InsiderTrades

Form 4 for MKSI MKS INC

Accepted 2026-05-26 14:15:39 ET · period of report 2026-05-22 · accession 0001049502-26-000088 · SEC index · Original document

Summary rows

Aggregated the way they appear in lists: one row per insider, transaction code and security table.

X Filed Traded Ticker Insider Title Type Price Qty Owned ΔOwn Value
T 2026-05-26 14:15 2026-05-22 MKSI Lee John Tseng-Chung Pres, CEO, Dir S - Sale $315.48 -10.0K 144.7K -6% -$3.15M

Purchase Sale Sale after option exercise All abbreviations

Every reported transaction

#TableSecurityDateCodeA/DSharesPriceOwned afterOwnExercise / expiryUnderlyingFootnotes
1 Common Common Stock 2026-05-22 S D 10,000 $315.48 144,696.11 D — — (F1) This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 20, 2026.