SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* MASSENGILL MATTHEW E (Last) (First) (Middle) C/O WESTERN DIGITAL CORPORATION 20511 LAKE FOREST DRIVE (Street) LAKE FOREST CA 92630-7741 (City) (State) (Zip)	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 of the Board
	3. Date of Earliest Transaction (Month/Day/Year) 01/31/2006
	4. If Amendment, Date of 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

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	01/31/2006		M		121,000	A	$10.21	671,950	D
Common Stock	01/31/2006		M		85,400	A	$10.25	757,350	D
Common Stock	01/31/2006		M		10,000	A	$10.25	767,350	D
Common Stock	01/31/2006		M		6,784	A	$12.25	774,134	D
Common Stock	01/31/2006		M		40,000	A	$12.875	814,134	D
Common Stock	01/31/2006		M		11,500	A	$11.875	825,634	D
Common Stock	01/31/2006		S		12,000	D	$21.75	813,634	D
Common Stock	01/31/2006		S		1,700	D	$21.76	811,934	D
Common Stock	01/31/2006		S		38,300	D	$21.77	773,634	D
Common Stock	01/31/2006		S		8,800	D	$21.78	764,834	D
Common Stock	01/31/2006		S		15,300	D	$21.79	749,534	D
Common Stock	01/31/2006		S		71,000	D	$21.8	678,534	D
Common Stock	01/31/2006		S		16,200	D	$21.81	662,334	D
Common Stock	01/31/2006		S		40,700	D	$21.82	621,634	D
Common Stock	01/31/2006		S		32,084	D	$21.83	589,550	D
Common Stock	01/31/2006		S		3,900	D	$21.84	585,650	D
Common Stock	01/31/2006		S		17,300	D	$21.85	568,350	D
Common Stock	01/31/2006		S		900	D	$21.86	567,450	D
Common Stock	01/31/2006		S		800	D	$21.87	566,650	D
Common Stock	01/31/2006		S		6,800	D	$21.88	559,850	D
Common Stock	01/31/2006		S		7,500	D	$21.89	552,350	D
Common Stock	01/31/2006		S		1,400	D	$21.9	550,950	D
Common Stock								4,008	I	by Trust 401(K)

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 Securities Underlying Derivative Security (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: 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)	$10.21	01/31/2006		M			121,000	01/20/2006(1)	01/20/2015	Common Stock	121,000	$0	191,500	D
Employee Stock Option (right to buy)	$10.25	01/31/2006		M			85,400	09/09/2000(2)	09/09/2008	Common Stock	85,400	$0	10,000	D
Employee Stock Option (right to buy)	$10.25	01/31/2006		M			10,000	09/09/1999(3)	09/09/2008	Common Stock	10,000	$0	0	D
Employee Stock Option (right to buy)	$11.875	01/31/2006		M			11,500	07/24/1997(3)	07/24/2006	Common Stock	11,500	$0	4,500	D
Employee Stock Option (right to buy)	$12.25	01/31/2006		M			6,784	08/06/2005(4)	08/06/2008	Common Stock	6,784	$0	0	D
Employee Stock Option (right to buy)	$12.875	01/31/2006		M			40,000	11/17/1999(3)	11/17/2008	Common Stock	40,000	$0	0	D

Explanation of Responses:

1. A total of 125,000 shares vested one year from the grant date of 1/20/2005. An additional 93,750 shares subject to the option will vest in substantially equal installments at the end of each three-month period until 10/20/2006. The remaining shares subject to the option will vest on 1/1/2007.

2. The option vested 5% 2 years from the grant date, 15% 3 years from the grant date, 30% 4 years from the grant date, and the final 50% 5 years from the grant date.

3. The option vested 25% on the first anniversary of the grant date and 6.25% at the end of each three-month period thereafter.

4. The option vested 100% seven years from the grant date.

	By: /s/ Sandra Garcia Attorney-in-Fact For: Matthew E. Massengill	02/01/2006
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* 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).
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