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                                                                    Exhibit 10.9

          Confidential treatment has been requested for portions of this
          exhibit. The copy filed herewith omits the information subject to the
          confidentiality request. Omissions are designated as [*]. A complete
          version of this exhibit has been filed separately with the Securities
          and Exchange Commission.

                         Addendum to TiVo/NBC Agreement
                         ------------------------------

          This addendum ("Addendum"), having an effective date of August 8, 2001
                          --------
("Addendum Effective Date"), is made to the agreement by and between TiVo, Inc.
 ------------------------
("TiVo") and NBC Multimedia, Inc. dated April 16, 1999 (such agreement
  ----
hereinafter referred to as the "Agreement"). National Broadcasting Company, Inc.
                                ---------
("NBC") is the successor in interest to NBC Multimedia, Inc. for purposes of
  ---
this Addendum.

     WHEREAS, NBC is purchasing notes and warrants convertible into TiVo common
stock as part of a private placement offering (the "Transaction"); and

     WHEREAS, in connection with the Transaction, NBC is entering into a letter
agreement (the "Letter Agreement") with TiVo effective as of the Addendum
                ----------------
Effective Date pursuant to which NBC will [*] for TiVo's provision of the
services set forth in this Addendum (as further described below, the
"Services").
 --------
     NOW THEREFORE, the parties hereby agree that the Agreement is hereby
further amended and supplemented as follows:

     1. All capitalized terms used but not otherwise defined herein shall have
the meaning specified in the Agreement.

     2. In consideration of [*] pursuant to the Letter Agreement, TiVo shall
provide the following services (the "Services") for the time period between
                                     --------
August 9, 2001 and August 9, 2003 (the "Extension Period"):
                                        ----------------

     A.   Basic Showcase. NBC will receive one (1) Basic Showcase for one of its
          --------------
          unique networks (each, an "NBC Programming Service") ( [*] per year
                                     -----------------------
          for each unique network). NBC shall have the right to update the text
          of the Basic Showcase twice per week. "Basic Showcase" shall mean the
                 --------------
          series of text screens available to users of the TiVo Service through
          a link on the main screen which are branded by programming entities,
          highlight the current and upcoming programming of those programming
          entities, and enable users of the TiVo Service to record those
          programs.

     B.   Enhanced Showcase. When the Enhanced Showcase is available for
          -----------------
          deployment, TiVo will provide NBC with notice thereof, and NBC shall,
          as soon as economically and technically practicable, as determined in
          NBC's reasonable discretion, upgrade its Basic Showcase to an Enhanced
          Showcase. When NBC upgrades to the Enhanced Showcase, NBC shall
          provide TiVo

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[*] Certain information on this page has been omitted and filed separately with
the Securities and Exchange Commission. Confidential treatment has been
requested with respect to the omitted portions.

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          with additional consideration in cash [*] (the annual cost difference
          between an Enhanced Showcase and a Basic Showcase), prorated for the
          remainder of the Extension Period as of the time of the upgrade. When
          the Enhanced Showcase is deployed, then in addition to such twice per
          week text updating available with the Basic Showcase, NBC shall be
          able to brand the background graphics of the Enhanced Showcase.
          "Enhanced Showcase" shall mean the Basic Showcase enhanced to enable
           -----------------
          NBC to brand the background with graphics.

     C.   Anchor Position. NBC shall receive an Anchor Screen Position in the
          ---------------
          Network Showcase Area of the TiVo Service for one Showcase (either
          Basic or Enhanced as described above). The Anchor Screen Position [*]
          per year. "Anchor Screen Position" shall mean the front (or top level
                     ----------------------
          screen) of the Network Showcase Area of the TiVo Service, without
          scroll. "Network Showcase Area" shall mean an area available to users
                   ---------------------
          of the TiVo Service through a link on the main screen of the TiVo
          Service which area would contain the NBC Basic Showcase or Enhanced
          Showcase, as applicable.

     D.   Ipreviews: During the Extension Period, TiVo shall work with NBC to
          ---------
          embed data tags within NBC promotions to allow remote instructions
          from viewers for the recording of the promoted programming
          ("Ipreviews"), and NBC shall use its best efforts, subject to
            ---------
          commercial and technical feasibility as determined in NBC's reasonable
          business judgement, to run Ipreview-enabled promotions 24 hours a day,
          7 days a week.

     E.   Viewer Data: As of the time it becomes commercially and technically
          -----------
          feasible, and from that point until the end of the Extension Period,
          TiVo shall provide to NBC viewership and usage data from users of the
          TiVo Service that is related to the products and services addressed in
          the Agreement (as such products and services relate to NBC) that is
          equivalent in content and frequency to the basic reporting TiVo
          provides to any of its other cable or broadcasting television network
          partners. NBC shall have the right to request customized reporting,
          provided that such customized reporting shall be provided by TiVo at a
          fee to be mutually agreed to in writing by TiVo and NBC. At no time
          will TiVo be required to violate any law or any of its published
          Privacy Policies in connection with any reporting provided NBC
          hereunder.

     3. Marketing, Promotion, and Advertising: NBC and TiVo may, in their sole
        -------------------------------------
discretion, agree to use commercially reasonable efforts to exploit
opportunities to promote, respectively, the TiVo Service and the NBC networks
and programming thereon. NBC may, in its sole discretion, work with TiVo to
issue a joint press release mutually approved

----------
[*] Certain information on this page has been omitted and filed separately with
the Securities and Exchange Commission. Confidential treatment has been
requested with respect to the omitted portions.

                                       2

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of by both parties announcing the relationship contemplated by this Addendum,
provided however, that except as required by law or applicable regulatory
requirements, neither NBC nor TiVo will issue a press release or other public
announcement using the other party's name or concerning this Addendum, the
contents thereof or the parties' relationship as a result thereof, without the
prior consent of the other party.

     4. Relationship with the Letter Agreement. The parties acknowledge that
        -------------------------------------
terms and consideration of this Addendum are inexplicably intertwined and
expressly linked to the terms and consideration contained in the Letter
Agreement such that the terms of the Addendum cannot be viewed on their own.

     5. Alterations: TiVo will not make any alterations, modifications, or
        -----------
deletions to any program or content (including, without limitation, advertising
and promotional content) exhibited on any NBC Programming Service or provided
hereunder by NBC ("NBC Content"), including, without limitation, credit
                   -----------
obligations and copyright and trademark notices appearing on or as part of the
NBC Content.

     6. Additional Advertising and Promotional Content: NBC may, in its sole
        ----------------------------------------------
discretion, include additional advertisements or sponsorship materials before,
after or within any NBC Programming Service program or content that has been
recorded and made available to TiVo viewers over the TiVo Service (including the
"pause time" created by the TiVo service). If NBC seeks to include any such
additional advertisements or sponsorship materials, then the parties will
negotiate in good faith a revenue-sharing arrangement with respect thereto and
NBC shall be responsible for the delivery of all necessary materials to TiVo in
connection with any such advertisements or sponsorships and all production and
clearance costs required in connection therewith. TiVo will not overlay, include
or otherwise place any advertising or sponsorship within any NBC Content or any
NBC Programming Service without the express written permission of NBC in each
instance.

     7.   Indemnification.
          ---------------

          A.   NBC will secure all necessary rights and permissions to include
               any NBC Programming Service in the TiVo Service. NBC shall
               indemnify, defend and hold harmless TiVo (and its shareholders,
               successors, assigns, officers, directors and employees) from any
               claims, losses, damages, judgements, liabilities, costs and
               expenses (including reasonable outside attorneys' fees and costs)
               ("Claim") arising from any claims alleging that any NBC
                 -----
               Programming Service infringes upon any rights or interests of any
               third party.

          B.   TiVo will secure all necessary rights and permissions for the
               operation of the TiVo service. TiVo shall indemnify, defend and
               hold harmless NBC (and its shareholders, successors, assigns,
               officers, directors and employees) from any Claim arising from
               any claims alleging that the TiVo Service infringes any rights or
               interests of any third party.

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          C.   A party seeking indemnification hereunder (the "Indemnifed
                                                               ----------
               Party") shall give prompt written notice to the other party (the
               -----
               "Indemnifying Party") of any Claim which may give rise to
                ------------------
               indemnification obligations hereunder. The Indemnified Party
               shall, at its sole expense, control the defense of any Claim with
               counsel approved of by the Indemnified Party, which approval
               shall not be unreasonably withheld, delayed or conditioned. The
               Indemnified Party shall cooperate reasonably in the defense of
               any Claim.

     8. Force Majeure. Notwithstanding any other provision in the Agreement to
        -------------
the contrary, neither party hereto shall have any liability to the other party
or any other person with respect to any failure of such party to perform its
obligations hereunder due to the occurrence of any event beyond such party's
reasonable control, including (but not limited to) any labor dispute, fire,
flood, riot, act of God, legal enactment, governmental order or regulation, or
failures or delays of utilities, suppliers or carriers.

     9. Term: Notwithstanding anything set forth in Section 17(a) of the
        ----
Agreement, the Term is extended to the last day of the Extension Period,
provided however that the [*] period for a "Right of First Negotiation" set
forth in Section 18 of the Agreement will end on [*].

     10. Effect of Addendum. The terms of this Addendum supercede and replace
         ------------------
any conflicting terms contained in the Agreement, provided, however, that except
as expressly set forth herein, nothing contained in this Addendum shall amend,
change, modify, or alter any other provision in the Agreement.

     IN WITNESS WHEREOF, the parties hereto have caused this Addendum to be
executed by their respective duly authorized representatives to be effective as
of the date first written above.

National Broadcasting Company, Inc.         TiVo, Inc.


By:                                         By:
    ---------------------------------           --------------------------------
Name:                                       Name:
      -------------------------------             ------------------------------
Its:                                        Its:
    ---------------------------------           --------------------------------

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[*] Certain information on this page has been omitted and filed separately with
the Securities and Exchange Commission. Confidential treatment has been
requested with respect to the omitted portions.

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