Western Digital (WDC) legal chief sells 9,324 shares under 10b5-1 plan

Rhea-AI Filing Summary

WESTERN DIGITAL CORP Chief Legal Officer and Corporate Secretary Cynthia L. Tregillis reported multiple transactions in the company’s common stock. She sold a total of 9,324 shares in open-market sales, including 777 shares at $257.91 per share and 8,547 shares at a weighted average price of $269.2156 per share, under a Rule 10b5-1 trading plan adopted on May 23, 2025.

She also acquired 23 shares of common stock upon the conversion of 23.8133 dividend equivalent rights tied to restricted stock units, and 2,798 shares were withheld at $250.61 per share to cover tax obligations related to vesting. After these transactions, she directly held 121,682 shares of common stock and 304.413 dividend equivalent rights.

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^*

Tregillis Cynthia L

(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)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Legal Officer & Corp Sec

3. Date of Earliest Transaction (Month/Day/Year)
03/03/2026

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	03/03/2026		M		23(1)	A	$0.0	133,804	D
Common Stock	03/03/2026		F		2,798(2)	D	$250.61	131,006	D
Common Stock	03/04/2026		S(3)		777	D	$257.91	130,229	D
Common Stock	03/04/2026		S		8,547	D	$269.2156(4)	121,682	D

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
Dividend Equivalent Rights	(1)	03/03/2026		M			23.8133	(1)	(1)	Common Stock	23.8133	$0.0	304.413	D

Explanation of Responses:

1. The dividend equivalent rights were converted into, and paid in the form of, shares of the Issuer's common stock on a one-for-one basis in connection with the vesting of restricted stock units to which the dividend equivalent rights relate. A cash amount was also paid to the holder to settle a fractional dividend equivalent right.

2. Payment of tax obligation by withholding securities incident to the vesting of securities in accordance with Rule 16b-3(e).

3. The sales reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on May 23, 2025.

4. Represents the weighted average sale price per share. These shares were sold in multiple transactions at prices ranging from a low of $269.17 to a high of $269.2201. 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: Cynthia Tregillis	03/05/2026
	** 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 transactions did WDC executive Cynthia Tregillis report on this Form 4?

Cynthia Tregillis reported open-market sales of 9,324 Western Digital shares, derivative-related acquisitions, and tax-withholding dispositions. The filing details sales, dividend equivalent right conversions into common stock, and shares withheld to satisfy tax obligations linked to vesting restricted stock units.

How many Western Digital (WDC) shares did Cynthia Tregillis sell and at what prices?

She sold 9,324 shares of Western Digital common stock in two open-market transactions. These included 777 shares at $257.91 per share and 8,547 shares at a weighted average price of $269.2156 per share, as disclosed in the Form 4.

Was the Western Digital (WDC) insider sale by Cynthia Tregillis under a 10b5-1 plan?

Yes. The Form 4 states the sales were effected under a Rule 10b5-1 trading plan adopted by Cynthia Tregillis on May 23, 2025. Such pre-arranged plans allow insiders to schedule trades in advance under predetermined conditions.

How many Western Digital (WDC) shares does Cynthia Tregillis hold after these transactions?

Following the reported trades, Cynthia Tregillis directly held 121,682 shares of Western Digital common stock. She also held 304.413 dividend equivalent rights, which relate to restricted stock units and can convert into additional shares under the plan terms.

What were the tax-withholding transactions reported for Western Digital (WDC) stock?

The Form 4 discloses a tax-withholding disposition of 2,798 shares of Western Digital common stock at $250.61 per share. These shares were withheld to satisfy tax obligations arising from the vesting of equity awards, consistent with Rule 16b-3(e).

How were dividend equivalent rights handled in this Western Digital (WDC) Form 4?

Dividend equivalent rights were converted one-for-one into 23 shares of common stock in connection with restricted stock unit vesting. The filing notes a small cash payment also settled a fractional dividend equivalent right associated with these awards.