ARM HOLDINGS PLC /UK (ARM) · Insider Trading (Form 4) SEC Filing

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-05-15 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: ARM HOLDINGS PLC /UK (ARM) CIK: 0001973239 --- Reporting Owner --- Name: Bartels Laura Kathleen CIK: 0002114104 Role: Officer (Chief Accounting Officer) --- Non-Derivative Transactions --- [Transaction #1] Security: Ordinary Shares Date: 2026-05-15 | Code: M (Exercise of derivative) Shares: +3,588 Shares Owned After: 23,654 | Ownership: D (Direct) Footnotes: [F1] Ordinary shares, nominal value 0.001 GBP per share ("Ordinary Shares"), are held in the form of American Depositary Shares ("ADSs"). Each ADS represents 1 Ordinary Share. [F2] This restricted stock unit ("RSU") award was granted on May 1, 2025, 28.5% of which vested on May 15, 2026, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. [F3] Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. [Transaction #2] Security: Ordinary Shares Date: 2026-05-15 | Code: M (Exercise of derivative) Shares: +862 Shares Owned After: 24,516 | Ownership: D (Direct) Footnotes: [F1] Ordinary shares, nominal value 0.001 GBP per share ("Ordinary Shares"), are held in the form of American Depositary Shares ("ADSs"). Each ADS represents 1 Ordinary Share. [F4] This RSU award was granted on May 13, 2024, 28.5% of which vested on May 15, 2025, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. [F3] Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. [Transaction #3] Security: Ordinary Shares Date: 2026-05-15 | Code: M (Exercise of derivative) Shares: +2,308 Shares Owned After: 26,824 | Ownership: D (Direct) Footnotes: [F1] Ordinary shares, nominal value 0.001 GBP per share ("Ordinary Shares"), are held in the form of American Depositary Shares ("ADSs"). Each ADS represents 1 Ordinary Share. [F5] This RSU award was granted on May 22, 2023, 28.5% of which vested on May 15, 2024, with quarterly vesting of 6.5% thereafter. The RSU award was fully vested on May 15, 2026. [F3] Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. [Transaction #4] Security: Ordinary Shares Date: 2026-05-15 | Code: F (Payment of exercise/tax) Shares: -3,383 | Price: $209.16 Total Value: $707,588.28 Shares Owned After: 23,441 | Ownership: D (Direct) Footnotes: [F1] Ordinary shares, nominal value 0.001 GBP per share ("Ordinary Shares"), are held in the form of American Depositary Shares ("ADSs"). Each ADS represents 1 Ordinary Share. [F6] Ordinary Shares withheld to satisfy tax withholding requirements on vesting of RSUs. --- Derivative Transactions --- [Transaction #1] Security: Restricted Stock Units Date: 2026-05-15 | Code: A (Grant or award) Shares: +16,645 | Price: $0.00 Shares Owned After: 38,440 | Ownership: D (Direct) Footnotes: [F3] Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. [F7] This RSU award was granted effective May 15, 2026, 28.5% will vest on May 15, 2027, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. [F7] This RSU award was granted effective May 15, 2026, 28.5% will vest on May 15, 2027, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. [Transaction #2] Security: Restricted Stock Units Date: 2026-05-15 | Code: A (Grant or award) Shares: +69,570 | Price: $0.00 Shares Owned After: 108,010 | Ownership: D (Direct) Footnotes: [F3] Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. [F8] This RSU award was granted effective May 15, 2026, 50% will vest on each of May 15, 2028 and May 15, 2029, subject to continued service to the Company. [F8] This RSU award was granted effective May 15, 2026, 50% will vest on each of May 15, 2028 and May 15, 2029, subject to continued service to the Company. [Transaction #3] Security: Restricted Stock Units Date: 2026-05-15 | Code: M (Exercise of derivative) Shares: -3,588 | Price: $0.00 Shares Owned After: 104,422 | Ownership: D (Direct) Footnotes: [F3] Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. [F2] This restricted stock unit ("RSU") award was granted on May 1, 2025, 28.5% of which vested on May 15, 2026, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. [F2] This restricted stock unit ("RSU") award was granted on May 1, 2025, 28.5% of which vested on May 15, 2026, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. [Transaction #4] Security: Restricted Stock Units Date: 2026-05-15 | Code: M (Exercise of derivative) Shares: -862 | Price: $0.00 Shares Owned After: 103,560 | Ownership: D (Direct) Footnotes: [F3] Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. [F4] This RSU award was granted on May 13, 2024, 28.5% of which vested on May 15, 2025, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. [F4] This RSU award was granted on May 13, 2024, 28.5% of which vested on May 15, 2025, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. [Transaction #5] Security: Restricted Stock Units Date: 2026-05-15 | Code: M (Exercise of derivative) Shares: -2,308 | Price: $0.00 Shares Owned After: 101,252 | Ownership: D (Direct) Footnotes: [F3] Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. [F5] This RSU award was granted on May 22, 2023, 28.5% of which vested on May 15, 2024, with quarterly vesting of 6.5% thereafter. The RSU award was fully vested on May 15, 2026. [F5] This RSU award was granted on May 22, 2023, 28.5% of which vested on May 15, 2024, with quarterly vesting of 6.5% thereafter. The RSU award was fully vested on May 15, 2026. --- Footnotes (Complete Index) --- F1: Ordinary shares, nominal value 0.001 GBP per share ("Ordinary Shares"), are held in the form of American Depositary Shares ("ADSs"). Each ADS represents 1 Ordinary Share. F2: This restricted stock unit ("RSU") award was granted on May 1, 2025, 28.5% of which vested on May 15, 2026, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. F3: Each RSU represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. F4: This RSU award was granted on May 13, 2024, 28.5% of which vested on May 15, 2025, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. F5: This RSU award was granted on May 22, 2023, 28.5% of which vested on May 15, 2024, with quarterly vesting of 6.5% thereafter. The RSU award was fully vested on May 15, 2026. F6: Ordinary Shares withheld to satisfy tax withholding requirements on vesting of RSUs. F7: This RSU award was granted effective May 15, 2026, 28.5% will vest on May 15, 2027, with quarterly vesting of 6.5% thereafter, subject to continued service to the Company. F8: This RSU award was granted effective May 15, 2026, 50% will vest on each of May 15, 2028 and May 15, 2029, subject to continued service to the Company. --- Signature --- /s/ /s/ George Kanelos, as Attorney-in-Fact for Laura Kathleen Bartels (2026-05-19)