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                                  EXHIBIT 99.13

               NOTICE OF GRANT OF STOCK OPTION USED IN CONNECTION
                        WITH THE OPTION GRANT TO MR. SADR



                               ACT NETWORKS, INC.
                         NOTICE OF GRANT OF STOCK OPTION


               Notice is hereby given of the following option grant (the
"Option") to purchase shares of the Common Stock of ACT Networks, Inc. (the
"Corporation"):

               Optionee:                  Ramin Sadr
                        -------------------------------------------------------
               Grant Date:                February 10, 2000
                          -----------------------------------------------------
               Vesting Commencement Date: February 10, 2000
                                         --------------------------------------
               Exercise Price:            $8.625   per share
                                          ------

               Number of Option Shares:   200,000  shares
                                          -------
               Expiration Date:         February 9, 2010
                               ------------------------------------------------
               Type of Option:   Non-Statutory Stock Option
                              -------------------------------------------------
               Installment Exercise Schedule: The Option shall become
               exercisable for twenty-four (24%) of the Option Shares upon the
               Optionee's completion of twelve (12) full months of Service
               measured from the Vesting Commencement Date. The Option shall
               become exercisable for the balance of the Option Shares in a
               series of thirty-eight (38) successive equal monthly installments
               upon Optionee's completion of each additional full month of
               Service over the thirty-eight (38)-month period measured from the
               first anniversary of the Vesting Commencement Date. In no event
               shall any additional Option Shares vest after Optionee's
               cessation of Service.

               Although the Option is not granted under ACT Networks, Inc. 1997
Stock Incentive Plan (the "Plan"), the Options shall be governed by terms and
conditions substantially similar to that Plan. Optionee further agrees to be
bound by the terms of the Option as set forth in the Stock Option Agreement
attached hereto as Exhibit A.

               Optionee hereby further acknowledges receipt of a copy of the
official prospectus for the Plan in the form attached hereto as Exhibit B. A
copy of the Plan is available upon request made to the Corporate Secretary at
the Corporation's principal offices.

               No Employment or Service Contract. Nothing in this Notice or in
the attached Stock Option Agreement shall confer upon Optionee any right to
continue in Service for any period of specific duration or interfere with or
otherwise restrict in any way the rights of the Corporation (or any Parent or
Subsidiary employing or retaining Optionee) or of Optionee, which rights are
hereby expressly reserved by each, to terminate Optionee's Service at any time
for any reason, with or without cause.

               Definitions. All capitalized terms in this Notice shall have the
meaning assigned to them in this Notice or in the attached Stock Option
Agreement.

February 10, 2000

                               ACT NETWORKS, INC.


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                                       By:
                                          --------------------------------------

                                       Title: President and CEO


                                       -----------------------------------------
                                       RAMIN SADR

                                       Address:
                                               ---------------------------------


                                       -----------------------------------------

ATTACHMENTS
EXHIBIT A - STOCK OPTION AGREEMENT
EXHIBIT B - PLAN SUMMARY AND PROSPECTUS

