Document:

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                                                                   EXHIBIT 10.16

February 2, 2000

Mr. Michael Shahbazian
1292 Estate Drive
Los Altos, CA  94024

Dear Mike:

As Dave discussed with you, we are pleased to offer you the position of Senior
Vice President and Chief Financial Officer with Inventa.  You will report to
Dave Lavanty, President and CEO and will be based out of our Redwood Shores
headquarters.  Your responsibility will encompass all financial operations for
the firm.

Your base salary will be $7916.66 which is paid semi-monthly, and is equivalent
to $190,000 when paid over a year.  Salaries are reviewed at least once a year
and are adjusted as needed in relation to individual performance and salaries in
the marketplace.  You will also be eligible to receive a quarterly performance
bonus of 40% of your base salary.  The metrics for payment of the bonus will be
based on 50% Company revenue performance and 50% personal MBO's performance.

Under the terms of the company's Incentive Stock Option Plan, you will also
receive an option to acquire 225,000 shares of Inventa common stock at an
exercise price per share equal to the market value as determined by the Board of
Directors on the next option grant date.  This option will vest 25% on your
first anniversary of employment and ratably every month over the next three
years until fully vested after four years of employment.  You may receive
additional option grants over time as a result of performance and/or added
responsibilities.  All option grants are, of course, subject to approval by the
Inventa Board of Directors.

Additionally, under separate cover, you will receive an employment agreement as
prepared by our attorneys.  This agreement will allow salary and benefit
continuation for 6 months after a "change of control and/or involuntary
termination without cause", event.

You will be entitled to the complete Inventa benefits package, which is outlined
in the enclosed Benefits Summary.  Please feel free to call Michelle Burnham at
650-413-1128 or send e-mail to mburnham@inventa.com if you have any questions or
                               --------------------
would like more information on the benefits.

Upon joining Inventa, you will be required to sign a Confidentiality and
Proprietary Information Agreement as a condition of employment with the company.
Your employment is at-will which means either you or the company can terminate
your employment at any time.  If your employment terminates for any reason, you
shall not be entitled to any payments, benefits, damages, awards or compensation
other than as provided by this offer letter, or as may otherwise be available in
accordance with the Company's established employee plans and policies at the
time of termination.
<PAGE>

Michael Shahbazian
Page 2

The United States government requires all new employees to present evidence of
their identity and legal right to work in this country within three days of the
date they begin work.  The enclosed "Lists of Acceptable Documents" show the
documents you may present to fulfill these requirements.  Please note you must
either 1) present a document from List A or 2) present one document from List B
and one document from List C. You will need to bring appropriate documents with
you the day you report for work.  If you elect to use a U.S. social security
card as proof of employment eligibility, it must be an original card.

If you have any questions regarding this offer please feel free to contact Dave
or myself.  Please note that this offer is contingent upon a successful
completion of a background check based on the information you will provide to us
on the " Release Form for Consumer Reports" (attached).  If this offer is
acceptable to you, please sign and date the original in the spaces provided
below and, if you know it, indicate the date you can begin work.  Please keep
the copy of this letter for your records and return the original to me by
February 4, 2000.

Mike, we are committed to building Inventa into a world-class company.  You will
be a major part of that effort, as well, our success.  This will require
dedication and hard work from all of us.  We feel you would be a valuable
addition to Inventa and look forward to having you as part of our team in
meeting this challenge.

Sincerely,

Elizabeth Campbell
Vice President, Human Resources
Inventa Corporation

Enclosures (3)

SIGNATURE: ______________________________________
DATE: ___________________________________________

STARTING DATE: __________________________________<PAGE>

                                                                   EXHIBIT 10.20

                             [Inventa Letterhead]

August 5, 1998

Elizabeth J. Campbell
3725 El Centro Avenue
Paid Alto, CA 94306

Dear Elizabeth:

As Michael Makishima, Inventa Corporation Controller, discussed in his recent
telephone conversation with you, we are pleased to offer you a position as
Director of Human Resources with Inventa. In this position, you will be based at
Inventa's Santa Clara office and will report to Michael.

Your base salary will be $4,166.67 which is paid semi-monthly and is equivalent
to $100,000 when paid over a year. Salaries are reviewed at least once a year
and are adjusted as needed in relation to individual performance and salaries in
the marketplace. You will also be eligible to receive an annual performance
bonus that is based on company and individual performance. The target bonus
percentage for your position and salary grade level is 25%. In lieu of a 1998
bonus, you shall receive a sign-on bonus of  $10,000, payable on the first pay
period following your start date.  If you leave the company within your first
year of employment, the $10,000 is repayable to the company.

Under the terms of the company's Incentive Stock Option Plan, you will receive
and option to acquire 20,000 shares of Inventa common stock at an exercise price
per share equal to the market value as determined by the Board of Directors on
the next option grant date. This option will vest 25% on your first anniversary
of employment, and ratably every month over the next three years until fully
vested after four years of employment. You may receive additional option grants
over time as a result of performance and/or added responsibilities. All option
grants are, of course, subject to approval by the Inventa Board of Directors.

You will be entitled to the complete Inventa benefits package which is outlined
in the enclosed Benefits Summary. The Inventa 401(k) Plan allows you to defer
paying taxes on up to approximately 19% of your compensation or $10,000 per
year, whichever is less, by investing that amount in one or more of the
investment vehicles provided by the Plan. Inventa also matches 25% on the first
4% of compensation you contribute to the Plan. Please feel free to call me at
408-987-0220, ext. 320 or send e-mail to dsmith@inventa.com if you have any
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questions or would like more information on the benefits.

Upon joining Inventa, you will be required to sign a Confidentiality and
Proprietary Information Agreement as a condition of employment with the company.
Your employment is at will which means either you or the company can terminate
your employment at any time.
<PAGE>

Elizabeth J. Campbell                 [Inventa Letterhead]
Page 2

The United States government requires all new employees to present evidence of
their identity and legal right to work in the this country within three days of
the date they begin work. The enclosed "Lists of Acceptable Documents" show the
documents you may present to fulfill these requirements. Please note you must
either 1) present a document from List A or 2) present one document from List B
and one document from List C. You will need to bring appropriate documents with
you the day you report for work. If you elect to use a U.S. social security card
as proof of employment eligibility, it must be an original card.

If you have any questions regarding this offer please don't hesitate to contact
me. If this offer is acceptable to you, please sign and date the original in the
spaces provided below and return it to me in the enclosed FedEx envelope. The
copy is for your records.

Elizabeth, Inventa management and employees are committed to build Inventa into
a world-class company. Of course, this will require dedication and hard work
from everyone. We feel you would be a valuable addition to Inventa and look
forward to having you as part of the team in meeting this challenge.

Sincerely

/s/ Dixie E. Smith
---------------------

Dixie E. Smith
Acting Human Resources Manager
Inventa Corporation

Enclosures (3)

                    SIGNATURE:__________________________

                    DATE:_______________________________<PAGE>

                                                                   EXHIBIT 10.21

                            [LETTERHEAD OF INVENTA]

July 14, 1997
Michael S. Makishima
949 Exmoor Way
Sunnyvale, CA 94087

Dear Michael:

It was a pleasure to meet with you and I am happy to offer you a position as
Controller with Inventa.

In this position, you will be responsible for the accounting and financial
aspects of the business, managing human resources, and managing information
systems and facilities. You will be based at Inventa's Santa Clara office, and
report to the President. Upon joining the company, you will be required to sign
a Confidentiality and Proprietary Information Agreement as a condition of
employment with Inventa.

Your base starting salary will be $90,000 per year, which will be reviewed based
on your performance at least annually. In addition, you will also be eligible to
receive an annual performance bonus that is based on company and individual
performance -- for your grade level the target bonus percentage is 25% of annual
salary.

You will also receive, under the terms of the company's Incentive Stock Option
Plan, an option to acquire 30,000 shares of Inventa common stock at an exercise
price per share equal to the market value as determined by the Board of
Directors on the next option grant date -- this option will vest fully over four
years of employment with the company. You may also, based on performance and/or
added responsibilities, receive additional option grants over time.

You will further be entitled to the complete Inventa benefits package outlined
on the attached sheets.

This offer of employment expires at 5:00 PM on July 15, 1997 and is contingent
upon your availability to start work at Inventa on or prior to July 21, 1997.

Michael, we think we have something special here at Inventa and plan to build it
into something great. Doing so will require a lot of hard work. I look forward
to having you as part of our team in meeting this challenge.

Sincerely,

/s/ Ashok Santhanam
Ashok Santhanam
Inventa Corporation

I accept the terms of employment as offered in the letter above. I understand
and agree that my employment with Inventa is at will, and that either the
company or I can terminate my employment at any time.

                              /s/Michael S. Makishima  Date:   7/14/97
                              -----------------------          -------
                              Michael S. Makishima

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