Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
MASSENGILL MATTHEW E
  2. Issuer Name and Ticker or Trading Symbol
WESTERN DIGITAL CORP [WDC]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chairman and CEO
(Last)
(First)
(Middle)
C/O WESTERN DIGITAL CORPORATION, 20511 LAKE FOREST DRIVE
3. Date of Earliest Transaction (Month/Day/Year)
12/02/2004
(Street)

LAKE FOREST, CA 92630-7741
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 12/02/2004   M   250,000 A $ 2.1 723,106 D  
Common Stock 12/02/2004   M   206,250 A $ 3.85 929,356 D  
Common Stock 12/02/2004   M   225,229 A $ 4.5625 1,154,585 D  
Common Stock 12/02/2004   S   929 D $ 10.32 1,153,656 D  
Common Stock 12/02/2004   S   11,613 D $ 10.33 1,142,043 D  
Common Stock 12/02/2004   S   54,443 D $ 10.34 1,087,600 D  
Common Stock 12/02/2004   S   7,525 D $ 10.41 1,080,075 D  
Common Stock 12/02/2004   S   132,577 D $ 10.4 947,498 D  
Common Stock 12/02/2004   S   23,691 D $ 10.38 923,807 D  
Common Stock 12/02/2004   S   20,254 D $ 10.37 903,553 D  
Common Stock 12/02/2004   S   111,766 D $ 10.39 791,787 D  
Common Stock 12/02/2004   S   131,091 D $ 10.35 660,696 D  
Common Stock 12/02/2004   S   108,143 D $ 10.36 552,553 D  
Common Stock 12/02/2004   S   12,449 D $ 10.31 540,104 D  
Common Stock 12/02/2004   S   200,348 D $ 10.3 339,756 D  
Common Stock               4,008 I by Trust 401(K)

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Employee Stock Option (right to buy) $ 2.1 12/02/2004   M     250,000 03/26/2002(1) 09/26/2011 Common Stock 250,000 $ 0 0 D  
Employee Stock Option (right to buy) $ 3.85 12/02/2004   M     206,250 03/23/2003(2) 09/23/2012 Common Stock 206,250 $ 0 100,000 D  
Employee Stock Option (right to buy) $ 4.5625 12/02/2004   M     225,229 01/12/2001(3) 01/12/2010 Common Stock 225,229 $ 0 18,521 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
MASSENGILL MATTHEW E
C/O WESTERN DIGITAL CORPORATION
20511 LAKE FOREST DRIVE
LAKE FOREST, CA 92630-7741
  X     Chairman and CEO  

Signatures

 By: /s/ Sandra Garcia Attorney-in-Fact For: Matthew E. Massengill   12/06/2004
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) The option vested 25% 6 months from the grant date of 9/26/2001, and the remaining 75% vested in three equal installments on September 26, 2002, 2003 and 2004.
(2) The option vested 25% 6 months from the grant date of 9/23/2002, 50% vested in two equal installments on September 23, 2003 and 2004, and the final 25% will vest on September 23, 2005.
(3) The option vested 25% 12 months from the grant date of 1/12/2000 and 6.25% at the end of each three-month period thereafter.

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