Grisenthwaite Richard Roy 4
4 · ARM HOLDINGS PLC /UK · Filed May 19, 2026
Research Summary
AI-generated summary of this filing
ARM (ARM) Chief Architect Richard Grisenthwaite Sells Shares
What Happened
- Richard Roy Grisenthwaite, Chief Architect at ARM Holdings plc, had multiple RSU/derivative transactions reported May 15, 2026 and subsequently disposed of shares. Following vesting/conversion/exercise activity, 21,301 ADSs were surrendered to satisfy tax withholding on May 15 (valued at $4,455,317 at $209.16), and an additional 24,339 ADSs were sold in an open-market transaction on May 18, 2026 for $5,090,502 (weighted average price $209.15; sales ranged $209.03–$209.66).
Key Details
- Primary dates: May 15, 2026 (awards, vesting/conversion/exercises; tax withholding), May 18, 2026 (open-market sale). Filing date: May 19, 2026 (reports May 15 transactions).
- Dispositions: 21,301 ADSs withheld for taxes at $209.16 = $4,455,317 (code F); 24,339 ADSs sold publicly at a weighted avg $209.15 = $5,090,502 (code S). Weighted sale price range: $209.03–$209.66.
- Conversion/exercise activity: multiple exercise/conversion entries (code M) on May 15 converting derivative awards to shares/ADSs.
- Award activity: several RSU grants/awards reported (code A) on May 15, including awards with future vesting schedules (see footnotes F11, F12).
- Footnotes: ADSs represent ordinary shares (F1); some RSUs were performance-based and vested following certification (F2, F5, F7); F9 notes ordinary shares were withheld to satisfy tax obligations on RSU vesting; F10 provides sale price breakdown on request.
- Shares owned after the transactions were not specified in the filing.
Context
- The filings show typical post-vesting activity: RSUs/performance awards converted to ADSs (M/A codes), shares were withheld to cover tax obligations (F), and remaining shares were sold in the open market (S). This pattern is generally a cashless exercise/settlement plus routine sale rather than a straightforward purchase. No 10% owner or gift (G) activity is indicated.
Insider Transaction Report
Form 4
Grisenthwaite Richard Roy
Chief Architect
Transactions
- Award
Ordinary Shares
[F1][F2][F3]2026-05-15+5,217→ 5,543 total - Exercise/Conversion
Ordinary Shares
[F1][F4][F3]2026-05-15+2,046→ 7,589 total - Exercise/Conversion
Ordinary Shares
[F1][F4][F3]2026-05-15+14,595→ 22,184 total - Award
Ordinary Shares
[F1][F5][F3]2026-05-15+4,158→ 26,342 total - Exercise/Conversion
Ordinary Shares
[F1][F6][F3]2026-05-15+1,631→ 27,973 total - Award
Ordinary Shares
[F1][F7][F3]2026-05-15+13,315→ 41,288 total - Exercise/Conversion
Ordinary Shares
[F1][F8][F3]2026-05-15+4,352→ 45,640 total - Tax Payment
Ordinary Shares
[F1][F9]2026-05-15$209.16/sh−21,301$4,455,317→ 24,339 total - Sale
Ordinary Shares
[F1][F10]2026-05-18$209.15/sh−24,339$5,090,502→ 0 total - Award
Restricted Stock Units
[F3][F11]2026-05-15+6,648→ 106,282 total→ Ordinary Shares (6,648 underlying) - Award
Restricted Stock Units
[F3][F12]2026-05-15+34,785→ 141,067 total→ Ordinary Shares (34,785 underlying) - Exercise/Conversion
Restricted Stock Units
[F3][F4]2026-05-15−2,046→ 139,021 total→ Ordinary Shares (2,046 underlying) - Exercise/Conversion
Restricted Stock Units
[F3][F4]2026-05-15−14,595→ 124,426 total→ Ordinary Shares (14,595 underlying) - Exercise/Conversion
Restricted Stock Units
[F3][F6]2026-05-15−1,631→ 122,795 total→ Ordinary Shares (1,631 underlying) - Exercise/Conversion
Restricted Stock Units
[F3][F8]2026-05-15−4,352→ 118,443 total→ Ordinary Shares (4,352 underlying)
Footnotes (12)
- [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.
- [F10]Represents weighted average sales price. The shares were sold at prices ranging from $209.03 to $209.66. The reporting person will provide upon request, to the SEC, the Issuer or security holder of the Issuer, full information regarding the number of shares sold at each separate price
- [F11]This RSU award was granted effective May 15, 2026. 30% will vest on each of May 15, 2027, and May 15, 2028, and the remaining 40% will vest on May 15, 2029, subject to continued service to the Company.
- [F12]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.
- [F2]Represents performance-based restricted stock units granted on May 1, 2025, which vested on May 15, 2026, following certification of the satisfaction of certain performance conditions by the Remuneration Committee (the "Remuneration Committee") of the Board of Directors of the Company.
- [F3]Each restricted stock unit ("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 1, 2025. 30% of the award vested on May 15, 2026. 30% of the award will vest on May 15, 2027, and the remaining 40% will vest on May 15, 2028, subject to continued service to the Company.
- [F5]Represents performance-based RSUs granted on May 13, 2024, which vested on May 15, 2026, following certification of the satisfaction of certain performance conditions by the Remuneration Committee.
- [F6]This RSU award was granted on May 13, 2024, 30% of which vested on each of May 15, 2025 and May 15, 2026. The remaining 40% will vest on May 15, 2027, subject to continued service to the Company.
- [F7]Represents performance-based RSUs granted on May 23, 2023, which vested on May 15, 2026, following certification of the satisfaction of certain performance conditions by the Remuneration Committee.
- [F8]This RSU award was granted on May 23, 2023 and vested on May 15, 2026.
- [F9]Ordinary Shares withheld to satisfy tax withholding requirements on vesting of RSUs.
Signature
/s/ George Kanelos, as Attorney-in-Fact for Richard Roy Grisenthwaite|2026-05-19