Arm

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-09-14 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: ARM HOLDINGS PLC /UK (ARM) CIK: 0001973239 --- Reporting Owner --- Name: Abbey William CIK: 0001945497 Role: Officer (Chief Commercial Officer) --- Derivative Transactions --- [Transaction #1] Security: Restricted Stock Units Date: 2026-09-14 | Code: A (Grant or award) Shares: +17,288 | Price: $0.00 Shares Owned After: 65,270 | Ownership: D (Direct) Footnotes: [F1] Each restricted stock unit ("RSU") represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. [F2] This RSU award was granted effective September 14, 2026. 50% will vest on each of August 15, 2028 and August 15, 2029, subject to continued service to Arm Holdings plc. [F2] This RSU award was granted effective September 14, 2026. 50% will vest on each of August 15, 2028 and August 15, 2029, subject to continued service to Arm Holdings plc. [F3] 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. --- Footnotes (Complete Index) --- F1: Each restricted stock unit ("RSU") represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. F2: This RSU award was granted effective September 14, 2026. 50% will vest on each of August 15, 2028 and August 15, 2029, subject to continued service to Arm Holdings plc. F3: 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. --- Signature --- /s/ /s/ George Kanelos, as Attorney-in-Fact for William Abbey (2026-09-16)