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                                                                    EXHIBIT 4.05

                                HNC SOFTWARE INC.

                        1995 DIRECTORS STOCK OPTION PLAN

                             As Adopted May 4, 1995
                         and As Amended March 18, 1999,
                        June 12, 1999, November 9, 1999,
                       March 30, 2000,and April 30, 2000


        1. PURPOSE. This 1995 Directors Stock Option Plan (this "PLAN") is
established to provide equity incentives for nonemployee members of the Board of
Directors of HNC Software Inc. (the "COMPANY"), who are described in Section 6.1
below, by granting such persons options to purchase shares of stock of the
Company.

        2. ADOPTION AND STOCKHOLDER APPROVAL. After this Plan is adopted by the
Board of Directors of the Company (the "BOARD"), this Plan will become effective
on the time and date (the "EFFECTIVE DATE") on which the registration statement
filed by the Company with the Securities and Exchange Commission ("SEC") under
the Securities Act of 1933, as amended (the "SECURITIES ACT"), to register the
initial public offering of the Company's Common Stock is declared effective by
the SEC; provided, however, that if the Effective Date does not occur on or
before December 31, 1995, this Plan will terminate as of December 31, 1995
having never become effective. This Plan shall be approved by the stockholders
of the Company, consistent with applicable laws, within twelve (12) months after
the date this Plan is adopted by the Board. Options ("OPTIONS") may be granted
under this Plan after the Effective Date provided that, in the event that
stockholder approval is not obtained within the time period provided herein,
this Plan, and all Options granted hereunder, shall terminate. No Option that is
issued as a result of any increase in the number of shares authorized to be
issued under this Plan shall be exercised prior to the time such increase has
been approved by the stockholders of the Company and all such Options granted
pursuant to such increase shall similarly terminate if such stockholder approval
is not obtained. So long as the Company is subject to Section 16(b) of the
Securities Exchange Act of 1934, as amended, (the "EXCHANGE ACT") the Company
will comply with the requirements of Rule 16b-3 with respect to stockholder
approval.

        3. TYPES OF OPTIONS AND SHARES. Options granted under this Plan shall be
nonqualified stock options ("NQSOS"). The shares of stock that may be purchased
upon exercise of Options granted under this Plan (the "SHARES") are shares of
the Common Stock of the Company.

        4. NUMBER OF SHARES. The maximum number of Shares that may be issued
pursuant to Options granted under this Plan (the "MAXIMUM NUMBER") is 600,000
Shares, subject to adjustment as provided in this Plan. If any Option is
terminated for any reason without being exercised in whole or in part, the
Shares thereby released from such Option



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shall be available for purchase under other Options subsequently granted under
this Plan. At all times during the term of this Plan, the Company shall reserve
and keep available such number of Shares as shall be required to satisfy the
requirements of outstanding Options granted under this Plan; provided, however
that if the aggregate number of Shares subject to outstanding Options granted
under this Plan plus the aggregate number of Shares previously issued by the
Company pursuant to the exercise of Options granted under this Plan exceeds the
Maximum Number of Shares, then notwithstanding anything herein to the contrary,
no further Options may be granted under this Plan until the Maximum Number is
increased or the aggregate number of Shares subject to outstanding Options
granted under this Plan plus the aggregate number of Shares previously issued by
the Company pursuant to the exercise of Options granted under this Plan is less
than the Maximum Number.

        5. ADMINISTRATION. This Plan shall be administered by the Board or by a
committee of not less than two members of the Board appointed to administer this
Plan (the "COMMITTEE"). As used in this Plan, references to the Committee shall
mean either such Committee or the Board if no Committee has been established.
The interpretation by the Committee of any of the provisions of this Plan or any
Option granted under this Plan shall be final and binding upon the Company and
all persons having an interest in any Option or any Shares purchased pursuant to
an Option.

        6. ELIGIBILITY AND AWARD FORMULA.

            6.1 Eligibility. Options may be granted only to directors of the
Company who are not employees of the Company or any Parent, Subsidiary or
Affiliate of the Company, as those terms are defined in Section 17 below.

            6.2 Initial Grant. Each Optionee who on or after the Effective Date
is or becomes a member of the Board will automatically be granted an Option for
25,000 Shares (the "INITIAL GRANT"). Initial Grants shall be made on the later
of the Effective Date or the date such Optionee first becomes a member of the
Board.

            6.3 Succeeding Grants. On each anniversary of the Initial Grant, if
the Optionee is still a member of the Board and has served continuously as a
member of the Board since the date of the Optionee's Initial Grant, the Optionee
will automatically be granted an Option for 10,000 Shares (a "SUCCEEDING
GRANT").

        7. TERMS AND CONDITIONS OF OPTIONS. Subject to the following and to
Section 6 above:

            7.1 Form of Option Grant. Each Option granted under this Plan shall
be evidenced by a written Stock Option Grant ("GRANT") in such form (which need
not be the same for each Optionee) as the Committee shall from time to time
approve, which Grant shall comply with and be subject to the terms and
conditions of this Plan.

        7.2 Vesting.


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            (a) Options Granted On or After June 20, 1999 and Prior to April 30,
2000. Options granted under this Plan on or after June 20, 1999 and prior to
April 30, 2000 shall be fully vested and exercisable in full on the Start Date
of such Options (as used herein, the date an Optionee is granted an Initial
Grant or a Succeeding Grant is referred to in this Plan as the "START DATE" for
such Option).

            (b) All Other Options. All other Options granted under this Plan
(i.e. all Options granted prior to June 20, 1999 and all Options granted on or
after April 30, 2000) shall become exercisable as they vest according to the
vesting schedule set forth below:

                (i) Initial Grants. Each Option granted prior to June 20, 1999
and each Option granted on or after April 30, 2000 that is an Initial Grant will
vest as follows, so long as the Optionee continuously remains a director of the
Company: (A) on the first (1st) anniversary of the Start Date, the Initial Grant
will vest as to forty percent (40%) of the Shares; (B) on the second (2nd)
anniversary of the Start Date, the Initial Grant will vest as to thirty percent
(30%) of the Shares; (C) on the third (3rd) anniversary of the Start Date, the
Initial Grant will vest as to twenty percent (20%) of the Shares; and (D) on the
fourth (4th) anniversary of the Start Date, the Initial Grant will vest as to
ten percent (10%) of the Shares.

                (ii) Succeeding Grants. Each Option granted prior to June 20,
1999 and each Option granted on or after April 30, 2000 that is a Succeeding
Grant will vest as to twenty-five percent (25%) of the Shares upon each of the
first four (4) successive anniversaries of the Start Date for such Succeeding
Grant, so long as the Optionee continuously remains a director of the Company."

        7.3 Exercise Price. The exercise price of an Option shall be the Fair
Market Value (as defined in Section 17.4) of the Shares, at the time that the
Option is granted.

        7.4 Termination of Option. Except as provided below in this Section,
each Option shall expire ten (10) years after its Start Date (the "EXPIRATION
DATE"). The Option (to the extent it is subject to vesting) shall cease to vest
if the Optionee ceases to be a member of the Board. The date on which the
Optionee ceases to be a member of the Board shall be referred to as the
"TERMINATION DATE". An Option may be exercised after the Termination Date only
as set forth below:

            (a) Termination Generally. If the Optionee ceases to be a member of
the Board for any reason except death or disability, then each Option then held
by such Optionee, to the extent (and only to the extent) that it would have been
exercisable by the Optionee on the Termination Date, may be exercised by the
Optionee within seven (7) months after the Termination Date, but in no event
later than the Expiration Date.

            (b) Death or Disability. If the Optionee ceases to be a member of
the Board because of the death of the Optionee or the disability of the Optionee
within the meaning of Section 22(e)(3) of the Internal Revenue Code of 1986, as
amended (the "CODE"), then each Option then held by such Optionee, to the extent
(and only to the extent) that it would have been exercisable by the Optionee on
the Termination Date, may be


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exercised by the Optionee (or the Optionee's legal representative) within twelve
(12) months after the Termination Date, but in no event later than the
Expiration Date.

        8. EXERCISE OF OPTIONS.

            8.1 Notice. Options may be exercised only by delivery to the Company
of an exercise agreement in a form approved by the Committee stating the number
of Shares being purchased, the restrictions imposed on the Shares and such
representations and agreements regarding the Optionee's investment intent and
access to information as may be required 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.

            8.2 Payment. Payment for the Shares purchased upon exercise of an
Option may be made (a) in cash or by check; (b) by surrender of shares of Common
Stock of the Company that have been owned by the Optionee for more than six (6)
months (and which 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 were obtained by the
Optionee in the open public market, having a Fair Market Value equal to the
exercise price of the Option; (c) by waiver of compensation due or accrued to
the Optionee for services rendered; (d) provided that a public market for the
Company's stock exists, through a "same day sale" commitment from the Optionee
and a broker-dealer that is a member of the National Association of Securities
Dealers (an "NASD DEALER") whereby the Optionee 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; (e) provided
that a public market for the Company's stock exists, through a "margin"
commitment from the Optionee and a NASD Dealer whereby the Optionee 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.

            8.3 Withholding Taxes. Prior to issuance of the Shares upon exercise
of an Option, the Optionee shall pay or make adequate provision for any federal
or state withholding obligations of the Company, if applicable.

            8.4 Limitations on Exercise. Notwithstanding the exercise periods
set forth in the Grant, exercise of an Option shall always be subject to the
following limitations:

                (a) An Option shall not be exercisable until such time as this
Plan (or, in the case of Options granted pursuant to an amendment increasing the
number of shares that may be issued pursuant to this Plan, such amendment) has
been approved by the stockholders of the Company in accordance with Section 15
hereof.



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            (b) An Option shall not be exercisable unless such exercise is in
compliance with the Securities Act and all applicable state securities laws, as
they are in effect on the date of exercise.

            (c) The Committee may specify a reasonable minimum number of Shares
that may be purchased upon any exercise of an Option, provided that such minimum
number will not prevent the Optionee from exercising the full number of Shares
as to which the Option is then exercisable.

        9. NONTRANSFERABILITY OF OPTIONS. During the lifetime of the Optionee,
an Option shall be exercisable only by the Optionee or by the Optionee's
guardian or legal representative, unless otherwise permitted by the Committee.
No Option may be sold, pledged, assigned, hypothecated, transferred or disposed
of in any manner other than by will or by the laws of descent and distribution.

        10. PRIVILEGES OF STOCK OWNERSHIP. No Optionee shall have any of the
rights of a stockholder with respect to any Shares subject to an Option until
the Option has been validly exercised. No adjustment shall be made for dividends
or distributions or other rights for which the record date is prior to the date
of exercise, except as provided in this Plan. The Company shall provide to each
Optionee a copy of the annual financial statements of the Company, at such time
after the close of each fiscal year of the Company as they are released by the
Company to its stockholders.

        11. ADJUSTMENT OF OPTION SHARES. In the event that the number of
outstanding shares of Common Stock of the Company is changed by a stock
dividend, stock split, reverse stock split, 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 will be made by the Board in the number of Shares available under
this Plan and the number of Shares subject to outstanding Options and the
exercise price per share of such outstanding Options, subject to any required
action by the stockholders of the Company and compliance with applicable
securities laws; provided, however, that no fractional shares shall be issued
upon exercise of any Option and any resulting fractions of a Share shall be
rounded up to the nearest whole Share.

        12. NO OBLIGATION TO CONTINUE AS DIRECTOR. Nothing in this Plan or any
Option granted under this Plan shall confer on any Optionee any right to
continue as a director of the Company.

        13. COMPLIANCE WITH LAWS. The grant of Options and the issuance of
Shares upon exercise of any Options shall be subject to and conditioned upon
compliance with all applicable requirements of law, including without limitation
compliance with the Securities Act, compliance with all other applicable state
securities laws and compliance with the requirements of any stock exchange or
national market system on which the Shares may be listed. The Company shall be
under no obligation to register the Shares with the SEC or to effect compliance
with the registration or qualification requirement of any state securities laws,
stock exchange or national market system.



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        14. ACCELERATION OF OPTIONS. 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 or replaced by the successor corporation,
which assumption will be binding on all Optionees), (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 of the Code
wherein the stockholders of the Company give up all of their equity interests 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), the vesting of all options granted pursuant to
this Plan will accelerate and the options will become exercisable in full prior
to the consummation of such event at such times and on such conditions as the
Committee determines, and if such options are not exercised prior to the
consummation of the corporate transaction, they shall terminate in accordance
with the provisions of this Plan.

        15. AMENDMENT OR TERMINATION OF PLAN. The Committee may at any time
terminate or amend this Plan (but may not terminate or amend the terms of any
outstanding option without the consent of the Optionee); provided, however, that
the Committee shall not, without the approval of the stockholders of the
Company, increase the total number of Shares available under this Plan (except
by operation of the provisions of Sections 4 and 11 above) or change the class
of persons eligible to receive Options. Further, the provisions in Sections 6
and 7 of this Plan shall not be amended more than once every six (6) months,
other than to comport with changes in the Code, the Employee Retirement Income
Security Act or the rules thereunder. In any case, no amendment of this Plan may
adversely affect any then outstanding Options or any unexercised portions
thereof without the written consent of the Optionee.

        16. TERM OF PLAN. Options may be granted pursuant to this Plan from time
to time within a period of ten (10) years from the date this Plan is adopted by
the Board.

        17. CERTAIN DEFINITIONS. As used in this Plan, the following terms shall
have the following meanings:

            17.1 "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 the Option, 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.

            17.2 "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



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Option, each of the corporations other than the last corporation in the unbroken
chain owns stock possessing fifty percent (50%) or more of the total combined
voting power of all classes of stock in one of the other corporations in such
chain.

            17.3 "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.

            17.4 "FAIR MARKET VALUE" shall mean, as of any date, the value of a
share of the Company's Common Stock determined by the Board in its sole
discretion, exercised in good faith; provided, however, that where there is a
public market for the Common Stock, the Fair Market Value per share shall be the
average of the closing bid and asked prices of the Common Stock on the last
trading day prior to the date of determination as reported in The Wall Street
Journal (or, if not so reported, as otherwise reported by the Nasdaq Stock
Market) or, in the event the Common Stock is listed on a stock exchange or on
the Nasdaq National Market, the Fair Market Value per share shall be the closing
price on the exchange or on the Nasdaq National Market on the last trading date
prior to the date of determination as reported in The Wall Street Journal;
provided, however, that notwithstanding the foregoing, with respect to the
Initial Grants that are granted on the Effective Date, the "Fair Market Value"
shall mean the price per share at which shares of the Company's Common Stock are
initially offered for sale to the public by the Company's underwriters in the
initial public offering of the Company's Common Stock pursuant to a registration
statement filed with the SEC under the Securities Act.


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