MKSI

SEC source: 0001049502-26-000045 · form4.xml · nonDerivative · entry 1

CANNONE PETER III · CIK 0001276985 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,362.08

F1 · price: This transaction was executed in multiple trades at prices ranging from $258.040 to $258.285. 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.

SEC source: 0001049502-26-000042 · form4.xml · nonDerivative · entry 1

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,012.6404

SEC source: 0001049502-26-000040 · form4.xml · nonDerivative · entry 1

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 18,841.368

SEC source: 0001049502-26-000038 · form4.xml · nonDerivative · entry 2

McCarthy Michelle M · CIK 0001732461 · VP & Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0

F2 · price: This transaction was executed in multiple trades at prices ranging from $250.160 to $250.790. 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.

SEC source: 0001049502-26-000038 · form4.xml · nonDerivative · entry 1

McCarthy Michelle M · CIK 0001732461 · VP & Chief Accounting Officer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 816

F1 · price: This transaction was executed in multiple trades at prices ranging from $249.070 to $250.030. 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.

SEC source: 0001049502-26-000036 · form4.xml · nonDerivative · entry 1

Moloney Jacqueline F · CIK 0001501968 · Director

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,733.304

SEC source: 0001049502-26-000034 · form4.xml · nonDerivative · entry 1

Williams John Edward · CIK 0001710173 · EVP & GM, PSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 3,640.099

F1 · price: This transaction was executed in multiple trades at prices ranging from $256.3902 to $257.150. 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.

SEC source: 0001049502-26-000032 · form4.xml · nonDerivative · entry 1

Burke Kathleen Flaherty · CIK 0001775435 · EVP, GC & Secretary

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 53,794.485

SEC source: 0001049502-26-000030 · form4.xml · nonDerivative · entry 4

Lee John Tseng-Chung · CIK 0001414656 · Director · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 154,696.1077

F4 · price: 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.

SEC source: 0001049502-26-000030 · form4.xml · nonDerivative · entry 3

Lee John Tseng-Chung · CIK 0001414656 · Director · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 156,586.1077

F3 · price: 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.

SEC source: 0001049502-26-000030 · form4.xml · nonDerivative · entry 2

Lee John Tseng-Chung · CIK 0001414656 · Director · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 158,574.1077

F2 · price: 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.

SEC source: 0001049502-26-000030 · form4.xml · nonDerivative · entry 1

Lee John Tseng-Chung · CIK 0001414656 · Director · President & CEO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 171,386.1077

F1 · price: 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.

SEC source: 0001049502-26-000049 · form4.xml · nonDerivative · entry 1

COLELLA GERALD G · CIK 0001256715 · Director

10b5-1 filing: No plan indicated

Ownership: Indirect · By The Gerald G. Colella 2019 Trust

Disclosed balance after: 50,017

F1 · price: This transaction was executed in multiple trades at prices ranging from $252.60 to $253.86. 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.

SEC source: 0001049502-26-000028 · form4.xml · derivative · entry 14

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 8,028.666

Underlying: Common Stock · 1,303 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F9 · derivative.exercise_date: 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.

F9 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000028 · form4.xml · derivative · entry 13

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 9,331.666

Underlying: Common Stock · 1,167.36 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F8 · derivative.exercise_date: 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.

F8 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000028 · form4.xml · derivative · entry 12

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 10,499.026

Underlying: Common Stock · 976 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F7 · derivative.exercise_date: 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.

F7 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000028 · form4.xml · derivative · entry 11

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,475.026

Underlying: Common Stock · 348.33 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F6 · derivative.exercise_date: 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.

F6 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000028 · form4.xml · derivative · entry 10

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,823.356

Underlying: Common Stock · 914.048 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F5 · derivative.exercise_date: 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.

F5 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000028 · form4.xml · derivative · entry 9

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,737.404

Underlying: Common Stock · 1,764.153 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F4 · derivative.exercise_date: 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.

F4 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000028 · form4.xml · derivative · entry 8

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 14,501.557

Underlying: Common Stock · 1,758.956 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F3 · derivative.exercise_date: 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.

F3 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000028 · form4.xml · nonDerivative · entry 7

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 21,465.3704

F2 · kind: 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.

SEC source: 0001049502-26-000028 · form4.xml · nonDerivative · entry 6

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 24,177.1384

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000028 · form4.xml · nonDerivative · entry 5

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,874.1384

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000028 · form4.xml · nonDerivative · entry 4

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 21,706.7784

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000028 · form4.xml · nonDerivative · entry 3

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,730.7784

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000028 · form4.xml · nonDerivative · entry 2

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,382.4484

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000028 · form4.xml · nonDerivative · entry 1

Taranto Eric Robert · CIK 0001842235 · EVP & GM, VSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 19,468.4004

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000026 · form4.xml · derivative · entry 14

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,093.416

Underlying: Common Stock · 2,054 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F9 · derivative.exercise_date: 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.

F9 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000026 · form4.xml · derivative · entry 13

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 14,147.416

Underlying: Common Stock · 1,840.64 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F8 · derivative.exercise_date: 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.

F8 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000026 · form4.xml · derivative · entry 12

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 15,988.056

Underlying: Common Stock · 1,278 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F7 · derivative.exercise_date: 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.

F7 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000026 · form4.xml · derivative · entry 11

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17,266.056

Underlying: Common Stock · 456.45 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F6 · derivative.exercise_date: 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.

F6 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000026 · form4.xml · derivative · entry 10

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 17,722.506

Underlying: Common Stock · 1,247.156 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F5 · derivative.exercise_date: 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.

F5 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000026 · form4.xml · derivative · entry 9

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 18,969.662

Underlying: Common Stock · 2,405.571 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F4 · derivative.exercise_date: 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.

F4 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000026 · form4.xml · derivative · entry 8

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 21,375.233

Underlying: Common Stock · 2,567.126 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F3 · derivative.exercise_date: 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.

F3 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000026 · form4.xml · nonDerivative · entry 7

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,841.368

F2 · kind: 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.

SEC source: 0001049502-26-000026 · form4.xml · nonDerivative · entry 6

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 24,938.637

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000026 · form4.xml · nonDerivative · entry 5

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 22,884.637

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000026 · form4.xml · nonDerivative · entry 4

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 21,043.997

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000026 · form4.xml · nonDerivative · entry 3

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 19,765.997

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000026 · form4.xml · nonDerivative · entry 2

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 19,309.547

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000026 · form4.xml · nonDerivative · entry 1

Henry David Philip · CIK 0001842459 · EVP, Global Str Mktg & GM, MSD

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 18,062.391

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

SEC source: 0001049502-26-000024 · form4.xml · derivative · entry 14

Schreiner James Alan · CIK 0001797189 · EVP & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 11,396.475

Underlying: Common Stock · 1,944 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F9 · derivative.exercise_date: 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.

F9 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000024 · form4.xml · derivative · entry 13

Schreiner James Alan · CIK 0001797189 · EVP & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 13,340.475

Underlying: Common Stock · 1,740.8 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F8 · derivative.exercise_date: 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.

F8 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000024 · form4.xml · derivative · entry 12

Schreiner James Alan · CIK 0001797189 · EVP & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 15,081.275

Underlying: Common Stock · 1,211 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F7 · derivative.exercise_date: 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.

F7 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000024 · form4.xml · derivative · entry 11

Schreiner James Alan · CIK 0001797189 · EVP & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,292.275

Underlying: Common Stock · 432.48 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F6 · derivative.exercise_date: 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.

F6 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000024 · form4.xml · derivative · entry 10

Schreiner James Alan · CIK 0001797189 · EVP & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 16,724.755

Underlying: Common Stock · 1,330.434 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F5 · derivative.exercise_date: 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.

F5 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000024 · form4.xml · derivative · entry 9

Schreiner James Alan · CIK 0001797189 · EVP & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 18,055.189

Underlying: Common Stock · 2,566.678 shares

Expires not disclosed

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F4 · derivative.exercise_date: 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.

F4 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000024 · form4.xml · derivative · entry 8

Schreiner James Alan · CIK 0001797189 · EVP & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,621.867

Underlying: Common Stock · 2,376.968 shares

Expires not disclosed

F1 · derivative.exercise_price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.

F3 · derivative.exercise_date: 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.

F3 · derivative.expiration_date: 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.

SEC source: 0001049502-26-000024 · form4.xml · nonDerivative · entry 7

Schreiner James Alan · CIK 0001797189 · EVP & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,501.962

F2 · kind: 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.

SEC source: 0001049502-26-000024 · form4.xml · nonDerivative · entry 6

Schreiner James Alan · CIK 0001797189 · EVP & COO

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 31,845.726

Exercise/conversion can include RSU settlement. Transaction price and option strike are different fields; a missing price is not zero. Derivative and underlying rows can describe the same event.

F1 · price: Each restricted stock unit (RSU) represents the contingent right to receive one share of common stock of MKS Inc.