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                                                                   EXHIBIT 10.19

                           LOAN MODIFICATION AGREEMENT

     This Loan Modification Agreement is entered into as of January 9, 2001 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. 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 (a) under Section 2.1.1 entitled "Revolving Advances"
               is hereby amended to read as follows:

               (a)  Bank will make Advances not exceeding (i) the lesser of (A)
                    the Committed Revolving Line minus the Cash Management
                    Services Sublimit or (B) the Borrowing Base, minus (ii) the
                    amount of all outstanding Letters of Credit (including drawn
                    but unreimbursed Letters of Credit). Amounts borrowed under
                    this Section may be repaid and reborrowed during the term of
                    this Agreement.


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          2.   Section 2.1.3 entitled "Letters of Credit Sublimit" is hereby
               incorporated to read as follows:

               Bank will issue or have issued Letters of Credit for Borrower's
               account not exceeding (i) the lesser of the Committed Revolving
               Line or the Borrowing Base minus (ii) the outstanding principal
               balance of the Advances, minus the Cash Management Services
               Sublimit, but the face amount of outstanding Letters of Credit
               (including drawn but unreimbursed Letters of Credit) may not
               exceed $2,500,000. Each Letter of Credit will expire no later
               than 180 days after the Revolving Maturity Date provided
               Borrower's Letter of Credit reimbursement obligation is secured
               by cash on terms acceptable to Bank at any time after the
               Revolving Maturity Date if the term of this Agreement is not
               extended by Bank.

          3.   Section 2.2 entitled "Overadvances" if Borrower's Obligation
               under Section 2.1.1 and 2.1.3 exceed the lesser of either (i) the
               Committed Revolving Line minus the Cash Management Services
               Sublimit or (ii) the Borrowing Base, Borrower must immediately
               pay Bank the excess.

          4.   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 for each quarter. For
                    calculation purposes, Pro-forma is defined as net income
                    excluding acquisition related and stock based compensation
                    charges.

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

               "COMMITTED REVOLVING LINE" is an Advance of up to $5,000,000.

               "LETTER OF CREDIT SUBLIMIT" is defined in Section 2.1.3

               "REVOLVING MATURITY DATE" is January 10, 2002.

     B.   Modification(s) to Exim Loan Agreement.

          1.   Sub-letter (a) of Section 2.1.1 entitled "Revolving Advances" is
               hereby amended in part to provide that Borrowing Base shall now
               mean an amount equal to ninety percent (90%) of Exim Eligible
               Foreign Accounts.


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

               (ii) PROFITABILITY. Borrower will have a minimum net profit of
                    $500,000 for each quarter. PRO-FORMA PROFITABILITY. Borrower
                    will have a minimum pro-forma profit of $500,000 for each
                    quarter. For calculation purposes, Pro-forma is defined as
                    net income excluding acquisition related and stock based
                    compensation charges.

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

               "EXIM COMMITTED LINE" is an Advance of up to $5,000,000.

               "EXIM MATURITY DATE" is January 10, 2002.

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 Twelve
Thousand Five Hundred Dollars ($12,500) for the Committed Revolving Line (the
"Domestic Loan Fee") plus a fee in the amount of Twenty Eight Thousand Dollars
($28,000) for the Exim Committed Line (the "Exim Loan Fee") plus all
out-of-pocket expenses. Additionally, Borrower shall pay any Exim Bank Expenses
incurred in connection with the Exim Guarantee. Notwithstanding the foregoing,
any attorney fees or expenses incurred in connection with this Agreement shall
be capped at $5,000 for each credit facility.

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.

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


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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:

     1)   Borrower's payment of the Domestic Loan Fee, the Exim Loan Fee and any
          Exim fees incurred in connection with this Agreement; and

     2)   Bank's receipt of a fully executed Borrower Agreement together with
          all Annex's and/or attachments thereto.

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

BORROWER:                               BANK:

PACKETEER, INC.                         SILICON VALLEY BANK


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