Seagate Technology (STX)

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-03-02 10b5-1 Pre-arranged Plan: Yes --- Issuer --- Name: Seagate Technology Holdings plc (STX) CIK: 0001137789 --- Reporting Owner --- Name: MOSLEY WILLIAM D CIK: 0001388390 Role: Director, Officer (CEO) --- Non-Derivative Transactions --- [Transaction #1] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -874 | Price: $375.84 Total Value: $328,486.00 Shares Owned After: 415,023 | Ownership: D (Direct) Footnotes: [F1] All transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on February 20, 2025. [F2] These Ordinary Shares were sold in multiple trades at prices ranging from $375.25 to $376.13. 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. [Transaction #2] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -326 | Price: $376.69 Total Value: $122,799.64 Shares Owned After: 414,697 | Ownership: D (Direct) Footnotes: [F3] These Ordinary Shares were sold in multiple trades at prices ranging from $376.37 to $376.91. 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. [Transaction #3] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -800 | Price: $377.95 Total Value: $302,359.04 Shares Owned After: 413,897 | Ownership: D (Direct) Footnotes: [F4] These Ordinary Shares were sold in multiple trades at prices ranging from $377.45 to $378.37. 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. [Transaction #4] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -1,740 | Price: $379.23 Total Value: $659,861.77 Shares Owned After: 412,157 | Ownership: D (Direct) Footnotes: [F5] These Ordinary Shares were sold in multiple trades at prices ranging from $378.69 to $379.68. 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. [Transaction #5] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -1,260 | Price: $380.42 Total Value: $479,331.22 Shares Owned After: 410,897 | Ownership: D (Direct) Footnotes: [F6] These Ordinary Shares were sold in multiple trades at prices ranging from $379.89 to $380.83. 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. [Transaction #6] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -800 | Price: $381.51 Total Value: $305,210.00 Shares Owned After: 410,097 | Ownership: D (Direct) Footnotes: [F7] These Ordinary Shares were sold in multiple trades at prices ranging from $380.95 to $381.92. 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. [Transaction #7] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -3,500 | Price: $382.41 Total Value: $1,338,437.45 Shares Owned After: 406,597 | Ownership: D (Direct) Footnotes: [F8] These Ordinary Shares were sold in multiple trades at prices ranging from $381.99 to $382.98. 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. [Transaction #8] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -2,700 | Price: $383.49 Total Value: $1,035,423.00 Shares Owned After: 403,897 | Ownership: D (Direct) Footnotes: [F9] These Ordinary Shares were sold in multiple trades at prices ranging from $383.05 to $384.00. 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. [Transaction #9] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -2,700 | Price: $384.51 Total Value: $1,038,175.11 Shares Owned After: 401,197 | Ownership: D (Direct) Footnotes: [F10] These Ordinary Shares were sold in multiple trades at prices ranging from $384.05 to $384.93. 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. [Transaction #10] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -1,200 | Price: $385.39 Total Value: $462,467.04 Shares Owned After: 399,997 | Ownership: D (Direct) Footnotes: [F11] These Ordinary Shares were sold in multiple trades at prices ranging from $385.11 to $386.02. 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. [Transaction #11] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -300 | Price: $387.54 Total Value: $116,262.99 Shares Owned After: 399,697 | Ownership: D (Direct) Footnotes: [F12] These Ordinary Shares were sold in multiple trades at prices ranging from $387.35 to $387.64. 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. [Transaction #12] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -300 | Price: $390.02 Total Value: $117,005.01 Shares Owned After: 399,397 | Ownership: D (Direct) Footnotes: [F13] These Ordinary Shares were sold in multiple trades at prices ranging from $389.61 to $390.49. 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. [Transaction #13] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -500 | Price: $392.09 Total Value: $196,044.00 Shares Owned After: 398,897 | Ownership: D (Direct) Footnotes: [F14] These Ordinary Shares were sold in multiple trades at prices ranging from $391.68 to $392.58. 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. [Transaction #14] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -500 | Price: $393.33 Total Value: $196,666.00 Shares Owned After: 398,397 | Ownership: D (Direct) Footnotes: [F15] These Ordinary Shares were sold in multiple trades at prices ranging from $392.95 to $393.73. 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. [Transaction #15] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -600 | Price: $394.75 Total Value: $236,851.02 Shares Owned After: 397,797 | Ownership: D (Direct) Footnotes: [F16] These Ordinary Shares were sold in multiple trades at prices ranging from $394.26 to $395.19. 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. [Transaction #16] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -800 | Price: $396.42 Total Value: $317,132.00 Shares Owned After: 396,997 | Ownership: D (Direct) Footnotes: [F17] These Ordinary Shares were sold in multiple trades at prices ranging from $395.77 to $396.74. 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. [Transaction #17] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -200 | Price: $397.61 Total Value: $79,521.00 Shares Owned After: 396,797 | Ownership: D (Direct) Footnotes: [F18] These Ordinary Shares were sold in multiple trades at prices ranging from $397.51 to $397.70. 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. [Transaction #18] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -100 | Price: $400.27 Total Value: $40,027.00 Shares Owned After: 396,697 | Ownership: D (Direct) [Transaction #19] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -300 | Price: $402.09 Total Value: $120,627.00 Shares Owned After: 396,397 | Ownership: D (Direct) Footnotes: [F19] These Ordinary Shares were sold in multiple trades at prices ranging from $401.89 to $402.43. 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. [Transaction #20] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -100 | Price: $403.05 Total Value: $40,305.00 Shares Owned After: 396,297 | Ownership: D (Direct) [Transaction #21] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -300 | Price: $405.02 Total Value: $121,505.01 Shares Owned After: 395,997 | Ownership: D (Direct) Footnotes: [F20] These Ordinary Shares were sold in multiple trades at prices ranging from $404.64 to $405.36. 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. [Transaction #22] Security: Ordinary Shares Date: 2026-03-02 | Code: S (Open market sale) Shares: -100 | Price: $407.66 Total Value: $40,766.00 Shares Owned After: 395,897 | Ownership: D (Direct) --- Footnotes (Complete Index) --- F1: All transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the Reporting Person on February 20, 2025. F10: These Ordinary Shares were sold in multiple trades at prices ranging from $384.05 to $384.93. 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. F11: These Ordinary Shares were sold in multiple trades at prices ranging from $385.11 to $386.02. 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. F12: These Ordinary Shares were sold in multiple trades at prices ranging from $387.35 to $387.64. 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. F13: These Ordinary Shares were sold in multiple trades at prices ranging from $389.61 to $390.49. 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. F14: These Ordinary Shares were sold in multiple trades at prices ranging from $391.68 to $392.58. 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. F15: These Ordinary Shares were sold in multiple trades at prices ranging from $392.95 to $393.73. 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. F16: These Ordinary Shares were sold in multiple trades at prices ranging from $394.26 to $395.19. 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. F17: These Ordinary Shares were sold in multiple trades at prices ranging from $395.77 to $396.74. 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. F18: These Ordinary Shares were sold in multiple trades at prices ranging from $397.51 to $397.70. 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. F19: These Ordinary Shares were sold in multiple trades at prices ranging from $401.89 to $402.43. 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. F2: These Ordinary Shares were sold in multiple trades at prices ranging from $375.25 to $376.13. 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. F20: These Ordinary Shares were sold in multiple trades at prices ranging from $404.64 to $405.36. 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 $376.37 to $376.91. 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 $377.45 to $378.37. 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 $378.69 to $379.68. 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. F6: These Ordinary Shares were sold in multiple trades at prices ranging from $379.89 to $380.83. 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 $380.95 to $381.92. 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 $381.99 to $382.98. 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 $383.05 to $384.00. 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. --- Signature --- /s/ /s/ Louis J. Thorson, Attorney-in-Fact for William D. Mosley (2026-03-03)