InsiderTrades

Form 4 for MKSI MKS INC

Accepted 2026-02-23 00:00:00 ET · period of report 2026-02-20 · accession 0001049502-26-000030 · 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
M 2026-02-23 2026-02-20 MKSI Lee John Tseng-Chung Pres, CEO, Dir S - Sale $256.77 -30.0K 171.4K -15% -$7.70M

Purchase Sale Sale after option exercise All abbreviations

Every reported transaction

#TableSecurityDateCodeA/DSharesPriceOwned afterOwnExercise / expiryUnderlyingFootnotes
1 Common Common Stock 2026-02-20 S D 1,988 $257.81 156,586.11 D — — (F3) This transaction was executed in multiple trades at prices ranging from $257.445 to $258.320. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide, upon request, the full information regarding the number of shares and prices at which the transaction was effected.
2 Common Common Stock 2026-02-20 S D 1,890 $259.70 154,696.11 D — — (F4) This transaction was executed in multiple trades at prices ranging from $259.170 to $259.920. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide, upon request, the full information regarding the number of shares and prices at which the transaction was effected.
3 Common Common Stock 2026-02-20 S D 12,812 $256.93 158,574.11 D — — (F2) This transaction was executed in multiple trades at prices ranging from $256.4275 to $257.275. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide, upon request, the full information regarding the number of shares and prices at which the transaction was effected.
4 Common Common Stock 2026-02-20 S D 13,310 $256.05 171,386.11 D — — (F1) This transaction was executed in multiple trades at prices ranging from $255.425 to $256.415. The price reported above reflects the weighted average sale price. The reporting person hereby undertakes to provide, upon request, the full information regarding the number of shares and prices at which the transaction was effected.