BAGSHAW SETH H

SEC source: 0001127602-24-006799 · form4.xml · nonDerivative · entry 3

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 0.788

F3 · price: This transaction was executed in multiple trades at prices ranging from $124.450 to $124.640. 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: 0001127602-24-006799 · form4.xml · nonDerivative · entry 2

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 1,000.788

F2 · price: This transaction was executed in multiple trades at prices ranging from $123.360 to $124.280. 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: 0001127602-24-006799 · form4.xml · nonDerivative · entry 1

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 12,612.788

F1 · price: This transaction was executed in multiple trades at prices ranging from $122.250 to $123.200. 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: 0001127602-24-005321 · form4.xml · derivative · entry 13

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 25,670.843

Underlying: Common Stock · 2,762 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 Instruments, Inc.

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

F8 · 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.

F8 · 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: 0001127602-24-005321 · form4.xml · derivative · entry 12

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 28,432.843

Underlying: Common Stock · 6,791 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 Instruments, Inc.

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

F7 · 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.

F7 · 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: 0001127602-24-005321 · form4.xml · derivative · entry 11

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 35,223.843

Underlying: Common Stock · 2,430 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 Instruments, Inc.

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

F6 · derivative.exercise_date: These RSUs vest in three equal annual installments commencing on February 15, 2023, 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 vest in three equal annual installments commencing on February 15, 2023, 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: 0001127602-24-005321 · form4.xml · derivative · entry 10

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 37,653.843

Underlying: Common Stock · 4,129 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 Instruments, Inc.

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

F5 · derivative.exercise_date: These RSUs were subject to performance criteria, the achievement of which was determined on February 8, 2023, and thereafter vest in three equal annual installments beginning on February 15, 2023, 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 were subject to performance criteria, the achievement of which was determined on February 8, 2023, and thereafter vest in three equal annual installments beginning on February 15, 2023, 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: 0001127602-24-005321 · form4.xml · derivative · entry 9

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 41,782.843

Underlying: Common Stock · 1,525.164 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 Instruments, Inc.

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

F4 · derivative.exercise_date: These RSUs vest in three equal annual installments commencing on February 15, 2022, 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 vest in three equal annual installments commencing on February 15, 2022, 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: 0001127602-24-005321 · form4.xml · derivative · entry 8

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 43,308.007

Underlying: Common Stock · 3,728.956 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 Instruments, Inc.

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

F3 · derivative.exercise_date: These RSUs were subject to performance criteria, the achievement of which was determined on January 21, 2022, and thereafter vest in three equal annual installments beginning on February 15, 2022, 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 were subject to performance criteria, the achievement of which was determined on January 21, 2022, and thereafter vest in three equal annual installments beginning on February 15, 2022, 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: 0001127602-24-005321 · form4.xml · nonDerivative · entry 7

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 32,865.788

F2 · kind: These shares were withheld by MKS Instruments, 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: 0001127602-24-005321 · form4.xml · nonDerivative · entry 6

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 42,038.788

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 Instruments, Inc.

SEC source: 0001127602-24-005321 · form4.xml · nonDerivative · entry 5

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 39,276.788

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 Instruments, Inc.

SEC source: 0001127602-24-005321 · form4.xml · nonDerivative · entry 4

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 32,485.788

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 Instruments, Inc.

SEC source: 0001127602-24-005321 · form4.xml · nonDerivative · entry 3

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 30,055.788

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 Instruments, Inc.

SEC source: 0001127602-24-005321 · form4.xml · nonDerivative · entry 2

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 25,926.788

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 Instruments, Inc.

SEC source: 0001127602-24-005321 · form4.xml · nonDerivative · entry 1

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 24,401.624

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 Instruments, Inc.

SEC source: 0001127602-24-003527 · form4.xml · derivative · entry 1

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 47,036.963

Underlying: Common Stock · 20,374.788 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 Instruments, Inc.

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

F2 · 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.

F2 · 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: 0001127602-23-028822 · form4.xml · derivative · entry 5

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 26,662.175

Underlying: Common Stock · 350 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 Instruments, Inc.

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

F4 · derivative.exercise_date: Portion of 2023 RSU Award accelerated to satisfy FICA taxes.

F4 · derivative.expiration_date: Portion of 2023 RSU Award accelerated to satisfy FICA taxes.

SEC source: 0001127602-23-028822 · form4.xml · derivative · entry 4

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,012.175

Underlying: Common Stock · 349 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 Instruments, Inc.

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

F3 · derivative.exercise_date: Portion of 2022 RSU Award accelerated to satisfy FICA taxes.

F3 · derivative.expiration_date: Portion of 2022 RSU Award accelerated to satisfy FICA taxes.

SEC source: 0001127602-23-028822 · form4.xml · nonDerivative · entry 3

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,672.668

F2 · kind: Shares used to satisfy FICA taxes.

SEC source: 0001127602-23-028822 · form4.xml · nonDerivative · entry 2

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 21,371.668

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 Instruments, Inc.

SEC source: 0001127602-23-028822 · form4.xml · nonDerivative · entry 1

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 21,021.668

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 Instruments, Inc.

SEC source: 0001127602-23-023836 · form4.xml · nonDerivative · entry 2

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 20,546.596

F2 · price: This transaction was executed in multiple trades at prices ranging from $97.50 to $97.95. 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: 0001127602-23-023836 · form4.xml · nonDerivative · entry 1

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: No plan indicated

Ownership: Direct

Disclosed balance after: 27,619.596

F1 · price: This transaction was executed in multiple trades at prices ranging from $96.50 to $97.49. 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: 0001127602-23-005504 · form4.xml · derivative · entry 14

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 27,361.175

Underlying: Common Stock · 2,431 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 Instruments, Inc.

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

F9 · derivative.exercise_date: These RSUs vest in three equal annual installments commencing on February 15, 2023, 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, 2023, 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: 0001127602-23-005504 · form4.xml · derivative · entry 13

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 29,792.175

Underlying: Common Stock · 4,303 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 Instruments, Inc.

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

F8 · derivative.exercise_date: These RSUs were subject to performance criteria, the achievement of which was determined on February 8, 2023, and thereafter vest in three equal annual installments beginning on February 15, 2023, 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, 2023, and thereafter vest in three equal annual installments beginning on February 15, 2023, 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: 0001127602-23-005504 · form4.xml · derivative · entry 12

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 34,095.175

Underlying: Common Stock · 1,525 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 Instruments, Inc.

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

F7 · derivative.exercise_date: These RSUs vest in three equal annual installments commencing on February 15, 2022, 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, 2022, 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: 0001127602-23-005504 · form4.xml · derivative · entry 11

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 35,620.175

Underlying: Common Stock · 3,729 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 Instruments, Inc.

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

F6 · derivative.exercise_date: These RSUs were subject to performance criteria, the achievement of which was determined on January 21, 2022, and thereafter vest in three equal annual installments beginning on February 15, 2022, 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 January 21, 2022, and thereafter vest in three equal annual installments beginning on February 15, 2022, 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: 0001127602-23-005504 · form4.xml · derivative · entry 10

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 39,349.175

Underlying: Common Stock · 2,179.984 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 Instruments, Inc.

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

F5 · derivative.exercise_date: These RSUs vest in three equal annual installments commencing on February 15, 2021, 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, 2021, 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: 0001127602-23-005504 · form4.xml · derivative · entry 9

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 41,529.159

Underlying: Common Stock · 3,836.893 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 Instruments, Inc.

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

F4 · derivative.exercise_date: These RSUs were subject to performance criteria, the achievement of which was determined on January 25, 2021, and thereafter vest in three equal annual installments beginning on February 15, 2021, 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 January 25, 2021, and thereafter vest in three equal annual installments beginning on February 15, 2021, 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: 0001127602-23-005504 · form4.xml · derivative · entry 8

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 45,366.052

Underlying: Common Stock · 8,637.451 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 Instruments, Inc.

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

F3 · 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.

F3 · 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: 0001127602-23-005504 · form4.xml · nonDerivative · entry 7

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 45,396.5

F2 · kind: This transaction was effected pursuant to a Rule 10b5-1 trading plan previously adopted by the reporting person.

SEC source: 0001127602-23-005504 · form4.xml · nonDerivative · entry 6

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 52,372.5

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 Instruments, Inc.

SEC source: 0001127602-23-005504 · form4.xml · nonDerivative · entry 5

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 49,941.5

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 Instruments, Inc.

SEC source: 0001127602-23-005504 · form4.xml · nonDerivative · entry 4

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 45,638.5

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 Instruments, Inc.

SEC source: 0001127602-23-005504 · form4.xml · nonDerivative · entry 3

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 44,113.5

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 Instruments, Inc.

SEC source: 0001127602-23-005504 · form4.xml · nonDerivative · entry 2

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 40,384.5

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 Instruments, Inc.

SEC source: 0001127602-23-005504 · form4.xml · nonDerivative · entry 1

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 38,204.516

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 Instruments, Inc.

SEC source: 0001127602-23-004170 · form4.xml · derivative · entry 1

BAGSHAW SETH H · CIK 0001192439 · EVP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 36,728.601

Underlying: Common Stock · 12,911.585 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 Instruments, Inc.

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

F2 · derivative.exercise_date: These RSUs were subject to performance criteria, the achievement of which was determined on February 8, 2023, and thereafter vest in three equal annual installments beginning on February 15, 2023, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.

F2 · derivative.expiration_date: These RSUs were subject to performance criteria, the achievement of which was determined on February 8, 2023, and thereafter vest in three equal annual installments beginning on February 15, 2023, 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: 0001127602-22-026936 · form4.xml · derivative · entry 5

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 23,817.016

Underlying: Common Stock · 308 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 Instruments, Inc.

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

F4 · derivative.exercise_date: Portion of 2022 RSU Award accelerated to satisfy FICA taxes.

F4 · derivative.expiration_date: Portion of 2022 RSU Award accelerated to satisfy FICA taxes.

SEC source: 0001127602-22-026936 · form4.xml · derivative · entry 4

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 24,125.016

Underlying: Common Stock · 315 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 Instruments, Inc.

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

F3 · derivative.exercise_date: Portion of 2021 RSU Award accelerated to satisfy FICA taxes.

F3 · derivative.expiration_date: Portion of 2021 RSU Award accelerated to satisfy FICA taxes.

SEC source: 0001127602-22-026936 · form4.xml · nonDerivative · entry 3

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 34,367.623

F2 · kind: Shares used to satisfy FICA taxes.

SEC source: 0001127602-22-026936 · form4.xml · nonDerivative · entry 2

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 34,990.623

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 Instruments, Inc.

SEC source: 0001127602-22-026936 · form4.xml · nonDerivative · entry 1

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 34,682.623

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 Instruments, Inc.

SEC source: 0001127602-22-024521 · form4.xml · derivative · entry 3

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 24,440.016

Underlying: Common Stock · 4,358.058 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 Instruments, Inc.

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

F3 · derivative.exercise_date: These RSUs vest in two equal annual installments on each of the second anniversary and third anniversary of the date of grant, October 28, 2019.

F3 · derivative.expiration_date: These RSUs vest in two equal annual installments on each of the second anniversary and third anniversary of the date of grant, October 28, 2019.

SEC source: 0001127602-22-024521 · form4.xml · nonDerivative · entry 2

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 34,290.938

F2 · kind: This transaction was effected pursuant to a Rule 10b5-1 trading plan previously adopted by the reporting person.

SEC source: 0001127602-22-024521 · form4.xml · nonDerivative · entry 1

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 36,223.938

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 Instruments, Inc.

SEC source: 0001127602-22-012834 · form4.xml · derivative · entry 1

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 28,798.074

Underlying: Common Stock · 7,600.018 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 Instruments, Inc.

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

F2 · derivative.exercise_date: These RSUs vest in three equal annual installments commencing on February 15, 2023, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.

F2 · derivative.expiration_date: These RSUs vest in three equal annual installments commencing on February 15, 2023, 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: 0001127602-22-005304 · form4.xml · derivative · entry 13

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 21,198.056

Underlying: Common Stock · 1,525 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 Instruments, Inc.

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

F8 · derivative.exercise_date: These RSUs vest in three equal annual installments commencing on February 15, 2022, 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 vest in three equal annual installments commencing on February 15, 2022, 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: 0001127602-22-005304 · form4.xml · derivative · entry 12

BAGSHAW SETH H · CIK 0001192439 · Sr. VP, CFO & Treasurer

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 22,723.056

Underlying: Common Stock · 3,885 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 Instruments, Inc.

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

F7 · derivative.exercise_date: These RSUs were subject to performance criteria, the achievement of which was determined on January 21, 2022, and thereafter vest in three equal annual installments beginning on February 15, 2022, 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 were subject to performance criteria, the achievement of which was determined on January 21, 2022, and thereafter vest in three equal annual installments beginning on February 15, 2022, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.