STX's three largest insider shareholders as of March 23, 2026 are Holdings, L.P. Valueact (Director, 13.44Mn shares), William D Mosley (Ceo, 398.51K shares), Stephen J Luczo (Director, 225.94K shares).
| Holder | Position | Shares (Direct) | Shares (Indirect) | Report Date |
|---|---|---|---|---|
| Holdings, L.P. Valueact | 0 | 13,437,070 | 22 Feb, 2022 | |
| William D Mosley | Ceo | 375,591 | 0 | 23 Mar, 2026 |
| Gianluca Romano | Evp Cfo | 65,335 | 0 | 12 Mar, 2026 |
| Edward J Zander | 0 | 41,357 | 22 Oct, 2021 | |
| John Christopher Morris | Evp Cto | 17,580 | 0 | 16 Mar, 2026 |
| Stephanie Tilenius | 12,244 | 0 | 05 Nov, 2025 | |
| Ban Seng Teh | Evp Chief Commercial Officer | 11,248 | 0 | 12 Mar, 2026 |
| Kian Fatt Chong | Evp Global Operations | 1,259 | 0 | 12 Mar, 2026 |
| Thomas A Szlosek | 357 | 0 | 12 Nov, 2025 |
* Please note that the shares above only reflect shares from the fund portfolio and the institutional portfolio. Shares from the personal portfolio are excluded from this Institutional Ownership Page. See these insiders' latest transactions here on Insider Page.
| Transaction Date | Insider Name | Security Class | Transaction Type | Shares Traded | Price | Shares Remaining | Ownership | Code |
|---|---|---|---|---|---|---|---|---|
| 19 Mar, 2026 | William D Mosley | Ordinary Shares | D | 24,584 | $406.77 | 375,591 | D | S |
| 13 Mar, 2026 | John Christopher Morris | Ordinary Shares | D | 112 | $377.44 | 17,580 | D | S |
| 11 Mar, 2026 | Kian Fatt Chong | Ordinary Shares | A | 678 | $0.00 | 1,259 | D | M |
| 11 Mar, 2026 | John Christopher Morris | Ordinary Shares | A | 942 | $0.00 | 18,122 | D | M |
| 11 Mar, 2026 | William D Mosley | Ordinary Shares | A | 3,319 | $0.00 | 401,833 | D | M |
| 11 Mar, 2026 | Gianluca Romano | Ordinary Shares | A | 1,695 | $0.00 | 66,182 | D | M |
| 11 Mar, 2026 | Ban Seng Teh | Ordinary Shares | A | 989 | $0.00 | 11,248 | D | M |
| 11 Mar, 2026 | John Christopher Morris | Ordinary Shares | D | 430 | $385.97 | 17,692 | D | F |
| 11 Mar, 2026 | Gianluca Romano | Ordinary Shares | D | 847 | $385.97 | 65,335 | D | F |
| 11 Mar, 2026 | Kian Fatt Chong | Restricted Share Unit | D | 678 | $0.00 | 4,070 | D | M |
| 11 Mar, 2026 | William D Mosley | Ordinary Shares | D | 1,658 | $385.97 | 400,175 | D | F |
| 11 Mar, 2026 | Ban Seng Teh | Restricted Share Unit | D | 989 | $0.00 | 5,934 | D | M |
| 11 Mar, 2026 | William D Mosley | Restricted Share Unit | D | 3,319 | $0.00 | 19,914 | D | M |
| 11 Mar, 2026 | Gianluca Romano | Restricted Share Unit | D | 1,695 | $0.00 | 10,170 | D | M |
| 11 Mar, 2026 | John Christopher Morris | Restricted Share Unit | D | 942 | $0.00 | 5,652 | D | M |
| 09 Mar, 2026 | Ban Seng Teh | Ordinary Shares | A | 599 | $0.00 | 9,596 | D | M |
| 09 Mar, 2026 | Kian Fatt Chong | Ordinary Shares | A | 202 | $0.00 | 202 | D | M |
| 09 Mar, 2026 | William D Mosley | Ordinary Shares | A | 2,815 | $0.00 | 398,712 | D | M |
| 09 Mar, 2026 | Gianluca Romano | Ordinary Shares | A | 958 | $0.00 | 64,208 | D | M |
| 09 Mar, 2026 | John Christopher Morris | Ordinary Shares | A | 499 | $0.00 | 17,065 | D | M |