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Filed Pursuant to Rule 424(b)(3)
Registration No. 333-105766

PROSPECTUS SUPPLEMENT NO. 10
(To Prospectus dated August 26, 2003)

        This prospectus supplement supplements the prospectus dated August 26, 2003, as supplemented by prospectus supplement No. 1 dated September 9, 2003, prospectus supplement No. 2 dated September 26, 2003, prospectus supplement No. 3 dated October 27, 2003, prospectus supplement No. 4 dated November 13, 2003, prospectus supplement No. 5 dated February 9, 2004, prospectus supplement No. 6 dated March 4, 2004, prospectus supplement No. 7 dated April 9, 2004, prospectus supplement No. 8 dated April 20, 2004 and prospectus supplement No. 9 dated May 19, 2004 of Yahoo! Inc. relating to the resale from time to time by selling securityholders of our Zero Coupon Senior Convertible Notes due 2008 held by certain securityholders and the shares of our common stock issuable upon conversion of the Notes. This prospectus supplement should be read in conjunction with the prospectus, as supplemented, and this prospectus supplement is qualified by reference to the prospectus, as supplemented, except to the extent that the information provided by this prospectus supplement supersedes the information contained in the prospectus, as supplemented.

        The SECURITIES offered in the prospectus involve a high degree of risk. You should carefully consider the "Risk Factors" referenced on page 5 of the prospectus in determining whether to purchase the Yahoo! Inc. Zero Coupon Senior Convertible Notes due 2008 or the Common Stock.


        Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the adequacy or accuracy of this prospectus supplement. Any representation to the contrary is a criminal offense.


        The section of the prospectus entitled "Selling Securityholders" on pages 46 – 51 of the prospectus is amended and restated in its entirety to read as follows:


SELLING SECURITYHOLDERS

        The Notes were originally issued to and resold by Credit Suisse First Boston LLC in transactions exempt from the registration requirements of the Securities Act to persons reasonably believed by them to be "qualified institutional buyers," as defined by Rule 144A under the Securities Act and Regulation S. The selling securityholders may from time to time offer and sell pursuant to this prospectus any or all of the Notes and the common stock into which the Notes are convertible. When we refer to the "selling securityholders" in this prospectus, we mean those persons listed in the table below, as well as their transferees, pledgees, donees or successors.

        The table below sets forth the name of each selling securityholder, the principal amount of Notes at maturity that each selling securityholder may offer pursuant to this prospectus and the number of shares of common stock into which the Notes are convertible. Unless set forth below, none of the selling securityholders has had within the past three years any material relationship with us or any of our predecessors or affiliates.

        We have prepared the following tables based on information given to us by the selling securityholders on or before July 27, 2004. The selling securityholders may offer, pursuant to this prospectus, all or some portion of the Notes or common stock listed below, as a result, no estimate can be given as to the amount of Notes or common stock that will be held by the selling securityholders upon consummation of any sales.

        Information about the selling securityholders may change over time. Any changed information given to us by the selling securityholders will be set forth in prospectus supplements if and when necessary.



SELLING SECURITYHOLDERS TABLE

Selling Securityholder
  Principal Amount at
Maturity of Notes
Beneficially Owned
and Offered

  Percentage of
Outstanding Notes

  Common Stock
Issuable Upon
Conversion of the
Notes that May
Be Sold(1)

  Percentage of
Shares of
Common Stock
Outstanding(2)

 
AIG DKR SoundShore Opportunity Holding Fund Ltd.   $ 3,000,000   *   146,341   *  
AIG DKR SoundShore Strategic Holding Fund Ltd.   $ 3,000,000   *   146,341   *  
Alexandra Global Master Fund LTD   $ 5,000,000   *   243,902   *  
American AAdvantage Funds   $ 190,000   *   9,268   *  
Arbitex Master Fund, L.P.   $ 27,000,000   3.60%   1,317,070   *  
Arpeggio Fund   $ 8,500,000   1.13%   414,633   *  
Aventis Pension Master Trust   $ 260,000   *   12,682   *  
Bank Austria Cayman Islands, LTD   $ 7,000,000   *   341,462   *  
Bank of America Pension Plan   $ 1,000,000   *   48,780   *  
Barclays Global Investors Ltd.   $ 1,000,000   *   48,780   *  
Bear, Stearns & Co. Inc.   $ 5,000,000   *   243,902   *  
BNP Paribas Equity Strategies, SNC   $ 57,000   *   2,780   *  
Boilermaker – Blacksmith Pension Trust   $ 1,350,000   *   65,853   *  
CALAMOS® Convertible Fund – CALAMOS® Investment Trust   $ 12,200,000   1.63%   595,120   *  
CALAMOS® Convertible Growth and Income Fund – CALAMOS® Investment Trust   $ 12,800,000   1.71%   624,389   *  
CALAMOS® Convertible Portfolio – CALAMOS® Advisors Trust   $ 165,000   *   8,048   *  
CALAMOS® Global Convertible Fund – CALAMOS® Investment Trust   $ 230,000   *   11,219   *  
CEMEX Pension Plan   $ 125,000   *   6,097   *  
CGNU Life Fund   $ 1,000,000   *   48,780   *  
City of Albany Pension Plan   $ 140,000   *   6,829   *  
City of Knoxville Pension System   $ 300,000   *   14,634   *  
Commercial Union Life Fund   $ 1,300,000   *   63,414   *  
Consulting Group Capital Market Funds   $ 1,000,000   *   48,780   *  
CooperNeff Convertible Strategies (Cayman) Master Fund, LP   $ 66,000   *   3,219   *  
Credit Suisse First Boston LLC   $ 120,000   *   5,853   *  
CSU Limited   $ 1,700,000   *   82,926   *  
DBAG London   $ 5,000,000   *   243,902   *  
Deep Rock & Co.   $ 1,000,000   *   48,780   *  
Delta Airlines Master Trust   $ 1,400,000   *   68,292   *  
Delta Pilots Disability and Survivorship Trust   $ 400,000   *   19,512   *  
Deutsche Bank Securities Inc.   $ 500,000   *   24,390   *  
Dodeca Fund, L.P.   $ 1,025,000   *   49,999   *  
Dorinco Reinsurance Company   $ 750,000   *   36,585   *  
Drake Offshore Master Fund Ltd.   $ 10,000,000   1.33%   487,804   *  
Duckbill & Co.   $ 500,000   *   24,390   *  
Gasner Investors Holdings Ltd.   $ 1,000,000   *   48,780   *  
General Motors Welfare Benefit Trust   $ 3,000,000   *   146,341   *  
GLG Market Neutral Fund   $ 25,000,000   3.33%   1,219,510   *  
GMAM Group Pension Trust   $ 500,000   *   24,390   *  
Goldman Sachs & Co. Profit Sharing Master Trust   $ 1,007,000   *   49,121   *  
Guggenheim Portfolio Co. XV, LLC   $ 1,500,000   *   73,170   *  
Highbridge International LLC   $ 25,000,000   3.33%   1,219,510   *  
IMF Convertible Fund   $ 1,000,000   *   48,780   *  
Inflective Convertible Opportunity Fund I, L.P.   $ 25,000   *   1,219   *  
JP Morgan Securities Inc.   $ 9,500,000   1.27%   463,413   *  
                     

S-2


KBC Convertible Arbitrage Fund   $ 30,800,000   4.11%   1,502,436   *  
KBC Convertible Mac28 Fund, Ltd.   $ 2,800,000   *   136,585   *  
KBC Financial Products [Cayman Islands] Ltd.   $ 4,520,000   *   220,487   *  
KBC Financial Products USA Inc.   $ 3,760,000   *   183,414   *  
Kettering Medical Center Funded Depreciation Account   $ 80,000   *   3,902   *  
Knoxville Utilities Board Retirement System   $ 130,000   *   6,341   *  
Lehman Brothers Inc.   $ 9,500,000   1.27%   463,413   *  
Louisiana Workers' Compensation Corporation   $ 350,000   *   17,073   *  
Lyxor/Convertible Arbitrage Fund Limited   $ 6,000   *   292   *  
Lyxor Master Fund   $ 2,000,000   *   97,560   *  
Macomb County Employees' Retirement System   $ 290,000   *   14,146   *  
Man Convertible Bond Master Fund, Ltd.   $ 15,032,000   2.00%   733,266   *  
Melody IAM, Ltd   $ 1,400,000   *   68,292   *  
Nomura Securities International   $ 2,000,000   *   97,560   *  
Norwich Union Life & Pensions   $ 2,000,000   *   97,560   *  
OZ Convertible Master Fund, Ltd.   $ 4,389,000   *   214,097   *  
OZ MAC 13 Ltd.   $ 1,157,000   *   56,438   *  
OZ Master Fund, Ltd.   $ 50,947,000   6.79%   2,485,215   *  
Pacific Life Insurance Company   $ 500,000   *   24,390   *  
Peoples Benefit Life Insurance Company Teamsters   $ 3,000,000   *   146,341   *  
Port Authority of Allegheny County Retirement and Disability Allowance Plan for the Employees Represented by Local 85 of the Amalgamated Transit Union   $ 680,000   *   33,170   *  
Prisma Foundation   $ 40,000   *   1,951   *  
Ramius Capital Group   $ 1,000,000   *   48,780   *  
Ramius Master Fund, LTD   $ 11,575,000   1.54%   564,633   *  
Ramius Partners II, LP   $ 300,000   *   14,634   *  
Ramius, LP   $ 200,000   *   9,756   *  
RCG Baldwin, LP   $ 800,000   *   39,024   *  
RCG Halifax Master Fund, LTD   $ 1,500,000   *   73,170   *  
RCG Latitude Master Fund, LTD   $ 11,575,000   1.54%   564,633   *  
RCG Multi Strategy Master Fund, LTD   $ 650,000   *   31,707   *  
Retail Clerks Pension Trust   $ 3,000,000   *   146,341   *  
Retail Clerks Pension Trust #2   $ 1,000,000   *   48,780   *  
Rhapsody Fund, LP   $ 13,960,000   1.86%   680,974   *  
Salomon Brothers Asset Management, Inc.   $ 10,000,000   1.33%   487,804   * (3)
SCI Endowment Care Common Trust Fund – First Union   $ 35,000   *   1,707   *  
SCI Endowment Care Common Trust Fund – National Fiduciary Services   $ 190,000   *   9,268   *  
SCI Endowment Care Common Trust Fund – Suntrust   $ 80,000   *   3,902   *  
Singlehedge US Convertible Arbitrage Fund   $ 9,000   *   439   *  
South Dakota Retirement System   $ 5,000,000   *   243,902   *  
SPT   $ 1,700,000   *   82,926   *  
St. Albans Partners Ltd.   $ 4,000,000   *   195,121   *  
St. Thomas Trading, Ltd.   $ 24,968,000   3.33%   1,217,949   *  
Sturgeon Limited   $ 6,000   *   292   *  
TCW Group Inc.   $ 7,410,000   *   361,462   *  
                     

S-3


The California Wellness Foundation   $ 400,000   *   19,512   *  
The Dow Chemical Company Employees' Retirement Plan   $ 2,700,000   *   131,707   *  
The Fondren Foundation   $ 145,000   *   7,073   *  
UBS A6 London Branch   $ 64,000,000   8.53%   3,121,945   *  
UBS Securities LLC   $ 100,000   *   4,878   *  
Union Carbide Retirement Account   $ 1,200,000   *   58,536   *  
United Food and Commercial Workers Local 1262 and Employers Pension Fund   $ 600,000   *   29,268   *  
Univar USA Inc. Retirement Plan   $ 300,000   *   14,634   *  
Wachovia Bank National Association   $ 10,000,000   1.33%   487,804   *  
Wachovia Capital Markets LLC   $ 250,000   *   12,195   *  
White River Securities L.L.C.   $ 5,000,000   *   243,902   *  
WPG Convertible Arbitrage Overseas Master Fund   $ 750,000   *   36,585   *  
WPG MSA Convertible Arbitrage Fund   $ 250,000   *   12,195   *  
Xavex Convertible Arbitrage #5   $ 900,000   *   43,902   *  
Yield Strategies Fund I, L.P.   $ 2,000,000   *   97,560   *  
Yield Strategies Fund II, L.P.   $ 1,000,000   *   48,780   *  
Zurich Institutional Benchmarks MASTER Fund c/o Alexandra Investment Mgmt LLC   $ 5,000,000   *   243,902   *  
Unnamed securityholders or any future transferees, pledgees, donees or successors of or from any such unnamed securityholder   $ 239,456,000   31.93%   11,680,799   *  
Total   $ 750,000,000   100%   36,585,300   2.62%  

*
Less than one percent (1%).

(1)
Assumes conversion of all of the holder's Notes at a conversion rate of 48.7804 shares of common stock (as adjusted for our 2-for-1 stock split effective May 12, 2004) per $1,000 principal amount at maturity of the Notes. This conversion rate is subject to adjustment as described under "Description of the Notes—Conversion Rights." As a result, the number of shares of common stock issuable upon conversion of the Notes may increase in the future. Excludes shares of common stock that may be issued by us upon the repurchase of the Notes and fractional shares. Holders will receive a cash adjustment for any fractional share amount resulting from conversion of the Notes, as described under "Description of the Notes—Conversion Rights."

(2)
Calculated based on Rule 13d-3(d)(i) of the Exchange Act, using 1,358,655,220 shares of common stock outstanding as of July 27, 2004. In calculating this amount for each holder, we treated as outstanding the number of shares of common stock issuable upon conversion of all of that holder's Notes, but we did not assume conversion of any other holder's Notes.

(3)
Salomon Brothers Asset Management, Inc. acts as discretionary investment advisor with respect to the following accounts that hold the indicated principal amounts of Notes: Citigroup Pension Fund CAP Arbitrage ($393,000); SB Diversified Arbitrage Strategies ($1,570,000); SB Enhanced Arbitrage Strategies ($413,000); GM Pension ($211,000); GM Veba ($632,000); SB Market Neutral Arbitrage ($628,000); SB Multi Strategy Arbitrage ($6,153,000).

S-4


VOTING/INVESTMENT CONTROL TABLE

Selling Securityholder

  Natural person or persons with voting or
dispositive power

AIG DKR SoundShore Opportunity Holding Fund Ltd.   Manan Rawal
AIG DKR SoundShore Strategic Holding Fund Ltd.   Manan Rawal
Alexandra Global Master Fund LTD   *
American AAdvantage Funds   Nick Calamos
Arbitex Master Fund, L.P.   Clark K. Hunt, Jonathan Bren and
Ken Tananbaum
Arpeggio Fund   *
Aventis Pension Master Trust   Nick Calamos
Bank Austria Cayman Islands, LTD   Alex Adair
Bank of America Pension Plan   *
Barclays Global Investors Ltd.   *
Bear, Stearns & Co. Inc.   *
Boilermaker—Blacksmith Pension Trust   Nick Calamos
BNP Paribas Equity Strategies, SNC   Christian Menestrier
CALAMOS® Convertible Fund—CALAMOS® Investment Trust   Nick Calamos
CALAMOS® Convertible Growth and Income Fund—CALAMOS® Investment Trust   Nick Calamos
CALAMOS® Convertible Portfolio—CALAMOS® Advisors Trust   Nick Calamos
CALAMOS® Global Convertible Fund—CALAMOS® Investment Trust   Nick Calamos
CEMEX Pension Plan   Nick Calamos
CGNU Life Fund   David Clott
City of Albany Pension Plan   Nick Calamos
City of Knoxville Pension System   Nick Calamos
Commercial Union Life Fund   David Clott
Consulting Group Capital Market Funds   *
CooperNeff Convertible Strategies (Cayman) Master Fund, LP   Christian Menestrier
Credit Suisse First Boston LLC   *
CSU Limited   *
DBAG London   Dan Azzi
Deep Rock & Co.   *
Delta Airlines Master Trust   Nick Calamos
Delta Pilots Disability and Survivorship Trust   Nick Calamos
Deutsche Bank Securities Inc.   *
Dodeca Fund, L.P.   Thomas J. Ray
Dorinco Reinsurance Company   Nick Calamos
Drake Offshore Master Fund Ltd.   *
Duckbill & Co.   *
Gasner Investors Holdings Ltd.   *
General Motors Welfare Benefit Trust   *
GLG Market Neutral Fund   *
GMAM Group Pension Trust   *
Goldman Sachs & Co. Profit Sharing Master Trust   Daniel S. Och
Guggenheim Portfolio Co. XV, LLC   Alex Adair
Highbridge International L.L.C.   *
IMF Convertible Fund   *
     

S-5


Inflective Convertible Opportunity Fund I, L.P.   Thomas J. Ray
JP Morgan Securities Inc.   *
KBC Convertible Arbitrage   Andy Preston
KBC Convertible Mac28, Ltd.   Andy Preston
KBC Financial Products [Cayman Islands] Ltd.   Luke Edwards
KBC Financial Products USA Inc.   Luke Edwards
Kettering Medical Center Funded Depreciation Account   Nick Calamos
Knoxville Utilities Board Retirement System   Nick Calamos
Lehman Brothers Inc.   *
Louisiana Workers' Compensation Corporation   Nick Calamos
Lyxor/Convertible Arbitrage Fund Limited   Christian Menestrier
Lyxor Master Fund   Clark K. Hunt, Jonathan Bren and Ken Tananbaum
Macomb County Employees' Retirement System   Nick Calamos
Man Convertible Bond Master Fund, Ltd.   J.T. Hansen and John Null
Melody IAM, Ltd.   Andy Preston
Nomura Securities International   *
Norwich Union Life & Pensions   David Clott
OZ Convertible Master Fund, Ltd.   Daniel S. Och
OZ MAC 13 Ltd.   Daniel S. Och
OZ Master Fund, Ltd.   Daniel S. Och
Pacific Life Insurance Company   Larry Card, Elaine Havens, Simon Lee and Rex Olson
Peoples Benefit Life Insurance Company Teamsters   *
Port Authority of Allegheny County Retirement and Disability Allowance Plan for the Employees Represented by Local 85 of the Amalgamated Transit Union   Nick Calamos
Prisma Foundation   Nick Calamos
Ramius Capital Group   Alex Adair
Ramius Master Fund, LTD   Alex Adair
Ramius Partners II, LP   Alex Adair
Ramius, LP   Alex Adair
RCG Baldwin, LP   Alex Adair
RCG Halifax Master Fund, LTD   Alex Adair
RCG Latitude Master Fund, LTD   Alex Adair
RCG Multi Strategy Master Fund, LTD   Alex Adair
Retail Clerks Pension Trust   *
Retail Clerks Pension Trust #2   *
Rhapsody Fund, L.P.   *
Salomon Brothers Asset Management, Inc.   *
SCI Endowment Care Common Trust Fund—First Union   Nick Calamos
SCI Endowment Care Common Trust Fund—National Fiduciary Services   Nick Calamos
SCI Endowment Care Common Trust Fund—Suntrust   Nick Calamos
Singlehedge US Convertible Arbitrage Fund   Christian Menestrier
South Dakota Retirement System   Chris Huisken and Matthew Clark
SPT   Nick Calamos
St. Albans Partners Ltd.   *
St. Thomas Trading, Ltd.   J.T. Hansen and John Null
     

S-6


Sturgeon Limited   Christian Menestrier
TCW Group, Inc.   *
The California Wellness Foundation   Nick Calamos
The Dow Chemical Company Employees' Retirement Plan   Nick Calamos
The Fondren Foundation   Nick Calamos
UBS A6 London Branch   *
UBS Securities LLC   *
Union Carbide Retirement Account   Nick Calamos
United Food and Commercial Workers Local 1262 and Employers Pension Fund   Nick Calamos
Univar USA Inc. Retirement Plan   Nick Calamos
Wachovia Bank National Association   *
Wachovia Capital Markets LLC   Eric Grant
White River Securities L.L.C.   *
WPG Convertible Arbitrage Overseas Master Fund   *
WPG MSA Convertible Arbitrage Fund   *
Xavex Convertible Arbitrage #5   Alex Adair
Yield Strategies Fund I, L.P.   *
Yield Strategies Fund II, L.P.   *
Zurich Institutional Benchmarks MASTER Fund c/o Alexandra Investment Mgmt LLC   *

*
The securityholder has informed Yahoo! that there is no natural person with voting or investment power over the respective Notes.

        Generally, only selling securityholders identified in the foregoing Selling Securityholders Table who beneficially own the securities set forth opposite their respective names may sell offered securities under the registration statement of which this prospectus forms a part. We may from time to time include additional selling securityholders in an amendment to this registration statement or a supplement to this prospectus.


The date of this prospectus supplement is July 29, 2004.

S-7




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SELLING SECURITYHOLDERS