WILLIAM D. MOSLEY - 02 Jan 2026 Form 4 Insider Report for Seagate Technology Holdings plc (STX)

Signature
/s/ Louis J. Thorson, Attorney-in-Fact for William D. Mosley
Issuer symbol
STX
Transactions as of
02 Jan 2026
Net transactions value
-$5,711,245
Form type
4
Filing time
06 Jan 2026, 17:06:29 UTC
Previous filing
12 Dec 2025
Next filing
03 Feb 2026

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
MOSLEY WILLIAM D CEO, Director SEAGATE TECHNOLOGY HOLDINGS PLC, 47488 KATO ROAD, FREMONT /s/ Louis J. Thorson, Attorney-in-Fact for William D. Mosley 06 Jan 2026 0001388390

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction STX Ordinary Shares Sale $224,875 -800 -0.18% $281.09 449,095 02 Jan 2026 Direct F1, F2
transaction STX Ordinary Shares Sale $564,173 -2,000 -0.45% $282.09 447,095 02 Jan 2026 Direct F3
transaction STX Ordinary Shares Sale $453,154 -1,600 -0.36% $283.22 445,495 02 Jan 2026 Direct F4
transaction STX Ordinary Shares Sale $511,352 -1,800 -0.4% $284.08 443,695 02 Jan 2026 Direct F5
transaction STX Ordinary Shares Sale $771,550 -2,705 -0.61% $285.23 440,990 02 Jan 2026 Direct F6
transaction STX Ordinary Shares Sale $1,026,755 -3,586 -0.81% $286.32 437,404 02 Jan 2026 Direct F7
transaction STX Ordinary Shares Sale $1,438,955 -5,009 -1.1% $287.27 432,395 02 Jan 2026 Direct F8
transaction STX Ordinary Shares Sale $604,821 -2,100 -0.49% $288.01 430,295 02 Jan 2026 Direct F9
transaction STX Ordinary Shares Sale $115,611 -400 -0.09% $289.03 429,895 02 Jan 2026 Direct F10
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Buy Plan / Sale Plan: These are also open market purchases/sales of shares, but in this case the transaction is part of a trading plan. Rule 10b5-1 allows insiders to setup a trading plan to buy/sell stocks over a certain period of time. Since the purchases/sales are predetermined, this protects the insiders from violating insider trading law.

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).

Explanation of Responses:

Id Content
F1 These Ordinary Shares were sold under a Rule 10b5-1 trading plan adopted by the Reporting Person February 20, 2025.
F2 These Ordinary Shares were sold in multiple trades at prices ranging from $280.66 to $281.52. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.
F3 These Ordinary Shares were sold in multiple trades at prices ranging from $281.66 to $282.62. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.
F4 These Ordinary Shares were sold in multiple trades at prices ranging from $282.69 to $283.59. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.
F5 These Ordinary Shares were sold in multiple trades at prices ranging from $283.69 to $284.53. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.
F6 These Ordinary Shares were sold in multiple trades at prices ranging from $284.70 to $285.68. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.
F7 These Ordinary Shares were sold in multiple trades at prices ranging from $285.71 to $286.69. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.
F8 These Ordinary Shares were sold in multiple trades at prices ranging from $286.71 to $287.67. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.
F9 These Ordinary Shares were sold in multiple trades at prices ranging from $287.72 to $288.66. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.
F10 These Ordinary Shares were sold in multiple trades at prices ranging from $288.74 to $289.25. The price reported above reflects the weighted average sale price. The Reporting Person hereby undertakes to provide upon request to the SEC staff, the Issuer, or a security holder of the Issuer, full information regarding the number of shares and prices at which the transaction was effected.