EXHIBIT 4.3
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                         AMENDMENT TO RIGHTS AGREEMENT
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     This Amendment, dated as of November 7, 1996, amends the Rights Agreement
dated as of December 1, 1995 (the "Rights Agreement") between FTP Software,
Inc., a Massachusetts corporation (the "Company"), and State Street Bank and
Trust Company, a national banking association (the "Rights Agent").

     WHEREAS, the Board of Directors of the Company has approved an amendment to
the Rights Agreement pursuant to Section 27 thereof;

     NOW THEREFORE, in consideration of these premises, the mutual agreements
herein set forth, and other good and valuable consideration, the sufficiency of
which is hereby acknowledged by each party, the parties hereto hereby agree as
follows:

     1.  Amendment.  The definition of "Acquiring Person" set forth in Section
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1(a) of the Rights Agreement is hereby amended to read as follows:

          "(a)  "Acquiring Person" shall mean any Person who or which, together
     with all Affiliates of such Person, shall be the Beneficial Owner of 15% or
     more of the shares of Common Stock then outstanding, but shall not include
     (i) the Company, (ii) any Subsidiary of the Company, (iii) any employee
     benefit plan of the Company or of any Subsidiary of the Company, (iv) any
     Person organized, appointed, or established by the Company or a Subsidiary
     of the Company pursuant to the terms of any plan described in clause (iii)
     above or (v) any Person who has reported or is required to report its or
     their beneficial ownership (but less than 20%) on Schedule 13G under the
     Exchange Act (or any comparable or successor report) or on Schedule 13D
     under the Exchange Act (or any comparable or successor report) which
     Schedule 13D does not state any intention to or reserve the right to
     control or influence the management or policies of the Company or engage in
     any of the actions specified in Item 4 of such Schedule (other than the
     disposition of the Common Stock) and, within 10 Business Days of being
     requested by the Company to advise it regarding the same, certifies to the
     Company that such Person acquired shares of Common Stock in excess of 14.9%
     inadvertently or without knowledge of the terms of the Rights and who,
     together with all of such Person's Affiliates, thereafter does not acquire
     additional shares of Common Stock while the Beneficial Owner of 15% or more
     of the shares of Common Stock then outstanding, provided, however, that if
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     the Person requested to so certify fails to do so within 10 Business Days,
     then such Person shall become an Acquiring Person on the day immediately
     following the last day of such 10 Business Day Period; and provided,
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     further, that "Acquiring Person" shall not include Kopp Investment
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     Advisors, Inc. (but no purchaser or assignee of such Person or direct or
     indirect purchaser or transferee of

 
     any shares of Common Stock of the Company from such Person) ("Kopp") so
     long as (x) the shares of Common Stock of the Company beneficially owned by
     Kopp do not exceed 6,722,400 shares (such number to be adjusted in the
     event of any stock dividend, stock split or combination of shares,
     recapitalization, repurchase of shares by the Company or any other change
     in the Company's capital stock which in the determination of the Board in
     its sole discretion requires an adjustment to such number to maintain it at
     less than 20% of the Company's outstanding shares) and (y) Kopp has not
     filed a Schedule 13D or Schedule 13G that expresses any intention or
     reservation of the right to control or influence the management or policies
     of the Company or to engage in any of the actions specified in Item 4 of
     such Schedule 13D (other than the disposition of Common Stock)."

     2.  Effect of Amendment.  Except as expressly amended hereby, the Rights
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Agreement shall remain in full force and effect.

     3.  Governing Law.  This Amendment shall be deemed to be a contract made
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under the laws of The Commonwealth of Massachusetts and for all purposes shall
be governed by and construed in accordance with the laws of said state
applicable to contracts made and to be performed entirely within said state.

     4.  Counterparts.  This Amendment may be executed in any number of
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counterparts and each of such counterparts shall for all purposes be deemed to
be an original, and all such counterparts shall together constitute but one and
the same instrument.

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and delivered as of the day first above written.

ATTEST:                       FTP SOFTWARE, INC.



                              By 
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                                Name:
                                Title:

ATTEST:                       STATE STREET BANK AND TRUST
                              COMPANY



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


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