Arm

=== SEC Form 4 — Statement of Changes in Beneficial Ownership === Document Type: 4 Period of Report: 2026-09-09 10b5-1 Pre-arranged Plan: No --- Issuer --- Name: ARM HOLDINGS PLC /UK (ARM) CIK: 0001973239 --- Reporting Owner --- Name: Haas Rene A. CIK: 0001998912 Role: Director, Officer (Chief Executive Officer) --- Non-Derivative Transactions --- [Transaction #1] Security: Ordinary Shares Date: 2026-08-31 | Code: A (Grant or award) Shares: +64 | Price: $108.33 Total Value: $6,933.12 Shares Owned After: 338,666 | 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] Acquired under the Arm Holdings plc Employee Stock Purchase Plan on August 31, 2026. [F3] The number of shares held reflects the transfer, on September 9, 2026, of 57,405 Ordinary Shares from the Reporting Person to a grantor retained annuity trust, of which the Reporting Person serves as trustee. --- Derivative Transactions --- [Transaction #1] Security: Restricted Stock Units Date: 2026-09-09 | Code: A (Grant or award) Shares: +425,000 | Price: $0.00 Shares Owned After: 425,000 | Ownership: D (Direct) Footnotes: [F5] Each restricted stock unit ("RSU") represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. [F6] This RSU award was granted in May 2026, subject to shareholder approval, which was obtained on September 9, 2026. This award has three tranches, each contingent on achieving market capitalization milestones: $1.0 trillion by March 31, 2029, $1.5 trillion by March 31, 2030, and $2.0 trillion by March 31, 2031. 25% of the VCP award is tied to each interim milestone, with the remaining 50% tied to the final milestone. If an interim milestone is not achieved within the specified timeframe, the associated portion will roll forward and remain eligible for vesting upon achievement of a subsequent milestone. Achievement of the milestones will be determined based on the rolling average closing price over any 60-day period prior to the relevant milestone date. If a milestone is achieved, vesting of the associated RSUs will occur on April 1, two years following the relevant milestone date, subject to continued employment. [F6] This RSU award was granted in May 2026, subject to shareholder approval, which was obtained on September 9, 2026. This award has three tranches, each contingent on achieving market capitalization milestones: $1.0 trillion by March 31, 2029, $1.5 trillion by March 31, 2030, and $2.0 trillion by March 31, 2031. 25% of the VCP award is tied to each interim milestone, with the remaining 50% tied to the final milestone. If an interim milestone is not achieved within the specified timeframe, the associated portion will roll forward and remain eligible for vesting upon achievement of a subsequent milestone. Achievement of the milestones will be determined based on the rolling average closing price over any 60-day period prior to the relevant milestone date. If a milestone is achieved, vesting of the associated RSUs will occur on April 1, two years following the relevant milestone date, subject to continued employment. --- Holdings --- [Holding #1] Security: Ordinary Shares Ownership: I (Indirect) 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. [F3] The number of shares held reflects the transfer, on September 9, 2026, of 57,405 Ordinary Shares from the Reporting Person to a grantor retained annuity trust, of which the Reporting Person serves as trustee. [F4] Grantor retained annuity trust is for the benefit of the Reporting Person. --- 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: Acquired under the Arm Holdings plc Employee Stock Purchase Plan on August 31, 2026. F3: The number of shares held reflects the transfer, on September 9, 2026, of 57,405 Ordinary Shares from the Reporting Person to a grantor retained annuity trust, of which the Reporting Person serves as trustee. F4: Grantor retained annuity trust is for the benefit of the Reporting Person. F5: Each restricted stock unit ("RSU") represents the right to receive, following vesting, 1 Ordinary Share held in the form of an ADS. F6: This RSU award was granted in May 2026, subject to shareholder approval, which was obtained on September 9, 2026. This award has three tranches, each contingent on achieving market capitalization milestones: $1.0 trillion by March 31, 2029, $1.5 trillion by March 31, 2030, and $2.0 trillion by March 31, 2031. 25% of the VCP award is tied to each interim milestone, with the remaining 50% tied to the final milestone. If an interim milestone is not achieved within the specified timeframe, the associated portion will roll forward and remain eligible for vesting upon achievement of a subsequent milestone. Achievement of the milestones will be determined based on the rolling average closing price over any 60-day period prior to the relevant milestone date. If a milestone is achieved, vesting of the associated RSUs will occur on April 1, two years following the relevant milestone date, subject to continued employment. --- Signature --- /s/ /s/ George Kanelos, as Attorney-in-Fact for Rene A. Haas (2026-09-10)