David Philip Henry - 17 Feb 2026 Form 4 Insider Report for MKS INC (MKSI)

Role
EVP, Global Str Mktg & GM, MSD
Signature
/s/ M. Kathryn Rickards, attorney-in-fact
Issuer symbol
MKSI
Transactions as of
17 Feb 2026
Net transactions value
-$1,068,322
Form type
4
Filing time
18 Feb 2026, 17:05:02 UTC
Previous filing
09 Feb 2026
Next filing
23 Feb 2026
SEC
View on sec.gov

Reporting Owners (1)

Name Relationship Address Signature Signature date CIK
Henry David Philip EVP, Global Str Mktg & GM, MSD C/O MKS INC., 2 TECH DRIVE, ANDOVER /s/ M. Kathryn Rickards, attorney-in-fact 18 Feb 2026 0001842459

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction MKSI Common Stock Options Exercise +2,406 +15% 18,062 17 Feb 2026 Direct F1
transaction MKSI Common Stock Options Exercise +1,247 +6.9% 19,310 17 Feb 2026 Direct F1
transaction MKSI Common Stock Options Exercise +456 +2.4% 19,766 17 Feb 2026 Direct F1
transaction MKSI Common Stock Options Exercise +1,278 +6.5% 21,044 17 Feb 2026 Direct F1
transaction MKSI Common Stock Options Exercise +1,841 +8.7% 22,885 17 Feb 2026 Direct F1
transaction MKSI Common Stock Options Exercise +2,054 +9% 24,939 17 Feb 2026 Direct F1
transaction MKSI Common Stock Tax liability $1,068,322 -4,097 -16% $260.74 20,841 17 Feb 2026 Direct F2

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Underlying Class Amount Exercise Price Ownership Footnotes
transaction MKSI Restricted Stock Unit Award +2,567 +14% 21,375 17 Feb 2026 Common Stock 2,567 Direct F1, F3
transaction MKSI Restricted Stock Unit Options Exercise -2,406 -11% 18,970 17 Feb 2026 Common Stock 2,406 Direct F1, F4
transaction MKSI Restricted Stock Unit Options Exercise -1,247 -6.6% 17,723 17 Feb 2026 Common Stock 1,247 Direct F1, F5
transaction MKSI Restricted Stock Unit Options Exercise -456 -2.6% 17,266 17 Feb 2026 Common Stock 456 Direct F1, F6
transaction MKSI Restricted Stock Unit Options Exercise -1,278 -7.4% 15,988 17 Feb 2026 Common Stock 1,278 Direct F1, F7
transaction MKSI Restricted Stock Unit Options Exercise -1,841 -12% 14,147 17 Feb 2026 Common Stock 1,841 Direct F1, F8
transaction MKSI Restricted Stock Unit Options Exercise -2,054 -15% 12,093 17 Feb 2026 Common Stock 2,054 Direct F1, F9
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.
F2 These shares were withheld by MKS Inc. to satisfy the tax withholding obligations triggered by the vesting of RSUs and do not represent a discretionary trade by the reporting person.
F3 These RSUs vest in three equal annual installments commencing on February 15, 2027, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.
F4 These RSUs were subject to performance criteria, the achievement of which was determined on February 5, 2024, and thereafter vest in three equal annual installments beginning on February 15, 2024, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.
F5 These RSUs vest in three equal annual installments commencing on February 15, 2024, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.
F6 These RSUs were subject to performance criteria, the achievement of which was determined on February 10, 2025, and thereafter vest in three equal annual installments beginning on February 15, 2025, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.
F7 These RSUs vest in three equal annual installments commencing on February 15, 2025, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.
F8 These RSUs were subject to performance criteria, the achievement of which was determined on February 8, 2026, and thereafter vest in three equal annual installments beginning on February 15, 2026, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.
F9 These RSUs vest in three equal annual installments commencing on February 15, 2026, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.