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                                                                   EXHIBIT 10.53


                                 PROMISSORY NOTE

LOAN AMOUNT:  $300,000                                     CUPERTINO, CALIFORNIA
INTEREST RATE:  4.9%                                                MAY 15, 1999

            FOR VALUE RECEIVED, the undersigned, KEITH ROBINSON ("BORROWER"),
residing at 156 Oak Hill Way, Los Gatos, California (the "Property"), hereby
promises to pay to the order of SYMANTEC CORPORATION, a Delaware corporation
("LENDER"), at its offices at 10201 Torre Ave., Cupertino, California, or at
such other place or to such other party as LENDER or the holder of this Note may
designate by written notice to BORROWER, in lawful money of the United States of
America, the principal sum of three hundred thousand dollars ($300,000) with
interest thereon to be paid as set forth below.

            1. Purpose of Loan. The purpose of the loan evidenced by this Note
is to provide money for the improvement by BORROWER of the Property.

            2. Interest. Interest at a rate of 4.9% per annum will accrue on any
unpaid principal until the principal is paid in full. Interest shall be payable
in month installments of $1,225, the first such payment being due on June 15,
1999, and then on the fifteenth of each month thereafter, provided, however,
that if any such day is not a Business Day then on the next succeeding Business
Day. As used in this Note the term "Business Day" shall mean any day other than
a Saturday, Sunday or a legal holiday observed by employees of the State of
California.

            3. Principal. The entire principal balance and any accrued interest
shall be due and payable on June 15, 2000.

            4. Prepayment. BORROWER may prepay all or any portion of the loan
evidenced by this Note at any time without penalty, fee or acceleration of the
due date of this Note.

            5. Security. Payment of this Note shall be secured by a deed of
trust (the "Deed of Trust"), given by BORROWER and JANICE D. ROBINSON, as
trustor (collectively), for the benefit of LENDER, as beneficiary, encumbering
the Property. As a condition precedent to LENDER'S obligation to make the loan
evidenced by this Note, BORROWER shall provide to LENDER such information as
LENDER may reasonably require to ensure that the Deed of Trust will provide
adequate security for the loan. Such information shall include, but shall not be
limited to, a recent appraisal of the Property, an updated preliminary title
report on the Property, and information regarding the amounts and terms of any
other liens encumbering the Property. In the event that LENDER determines in its
reasonable discretion that the Deed of Trust will not provide adequate security
for the loan, BORROWER shall provide such additional security as LENDER may
reasonably require, or LENDER shall not be obligated to make the loan.

            6. Acceleration of Due Date. The entire unpaid principal balance of
this Note and any accrued interest thereon shall, at the election of LENDER,
become immediately due and payable upon the occurrence of any of the following
(an "Event of Default"), irrespective of the payment schedules set forth above:

            (a) Any failure on the part of BORROWER to make any payment under
this Note when the same is due;

            (b) Any failure on the part of BORROWER to perform or observe any of
his obligations under this Note or the Deed of Trust or any other deed of trust,
mortgage or security instrument which secures this Note or encumbers the
Property as and when performance is due;


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            (c) On such date thirty days after BORROWER'S employment
relationship with LENDER or any wholly owned subsidiary of LENDER is terminated
for any reason;

            (d) If BORROWER shall sell, transfer, convey or further encumber the
Property or any part thereof, or any interest therein, or shall be divested of
the title or any interest therein, either by any transfer, conveyance, contract
of sale or in any manner or way, whether voluntarily or involuntarily, without
the written consent of LENDER which shall not be unreasonably withheld being
first had and obtained; consent to one transaction under this Paragraph 6(d)
shall not constitute a waiver of the right to require consent to future or
successive transactions; or

            (e) If at any time BORROWER shall admit in writing his inability to
pay his debts as they become due, or shall make any assignment for the benefit
of any creditors, or shall file a petition seeking any reorganization,
arrangement, composition, readjustment or similar release under any present or
future statute, law or regulation, or on the filing or commencement of any
petition, action, case or proceeding, voluntary or involuntary, under any state
or federal law regarding bankruptcy or insolvency.

            7. Offset to Compensation. To the fullest extent permitted by law,
upon any termination for cause of BORROWER'S employment with LENDER, BORROWER
hereby authorizes LENDER to offset any unpaid principal balance or interest due
under this Note against any amounts owed by LENDER to BORROWER, including, but
not limited to, any wages, salary, bonuses, accrued vacation or sick pay, and
any other employment or consulting compensation or stock repurchase payments.
LENDER shall promptly notify BORROWER in writing of any such offset, including
an itemization of the amounts offset and the balance, if any, due and payable
pursuant to this Note.

            8. Collection Costs Borne by BORROWER. BORROWER agrees to pay the
reasonable costs and expenses, including without limitation reasonable
attorneys' fees, incurred by LENDER in any action brought to enforce the terms
of this Note and/or to collect this Note, and any appeal thereof.

            9. Miscellaneous.

            (a) No delay or omission on the part of LENDER in exercising any
right under this Note or under the Deed of Trust or any other security agreement
given to secure this Note shall operate as a waiver of such right or of any
other right under this Note.

            (b) BORROWER expressly waives presentment, protest and demand,
notice to protest, demand and dishonor and nonpayment of this Note and all other
notices of any kind, and expressly agrees that this Note, or any payment
thereunder, may be extended from time to time without in any way affecting the
liability of BORROWER and endorsers hereof.

            10. Late Charge. If payment of principal or interest under this Note
shall not be made within 10 days after the date due, BORROWER agrees to pay, in
addition to the unpaid principal and interest, interest on any such unpaid
amount at a rate of one and one-half percent (1.5%) per month, or at the maximum
rate allowed by law, whichever is less. BORROWER agrees that the above-noted
calculation represents a fair and reasonable estimate, considering all of the
circumstances existing on the date of this Note, of the costs and expenses
incident to handling and collecting such delinquent payment that will be
sustained by LENDER due to the failure of BORROWER to make timely payment. The
parties further agree that proof of actual damages would be costly and
impracticable. Such charge shall be paid without prejudice to the right of
LENDER to collect any other amounts provided to be paid or to declare a default
under this Note or under the Deed of Trust referred to in this Note or from
exercising any of the other rights and remedies of LENDER.

            11. Notices Under Other Obligations. BORROWER shall promptly send to
LENDER copies of any notices received by BORROWER from the holder of any other
deed of trust or mortgage encumbering the Property.


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            12. Governing Law. The Note shall be governed by the laws of the
State of California and shall be construed in accordance therewith.

            13. Successors. This Note shall be binding upon BORROWER and the
personal representatives, heirs, successors and assigns of BORROWER.

            14. Severability. If any part of this Note is determined to be
illegal or unenforceable, all other parts shall remain in full force and effect.

            BORROWER has set his hand to this Note effective as of the date set
forth above.

            Dated: May 15, 1999.

                                           /s/ KEITH ROBINSON
                                           -------------------------------------
                                           KEITH ROBINSON

            I, JANICE D. ROBINSON, the spouse of BORROWER, do hereby consent to
the borrowing by BORROWER of the loan evidenced by this Note on the terms and
conditions set forth herein and to the granting of the Deed of Trust referred to
in Paragraph 5 of this Note to secure the obligations of BORROWER under this
Note.

                                           /s/ JANICE D. ROBINSON
                                           ------------------------------------
                                           JANICE D. ROBINSON


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