John Tseng-Chung Lee - 20 Feb 2026 Form 4 Insider Report for MKS INC (MKSI)

Role
President & CEO, Director
Signature
/s/ M. Kathryn Rickards, attorney-in-fact
Issuer symbol
MKSI
Transactions as of
20 Feb 2026
Net transactions value
-$7,703,242
Form type
4
Filing time
23 Feb 2026, 14:25:50 UTC
Previous filing
19 Feb 2026
Next filing
24 Feb 2026
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Lee John Tseng-Chung President & CEO, Director C/O MKS INC., 2 TECH DRIVE, ANDOVER /s/ M. Kathryn Rickards, attorney-in-fact 23 Feb 2026 0001414656

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction MKSI Common Stock Sale $3,408,076 -13,310 -7.2% $256.05 171,386 20 Feb 2026 Direct F1
transaction MKSI Common Stock Sale $3,291,804 -12,812 -7.5% $256.93 158,574 20 Feb 2026 Direct F2
transaction MKSI Common Stock Sale $512,523 -1,988 -1.3% $257.81 156,586 20 Feb 2026 Direct F3
transaction MKSI Common Stock Sale $490,839 -1,890 -1.2% $259.70 154,696 20 Feb 2026 Direct F4
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
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.
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.
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.
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.