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                                                                   Exhibit 10.18


                     THIRD AMENDMENT TO INVESTMENT AGREEMENT
                     ---------------------------------------

     This Third Amendment, dated as of March 28, 2002 (this "Third Amendment"),
to the Investment Agreement, dated as of June 9, 2000, as amended by the First
Amendment, dated as of September 11, 2000, and the Second Amendment, dated as of
January 30, 2001 (collectively, the "Investment Agreement") is made by and
between TiVo Inc., a Delaware corporation (the "Company"), and America Online,
Inc., a Delaware corporation (the "Purchaser"). Capitalized terms used but not
defined herein shall have the meanings assigned to them in the Investment
Agreement.

     WHEREAS, Section 7.8 of the Investment Agreement provides for the amendment
of the Investment Agreement upon the written consent of the Company and the
Purchaser;

     WHEREAS, the Company and the Purchaser desire to amend certain provisions
of the Investment Agreement;

     NOW THEREFORE, the parties hereto agree as follows:

     1.  Amendment to Section 1.4(b). Section 1.4(b) of the Investment Agreement
         -------------------------------------------
is hereby amended by deleting such section in its entirety and substituting
therefore the following:

          "(b) If (i)(x) the bona fide commercial release and deployment ("Set
     Top Box Launch") of the Integrated Product (as defined in the Commercial
     Agreement) has not occurred by December 31, 2001, or such later date as may
     be mutually agreed by the Company and the Purchaser pursuant to Section 3.6
     of the Commercial Agreement or otherwise (the "Planned Launch Date"), and
     (y) the Purchaser has not committed a Material Breach (as defined in the
     Commercial Agreement) of the Commercial Agreement that has not been cured
     or waived at such time, or (ii) the Company breaches its obligations
     pursuant to Section 6.9, Section 6.10 or Section 6.13 of this Agreement
     (collectively, the "Financial Covenants"), then the Purchaser shall have
     the option (the "Put Option"), exercisable for a period of one hundred
     (100) days following the Planned Launch Date or each such breach, as the
     case may be, subject to the further provisions set forth herein, to require
     the Company, exercisable by written notice to such effect to the Company,
     to repurchase that number of Preferred Shares having an initial liquidation
     value equal to the amount of the Escrowed Funds at such time (excluding any
     interest included therein) (the "Put Amount") and, if all the Preferred
     Shares then outstanding have an aggregate initial liquidation value of less
     than the Put Amount, then the Purchaser may also require the Company to
     repurchase a number of shares of Common Stock held by the Purchaser having
     a value (calculated as the product of the number of shares of Common Stock
     and the Common Stock Price paid by the Purchaser) equal to the difference
     between the aggregate initial liquidation value of the Preferred Shares, if
     any, and the Put Amount. The aggregate purchase price for the repurchase of
     Shares pursuant to this Section 1.4(b) shall be deemed paid by the release
     to the Purchaser of all

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     the Escrowed Funds (including all interest included therein); provided that
                                                                   --------
     the amount of the interest earned on funds deposited into the Escrow
     Account to be released to the Purchaser shall be reduced by the amount of
     dividends actually paid in cash to the Purchaser on the Preferred Shares,
     subject to a maximum equal to the amount of all such interest.
     Notwithstanding the foregoing, in the event that the Set Top Box Launch
     occurs after the Planned Launch Date, but prior to the exercise of the Put
     Option, the Put Option under clause (i) above shall immediately expire and
     be of no further force of effect.

          In the event that the Put Option is exercised in accordance with the
     terms of this Section 1.4(b), the closing of such repurchase shall occur as
     soon as practicable following delivery of the Purchaser's notice of
     exercise, subject to the receipt of necessary governmental approvals. The
     Company agrees to use its best efforts to obtain all such governmental
     approvals and take all such other actions as shall be required to
     consummate such repurchase. At such closing, the Purchaser shall deliver to
     the Company certificates representing the Shares to be repurchased and the
     Company shall deliver to the Purchaser and the Escrow Agent under the
     Escrow Agreement any notice of release or other instrument reasonably
     requested by either of them to effectuate the release of the Escrowed Funds
     (including all interest earned thereon, subject to the proviso in the
     second sentence of this Section 1.4(b)) in accordance with the terms of the
     Escrow Agreement and this Section 1.4(b). It is agreed that, in the event
     the Purchaser is entitled to exercise the Put Option pursuant to clause
     (ii) of the first sentence of this Section 1.4(b), such exercise shall be
     in addition to and without limiting any other remedy or right, whether at
     law or equity, that the Purchaser may have as a result of the breach of a
     Financial Covenant.

          2.  Counterparts. This Third Amendment may be executed simultaneously
              ------------
     or in any number of counterparts, each of which shall be deemed to be an
     original, and all of which shall constitute one and the same instrument.

          3.  Effective Date; No Other Amendments. Each of the parties hereto
              -----------------------------------
     agrees that the amendment to the Investment Agreement contained herein
     shall be effective as of the date and year first above written upon
     execution of this Third Amendment by each party hereto. Except as expressly
     amended hereby, the provisions of the Investment Agreement are hereby
     ratified and confirmed by the parties and shall remain in full force and
     effect. This Third Amendment shall not constitute a waiver or alteration of
     any of the Purchaser's or the Company's other rights and obligations under
     the Investment Agreement or any other agreement between the Purchaser and
     the Company. All references in the Investment Agreement to "this Agreement"
     shall be read as references to the Investment Agreement, as amended by the
     First Amendment, the Second Amendment and this Third Amendment.

          4.  Construction and Governing Law. This Third Amendment shall be
              ------------------------------
     construed together with, and as a part of, the Investment Agreement and
     shall be governed in all respects by the laws of the State of New York as
     such laws are applied to agreements to be performed entirely in such state.

                                       2

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          IN WITNESS WHEREOF, each of the undersigned has executed this Third
     Amendment dated as of the date first written above.



                             TIVO INC.

                             By:          /s/ Matthew P. Zinn
                                ----------------------------------------
                                Name:    Matthew P. Zinn
                                Title:   Vice President & General Counsel


                             AMERICA ONLINE, INC.

                             By:         /s/ Lynda Clarizio
                                ----------------------------------------
                                Name:    Lynda Clarizio
                                Title:   Senior Vice President



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