[Form 4] WESTERN DIGITAL CORP Insider Trading Activity

Rhea-AI Filing Summary

Western Digital Corp. director Matthew E. Massengill reported a series of pre‑planned stock sales on February 5, 2026 by a family trust associated with him. The trust sold multiple blocks of Western Digital common stock, including 7,000 shares at $258.6719 and 5,987 shares at $260.5707, under a Rule 10b5‑1 trading plan adopted on November 6, 2025.

After these trust sales, Massengill reported 28,897 shares of Western Digital common stock held directly and another 500 shares held indirectly through an IRA, while the family trust reported no remaining shares.

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).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

MASSENGILL MATTHEW E

(Last) (First) (Middle)

C/O WESTERN DIGITAL CORPORATION

5601 GREAT OAKS PARKWAY

(Street)

SAN JOSE CA 95119

(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
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
02/05/2026

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	02/05/2026		S(1)		2,600	D	$256.6312(2)	34,326	I	By Family Trust
Common Stock	02/05/2026		S(1)		4,411	D	$257.6851(3)	29,915	I	By Family Trust
Common Stock	02/05/2026		S(1)		7,000	D	$258.6719(4)	22,915	I	By Family Trust
Common Stock	02/05/2026		S(1)		4,915	D	$259.5923(5)	18,000	I	By Family Trust
Common Stock	02/05/2026		S(1)		5,987	D	$260.5707(6)	12,013	I	By Family Trust
Common Stock	02/05/2026		S(1)		3,597	D	$261.7077(7)	8,416	I	By Family Trust
Common Stock	02/05/2026		S(1)		2,300	D	$262.7678(8)	6,116	I	By Family Trust
Common Stock	02/05/2026		S(1)		2,600	D	$264.0112(9)	3,516	I	By Family Trust
Common Stock	02/05/2026		S(1)		2,200	D	$264.9908(10)	1,316	I	By Family Trust
Common Stock	02/05/2026		S(1)		916	D	$265.9172(11)	400	I	By Family Trust
Common Stock	02/05/2026		S(1)		400	D	$268.055(12)	0	I	By Family Trust
Common Stock								28,897	D
Common Stock								500	I	by IRA

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

Explanation of Responses:

1. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on November 6, 2025.

2. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $256.12 to a high of $257.09. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

3. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $257.14 to a high of $258.13. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

4. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $258.14 to a high of $259.13. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

5. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $259.15 to a high of $260.12. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

6. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $260.15 to a high of $261.05. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

7. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $261.19 to a high of $262.18. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

8. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $262.21 to a high of $263.14. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

9. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $263.40 to a high of $264.38. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

10. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $264.54 to a high of $265.51. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

11. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $265.57 to a high of $266.27. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

12. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $267.58 to a high of $268.53. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.

	By: /s/ Sandra Garcia Attorney-in-Fact For: Matthew E. Massengill	02/06/2026
	** 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).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction did Western Digital (WDC) disclose for Matthew Massengill?

Western Digital reported that a family trust associated with director Matthew E. Massengill sold multiple blocks of common stock on February 5, 2026. The transactions were reported on Form 4 and reflect indirect ownership changes rather than sales from his directly held shares.

Were the Western Digital (WDC) insider sales under a 10b5-1 trading plan?

Yes. The filing states the Western Digital sales were made under a Rule 10b5-1 trading plan adopted by the reporting person on November 6, 2025. Such plans pre-schedule trades, helping separate personal trading decisions from later market-moving information.

How many Western Digital (WDC) shares did the family trust sell and at what prices?

The Form 4 lists several trust sales, including 7,000 shares at $258.6719 and 5,987 shares at $260.5707. Each line shows weighted-average prices with underlying trades executed in narrow price ranges disclosed in the accompanying footnotes.

What Western Digital (WDC) shares does Matthew Massengill report owning after the transactions?

After the reported sales, Massengill reports 28,897 Western Digital common shares held directly and 500 shares held indirectly through an IRA. The family trust’s line in the table shows zero shares remaining following its February 5, 2026 transactions.

Were derivative securities involved in this Western Digital (WDC) Form 4 filing?

No derivative securities transactions are listed. The Form 4’s derivative securities table is blank, and all reported activity involves non-derivative Western Digital common stock held indirectly by a family trust, plus updated direct and IRA share holdings.

Does the Western Digital (WDC) Form 4 show ongoing direct ownership by the director?

Yes. Despite the trust sales, the director continues to hold Western Digital shares directly. The filing shows 28,897 common shares held directly in his name and an additional 500 shares held indirectly through an IRA account as of the reported date.