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                                                                    EXHIBIT 10.1

EXECUTION                                                           CONFIDENTIAL

              THIRD ADDENDUM TO OVERTURE SEARCH SERVICES AGREEMENT

This Third Addendum (the "Third Addendum") is effective as of April 25, 2003
(the "Third Addendum Effective Date") and entered into by and between Overture
Services, Inc. ("Overture"), a Delaware corporation with offices at 74 North
Pasadena Avenue, 3d Floor, Pasadena, CA 91103, and Yahoo! Inc. ("Yahoo"), a
Delaware corporation with offices at 701 First Avenue, Sunnyvale, CA 94089, in
connection with the Overture Search Services Agreement effective as of May 1,
2002 and entered into by and between Overture and Yahoo, as amended by the First
Addendum to Overture Search Services Agreement effective as of October 1, 2002
and the Second Addendum to Overture Search Services Agreement effective as of
January 10, 2003 (collectively referred to as the "Agreement").

                                    RECITALS

         WHEREAS, the Agreement provides for, among other things, the delivery
by Overture and the display by Yahoo of sponsored search results in response to
search queries conducted through Yahoo's principal, U.S. targeted directory to
the World Wide Web.

         WHEREAS, the parties anticipate expanding their strategic relationship
such that Overture will provide Yahoo with [*] sponsored search results (the
"[*] Results") in response to [*] search queries (the "[*] Queries") conducted
on http://www.yahoo.com or on any Yahoo Foreign Property as determined by Yahoo
and Overture, and the parties will share revenue generated from these [*]
Results in accordance with this Third Addendum, as further described herein.

         NOW, THEREFORE, in consideration of the mutual promises and conditions
contained herein, and for good and valuable consideration, the parties agree as
follows:

                                    AGREEMENT

1.   Capitalized terms not defined herein have the meanings set forth in the
     Agreement.

2.   Section 4.2(a) in the Agreement is deleted and replaced with the following:

     (a) [*] Overture Results.

         (i) Provision of [*] Results; Implementation. Commencing upon delivery
         of five days prior written notice to Overture of Yahoo's intention to
         implement the [*] Results on Yahoo Search (the "[*] Launch Date"), upon
         receipt by Overture of a Yahoo Search Query that (a) Overture
         determines to be an [*] Query and (b) contains a [*] provided by Yahoo
         that indicates the [*] Results, Overture will deliver [*] Results to
         Yahoo for implementation on Yahoo Search in accordance with subpart
         (ii) below. The manner of implementation of [*] Results on Yahoo Search
         will be determined by [*], and will not be subject to [*] or
         specifications regarding [*]). Without limiting the foregoing, Yahoo
         will, on the [*] Launch Date only, display Yahoo Search Results Pages
         containing [*] Results in a manner substantially similar to the U.S.
         Implementation as of the [*] Launch Date. Upon the mutual agreement of
         the parties, Yahoo may implement the [*] Results in other areas of the
         Yahoo Network. Overture will deliver [*] Results solely for [*] Queries
         unless otherwise instructed by Yahoo in writing. Overture will send
         Yahoo an updated list of proposed modifications to the [*] keyword list
         on a regular basis during the Term as mutually determined by the
         parties (but no less frequently than on a monthly basis), and Yahoo
         will have the opportunity to approve such modifications prior to
         implementation by Overture. Yahoo will have final editorial review over
         any modifications to the [*] keyword list that is used to deliver [*]
         Results. Such editorial review shall be exercised consistently with
         Yahoo's company-wide [*] concerning [*] content.

         (ii) [*]. Yahoo will include a [*] on each Yahoo Search Query which
         indicates whether the [*] Results. If the [*] indicates that a [*]
         Results, then Overture will suppress [*] Results, at a minimum, to the
         same degree as the [*] that appear on the Overture Site as of the Third
         Addendum Effective Date and will send to

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

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         Yahoo such [*] Overture Results. If the [*] indicates that a [*]
         Results, Overture will determine whether to return [*] Results for such
         Yahoo Search Query in accordance with subpart (i) above.

         (iii) Separate Feed; Reporting; Guaranteed Impressions. As of the Third
         Addendum Effective Date, Overture will account for the [*] Results as a
         separate line item in any reports required hereunder. Any reports for
         [*] Results will include CTR in the aggregate by search result
         position. Yahoo will provide Overture with the same information at the
         time-of-search for each [*] Query as it does for the U.S.
         Implementation, and Overture will be entitled to use and disclose that
         information subject to the use and disclosure restrictions set forth in
         this Agreement. Overture will include a [*] identifying each [*] Result
         as provided by either an [*] Advertiser or a [*] Advertiser. Finally,
         Yahoo will have no obligation to deliver Guaranteed Impressions
         pursuant to Section 9 of this Agreement with respect to the [*]
         Results. Impressions delivered pursuant to the Third Addendum shall not
         count towards the number of Guaranteed Impressions delivered by Yahoo
         under Section 9 of this Agreement.

         (iv) Cancellation; Suspension of [*] Service. Yahoo has the right to
         cancel the delivery or suspend the display of [*] Results at any time
         upon written notice provided to Overture (which notice can be via email
         to legal@overture.com) within one business day of such cancellation or
         suspension. In the event that Yahoo either has cancelled delivery or
         suspended its display of [*] Results, then Overture will suppress [*]
         Results, at a minimum, to the same degree as the [*] that appear on the
         Overture Site as of the Third Addendum Effective Date. Upon receipt by
         Overture of an [*] Query for which Overture has [*] Overture Results,
         Overture will send to Yahoo such [*] Overture Results. For all other
         [*] Queries, Overture shall not return any [*] Results, and if Overture
         does send an [*] Result, then Yahoo shall be entitled to [*] such [*]
         Result from being displayed pursuant to Section 4.5(a) of this
         Agreement.

         (v) Other [*] Service Providers. The parties acknowledge and agree
         that, subject to Section 7.1(b), which Section shall apply to [*]
         Queries, [*].

3.   The following subsection is added to the end of Section 4.5 ("Removal by
     Yahoo; Potential Liability; Excluded Terms; Contextual Relevance") of the
     Agreement:

     (c) [*] Results. As it consistently administers its company-wide [*]
         concerning [*] content, Yahoo will have the right to prevent the
         display of [*] Results in response to [*] Queries at any time during
         the Term.

4.   Payment. Overture will make payments to Yahoo for Gross Revenue earned
     pursuant to this Third Addendum in accordance with the following:

     4.1 Revenue Share Payments. Overture will make Quarterly revenue share
         payments to Yahoo based on Gross Revenue earned from [*] Results (the
         "[*] Gross Revenue") in the applicable Quarter according to the
         schedule set forth below. For purposes of calculating [*] Gross
         Revenue, in determining the amount for subpart (i) in the definition of
         Gross Revenue, the parties shall use Overture's actual amounts for bad
         debt and credit card processing fees, which amounts will not exceed
         [*]%. In calculating the [*] Gross Revenue, the remainder of the
         definition of Gross Revenue remains unchanged. For clarity, for all
         Gross Revenue other than [*] Gross Revenue, the definition of Gross
         Revenue remains unchanged. Payments are due and payable to Yahoo within
         [*] days after the end of the applicable Quarter.

         [*]

         Overture will retain all revenue that it derives from the [*] Results,
         except as specifically set forth in this Third Addendum.

     4.2 Payment Mechanics. Overture will make payments to Yahoo in U.S. dollars
         via wire transfer into Yahoo's main account according to the
         instructions set forth below:

         [*]

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

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     4.3 Late Payments. Any undisputed payment that is paid more than [*] days
         late will bear interest at the rate of [*]% per month.

     4.4 Audit Rights and Data Rights. Except as expressly set forth herein or
         as otherwise agreed by the parties in writing, the audit rights and
         data rights and obligations for the [*] Results will mirror the rights
         and obligations set forth in Sections 8.4 (including Exhibit F) and 8.5
         of the Agreement.

     4.5 No Payment Adjustments. The parties acknowledge and agree that the
         delivery of [*] Results will be tracked separately from the delivery of
         all other Overture Results in Yahoo Search, and that the [*] Results
         will not be included in the calculation of Impressions, Coverage, PPC,
         CTR or of adjustments to the Estimated Yahoo Payment or the Guaranteed
         Fixed Payment under the Agreement.

5.   Term and Termination.

     5.1 Term. This Third Addendum will become effective as of the Third
         Addendum Effective Date and, unless terminated as set forth herein,
         will remain effective for the same period as the Agreement remains
         effective.

     5.2 Termination in connection with Agreement. This Third Addendum will
         terminate to the extent that the Agreement is terminated in accordance
         with its terms, effective as of the effective date of termination of
         the Agreement.

     5.3 Termination with Cause. If either party breaches this Third Addendum in
         any material respect, and that party does not cure its breach within
         [*] after written notice by the non-breaching party of its breach, then
         the non-breaching party will be entitled to terminate this Third
         Addendum immediately upon written notice to the breaching party after
         failure to cure within those [*]. The parties acknowledge and agree
         that a breach under this Third Addendum will not affect the Agreement,
         regardless of whether the breach gives rise to termination of this
         Third Addendum.

     5.4 Termination by Overture. Overture may terminate this Third Addendum for
         [*] upon providing Yahoo with [*] prior written notice.

     5.5 Effect of Termination. Sections 1, 4 (with respect to payments accrued
         during the Term), and 6 through 8 of this Third Addendum will survive
         termination or expiration of this Third Addendum.

6.   Notice of [*] Content. Yahoo will use commercially reasonable efforts to
     provide prompt written notice (as set forth in Section 16.1 of the
     Agreement) to Overture whenever a third party has notified Yahoo that any
     content appearing on the Yahoo Search Results Pages that include [*]
     Results or the content of [*] Advertiser web sites linked to from [*]
     Results contains content that violates any applicable law, rule or
     regulation or infringes the rights of any third party, including but not
     limited to intellectual property rights, privacy and publicity rights,
     claims of defamation, false or deceptive advertising claims, consumer fraud
     or would otherwise violate Yahoo's company-wide [*] concerning [*] content.

7.   Overture Warranties. As of this Third Addendum Effective Date, Overture
     represents and warrants that it has implemented a screening policy whereby
     it screens the Advertiser web page that is directly linked to from the [*]
     Result as part of the initial registration process in an effort to exclude
     from [*] Results web sites that contain the following [*].

8.   Overture Screening Policy Covenant. Overture's screening policies are
     subject to change during the Term; however, (1) Overture will provide Yahoo
     with prompt written notice of any change to its [*] content screening
     policy, and (2) during the Term, Overture will use commercially reasonable
     efforts to exclude [*] Results (at the point in time such [*] Results go
     through the initial registration process described in Section 7) that
     directly link to a web page that contains the [*] content listed in Section
     7. To the extent that Yahoo does not approve of a

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

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     change to Overture's [*] screening policy, then Yahoo may exercise its
     right of cancellation as set forth in Section 4.2(a)(iv) of this Agreement.
     If Yahoo has not exercised this cancellation right after receiving notice
     from Overture as described in this Section, then Overture shall be deemed
     to have complied with its continuing obligations to use commercially
     reasonable efforts to exclude [*] Results that would otherwise violate this
     Section.

9.   Press Release and Public Statements. Each party is expressly prohibited
     from making any press release or public statement related to either party's
     performance under this Third Addendum without the other party's prior
     written approval.

10.  Replacement of "Fraudulent Clicks" with "Invalid Clicks". All instances of
     "Fraudulent Clicks" in this Agreement is hereby replaced with the term
     "Invalid Clicks".

11.  Exclusion of Certain Provisions of the Agreement. For purposes of clarity,
     Sections 2.5, 3.2, 4.3(a) and (b), 5.1, 5.2, 7.1(a), 8.1 through 8.3, 8.6
     through 8.9 and 9 of the Agreement will not apply to this Third Addendum
     solely to the extent that such provisions apply to [*] Queries and the
     display of [*] Results within the Yahoo Network.

                            [signature page follows]

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

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EXECUTION                                                           CONFIDENTIAL

IN WITNESS WHEREOF, the parties have caused this Third Addendum to be executed
by their duly authorized representatives as of the Third Addendum Effective
Date.

YAHOO! INC.                                    OVERTURE SERVICES, INC.

By:    /s/ Jeff Weiner                         By:    /s/ Bill Deamas
       ------------------------------                 --------------------------
Name:  Jeff Weiner                             Name:  Bill Demas
Title: Senior Vice President, Search           Title: Senior Vice President &
       and Marketplace                                General Manager,
                                                      Affiliate Business Group

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