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                                                                   EXHIBIT 10.20



                           LOAN MODIFICATION AGREEMENT

     This Loan Modification Agreement is entered into as of January 9, 2002 by
and between Packeteer, Inc. ("Borrower") and Silicon Valley Bank ("Bank").

1.   DESCRIPTION OF EXISTING INDEBTEDNESS: Among other indebtedness which may be
owing by Borrower to Bank, Borrower is indebted to Bank pursuant to, among other
documents, a Loan and Security Agreement, dated January 19, 1999, as may be
amended from time to time, (the "Domestic Loan Agreement") and an Export-Import
Bank Loan and Security Agreement, dated January 19, 1999, as may be amended from
time to time, (the "Exim Loan Agreement"). The Domestic Loan Agreement provided
for, among other things, a Committed Revolving Line in the original principal
amount of One Million Five Hundred Thousand Dollars ($1,500,000) and the Exim
Loan Agreement provided for, among other things, an Exim Committed Line in the
original principal amount of One Million Five Hundred Thousand Dollars
($1,500,000). In connection with the Exim Loan Agreement, Borrower will execute
concurrently herewith, a Borrower Agreement. The Domestic Loan Agreement has
been modified pursuant to a Loan Modification Agreement dated January 9, 2001,
pursuant to which, among other things, the original principal amount of the
Committed Revolving Line was increased to Five Million Dollars ($5,000,000). The
Exim Loan Agreement has been modified pursuant to a Loan Modification Agreement
dated January 9, 2001, pursuant to which, among other things, the original
principal amount of the Exim Committed Line was increased to Five Million
Dollars ($5,000,000). Defined terms used but not otherwise defined herein shall
have the same meanings as in the Loan Agreements.

Hereinafter, all indebtedness owing by Borrower to Bank shall be referred to as
the "Indebtedness."

2.   DESCRIPTION OF COLLATERAL AND GUARANTIES. Repayment of the Indebtedness is
secured by the Collateral as described in the Loan Agreement and an Intellectual
Property Security Agreement dated January 19, 1999. Additionally, repayment of
the Exim Committed Line is guaranteed by the Export Import Bank of the United
States ("EXIM").

Hereinafter, the above-described security documents and guaranties, together
with all other documents securing repayment of the Indebtedness shall be
referred to as the "Security Documents". Hereinafter, the Security Documents,
together with all other documents evidencing or securing the Indebtedness shall
be referred to as the "Existing Loan Documents".

3.   DESCRIPTION OF CHANGE IN TERMS.

     A.   Modification(s) to Domestic Loan Agreement.

          1.   Subsection (ii) under Section 6.7 entitled "Financial Covenants"
               is hereby amended to read:

               (II) PRO-FORMA PROFITABILITY. Borrower will have a minimum
                    pro-forma profit of $500,000 per quarter, except that
                    Borrower may suffer losses not to exceed $2,000,000 for the
                    quarter ending December 31, 2001; $1,500,000 for the quarter
                    ending March 31, 2002; and $1,000,000 for the quarter ending
                    June 30, 2002. Notwithstanding the foregoing, for the
                    quarter ending September 30, 2002 Borrower shall achieve at
                    least $100,000 in Pro-forma profit. For calculation
                    purposes, Pro-forma is defined as net income excluding
                    non-cash acquisition related and stock based compensation
                    charges.

          2.   Sub-letter (d) of Section 6.2 entitled "Financial Statements,
               Reports, Certificates" is hereby amended to read as follows:

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               Borrower has the right to audit Borrower's Collateral at
               Borrower's expense, but the audits will be conducted no more
               often than every 6 months unless an Event of Default has occurred
               and is continuing.

          3.   The following term under Section 13.1 entitled "Definitions" is
               hereby amended to read as follows:

               "Revolving Maturity Date" is May 31, 2003.

     B.   Modification(s) to Exim Loan Agreement.

          1.   Subsection (ii) Section 6.10 entitled "Financial Covenants" is
               hereby amended to read:

               (ii) Pro-forma Profitability. Borrower will have a minimum
                    pro-forma profit of $500,000 per quarter, except that
                    Borrower may suffer losses not to exceed $2,000,000 for the
                    quarter ending December 31, 2001; $1,500,000 for the quarter
                    ending March 31, 2002; and $1,000,000 for the quarter ending
                    June 30, 2002. Notwithstanding the foregoing, for the
                    quarter ending September 30, 2002 Borrower shall achieve at
                    least $100,000 in Pro-forma profit. For calculation
                    purposes, Pro-forma is defined as net income excluding
                    non-cash acquisition related and stock based compensation
                    charges.

          2.   Sub-letter (d) of Section 6.2 entitled "Financial Statements,
               Reports, Certificates" is hereby amended to read as follows:

               Borrower has the right to audit Borrower's Collateral at
               Borrower's expense, but the audits will be conducted no more
               often than every 6 months unless an Event of Default has occurred
               and is continuing.

          3.   The following terms under Section 13.1 entitled "Definitions" are
               hereby amended to read as follows:

               "Exim Maturity Date" is May 31, 2003.

               The following is incorporated under the defined term "Exim
               Eligible Foreign Accounts"

               (o)   Accounts for an account debtor, including Affiliates, whose
               total obligations to Borrower exceed 25% of all Accounts, for the
               amounts that exceed that percentage.

4.   CONSISTENT CHANGES. The Existing Loan Documents are hereby amended wherever
necessary to reflect the changes described above.

5.   PAYMENT OF FEES. Borrower shall pay to Bank a fee in the amount of
Seventeen Thousand Seven Hundred Eight Dollars ($17,708) for Committed Revolving
Line and Thirty Nine Thousand Six Hundred Sixty Seven Dollars ($39,667) for the
Exim Committed Line (collectively the "Loan Fee"), plus all out-of-pocket
expenses.

6.   NO DEFENSES OF BORROWER. Borrower (and each guarantor and pledgor signing
below) agrees that, as of the date hereof, it has no defenses against the
obligations to pay any amounts under the Indebtedness.

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7.   CONTINUING VALIDITY. Borrower (and each guarantor and pledgor signing
below) understands and agrees that in modifying the existing Indebtedness, Bank
is relying upon Borrower's representations, warranties, and agreements, as set
forth in the Existing Loan Documents. Except as expressly modified pursuant to
this Loan Modification Agreement, the terms of the Existing Loan Documents
remain unchanged and in full force and effect. Bank's agreement to modifications
to the existing Indebtedness pursuant to this Loan Modification Agreement in no
way shall obligate Bank to make any future modifications to the Indebtedness.
Nothing in this Loan Modification Agreement shall constitute a satisfaction of
the Indebtedness. It is the intention of Bank and Borrower to retain as liable
parties all makers and endorsers of Existing Loan Documents, unless the party is
expressly released by Bank in writing. No maker, endorser, or guarantor will be
released by virtue of this Loan Modification Agreement. The terms of this
paragraph apply not only to this Loan Modification Agreement, but also to all
subsequent loan modification agreements.

8.   CONDITIONS. The effectiveness of this Loan Modification Agreement is
conditioned upon Borrower's payment of the Loan Fee.

     This Loan Modification Agreement is executed as of the date first written
above.

BORROWER:                               BANK:

PACKETEER, INC.                         SILICON VALLEY BANK

By:                                     By:
   ---------------------------------       -------------------------------------
Name:                                   Name:
     -------------------------------         -----------------------------------
Title:                                  Title:
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