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EXHIBIT 10.20

April 23, 1999

Mr. Barry Briggs
93 Cameron Drive
Marlboro, MA  01752

Dear Barry,

I am delighted to offer you the position of Chief Technology Officer of
Interleaf, Inc. Our company is at a very important juncture. Tremendous
opportunities for success are within our sights but there is work to be done.
Your credentials and energy are very impressive. I am sure that you will have a
positive influence on our results.

THE POSITION
The Chief Technology Officer (CTO) position is one of the most important officer
level positions in our company. You will be responsible for development of new
technology directions, assessment of current technology products and development
of our long-term technology/solution strategy. As a direct report to the Chief
Executive Officer, you will also be asked to actively participate in the
development of our overall business strategy, interface directly with major
customers as well as the Board of Directors and participate on the senior
management team.

COMPENSATION PACKAGE
The base salary for the Chief Technology Officer position is $5,800 per pay
period (26 per year), and you will participate in an annual incentive
compensation pool with total on target annual earnings of $200,000.

In addition to your base and bonus compensation, you will receive a signing
bonus of $20,000 to be utilized for the purchase of Interleaf stock by yourself
in the open market during your first ten (10) days of employment. You are
responsible for any taxes on this bonus. This stock will be yours to hold and
keep, but it is expected that you will not sell prior to a liquidity event, the
passage of two years or your departure from the company. We believe that your
becoming an immediate equity holder will provide you a stronger leadership
stance and ease communication with external constituents.

Your incentive compensation program is designed to reward you for meeting our
annual performance goals. The incentive compensation program will provide you
with a bonus pool of $50,000 upon achievement of Interleaf's annual business
plan, revenue and profit targets, and an escalation bonus should we exceed the
target.. The specific calculation of bonus payment is detailed in the attached
Senior Managers Compensation Plan.

EQUITY PARTICIPATION

In addition to your signing bonus, I am delighted to offer you 75,000 stock
options. These options will be granted at the next regularly scheduled Board
meeting, with an exercise price equal to fair market value of the Common Stock
on the date of grant, and will vest over four years, with 6.25% vesting each
quarter from the date of grant. As we discussed, I am fully committed to having
you achieve your long-term compensation goals.

Please note that this letter does not constitute an employment agreement. In the
unlikely circumstance that you are terminated without cause, the company will
pay you 13 equal payments over six (6) months in an amount equal to six (6)
months base salary, based on your annual base salary at the highest rate in
effect during the 12-month period immediately preceding the effective date of
termination.

BENEFITS PACKAGE
Your compensation will also include participate in our standard corporate
benefits program, a summary of which is attached.


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I am very much looking forward to your joining our team. I know that you will do
an outstanding job in this critical role. Your expected start date is May 1,
1999. Please indicate your acceptance and agreement with the terms of this
employment offer by signing below. Again, we look forward to your joining the
team.

Sincerely,


/s/ Jaime W. Ellertson
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Jaime W. Ellertson
President and Chief Executive Officer


Accepted:


/s/ Barry Briggs
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Barry Briggs                                         Date