TREGILLIS CYNTHIA L (Chief Legal Officer & Corp Sec) sold 0.3% of their position (438.00 shares) of WESTERN DIGITAL CORP on the open market

Open‑market sale worth $123.7K — a minor trim. Review remaining holdings and any 10b5‑1 plan disclosures.

S · 2 sales

TREGILLIS CYNTHIA L

Filed: 2/24/2026ACC: 0001266824-26-000021

InsiderTREGILLIS CYNTHIA LCIK 2057088

→

IssuerWESTERN DIGITAL CORPCIK 106040

Officer· Chief Legal Officer & Corp Sec

Since Mar 2026

-1.79K

Net shares

Net seller

$510.0K

Total sold

Open market trades

0B · 2S

Total transactions

12.00 acquired · 1.80K disposed

Non-Derivative Transactions6

Common Stock

Direct

M · Option Exercise

+3.00

Price / share

—

Trade value

—

% of position

0.0%

2/20/2026

136.54K→136.54K

Common Stock

Direct

F · Tax Withholding

−244.00

Price / share

$285.52

Trade value

$69.67K

% of position

0.2%

2/20/2026

136.54K→136.30K

Common Stock

Direct

M · Option Exercise

+9.00

Price / share

—

Trade value

—

% of position

0.0%

2/21/2026

136.30K→136.31K

Common Stock

Direct

F · Tax Withholding

−1.11K

Price / share

$285.52

Trade value

$316.64K

% of position

0.8%

2/21/2026

136.31K→135.20K

Common Stock

Direct

S · Sale

−130.00

Price / share

$283.83

Trade value

$36.90K

% of position

0.1%

2/23/2026

135.20K→135.07K

Common Stock

Direct

S · Sale

−308.00

Price / share

$281.70

Trade value

$86.76K

% of position

0.2%

2/24/2026

135.07K→134.76K

Total

Net shares

−1.78K

Net value

-$509.97K

Security	Date	Type	Shares	Price / Share	Trade Value	% of Position	Held Before	Held After
Common Stock Direct	2/20/2026	M · Option Exercise	+3.00	—	—	0.0%	136.54K	136.54K
Common Stock Direct	2/20/2026	F · Tax Withholding	−244.00	$285.52	$69.67K	0.2%	136.54K	136.30K
Common Stock Direct	2/21/2026	M · Option Exercise	+9.00	—	—	0.0%	136.30K	136.31K
Common Stock Direct	2/21/2026	F · Tax Withholding	−1.11K	$285.52	$316.64K	0.8%	136.31K	135.20K
Common Stock Direct	2/23/2026	S · Sale	−130.00	$283.83	$36.90K	0.1%	135.20K	135.07K
Common Stock Direct	2/24/2026	S · Sale	−308.00	$281.70	$86.76K	0.2%	135.07K	134.76K
Total			−1.78K		-$509.97K

Derivative Transactions2

Dividend Equivalent Rights

Direct

M · Option Exercise

Converts to

Common Stock

3.23 shares

−3.23

Strike price

Held after

344.23

Exercisable

—

2/20/2026

Dividend Equivalent Rights

Direct

M · Option Exercise

Converts to

Common Stock

9.44 shares

−9.44

Strike price

Held after

334.79

Exercisable

—

2/21/2026

Security	Converts To	Date	Type	Shares	Strike Price	Exercisable	Held After
Dividend Equivalent Rights Direct	Common Stock3.23 shares	2/20/2026	M · Option Exercise	−3.23		—	344.23
Dividend Equivalent Rights Direct	Common Stock9.44 shares	2/21/2026	M · Option Exercise	−9.44		—	334.79