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                                                                   EXHIBIT 99.10

                                                                   INITIAL GRANT

                               ACT NETWORKS, INC.
                    NOTICE OF GRANT OF NON-EMPLOYEE DIRECTOR
                             AUTOMATIC 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: ______________________________________________________

               Grant Date:_____________________________________________________

               Exercise Price:  $ ___________________ per share

               Number of Option Shares: 21,000 shares

               Expiration Date:________________________________________________

               Type of Option:    Non-Statutory Stock Option

               Date Exercisable:  Immediately Exercisable

               Vesting Schedule: The Option Shares shall initially be unvested
               and subject to repurchase by the Corporation at the Exercise
               Price paid per share. Optionee shall acquire a vested interest
               in, and the Corporation's repurchase right shall accordingly
               lapse with respect to, the Option Shares in thirty-six (36)
               successive equal monthly installments upon Optionee's completion
               of each month of service as a member of the Corporation's Board
               of Directors (the "Board") over the thirty six (36)-month period
               measured from the Grant Date. In no event shall any additional
               Option Shares vest after Optionee's cessation of Board service.

               Optionee understands and agrees that the Option is granted
subject to and in accordance with the terms of the automatic option grant
program under the ACT Networks, Inc. 1997 Stock Incentive Plan (the "Plan").
Optionee further agrees to be bound by the terms of the Plan and the terms of
the Option as set forth in the Automatic Stock Option Agreement attached hereto
as Exhibit A. Optionee hereby 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.



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               REPURCHASE RIGHT. OPTIONEE HEREBY AGREES THAT ALL UNVESTED OPTION
SHARES ACQUIRED UPON THE EXERCISE OF THE OPTION SHALL BE SUBJECT TO A REPURCHASE
RIGHT EXERCISABLE BY THE CORPORATION AND ITS ASSIGNS. THE TERMS OF SUCH RIGHT
SHALL BE SPECIFIED IN A STOCK PURCHASE AGREEMENT, IN FORM AND SUBSTANCE
SATISFACTORY TO THE CORPORATION, EXECUTED BY OPTIONEE AT THE TIME OF THE OPTION
EXERCISE.

               No Impairment of Rights. Nothing in this Notice or the attached
Automatic Stock Option Agreement or in the Plan shall interfere with or
otherwise restrict in any way the rights of the Corporation and the
Corporation's stockholders to remove Optionee from the Board at any time in
accordance with the provisions of applicable law.

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

_______________________ , 199__
        Date


                                                   ACT NETWORKS, INC.


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

                                                   Title:
                                                         -----------------------



                                                   -----------------------------
                                                   OPTIONEE

                                                   Address:_____________________

                                                   _____________________________

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

                                       2.

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                                    EXHIBIT A

                        AUTOMATIC STOCK OPTION AGREEMENT




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                                    EXHIBIT B

                           PLAN SUMMARY AND PROSPECTUS




