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                                                                    EXHIBIT 10.8

IT IS UNLAWFUL TO CONSUMMATE A SALE OR TRANSFER OF THIS SECURITY OR ANY INTEREST
THEREIN, OR TO RECEIVE ANY CONSIDERATION THEREFOR, WITHOUT THE PRIOR WRITTEN
CONSENT OF THE COMMISSIONER OF CORPORATIONS OF THE STATE OF CALIFORNIA, EXCEPT
AS PERMITTED IN THE COMMISSIONER'S RULES.

THE SECURITY REPRESENTED BY THIS CERTIFICATE HAS BEEN ACQUIRED FOR INVESTMENT
AND NOT WITH A VIEW TO, OR IN CONNECTION WITH, THE SALE OR DISTRIBUTION THEREOF.
NO SUCH SALE OR DISPOSITION MAY BE EFFECTED WITHOUT AN EFFECTIVE REGISTRATION
STATEMENT RELATED THERETO OR AN OPINION OF COUNSEL SATISFACTORY TO THE COMPANY
THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE SECURITIES ACT OF 1933.

                            Stock Option Agreement
                            ----------------------

Inventa Corporation, a California Corporation (the "Company"), hereby grants to
________________ (the "Optionee") an Option to purchase a total of
________shares (the "Shares") of Common Stock, at the price determined as
provided herein, and in all respects subject to the terms, definitions and
provisions of the 1993 Stock Option Plan (the "Plan") adopted by the Company
which is incorporated herein by reference. The terms defined in the Plan shall
have the same defined meanings herein.

1)   Nature of the Option
     If Optionee is an Employee of the Company, this Option is intended to
     qualify as an Incentive Stock Option as defined in Section 422A of the
     Internal Revenue Code of 1986, as amended (the "Code"). If Optionee is a
     Consultant of the Company, this Option is a nonstatutory option and is not
     intended to qualify for any special tax benefits to the Optionee.

2)   Exercise Price
     The exercise price is ______for each share of Common Stock, which price is
     not less than the fair market value per share of Common Stock on the date
     of grant, as determined by the Board.

3)   Exercise of Option
     This Option shall be exercisable during its term in accordance with the
     provisions of Section 9 of the Plan as follows:

(i)  Right to Exercise
     (a) Subject to Subsection 3 (i) (b) and (c) below, 25% of the total number
     of shares subject to this Option shall be exercisable on ________and an
     additional 2.0833% of the total number of shares shall be exercisable
     monthly until all of such shares are exercisable. In no event shall this
     Option provide for vesting at a rate of less than 20% per year over five
     years from the date of grant of this Option.

     (b)  This Option may not be exercised for a fraction of a Share.

     (c)  In the event of Optionee's death, disability or other termination of
     employment, the exercisability of the Option is governed by Sections 7, 8
     and 9 below.

(ii) Method of Exercise
     This Option shall be exercisable by written notice which shall state the
     election to exercise the Option, the number of Shares in respect of which
     the Option is being exercised, and such other representations and
     agreements as to the holder's investment intent with respect to such shares
     of Common Stock as may be required by the Company pursuant to the
     provisions of the Plan. Such written notice shall be signed by Optionee and
     shall be delivered in person or by certified mail to the President,
     Secretary or Chief Financial Officer of the Company. The written notice
     shall be accompanied by payment of the exercise price. This Option shall be
     deemed to be exercised upon receipt by the Company of such written notice
     accompanied by the exercise price.

     No shares will be issued pursuant to the exercise of an Option unless such
     issuance and such exercise shall comply with all relevant provisions of law
     and the requirements of any stock exchange upon which the Shares may then
     be listed. Assuming such compliance, the Shares shall be considered
     transferred to the Optionee on the date on which the Option is exercised
     with respect to such Shares.

4)   Investment Representations; Restrictions on Transfer
(i)  By receipt of this Option, by its execution and by its exercise in whole or
     in part, Optionee represents to the Company the following:

     (a)  Optionee understands that this Option and any shares purchased upon
     its exercise are securities, the issuance of which requires compliance with
     federal and state securities laws.

     (b)  Optionee is aware of the Company's business affairs and financial
     condition and has acquired sufficient information about the Company to
     reach an informed and knowledgeable decision to acquire the securities.
     Optionee is acquiring these securities for investment for Optionee's own
     account only and not with a view to, or for resale in connection with, any
     "distribution" thereof within the meaning of the Securities Act of 1933, as
     amended (the "Securities Act).

     (c)  Optionee acknowledges and understands that the securities constitute
     "restricted securities" under the Securities Act and must be held
     indefinitely unless they are subsequently registered under the Securities
     Act or an exemption from such registration is unavailable. Optionee further
     acknowledges and understands that the Company is under no obligation to
     register the securities. Optionee understands that the certificate
     evidencing the securities will be imprinted with a legend which prohibits
     the transfer of the securities unless they are registered or such
     registration is not required in the opinion of counsel satisfactory to the
     Company, a legend prohibiting their transfer without consent of the
     Commissioner of Corporations of the State of California and any other
     legend required under applicable state securities laws.

     (d)  Optionee is familiar with the provisions of Rule 701 and Rule 144,
     each promulgated under the Securities Act, which, in substance, permit
     limited public resale of "restricted securities" acquired, directly or
     indirectly, from the issuer thereof, in a nonpublic offering subject to the
     satisfaction of certain conditions. Rule 701 provides that if the issuer
     qualifies under Rule 701 at the time of exercise of the Option by the
     Optionee, such exercise will be exempt from registration under the
     Securities Act. In the event the Company later becomes subject to the
     reporting requirements of Section 13 or 15 (d) of the Securities Exchange
     Act of 1934, ninety (90) days thereafter the securities exempt under Rule
     701 may be resold, subject to the satisfaction of certain of the conditions
     specified by Rule 144, including among other things: (1) the sale being
     made through a broker in an unsolicited "broker's transaction" or in
     transactions directly with a market maker (as said term is defined under
     the Securities Exchange Act of 1934); and, in the case of an affiliate, (2)
     the availability of certain public information about the Company, and the
     amount of securities being sold during any three month period not exceeding
     the limitations specified in Rule 144 (e), if applicable. Notwithstanding
     this paragraph 4 (i) (d), the Optionee acknowledges and agrees to the
     restrictions set forth in paragraph 4 (ii).

     (e)  In the event that the Company does not qualify under Rule 701 at the
     time of exercise of the Option, then the securities may be resold in
     certain limited circumstances subject to the provisions of Rule 144, which
     requires among other things: (1) the availability of certain public
     information about the Company; (2) the resale occurring not less than two
     years after the party has purchased, and made full payment for, within the
     meaning of Rule 144, the securities to be sold; and (3) in the case of an
     affiliate, or of a nonaffiliate who has held the securities less than three
     years, the sale being made through a broker in an unsolicited "broker's
     transaction" or in transactions directly with a market maker (as said term
     is defined under the Securities Exchange Act of 1934) and the amount of
     securities being sold during any three month period not exceeding the
     specified limitations stated therein, if applicable.

(ii) Optionee agrees, in connection with the Company's initial underwritten
     public offering of the Company's securities, (1) not to sell, make short
     sale of, loan, grant any options for the purchase of, or otherwise dispose
     of any shares of Common Stock of the Company held by Optionee (other than
     those shares included in the registration) without the prior written
     consent of the Company or the underwriters managing such initial
     underwritten public offering of the Company's securities for one hundred
     eighty (180) days from the effective date of such registration, and (2)
     further agrees to execute any agreement reflecting (1) above as may be
     requested by the underwriters at the time of the public offering.

5)   Method of Payment
     Payment of the purchase price shall be made by cash or check.

6)   Restrictions on Exercise
     This Option may not be exercised until such time as the Plan has been
     approved by the shareholders of the Company, or if the issuance of such
     Shares upon such exercise or the method of payment of consideration for
     such shares would constitute a violation of any applicable federal or state
     securities or other law or regulation, including any rule under Part 207 of
     Title 12 of the Code of Federal Regulations (Regulation "G") as promulgated
     by the Federal Reserve Board. As a condition to the exercise of this
     Option, the Company may require Optionee to make any representation and
     warranty to the Company as may be required by any applicable law or
     regulation.

7)   Termination of Status as an Employee or Consultant
     If Optionee is an Employee and ceases to serve as an Employee or if
     Optionee is a Consultant and ceases to serve as a Consultant, then Optionee
     may, but only within ninety (90) days after the date he ceases to be an
     Employee or Consultant (as the case may be), exercise this Option to the
     extent that he was entitled to exercise it at the date of such termination.
     To the extent that Optionee was not entitled to exercise this Option within
     the time specified herein, this Option shall terminate.

8.)  Disability of Optionee
     Notwithstanding the provisions of section 7 above, if Optionee is unable to
     continue his employment or consulting relationship with the Company as a
     result of his permanent and total disability (as defined in Section 22 (e)
     (3) of the Code), he may,
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     but only within twelve (12) months from the date of termination of
     employment or consulting relationship, exercise this Option to the extent
     he was entitled to exercise it at the date of such termination. To the
     extent that he was not entitled to exercise this Option at the date of
     termination, or if he does not exercise such Option (which he was entitled
     to exercise) within the time specified herein, this Option shall terminate.

9.)  Death of Optionee
     In the event of the death of the Optionee:

(i)  during the term of this Option and while an Employee or Consultant of the
     Company and having been in Continuous Status as an Employee or Consultant
     since the date of grant of this Option, this Option may be exercised, at
     any time within twelve (12) months following the date of death, by
     Optionee's estate or by a person who acquired the right to exercise the
     Option by bequest or inheritance, but only to the extent of the right to
     exercise that would have accrued had Optionee continued living and remained
     in Continuous Status as an Employee or Consultant twelve (12) months after
     the date of death; or

(ii) within ninety (90) days after the termination of Optionee's Continuous
     Status as an Employee or Consultant, this Option may be exercised, at any
     time within twelve (12) months following the date of death, by Optionee's
     estate or by a person who acquired the right to exercise this Option by
     bequest or inheritance, but only to the extent of the right to exercise
     that had accrued at the date of termination.

10)  Non-Transferability of Option
     This Option may not be transferred in any manner otherwise than by will or
     by the laws of descent or distribution and may be exercised during the
     lifetime of Optionee only by Optionee. The terms of this Option shall be
     binding upon the executors, administrators, heirs, successors and assigns
     of Optionee.

11)  Term of Option
     Notwithstanding Section 9, this Option may not be exercised more than ten
     (10) years from the date of grant of this Option, and may be exercised
     during such term only in accordance with the Plan and the terms of this
     Option.

12)  Early Disposition of Stock
     If Optionee is an Employee subject to taxation of income in the United
     States, Optionee understands that if he disposes of any Shares received
     under this Option within two (2) years after the date of this Agreement or
     within one (1) year after such Shares were transferred to him, he will be
     treated for federal income tax purposes as having received ordinary income
     at the time of such disposition in an amount generally measured by the
     difference between the exercise price and the lower of the fair market
     value of the Shares at the date of exercise or the fair market value of the
     Shares at the date of disposition. The amount of such ordinary income may
     be measured differently if Optionee is an officer, director or 10%
     shareholder of the Company, or if the Shares were subject to a substantial
     risk of forfeiture at the time they were transferred to Optionee. Optionee
                                                                       --------
     hereby agrees to notify the Company in writing within 30 days after the
     -----------------------------------------------------------------------
     date of any such disposition. Optionee understands that if he disposes of
     ----------------------------
     such Shares at any time after the expiration of such two-year and one-year
     holding periods, any gain on such sale will be taxed as long term capital
     gain.

13)  Taxation Upon Exercise of Option
     If Optionee is a Consultant, he understands that, upon exercise of this
     Option, he will recognize income for United States tax purposes in an
     amount equal to the excess of the then fair market value of the Shares over
     exercise price. The Company will be required to withhold tax from
     Optionee's current compensation with respect to such income; to the extent
     that Optionee's current compensation is insufficient to satisfy the
     withholding tax liability, the Company may require the Optionee to make a
     cash payment to cover such liability as a condition of exercise of this
     Option. Upon a resale of such shares by the Optionee, any difference
     between the sale price and the fair market value of the shares on the date
     of exercise of the Option will be treated as capital gain or loss.

14)  Miscellaneous
     The recipient of this Option acknowledges that the Company has no
     additional obligation to issue or sell securities to the Optionee.

Date of Grant:                December 17, 1997
Inventa Corporation

By:____________________________________________________________________________

Title:                        Chairman

OPTIONEE ACKNOWLEDGES AND AGREES THAT THE VESTING OF SHARES PURSUANT TO SECTION
3 HEREOF IS EARNED ONLY BY CONTINUING SERVICE AS AN EMPLOYEE OR CONSULTANT AT
THE WILL OF THE COMPANY (NOT THROUGH THE ACT OF BEING HIRED, BEING GRANTED THIS
OPTION OR ACQUIRING SHARES HEREUNDER). OPTIONEE FURTHER ACKNOWLEDGES AND AGREES
THAT THIS OPTION, THE COMPANY'S PLAN WHICH IS INCORPORATED HEREIN BY REFERENCE,
THE TRANSACTIONS CONTEMPLATED HEREUNDER AND THE VESTING SCHEDULE SET FORTH
HEREIN DO NOT CONSTITUTE AN EXPRESS OR IMPLIED PROMISE OF CONTINUED ENGAGEMENT
AS AN EMPLOYEE OR CONSULTANT FOR THE VESTING PERIOD, FOR ANY PERIOD, OR AT ALL,
AND SHALL NOT INTERFERE WITH OPTIONEE'S RIGHT OR THE COMPANY'S RIGHT TO
TERMINATE OPTIONEE'S EMPLOYMENT OR CONSULTING RELATIONSHIP AT ANY TIME, WITH OR
WITHOUT CAUSE.

Optionee acknowledges receipt of a copy of the Plan, a copy of which is annexed
hereto, and represents that Optionee is familiar with the terms and provisions
thereof, and hereby accepts this Option subject to all of the terms and
provisions thereof.  Optionee hereby agrees to accept as binding, conclusive and
final all decisions or interpretations of the Board or of the Committee upon any
questions arising under the Plan.


Dated:_________________________________________________________________________

Optionee:______________________________________________________________________


Residence Address:_____________________________________________________________

_______________________________________________________________________________

_______________________________________________________________________________

Social Security No. ___________________________________________________________
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                                   EXHIBIT A
                                   ---------
                              NOTICE OF EXERCISE
                              ------------------
                         INCENTIVE STOCK OPTION (ISO)
                         ----------------------------


TO:

FROM:

DATE:

RE:            Exercise of Stock Option

     I hereby exercise my option to purchase_________________________shares of
Common Stock at $______________per share (total exercise price of
$__________________, effective today's date. This notice is given in accordance
with the terms of my Stock Option Agreement dated ________________,19_________.
The option price and vested amount is in accordance with Sections 2 and 3 of the
Stock Option Agreement.

     Attached is a check payable to_______________________________________for
the total exercise price of the shares being purchased. The undersigned confirms
the representations made In Section 4 of the Stock Option Agreement.

     Please prepare the stock certificate in the following names(s):

            __________________________________________________

            __________________________________________________

            __________________________________________________


     (If the stock is to be registered in a name other than your name, please so
advise the Company. The Stock Option Agreement requires the Company's approval
for registration in a name other than your name and requires certain agreements
from any joint owner.)


                                 Sincerely,

                                 __________________________________________
                                                (Signature)


                                 __________________________________________
                                            (Print or Type Name)

Letter and consideration received
On _______________, 19______

By:_________________________