MKSI · MKS Inc. Common Stock
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| Carlyle Partners VI Cayman Holdings, L.P. 10% Owner | ▼ Sell | Open Market | 6,482,732 Shares held | 5/8/2023 | View profile |
| John Tseng-Chung Lee President & CEO | ▼ Sell | Open Market | 134,776 Shares held | 8/14/2026 | View profile |
| Kathleen Flaherty Burke Sr. VP, GC & Secretary | ▼ Sell | Open Market | 49,439 Shares held | 5/11/2026 | View profile |
| Gerald G. Colella Director | ▼ Sell | Open Market | 20,017 Shares held | 5/27/2026 | View profile |
| James Alan Schreiner Sr. VP & COO | ▼ Sell | Open Market | 19,201 Shares held | 6/12/2026 | View profile |
| Elizabeth Mora Director | ▼ Sell | Open Market | 19,145 Shares held | 6/1/2026 | View profile |
| Raj Batra Director | ▲ Buy | Grant | 16,227 Shares held | 5/11/2026 | View profile |
| Gitin Mark Milton SVP & GM, L&M Division | ▼ Sell | Tax Withholding | 16,134 Shares held | 2/15/2024 | View profile |
| Eric Robert Taranto SVP & GM, V&A Division | ▼ Sell | Open Market | 12,596 Shares held | 5/11/2026 | View profile |
| Warner Michelle M Director | ▲ Buy | Grant | 10,852 Shares held | 5/7/2024 | View profile |
| David Philip Henry SVP, Corp Mkt, PMO & Glob Svc | ▼ Sell | Open Market | 10,422 Shares held | 6/1/2026 | View profile |
| Joseph B. Donahue Director | ▼ Sell | Open Market | 10,033 Shares held | 5/27/2026 | View profile |
| Jacqueline F. Moloney Director | ▼ Sell | Open Market | 8,775 Shares held | 5/14/2026 | View profile |
| Peter Cannone III Director | ▼ Sell | Open Market | 7,794 Shares held | 5/18/2026 | View profile |
| Wissam G. Jabre EVP, CFO | ▲ Buy | Grant | 5,270 Shares held | 5/11/2026 | View profile |
| John Edward Williams EVP & GM, PSD | ▼ Sell | Open Market | 4,098 Shares held | 8/3/2026 | View profile |
| WILD GEOFFREY Director | ▲ Buy | Grant | 1,813 Shares held | 8/17/2022 | View profile |
| Michelle M. McCarthy VP, CAO | ▼ Sell | Open Market | 2 Shares held | 6/5/2026 | View profile |
| Ramakumar Mayampurath EVP & CFO | ▼ Sell | Open Market | 1 Shares held | 5/22/2026 | View profile |
| BAGSHAW SETH H Sr. VP, CFO & Treasurer | ▼ Sell | Open Market | 1 Shares held | 2/22/2024 | View profile |
Transaction History
| John Tseng-Chung Lee | ▼ Sell | Open Market | 10,000 | $3.0M | 8/14/2026 |
| John Edward Williams | ▼ Sell | Open Market | 457 | $132K | 8/3/2026 |
| James Alan Schreiner | ▼ Sell | Open Market | 2,471 | $854K | 6/12/2026 |
| James Alan Schreiner | ▼ Sell | Open Market | 812 | $281K | 6/12/2026 |
| James Alan Schreiner | ▼ Sell | Open Market | 217 | $75K | 6/12/2026 |
| James Alan Schreiner | ▼ Sell | Open Market | 781 | $248K | 6/10/2026 |
| Michelle M. McCarthy | ▼ Sell | Open Market | 2,434 | $767K | 6/5/2026 |
| David Philip Henry | ▼ Sell | Open Market | 6,000 | $1.9M | 6/1/2026 |
| Elizabeth Mora | ▼ Sell | Open Market | 300 | $95K | 6/1/2026 |
| Joseph B. Donahue | ▼ Sell | Open Market | 2,100 | $689K | 5/27/2026 |
| Gerald G. Colella | ▼ Sell | Open Market | 464 | $153K | 5/27/2026 |
| Gerald G. Colella | ▼ Sell | Open Market | 8,210 | $2.7M | 5/27/2026 |
| Gerald G. Colella | ▼ Sell | Open Market | 4,876 | $1.6M | 5/27/2026 |
| Gerald G. Colella | ▼ Sell | Open Market | 1,811 | $608K | 5/27/2026 |
| Gerald G. Colella | ▼ Sell | Open Market | 1,626 | $547K | 5/27/2026 |
| Gerald G. Colella | ▼ Sell | Open Market | 213 | $72K | 5/27/2026 |
| Gerald G. Colella | ▼ Sell | Open Market | 2,800 | $948K | 5/27/2026 |
| David Philip Henry | ▼ Sell | Open Market | 2,500 | $826K | 5/26/2026 |
| Ramakumar Mayampurath | ▼ Sell | Open Market | 8,810 | $2.8M | 5/22/2026 |
| John Tseng-Chung Lee | ▼ Sell | Open Market | 10,000 | $3.2M | 5/22/2026 |
| Peter Cannone III | ▼ Sell | Open Market | 1,350 | $410K | 5/18/2026 |
| Jacqueline F. Moloney | ▼ Sell | Open Market | 1,000 | $312K | 5/14/2026 |
| Jacqueline F. Moloney | ▼ Sell | Open Market | 1,400 | $447K | 5/13/2026 |
| Eric Robert Taranto | ▼ Sell | Open Market | 2,849 | $911K | 5/11/2026 |
| Jacqueline F. Moloney | ▲ Buy | Grant | 782 | — | 5/11/2026 |
| Wissam G. Jabre | ▲ Buy | Grant | 782 | — | 5/11/2026 |
| Elizabeth Mora | ▲ Buy | Grant | 782 | — | 5/11/2026 |
| Kathleen Flaherty Burke | ▼ Sell | Open Market | 4,355 | $1.4M | 5/11/2026 |
| Joseph B. Donahue | ▲ Buy | Grant | 782 | — | 5/11/2026 |
| Peter Cannone III | ▲ Buy | Grant | 782 | — | 5/11/2026 |
| Raj Batra | ▲ Buy | Grant | 782 | — | 5/11/2026 |
| Gerald G. Colella | ▲ Buy | Grant | 782 | — | 5/11/2026 |
| John Edward Williams | ▲ Buy | Option Exercise | 1,741 | — | 4/17/2026 |
| John Edward Williams | ▼ Sell | Tax Withholding | 826 | $223K | 4/17/2026 |
| Michelle M. McCarthy | ▲ Buy | Option Exercise | 968 | — | 4/15/2026 |
| Michelle M. McCarthy | ▲ Buy | Option Exercise | 1,107 | — | 4/15/2026 |
| Michelle M. McCarthy | ▲ Buy | Option Exercise | 1,736 | — | 4/15/2026 |
| Michelle M. McCarthy | ▼ Sell | Tax Withholding | 1,375 | $377K | 4/15/2026 |
| Jacqueline F. Moloney | ▼ Sell | Open Market | 340 | $73K | 3/12/2026 |
| Eric Robert Taranto | ▼ Sell | Open Market | 4,568 | $1.0M | 3/6/2026 |
| Elizabeth Mora | ▼ Sell | Open Market | 300 | $72K | 3/2/2026 |
| James Alan Schreiner | ▼ Sell | Open Market | 4,100 | $1.0M | 2/24/2026 |
| Gerald G. Colella | ▼ Sell | Open Market | 10,000 | $2.5M | 2/24/2026 |
| Gerald G. Colella | ▼ Sell | Open Market | 10,000 | $2.5M | 2/20/2026 |
| Peter Cannone III | ▼ Sell | Open Market | 1,250 | $323K | 2/20/2026 |
| Eric Robert Taranto | ▼ Sell | Open Market | 1,453 | $360K | 2/20/2026 |
| David Philip Henry | ▼ Sell | Open Market | 2,000 | $523K | 2/20/2026 |
| Michelle M. McCarthy | ▼ Sell | Open Market | 650 | $162K | 2/20/2026 |
| Michelle M. McCarthy | ▼ Sell | Open Market | 816 | $204K | 2/20/2026 |
| Jacqueline F. Moloney | ▼ Sell | Open Market | 829 | $205K | 2/20/2026 |
| John Edward Williams | ▼ Sell | Open Market | 2,043 | $524K | 2/20/2026 |
| Kathleen Flaherty Burke | ▼ Sell | Open Market | 4,254 | $1.1M | 2/20/2026 |
| John Tseng-Chung Lee | ▼ Sell | Open Market | 13,310 | $3.4M | 2/20/2026 |
| John Tseng-Chung Lee | ▼ Sell | Open Market | 12,812 | $3.3M | 2/20/2026 |
| John Tseng-Chung Lee | ▼ Sell | Open Market | 1,988 | $513K | 2/20/2026 |
| John Tseng-Chung Lee | ▼ Sell | Open Market | 1,890 | $491K | 2/20/2026 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 1,764 | — | 2/17/2026 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 914 | — | 2/17/2026 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 348 | — | 2/17/2026 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 976 | — | 2/17/2026 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 1,167 | — | 2/17/2026 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 1,303 | — | 2/17/2026 |
| Eric Robert Taranto | ▼ Sell | Tax Withholding | 2,712 | $707K | 2/17/2026 |
| David Philip Henry | ▲ Buy | Option Exercise | 2,406 | — | 2/17/2026 |
| David Philip Henry | ▲ Buy | Option Exercise | 1,247 | — | 2/17/2026 |
| David Philip Henry | ▲ Buy | Option Exercise | 456 | — | 2/17/2026 |
| David Philip Henry | ▲ Buy | Option Exercise | 1,278 | — | 2/17/2026 |
| David Philip Henry | ▲ Buy | Option Exercise | 1,841 | — | 2/17/2026 |
| David Philip Henry | ▲ Buy | Option Exercise | 2,054 | — | 2/17/2026 |
| David Philip Henry | ▼ Sell | Tax Withholding | 4,097 | $1.1M | 2/17/2026 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 2,567 | — | 2/17/2026 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 1,330 | — | 2/17/2026 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 432 | — | 2/17/2026 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 1,211 | — | 2/17/2026 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 1,741 | — | 2/17/2026 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 1,944 | — | 2/17/2026 |
| James Alan Schreiner | ▼ Sell | Tax Withholding | 4,344 | $1.1M | 2/17/2026 |
| John Edward Williams | ▲ Buy | Option Exercise | 300 | — | 2/17/2026 |
| John Edward Williams | ▲ Buy | Option Exercise | 841 | — | 2/17/2026 |
| John Edward Williams | ▲ Buy | Option Exercise | 991 | — | 2/17/2026 |
| John Edward Williams | ▲ Buy | Option Exercise | 1,106 | — | 2/17/2026 |
| John Edward Williams | ▼ Sell | Tax Withholding | 1,195 | $312K | 2/17/2026 |
| Ramakumar Mayampurath | ▲ Buy | Option Exercise | 2,958 | — | 2/17/2026 |
| Ramakumar Mayampurath | ▲ Buy | Option Exercise | 2,702 | — | 2/17/2026 |
| Ramakumar Mayampurath | ▼ Sell | Tax Withholding | 2,516 | $656K | 2/17/2026 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 3,451 | — | 2/17/2026 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 1,788 | — | 2/17/2026 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 563 | — | 2/17/2026 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 1,576 | — | 2/17/2026 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 2,336 | — | 2/17/2026 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 2,493 | — | 2/17/2026 |
| Kathleen Flaherty Burke | ▼ Sell | Tax Withholding | 5,318 | $1.4M | 2/17/2026 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 22,088 | — | 2/17/2026 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 7,654 | — | 2/17/2026 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 3,859 | — | 2/17/2026 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 16,989 | — | 2/17/2026 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 12,091 | — | 2/17/2026 |
| John Tseng-Chung Lee | ▼ Sell | Tax Withholding | 32,548 | $8.5M | 2/17/2026 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 7,208 | — | 2/17/2026 |
| Elizabeth Mora | ▼ Sell | Open Market | 300 | $48K | 12/2/2025 |
| Ramakumar Mayampurath | ▲ Buy | Option Exercise | 8,295 | — | 11/17/2025 |
| Ramakumar Mayampurath | ▼ Sell | Tax Withholding | 2,628 | $375K | 11/17/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 158 | — | 10/31/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 52 | — | 10/31/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 82 | — | 10/31/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 144 | — | 10/31/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 341 | — | 10/31/2025 |
| Kathleen Flaherty Burke | ▼ Sell | Tax Withholding | 777 | $112K | 10/31/2025 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 352 | — | 10/31/2025 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 1,651 | — | 10/31/2025 |
| John Tseng-Chung Lee | ▼ Sell | Tax Withholding | 2,003 | $288K | 10/31/2025 |
| James Alan Schreiner | ▼ Sell | Open Market | 711 | $99K | 10/22/2025 |
| Jacqueline F. Moloney | ▼ Sell | Open Market | 300 | $37K | 10/1/2025 |
| James Alan Schreiner | ▼ Sell | Open Market | 838 | $104K | 9/18/2025 |
| David Philip Henry | ▼ Sell | Open Market | 5,000 | $650K | 9/18/2025 |
| Elizabeth Mora | ▼ Sell | Open Market | 300 | $30K | 9/2/2025 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 2,641 | — | 8/18/2025 |
| James Alan Schreiner | ▼ Sell | Tax Withholding | 1,249 | $125K | 8/18/2025 |
| John Edward Williams | ▲ Buy | Option Exercise | 947 | — | 8/15/2025 |
| John Edward Williams | ▼ Sell | Tax Withholding | 308 | $32K | 8/15/2025 |
| Jacqueline F. Moloney | ▼ Sell | Open Market | 300 | $28K | 8/1/2025 |
| James Alan Schreiner | ▼ Sell | Open Market | 957 | $98K | 7/7/2025 |
| David Philip Henry | ▼ Sell | Open Market | 2,000 | $210K | 7/3/2025 |
| Elizabeth Mora | ▼ Sell | Open Market | 300 | $25K | 6/2/2025 |
| Elizabeth Mora | ▲ Buy | Grant | 2,479 | — | 5/12/2025 |
| Jacqueline F. Moloney | ▲ Buy | Grant | 2,479 | — | 5/12/2025 |
| Wissam G. Jabre | ▲ Buy | Grant | 2,479 | — | 5/12/2025 |
| Joseph B. Donahue | ▲ Buy | Grant | 2,479 | — | 5/12/2025 |
| Peter Cannone III | ▲ Buy | Grant | 2,479 | — | 5/12/2025 |
| Raj Batra | ▲ Buy | Grant | 2,479 | — | 5/12/2025 |
| Gerald G. Colella | ▲ Buy | Grant | 2,479 | — | 5/12/2025 |
| John Edward Williams | ▲ Buy | Option Exercise | 1,740 | — | 4/17/2025 |
| John Edward Williams | ▼ Sell | Tax Withholding | 565 | $36K | 4/17/2025 |
| Michelle M. McCarthy | ▲ Buy | Option Exercise | 968 | — | 4/15/2025 |
| Michelle M. McCarthy | ▲ Buy | Option Exercise | 1,106 | — | 4/15/2025 |
| Michelle M. McCarthy | ▼ Sell | Tax Withholding | 608 | $42K | 4/15/2025 |
| Elizabeth Mora | ▼ Sell | Open Market | 275 | $25K | 3/3/2025 |
| Jacqueline F. Moloney | ▼ Sell | Open Market | 300 | $28K | 3/3/2025 |
| John Edward Williams | ▲ Buy | Option Exercise | 915 | — | 2/18/2025 |
| John Edward Williams | ▲ Buy | Option Exercise | 658 | — | 2/18/2025 |
| John Edward Williams | ▲ Buy | Option Exercise | 300 | — | 2/18/2025 |
| John Edward Williams | ▲ Buy | Option Exercise | 841 | — | 2/18/2025 |
| John Edward Williams | ▼ Sell | Tax Withholding | 901 | $93K | 2/18/2025 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 1,119 | — | 2/18/2025 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 805 | — | 2/18/2025 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 1,764 | — | 2/18/2025 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 914 | — | 2/18/2025 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 348 | — | 2/18/2025 |
| Eric Robert Taranto | ▲ Buy | Option Exercise | 975 | — | 2/18/2025 |
| Eric Robert Taranto | ▼ Sell | Tax Withholding | 1,760 | $182K | 2/18/2025 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 1,630 | — | 2/18/2025 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 1,173 | — | 2/18/2025 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 2,566 | — | 2/18/2025 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 1,329 | — | 2/18/2025 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 432 | — | 2/18/2025 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 1,211 | — | 2/18/2025 |
| James Alan Schreiner | ▼ Sell | Tax Withholding | 3,648 | $378K | 2/18/2025 |
| David Philip Henry | ▲ Buy | Option Exercise | 1,528 | — | 2/18/2025 |
| David Philip Henry | ▲ Buy | Option Exercise | 1,099 | — | 2/18/2025 |
| David Philip Henry | ▲ Buy | Option Exercise | 2,406 | — | 2/18/2025 |
| David Philip Henry | ▲ Buy | Option Exercise | 1,246 | — | 2/18/2025 |
| David Philip Henry | ▲ Buy | Option Exercise | 456 | — | 2/18/2025 |
| David Philip Henry | ▲ Buy | Option Exercise | 1,278 | — | 2/18/2025 |
| David Philip Henry | ▼ Sell | Tax Withholding | 2,372 | $246K | 2/18/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 2,287 | — | 2/18/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 1,645 | — | 2/18/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 3,608 | — | 2/18/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 1,870 | — | 2/18/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 588 | — | 2/18/2025 |
| Kathleen Flaherty Burke | ▲ Buy | Option Exercise | 1,648 | — | 2/18/2025 |
| Kathleen Flaherty Burke | ▼ Sell | Tax Withholding | 3,970 | $412K | 2/18/2025 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 14,041 | — | 2/18/2025 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 6,735 | — | 2/18/2025 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 22,088 | — | 2/18/2025 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 7,654 | — | 2/18/2025 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 4,035 | — | 2/18/2025 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 7,207 | — | 2/18/2025 |
| John Tseng-Chung Lee | ▼ Sell | Tax Withholding | 27,332 | $2.8M | 2/18/2025 |
| Gerald G. Colella | ▼ Sell | Open Market | 8,000 | $836K | 2/18/2025 |
| Jacqueline F. Moloney | ▼ Sell | Open Market | 300 | $34K | 12/10/2024 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 2,010 | — | 12/6/2024 |
| John Tseng-Chung Lee | ▲ Buy | Option Exercise | 984 | — | 12/6/2024 |
| John Tseng-Chung Lee | ▼ Sell | Tax Withholding | 2,994 | $343K | 12/6/2024 |
| Elizabeth Mora | ▼ Sell | Open Market | 275 | $31K | 12/2/2024 |
| Wissam G. Jabre | ▲ Buy | Grant | 2,009 | — | 11/4/2024 |
| Jacqueline F. Moloney | ▼ Sell | Open Market | 250 | $27K | 10/1/2024 |
| Elizabeth Mora | ▼ Sell | Open Market | 275 | $32K | 9/3/2024 |
| James Alan Schreiner | ▲ Buy | Option Exercise | 3,961 | — | 8/19/2024 |
| James Alan Schreiner | ▼ Sell | Tax Withholding | 1,873 | $223K | 8/19/2024 |
| John Edward Williams | ▼ Sell | Open Market | 1,800 | $214K | 8/16/2024 |
| John Edward Williams | ▲ Buy | Option Exercise | 946 | — | 8/15/2024 |
| John Edward Williams | ▼ Sell | Tax Withholding | 307 | $35K | 8/15/2024 |
| Jacqueline F. Moloney | ▼ Sell | Open Market | 250 | $31K | 8/1/2024 |
| Elizabeth Mora | ▼ Sell | Open Market | 275 | $36K | 6/3/2024 |
| Raj Batra | ▲ Buy | Grant | 1,622 | — | 5/7/2024 |
| Warner Michelle M | ▲ Buy | Grant | 1,622 | — | 5/7/2024 |
| Jacqueline F. Moloney | ▲ Buy | Grant | 1,622 | — | 5/7/2024 |
| Elizabeth Mora | ▲ Buy | Grant | 1,622 | — | 5/7/2024 |
| Joseph B. Donahue | ▲ Buy | Grant | 1,622 | — | 5/7/2024 |
| Peter Cannone III | ▲ Buy | Grant | 1,622 | — | 5/7/2024 |