Option will
be exercisable after the expiration of ten (10) years from the date the Option
is granted. The Committee also may provide for the exercise of Options to become
exercisable at one time or from time to time, periodically or otherwise, in such
number of Shares or percentage of Shares as the Committee determines.

                     5.4 Exercise Price. The Exercise Price of an Option will be
determined by the Committee when the Option is granted and may not be less than
100% of the Fair Market Value of the Shares on the date of grant. Payment for
the Shares purchased may be made in accordance with Section 6 of this Plan.

                     5.5 Method of Exercise. Options may be exercised only by
delivery to the Company of a written stock option exercise agreement (the
"EXERCISE AGREEMENT") in a form approved by the Committee (which need not be the
same for each Participant), stating the number of Shares being purchased, the
restrictions imposed on the Shares purchased under such Exercise Agreement, if
any, and such representations and agreements regarding Participant's investment
intent and access to information and other matters, if any, as may be required
or desirable by the Company to comply with applicable securities laws, together
with payment in full of the Exercise Price for the number of Shares being
purchased.

                     5.6 Termination. Notwithstanding the exercise periods set
forth in the Stock Option Agreement, exercise of an Option will always be
subject to the following:

             (a)     If the Participant is Terminated for any reason except
                     death or Disability, then the Participant may exercise such
                     Participant's Options only to the extent that such Options
                     would have been exercisable upon the Termination Date no
                     later than three (3) months after the Termination Date (or
                     such shorter or longer time period not exceeding five (5)
                     years as may be determined by the Committee), but in any
                     event, no later than the expiration date of the Options.

             (b)     If the Participant is Terminated because of Participant's
                     death or Disability (or the Participant dies within three
                     (3) months after a Termination other than because of
                     Participant's death or disability), then Participant's
                     Options may be exercised only to the extent that such
                     Options would have been exercisable by Participant on the
                     Termination Date and must be exercised by Participant (or
                     Participant's legal representative or authorized assignee)
                     no later than twelve (12) months after the Termination Date
                     (or such shorter or longer time period not exceeding five
                     (5) years as may be determined by the Committee), but in
                     any event no later than the expiration date of the Options.

                     5.7 Limitations on Exercise. The Committee may specify a
reasonable minimum number of Shares that may be purchased on any exercise of an
Option, provided that such minimum number will not prevent Participant from
exercising the Option for the full number of Shares for which it is then
exercisable.

                     5.8 Modification, Extension or Renewal. The Committee may
modify, extend or renew outstanding Options and authorize the grant of new
Options in substitution therefor, provided that any such action may not, without
the written consent of a Participant, impair any of such Participant's rights
under any Option previously granted. The Committee may reduce the Exercise Price
of outstanding Options without the consent of Participants affected by a written
notice to them; provided, however, that the Exercise Price may not be reduced
below the minimum Exercise Price that would be permitted under Section 5.4 of
this Plan for Options granted on the date the action is taken to reduce the
Exercise Price.

             6.      PAYMENT FOR SHARE PURCHASES.

                     6.1 Payment. Payment for Shares purchased pursuant to this
Plan may be made in cash (by check) or, where expressly approved for the
Participant by the Committee and where permitted by law:



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             (a)     by cancellation of indebtedness of the Company to the
                     Participant;

             (b)     by surrender of shares that either: (1) have been owned by
                     Participant for more than six (6) months and have been paid
                     for within the meaning of SEC Rule 144 (and, if such shares
                     were purchased from the Company by use of a promissory
                     note, such note has been fully paid with respect to such
                     shares); or (2) were obtained by Participant in the public
                     market;

             (c)     by tender of a full recourse promissory note having such
                     terms as may be approved by the Committee and bearing
                     interest at a rate sufficient to avoid imputation of income
                     under Sections 483 and 1274 of the Code; provided, however,
                     that Participants who are not employees of the Company will
                     not be entitled to purchase Shares with a promissory note
                     unless the note is adequately secured by collateral other
                     than the Shares; provided, further, that the portion of the
                     Exercise Price equal to the par value of the Shares, if
                     any, must be paid in cash;

             (d)     by waiver of compensation due or accrued to the Participant
                     for services rendered; provided, further, that the portion
                     of the Exercise Price equal to the par value of the Shares,
                     if any, must be paid in cash;

             (e)     provided that a public market for the Company's stock
                     exists:

                     (1)    through a "same day sale" commitment from the
                            Participant and a broker-dealer that is a member of
                            the National Association of Securities Dealers (an
                            "NASD DEALER") whereby the Participant irrevocably
                            elects to exercise the Option and to sell a portion
                            of the Shares so purchased to pay for the Exercise
                            Price, and whereby the NASD Dealer irrevocably
                            commits upon receipt of such Shares to forward the
                            Exercise Price directly to the Company; or

                     (2)    through a "margin" commitment from the Participant
                            and a NASD Dealer whereby the Participant
                            irrevocably elects to exercise the Option and to
                            pledge the Shares so purchased to the NASD Dealer in
                            a margin account as security for a loan from the
                            NASD Dealer in the amount of the Exercise Price, and
                            whereby the NASD Dealer irrevocably commits upon
                            receipt of such Shares to forward the Exercise Price
                            directly to the Company; or

             (f)     by any combination of the foregoing.

                     6.2 Loan Guarantees. The Committee may help the Participant
pay for Shares purchased under this Plan by authorizing a guarantee by the
Company of a third-party loan to the Participant.

             7.      WITHHOLDING TAXES.

                     7.1 Withholding Generally. Whenever Shares are to be issued
in satisfaction of Options granted under this Plan, the Company may require the
Participant to remit to the Company an amount sufficient to satisfy federal,
state and local withholding tax requirements prior to the delivery of any
certificate or certificates for such Shares. Whenever, under this Plan, payments
in satisfaction of Options are to be made in cash, such payment will be net of
an amount sufficient to satisfy federal, state, and local withholding tax
requirements.

                     7.2 Stock Withholding. When, under applicable tax laws, a
Participant incurs tax liability in connection with the exercise or vesting of
any Option that is subject to tax withholding and the Participant is obligated
to pay the Company the amount required to be withheld, the Committee may allow
the Participant to satisfy the minimum withholding tax obligation by electing to
have the Company withhold from the Shares to be issued that number of Shares
having a Fair Market Value equal to the minimum amount required to be withheld,



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determined on the date that the amount of tax to be withheld is to be
determined. All elections by a Participant to have Shares withheld for this
purpose will be made in writing in a form acceptable to the Committee.

             8.      PRIVILEGES OF STOCK OWNERSHIP.

                     8.1 Voting and Dividends. No Participant will have any of
the rights of a stockholder with respect to any Shares until the Shares are
issued to the Participant. After Shares are issued to the Participant, the
Participant will be a stockholder and have all the rights of a stockholder with
respect to such Shares, including the right to vote and receive all dividends or
other distributions made or paid with respect to such Shares; provided, that the
Participant will have no right to retain such stock dividends or stock
distributions with respect to Shares that are repurchased at the Participant's
original Exercise Price pursuant to Section 10.

                     8.2 Financial Statements. The Company will provide
financial statements to each Participant prior to such Participant's purchase of
Shares under this Plan, and to each Participant annually during the period such
Participant has Options outstanding; provided, however, the Company will not be
required to provide such financial statements to Participants whose services in
connection with the Company assure them access to equivalent information.

             9.      TRANSFERABILITY. Options granted under this Plan, and any
interest therein, will not be transferable or assignable by Participant, and may
not be made subject to execution, attachment or similar process, otherwise than
by will or by the laws of descent and distribution or as consistent with the
specific Plan and Stock Option Agreement provisions relating thereto. During the
lifetime of the Participant an Option will be exercisable only by the
Participant, and any elections with respect to an Option, may be made only by
the Participant.

             10.     RESTRICTIONS ON SHARES. At the discretion of the Committee,
the Company may reserve to itself and/or its assignee(s) in the Stock Option
Agreement a right to repurchase a portion of or all unvested Shares previously
received upon exercise of an Option and held by a Participant following such
Participant's Termination at any time within ninety (90) days after the later of
Participant's Termination Date and the date Participant purchases Shares under
this Plan, for cash and/or cancellation of purchase money indebtedness, at the
Participant's Exercise Price.

             11.     CERTIFICATES. All certificates for Shares or other
securities delivered under this Plan will be subject to such stock transfer
orders, legends and other restrictions as the Committee may deem necessary or
advisable, including restrictions under any applicable federal, state or foreign
securities law, or any rules, regulations and other requirements of the SEC or
any stock exchange or automated quotation system upon which the Shares may be
listed or quoted.

             12.     ESCROW; PLEDGE OF SHARES. To enforce any restrictions on a
Participant's Shares, the Committee may require the Participant to deposit all
certificates representing Shares, together with stock powers or other
instruments of transfer approved by the Committee, appropriately endorsed in
blank, with the Company or an agent designated by the Company to hold in escrow
until such restrictions have lapsed or terminated, and the Committee may cause a
legend or legends referencing such restrictions to be placed on the
certificates. Any Participant who is permitted to execute a promissory note as
partial or full consideration for the purchase of Shares under this Plan will be
required to pledge and deposit with the Company all or part of the Shares so
purchased as collateral to secure the payment of Participant's obligation to the
Company under the promissory note; provided, however, that the Committee may
require or accept other or additional forms of collateral to secure the payment
of such obligation and, in any event, the Company will have full recourse
against the Participant under the promissory note notwithstanding any pledge of
the Participant's Shares or other collateral. In connection with any pledge of
the Shares, Participant will be required to execute and deliver a written pledge
agreement in such form as the Committee will from time to time approve. The
Shares purchased with the promissory note may be released from the pledge on a
pro rata basis as the promissory note is paid.



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             13.     EXCHANGE AND BUYOUT OF OPTIONS. The Committee may, at any
time or from time to time, authorize the Company, with the consent of the
respective Participants, to issue new Options in exchange for the surrender and
cancellation of any or all outstanding Options. The Committee may at any time
buy from a Participant an Option previously granted with payment in cash, Shares
or other consideration, based on such terms and conditions as the Committee and
the Participant may agree.

             14.     SECURITIES LAW AND OTHER REGULATORY COMPLIANCE. An Option
will not be effective unless such Option is in compliance with all applicable
federal and state securities laws, rules and regulations of any governmental
body, and the requirements of any stock exchange or automated quotation system
upon which the Shares may then be listed or quoted, as they are in effect on the
date of grant of the Option and also on the date of exercise or other issuance.
Notwithstanding any other provision in this Plan, the Company will have no
obligation to issue or deliver certificates for Shares under this Plan prior to:
(a) obtaining any approvals from governmental agencies that the Company
determines are necessary or advisable; and/or (b) completion of any registration
or other qualification of such Shares under any state or federal law or ruling
of any governmental body that the Company determines to be necessary or
advisable. The Company will be under no obligation to register the Shares with
the SEC or to effect compliance with the registration, qualification or listing
requirements of any state securities laws, stock exchange or automated quotation
system, and the Company will have no liability for any inability or failure to
do so.

             15.     NO OBLIGATION TO EMPLOY. Nothing in this Plan or any Option
granted under this Plan will confer or be deemed to confer on any Participant
any right to continue in the employ of, or to continue any other relationship
with, the Company or any Parent, Subsidiary or Affiliate of the Company or limit
in any way the right of the Company or any Parent, Subsidiary or Affiliate of
the Company to terminate Participant's employment or other relationship at any
time, with or without cause.

             16.     CORPORATE TRANSACTIONS.

                     16.1 Assumption or Replacement of Options by Successor. In
the event of (a) a dissolution or liquidation of the Company, (b) a merger or
consolidation in which the Company is not the surviving corporation (other than
a merger or consolidation with a wholly-owned subsidiary, a reincorporation of
the Company in a different jurisdiction, or other transaction in which there is
no substantial change in the stockholders of the Company or their relative stock
holdings and the Options granted under this Plan are assumed, converted or
replaced by the successor corporation, which assumption will be binding on all
Participants), (c) a merger in which the Company is the surviving corporation
but after which the stockholders of the Company (other than any stockholder
which merges (or which owns or controls another corporation which merges) with
the Company in such merger) cease to own their shares or other equity interests
in the Company, (d) the sale of substantially all of the assets of the Company,
or (e) any other transaction which qualifies as a "corporate transaction" under
Section 424(a) of the Code wherein the stockholders of the Company give up all
of their equity interest in the Company (except for the acquisition, sale or
transfer of all or substantially all of the outstanding shares of the Company
from or by the stockholders of the Company), any or all outstanding Options may
be assumed, converted or replaced by the successor corporation (if any), which
assumption, conversion or replacement will be binding on all Participants. In
the alternative, the successor corporation may substitute equivalent Options or
provide substantially similar consideration to Participants as was provided to
stockholders (after taking into account the existing provisions of the Options).
The successor corporation may also issue, in place of outstanding Shares of the
Company held by the Participant, substantially similar shares or other property
subject to repurchase restrictions no less favorable to the Participant. In the
event such successor corporation (if any) refuses to assume or substitute
Options, as provided above, pursuant to a transaction described in this
Subsection 16.1, such Options will expire on such transaction at such time and
on such conditions as the Board will determine.

                     16.2 Other Treatment of Options. Subject to any greater
rights granted to Participants under the foregoing provisions of this Section
16, in the event of the occurrence of any transaction described in Section 16.1,
any outstanding Options will be treated as provided in the applicable agreement
or plan of merger, consolidation, dissolution, liquidation, sale of assets or
other "corporate transaction."



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                     16.3 Assumption of Options by the Company. The Company,
from time to time, also may substitute or assume outstanding options granted by
another company, whether in connection with an acquisition of such other company
or otherwise, by either; (a) granting an Option under this Plan in substitution
of such other company's option; or (b) assuming such option as if it had been
granted under this Plan if the terms of such assumed option could be applied to
an Option granted under this Plan. Such substitution or assumption will be
permissible if the holder of the substituted or assumed option would have been
eligible to be granted an Option under this Plan if the other company had
applied the rules of this Plan to such grant. In the event the Company assumes
an option granted by another company, the terms and conditions of such option
will remain unchanged (except that the exercise price and the number and nature
of Shares issuable upon exercise of any such option will be adjusted
appropriately pursuant to Section 424(a) of the Code). In the event the Company
elects to grant a new Option rather than assuming an existing option, such new
Option may be granted with a similarly adjusted Exercise Price.

             17.     ADOPTION AND EFFECTIVE DATE. This Plan will become
effective on the date that it is adopted by the Board (the "EFFECTIVE DATE").

             18.     TERM OF PLAN. Unless earlier terminated as provided herein,
this Plan will terminate ten (10) years from the Effective Date.

             19.     AMENDMENT OR TERMINATION OF PLAN. The Board may at any time
terminate or amend this Plan in any respect, including without limitation
amendment of any form of Stock Option Agreement or instrument to be executed
pursuant to this Plan; provided, however, that no amendments may be made to
outstanding Options without the consent of the Participant.

             20.     NONEXCLUSIVITY OF THE PLAN. Neither the adoption of this
Plan by the Board nor any provision of this Plan will be construed as creating
any limitations on the power of the Board to adopt such additional compensation
arrangements as it may deem desirable, including, without limitation, the
granting of stock options otherwise than under this Plan, and such arrangements
may be either generally applicable or applicable only in specific cases.

             21.     DEFINITIONS. As used in this Plan, the following terms will
have the following meanings:

                     "AFFILIATE" means any corporation that directly, or
indirectly through one or more intermediaries, controls or is controlled by, or
is under common control with, another corporation, where "control" (including
the terms "controlled by" and "under common control with") means the possession,
direct or indirect, of the power to cause the direction of the management and
policies of the corporation, whether through the ownership of voting securities,
by contract or otherwise.

                     "BOARD" means the Board of Directors of the Company.

                     "CODE" means the Internal Revenue Code of 1986, as amended.

                     "COMMITTEE" means the committee appointed by the Board to
administer this Plan, or if no such committee is appointed, the Board.

                     "COMPANY" means HNC Software Inc., a corporation organized
under the laws of the State of Delaware, or any successor corporation.

                     "DISABILITY" means a disability, whether temporary or
permanent, partial or total, within the meaning of Section 22(e)(3) of the Code,
as determined by the Committee.

                     "EXERCISE PRICE" means the price at which a holder of an
Option may purchase the Shares issuable upon exercise of the Option.



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                     "FAIR MARKET VALUE" means, as of any date, the value of a
share of the Company's Common Stock determined as follows:

             (a)     if such Common Stock is then quoted on the Nasdaq National
                     Market, its closing price on the Nasdaq National Market on
                     the date of determination (if such day is a trading day) as
                     reported in The Wall Street Journal, and, if such date of
                     determination is not a trading day, then on the last
                     trading day prior to the date of determination;

             (b)     if such Common Stock is publicly traded and is then listed
                     on a national securities exchange, its closing price on the
                     last trading day prior to the date of determination on the
                     principal national securities exchange on which the Common
                     Stock is listed or admitted to trading as reported in The
                     Wall Street Journal;

             (c)     if such Common Stock is publicly traded but is not quoted
                     on the Nasdaq National Market nor listed or admitted to
                     trading on a national securities exchange, the average of
                     the closing bid and asked prices on the last trading day
                     prior to the date of determination as reported in The Wall
                     Street Journal; or

             (d)     if none of the foregoing is applicable, by the Committee in
                     good faith.

                     "OPTION" means an award of a nonqualified stock option to
purchase Shares pursuant to Section 5.

                     "PARENT" means any corporation (other than the Company) in
an unbroken chain of corporations ending with the Company, if at the time of the
granting of an Option under this Plan, each of such corporations other than the
Company owns stock possessing 50% or more of the total combined voting power of
all classes of stock in one of the other corporations in such chain.

                     "PARTICIPANT" means a person who receives an Option under
this Plan.

                     "PLAN" means this HNC Software Inc. 1998 Stock Option Plan,
as amended from time to time.

                     "SEC" means the Securities and Exchange Commission.

                     "SHARES" means shares of the Company's Common Stock
reserved for issuance under this Plan, as adjusted pursuant to Sections 2 and
16, and any successor security.

                     "STOCK OPTION AGREEMENT" means, with respect to each
Option, the signed written agreement between the Company and the Participant
setting forth the terms and conditions of the Option.

                     "SUBSIDIARY" means any corporation (other than the Company)
in an unbroken chain of corporations beginning with the Company if, at the time
of granting of the Option, each of the corporations other than the last
corporation in the unbroken chain owns stock possessing 50% or more of the total
combined voting power of all classes of stock in one of the other corporations
in such chain.

                     "TERMINATION" or "TERMINATED" means, for purposes of this
Plan with respect to a Participant, that the Participant has for any reason
ceased to provide services as an employee, officer, consultant, independent
contractor or advisor to the Company or a Parent, Subsidiary or Affiliate of the
Company, except in the case of sick leave, military leave, or any other leave of
absence approved by the Committee, provided that such leave is for a period of
not more than ninety (90) days, or reinstatement upon the expiration of such
leave is guaranteed by contract or statute. The Committee will have sole
discretion to determine whether a Participant has ceased to



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provide services and the effective date on which the Participant ceased to
provide services (the "TERMINATION DATE").



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               ADDENDUM 1 AS ADOPTED BY THE BOARD ON JULY 22, 1998
                 TO THE HNC SOFTWARE INC. 1998 STOCK OPTION PLAN

This Addendum to the Plan concerns Awards granted to employees of the Company or
of a Parent, Subsidiary or Affiliate of the Company residing in Australia
("Australian Participants"). Capitalized terms are defined in the 1998 Stock
Option Plan.

        A Section 5.9 will be added to the Plan as follows:

        Options will be treated as nonqualified stock options for Australian tax
        purposes if immediately after the acquisition of the Share or Option,
        the Participant directly or by attribution owns more than five percent
        (5%) of all classes of stock of the Company or of any Parent or
        Subsidiary of the Company; or immediately after the acquisition of the
        Share or Option, the Participant is in a position to vote, or control
        the voting of more than five percent (5%) of the maximum number of votes
        that may be cast at a general meeting of the Company.

All provisions of the Plan which are not expressly changed by this Addendum
shall remain unchanged. In the event of any conflicts between the provisions of
the Plan and this Addendum with respect to Awards of "Australian Participants,"
the terms of this Addendum shall be controlling.


               ADDENDUM 2 AS ADOPTED BY THE BOARD ON JULY 22, 1998
                 TO THE HNC SOFTWARE INC. 1998 STOCK OPTION PLAN

This Addendum to the Plan concerns Awards granted to employees of the Company or
of a Parent, Subsidiary or Affiliate of the Company residing in Canada
("Canadian Participants"). Capitalized terms are defined in the 1998 Stock
Option Plan.

        Section 2.2 of the Plan shall be modified immediately following
        "provided, however" by replacing the remaining text of that Section 2.2
        with the language set forth below:

        that fractions of a Share will not be issued but will either be replaced
        by a cash payment equal to the Fair Market Value of such fraction of a
        Share or will be rounded down to the nearest whole Share, as determined
        by the Committee.

All provisions of the Plan which are not expressly changed by this Addendum
shall remain unchanged. In the event of any conflicts between the provisions of
the Plan and this Addendum with respect to the subject matter of Awards of
"Canadian Participants," the terms of this Addendum shall be controlling.



                                      -10-
   11




                                HNC SOFTWARE INC.

                             1998 STOCK OPTION PLAN

                             STOCK OPTION AGREEMENT


               This Stock Option Agreement (this "AGREEMENT") is made and
entered into as of the date of grant set forth below (the "DATE OF GRANT") by
and between HNC Software Inc., a Delaware corporation (the "COMPANY"), and the
participant named below ("PARTICIPANT"). Capitalized terms not defined herein
shall have the meaning ascribed to them in the Company's 1998 Stock Option Plan,
as amended (the "PLAN").

PARTICIPANT:                       _________________________________

SOCIAL SECURITY NUMBER:            _________________________________

PARTICIPANT'S ADDRESS:             _________________________________

                                   _________________________________

TOTAL OPTION SHARES:               _________________________________

EXERCISE PRICE PER SHARE:          _________________________________

DATE OF GRANT:                     _________________________________

VESTING START DATE:                _________________________________

EXPIRATION DATE:                   _________________________________


             1.      GRANT OF OPTION. The Company hereby grants to Participant a
nonqualified stock option (this "OPTION") to purchase up to the total number of
shares of Common Stock of the Company set forth above (collectively, the
"SHARES") at the Exercise Price Per Share set forth above (the "EXERCISE
PRICE"), subject to all of the terms and conditions of this Agreement and the
Plan.

             2.      VESTING; EXERCISE PERIOD.

                     2.1 Vesting of Right to Exercise Option. This Option shall
become exercisable as to portions of the Shares as follows: (a) this Option
shall not be exercisable with respect to any of the Shares until __________,
199__ (the "FIRST VESTING DATE"); (b) if Participant has continuously provided
services to the Company or any Subsidiary, Parent or Affiliate of the Company
from the Date of Grant through the First Vesting Date and has not been
Terminated on or before the First Vesting Date, then on the First Vesting Date
this Option shall become exercisable as to _____ percent (_____%) of the Shares;
and (c) thereafter, so long as Participant continuously provides services to the
Company or any Subsidiary, Parent or Affiliate of the Company and is not
Terminated, on the first anniversary of the First Vesting Date and on each
successive anniversary of the First Vesting Date thereafter, this Option shall
become exercisable



                                      -11-
   12

as to an additional ______ percent (___%) of the Shares; provided that this
Option shall in no event ever become exercisable with respect to more than 100%
of the Shares.

                     2.2 Expiration. This Option shall expire on the Expiration
Date set forth above and must be exercised, if at all, on or before the earlier
of the Expiration Date or the date on which this Option is earlier terminated in
accordance with the provisions of Section 3.

             3.      TERMINATION.

                     3.1 Termination for Any Reason Except Death or Disability.
If Participant is Terminated for any reason, except Participant's death or
Disability, then this Option, to the extent (and only to the extent) that it
would have been exercisable by Participant on the date of Termination, may be
exercised by Participant no later than three (3) months after the date of
Termination (or seven (7) months after the date of Termination if the Company is
then subject to Section 16 of the Exchange Act and Participant's transactions in
securities of the Company were subject to Section 16(b) of the Exchange Act on
the date of Termination), but in any event no later than the Expiration Date.

                     3.2 Termination Because of Death or Disability. If
Participant is Terminated because of death or Disability of Participant, then
this Option, to the extent that it is exercisable by Participant on the date of
Termination, may be exercised by Participant (or Participant's legal
representative) no later than twelve (12) months after the date of Termination,
but in any event no later than the Expiration Date.

                     3.3 No Obligation to Employ. Nothing in the Plan or this
Agreement shall confer on Participant any right to continue in the employ of, or
other relationship with, the Company or any Parent, Subsidiary or Affiliate of
the Company, or limit in any way the right of the Company or any Parent,
Subsidiary or Affiliate of the Company to terminate Participant's employment or
other relationship at any time, with or without cause.

             4.      MANNER OF EXERCISE.

                     4.1 Stock Option Exercise Agreement. To exercise this
Option, Participant (or in the case of exercise after Participant's death,
Participant's executor, administrator, heir or legatee, as the case may be) must
deliver to the Company an executed stock option exercise agreement in the form
attached hereto as Exhibit A, or in such other form as may be approved by the
Company from time to time (the "EXERCISE AGREEMENT"), which shall set forth,
inter alia, Participant's election to exercise this Option, the number of Shares
being purchased, any restrictions imposed on the Shares and any representations,
warranties and agreements regarding Participant's investment intent and access
to information as may be required by the Company to comply with applicable
securities laws. If someone other than Participant exercises this Option, then
such person must submit documentation reasonably acceptable to the Company that
such person has the right to exercise this Option.



                                      -12-
   13

                     4.2 Limitations on Exercise. This Option may not be
exercised unless such exercise is in compliance with all applicable federal and
state securities laws, as they are in effect on the date of exercise. This
Option may not be exercised as to fewer than 100 Shares unless it is exercised
as to all Shares as to which this Option is then exercisable.

                     4.3 Payment. The Exercise Agreement shall be accompanied by
full payment of the Exercise Price for the Shares being purchased in cash (by
check), or where permitted by law:

                           (a)     by cancellation of indebtedness of the
                                   Company to the Participant;

                           (b)     by surrender of shares of the Company's
                                   Common Stock that either: (1) have been owned
                                   by Participant for more than six (6) months
                                   and have been paid for within the meaning of
                                   SEC Rule 144 (and, if such shares were
                                   purchased from the Company by use of a
                                   promissory note, such note has been fully
                                   paid with respect to such shares); or (2)
                                   were obtained by Participant in the open
                                   public market; and (3) are clear of all
                                   liens, claims, encumbrances or security
                                   interests;

                           (c)     by tender of a full recourse promissory note
                                   having such terms as may be approved by the
                                   Committee and bearing interest at a rate
                                   sufficient to avoid imputation of income
                                   under Sections 483 and 1274 of the Code;
                                   provided, however, that Participants who are
                                   not employees of the Company shall not be
                                   entitled to purchase Shares with a promissory
                                   note unless the note is adequately secured by
                                   collateral other than the Shares; and
                                   provided further that the portion of the
                                   Exercise Price equal to the par value of the
                                   Shares, if any, must be paid in cash;

                           (d)     by waiver of compensation due or accrued to
                                   Participant for services rendered;

                           (e)     provided that a public market for the
                                   Company's stock exists: (1) through a "same
                                   day sale" commitment from Participant and a
                                   broker-dealer that is a member of the
                                   National Association of Securities Dealers
                                   (an "NASD DEALER") whereby Participant
                                   irrevocably elects to exercise this Option
                                   and to sell a portion of the Shares so
                                   purchased to pay for the exercise price and
                                   whereby the NASD Dealer irrevocably commits
                                   upon receipt of such Shares to forward the
                                   exercise price directly to the Company; or
                                   (2) through a "margin" commitment from
                                   Participant and a NASD Dealer whereby



                                      -13-
   14

                                   Participant irrevocably elects to exercise
                                   this Option and to pledge the Shares so
                                   purchased to the NASD Dealer in a margin
                                   account as security for a loan from the NASD
                                   Dealer in the amount of the exercise price,
                                   and whereby the NASD Dealer irrevocably
                                   commits upon receipt of such Shares to
                                   forward the exercise price directly to the
                                   Company; or

                           (f)     by any combination of the foregoing.

                     4.4 Tax Withholding. Prior to the issuance of the Shares
upon exercise of this Option, Participant must pay or provide for any applicable
federal or state withholding obligations of the Company. If the Committee
permits, Participant may provide for payment of withholding taxes upon exercise
of this Option by requesting that the Company retain Shares with a Fair Market
Value equal to the minimum amount of taxes required to be withheld. In such
case, the Company shall issue the net number of Shares to the Participant by
deducting the Shares retained from the Shares issuable upon exercise.

                     4.5 Issuance of Shares. Provided that the Exercise
Agreement and payment are in form and substance satisfactory to counsel for the
Company, the Company shall issue the Shares registered in the name of
Participant, Participant's authorized assignee, or Participant's legal
representative, and shall deliver certificates representing the Shares with the
appropriate legends affixed thereto.

             5.      COMPLIANCE WITH LAWS AND REGULATIONS. The exercise of this
Option and the issuance and transfer of Shares shall be subject to compliance by
the Company and Participant with all applicable requirements of federal and
state securities laws and with all applicable requirements of any stock exchange
on which the Company's Common Stock may be listed at the time of such issuance
or transfer. Participant understands that the Company is under no obligation to
register or qualify the Shares with the Securities and Exchange Commission, any
state securities commission or any stock exchange to effect such compliance.

             6.      NONTRANSFERABILITY OF OPTION. This Option may not be
transferred in any manner other than by will or by the laws of descent and
distribution and may be exercised during the lifetime of Participant only by
Participant. The terms of this Option shall be binding upon the executors,
administrators, successors and assigns of Participant.

             7.      TAX CONSEQUENCES. Set forth below is a brief summary as of
the Date of Grant of some of the federal and California tax consequences of
exercise of this Option and disposition of the Shares. THIS SUMMARY IS
NECESSARILY INCOMPLETE, AND THE TAX LAWS AND REGULATIONS ARE SUBJECT TO CHANGE.
PARTICIPANT SHOULD CONSULT A TAX ADVISOR BEFORE EXERCISING THE OPTION OR
DISPOSING OF THE SHARES.

                     7.1 Exercise of Nonqualified Stock Option. There may be a
regular federal and California income tax liability upon the exercise of this
Option. Participant will be



                                      -14-
   15

treated as having received compensation income (taxable at ordinary income tax
rates) equal to the excess, if any, of the fair market value of the Shares on
the date of exercise over the Exercise Price. The Company will be required to
withhold from Participant's compensation or collect from Participant and pay to
the applicable taxing authorities an amount equal to a percentage of this
compensation income at the time of exercise.

                     7.2 Disposition of Shares. If the Shares are held for more
than twelve (12) months after the date of the transfer of the Shares pursuant to
the exercise of a nonqualified stock option, any gain realized on disposition of
the Shares will be treated as capital gain. The maximum federal capital gain tax
rates are twenty-eight percent (28%) for Shares held more than twelve (12)
months, but not more than eighteen (18) months, and twenty percent (20%) for
Shares held for more than eighteen (18) months.

             8.      PRIVILEGES OF STOCK OWNERSHIP. Participant shall not have
any of the rights of a shareholder with respect to any Shares until Participant
exercises this Option and pays the Exercise Price.

             9.      INTERPRETATION. Any dispute regarding the interpretation of
this Agreement shall be submitted by Participant or the Company to the Committee
for review. The resolution of such a dispute by the Committee shall be final and
binding on the Company and Participant.

             10.     ENTIRE AGREEMENT. The Plan is incorporated herein by
reference. This Agreement and the Plan and the Exercise Agreement constitute the
entire agreement and understanding of the parties hereto with respect to the
subject matter hereof and supersede all prior understandings and agreements with
respect to such subject matter.

             11.     NOTICES. Any notice required to be given or delivered to
the Company under the terms of this Agreement shall be in writing and addressed
to the Corporate Secretary of the Company at its principal corporate offices.
Any notice required to be given or delivered to Participant shall be in writing
and addressed to Participant at the address indicated above or to such other
address as such party may designate in writing from time to time to the Company.
All notices shall be deemed to have been given or delivered upon: personal
delivery; three (3) days after deposit in the United States mail by certified or
registered mail (return receipt requested); one (1) business day after deposit
with any return receipt express courier (prepaid); or one (1) business day after
transmission by rapifax or telecopier.

             12.     SUCCESSORS AND ASSIGNS. The Company may assign any of its
rights under this Agreement. This Agreement shall be binding upon and inure to
the benefit of the successors and assigns of the Company. Subject to the
restrictions on transfer set forth herein, this Agreement shall be binding upon
Participant and Participant's heirs, executors, administrators, legal
representatives, successors and assigns.

             13.     GOVERNING LAW. This Agreement shall be governed by and
construed in accordance with the internal laws of the State of California,
without regard to that body of law pertaining to choice of law or conflict of
law.



                                      -15-
   16

             14.     ACCEPTANCE. Participant hereby acknowledges receipt of a
copy of the Plan and this Agreement. Participant has read and understands the
terms and provisions thereof, and accepts this Option subject to all the terms
and conditions of the Plan and this Agreement. Participant acknowledges that
there may be adverse tax consequences upon exercise of this Option or
disposition of the Shares and that the Company has advised Participant to
consult a tax advisor prior to such exercise or disposition.

            IN WITNESS WHEREOF, the Company has caused this Agreement to be
executed in duplicate by its duly authorized representative and Participant has
executed this Agreement in duplicate as of the Date of Grant.

HNC SOFTWARE INC.                            PARTICIPANT


By:
   --------------------------------          -----------------------------------
                                             (Signature)


- -----------------------------------          -----------------------------------
(Please print name)                          (Please print name)


- -----------------------------------
(Please print title)



                                      -16-
   17

                                    EXHIBIT A


                         STOCK OPTION EXERCISE AGREEMENT



                                      -17-