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EXHIBIT 10.20

AGREEMENT

    This Agreement ("Agreement") is entered into effective as of December 15,
2000 (the "Effective Date") by and between Preview Systems, Inc., with an office
at 1195 W. Fremont Ave., Suite 2001, Sunnyvale, CA 94087 ("PSI") and Sony
Marketing (Japan), Inc., with an office at 4-10-18 Tanakawa, Minato-ku, Tokyo,
108-0074, Japan ("SMOJ").

Background.

1.SMOJ and PSI have previously entered into a License Agreement effective as of
September 29, 1998 ("Original License Agreement"), which was subsequently
amended by an Amendment No. 1 to License Agreement effective as of June 29, 2000
(the "Amendment").

2.SMOJ has been engaged in promoting and developing the market for the Localized
Software pursuant to the exclusive license rights granted to SMOJ under the
License Agreement (as defined in Section 1.2 below).

3.To assist in developing the market for the Localized Software in Japan, PSI
has committed to paying SMOJ certain market development funds pursuant to a
letter agreement regarding Market Development Funding dated June 30, 2000 (the
"MDF Agreement").

4.The parties have discussed their relationship and have mutually determined
that the relationship set forth in the License Agreement should be terminated.

Agreement.

    In consideration of the mutual promises set forth in this Agreement, the
parties agree as follows:

1.Definitions.

1.1All terms with initial capitals which are not defined in this Agreement shall
have the meaning set forth in the License Agreement.

1.2"License Agreement" shall mean the Original License Agreement, as amended by
the Amendment.

1.3"FY2000" means April 1, 2000 to March 31, 2001.

1.4"FY2001" means April 1, 2001 to March 31, 2002.

1.5"ZipLock DDM System" means PSI's proprietary "ZipLock DDM System" for the
distribution of music.

1.6"Qualifying Customer" means Symantec Japan and any entity receiving a license
from SMOJ to the Localized Software which is in effect as of March 31, 2001.

1.7"Annual License Fee" means any annual license fee (excluding fees for
maintenance and support, consulting services or other services performed by PSI)
received by PSI or PSI's Japanese subsidiary during FY2001 in connection with
licensing a Qualifying Customer to use the ZipLock ESD System or the ZipLock DDM
System in Japan.

1.8"Prorated Annual License Fee" means an Annual License Fee multiplied by a
percentage equal to the percentage of the corresponding annual period which
falls within FY2001 (e.g. if the corresponding annual period commences on
October 1, 2001, so that 6 months of the corresponding annual period falls
within FY2001, the Prorated Annual License Fee would be 50% of the Annual
License Fee).

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1.9"Prorated SMOJ Maintenance Fee" means a maintenance fee received by SMOJ in
connection with the Localized Software (minus any Running Royalty separately
payable to PSI in connection with such maintenance fee pursuant to the License
Agreement) multiplied by a percentage equal to the percentage of the
corresponding maintenance period which falls after March 31, 2001. For example,
if SMOJ receives $10,000 from a customer in Japan to provide maintenance for the
Localized Software during the annual period commencing on October 1, 2000, (i)
SMOJ would owe PSI a Running Royalty of $4,000 (40% of $10,000) pursuant to the
License Agreement, and (ii) since six months (from April 1, 2001 to September
30, 2001) of the twelve-month maintenance period falls after March 31, 2001, the
Prorated SMOJ Maintenance Fee would be 50% of the remaining $6,000, i.e. $3,000.

2.Termination of License Agreement.

2.1Notwithstanding Section 10.1 of the Original License Agreement, the License
Agreement shall terminate on March 31, 2001.

2.2Prior to March 31, 2001, notwithstanding anything to the contrary in the
License Agreement, revenues received by PSI pursuant to any agreements entered
into by PSI and Matsushita Electric Industrial Co. ("MEI"), NTT Communications
("NTT") or Label Gate will not be shared with SMOJ. After March 31, 2001, NTT,
MEI and Label Gate will not be deemed to be Qualifying Customers.

2.3Revenues received by SMOJ from customers of Localized Software in Japan
pursuant to agreements entered into by SMOJ and such customers prior to March
31, 2001 will be subject to the payment of royalties to PSI as set forth in
Section 4.2 of the License Agreement.

2.4Sections 10.4 and 10.5 of the Original License Agreement shall remain in
effect and shall operate after March 31, 2001, in the same manner as such
sections would have remained in effect and operated if the Original License
Agreement had expired or been terminated as set forth in Sections 10.1, 10.2 or
10.3 of the Original License Agreement; provided, that the provisions of the
second and third sentences of Section 10.4 of the Original License Agreement
(dealing with the return of copies of Localized Software and Confidential
Information) shall not be implemented if, as of March 31, 2001, the parties have
entered into and are bound by a new agreement, setting forth the details of a
new relationship between the parties, which provides that such copies of
Localized Software and Confidential Information should be retained by SMOJ or
PSI, as applicable.

3.Payments.

3.1PSI shall complete its payment to SMOJ of $400,000 in market development
funds during FY2000, as set forth in the MDF Agreement.

3.2SMOJ shall honor the guarantee set forth in Section 2 of the Amendment, and
shall pay PSI at least $800,000 (the Minimum Running Royalty during FY2000,
pursuant to Section 2 of the Amendment) prior to the end of FY2000.

3.3In consideration of SMOJ's losing the exclusive rights set forth in the
License Agreement at the end of FY2000, PSI will pay SMOJ $460,000 on or prior
to the end of FY2000.

3.43.7 Within sixty (60) days after the end of each calendar quarter during
FY2001, PSI will pay to SMOJ sixty percent (60%) of all Prorated Annual License
Fees received by PSI during such calendar quarter.

3.83.9 Within sixty (60) days after the end of FY2000, SMOJ will pay to PSI all
Prorated SMOJ Maintenance Fees.

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4.General Provisions.

4.1Notices sent by one party to the other pursuant to this Agreement shall
comply with the requirements set forth in Section 11.1 of the Original License
Agreement; provided, that such notices shall be sent to the parties' respective
addresses set forth above, and shall be addressed to Mr. Yoshimitsu Nakayama (in
the case of notices for SMOJ) or Mr. Vincent Pluvinage (in the case of notices
for PSI).

4.24.3 This Agreement may not be assigned by either party without the written
consent of the other party; provided, that such consent shall not be required in
the case of an assignment to an acquiror or merger partner of the assigning
party. Subject to the preceding sentence, the rights and liabilities of the
parties under this Agreement will bind, and inure to the benefit of, the parties
and their successors and assigns. Any attempted assignment or other transfer
other than in accordance with this Section 4.2 shall be null and void.

4.4Sections 11.3, 11.5, 11.6, 11.7, 11.8, 11.9, 11.10, 11.12, 11.13 and 11.14 of
the Original License Agreement are hereby incorporated into this Agreement by
reference.

4.6This Agreement constitutes the entire agreement between the parties
concerning its subject matter, and supersedes all prior or contemporaneous
representations, discussions, proposals, negotiations, conditions, agreements
and communications, whether oral or written, between the parties relating to the
subject matter of this Agreement and all past courses of dealing or industry
custom. No amendment or modification of any provision of this Agreement shall be
effective unless in writing and signed by a duly authorized signatory of each
party.

AGREED AND ACCEPTED, EFFECTIVE AS OF THE EFFECTIVE DATE:

 
   
SONY MARKETING (JAPAN), INC.   REVIEW SYSTEMS, INC.
By:

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By:

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Name:

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Name:

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Title:

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Title:

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AGREEMENT