MKSI

SEC source: 0001127602-21-013895 · form4.xml · nonDerivative · entry 1

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 27,010.407

F1 · kind: This transaction was effected pursuant to a Rule 10b5-1 trading plan previously adopted by the reporting person.

F2 · price: This transaction was executed in multiple trades at prices ranging from $184.02 to $184.90. 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: 0001127602-21-013887 · form4.xml · derivative · entry 3

Henry David Philip · CIK 0001842459 · SVP, Corp Mkt, PMO & Glob Svc

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,564.277

Underlying: Common Stock · 479 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 commencing on April 15, 2021, provided that if, in any vesting year, April 15th is not a business day, such vesting shall occur on the next business day.

F3 · derivative.expiration_date: These RSUs vest in two equal annual installments commencing on April 15, 2021, provided that if, in any vesting year, April 15th is not a business day, such vesting shall occur on the next business day.

SEC source: 0001127602-21-013887 · form4.xml · nonDerivative · entry 2

Henry David Philip · CIK 0001842459 · SVP, Corp Mkt, PMO & Glob Svc

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,089.58

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

SEC source: 0001127602-21-013887 · form4.xml · nonDerivative · entry 1

Henry David Philip · CIK 0001842459 · SVP, Corp Mkt, PMO & Glob Svc

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,230.58

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: 0001127602-21-013893 · form4.xml · derivative · entry 3

Taranto Eric Robert · CIK 0001842235 · SVP & GM, V&A Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,751.677

Underlying: Common Stock · 787 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 commencing on April 15, 2021, provided that if, in any vesting year, April 15th is not a business day, such vesting shall occur on the next business day.

F3 · derivative.expiration_date: These RSUs vest in two equal annual installments commencing on April 15, 2021, provided that if, in any vesting year, April 15th is not a business day, such vesting shall occur on the next business day.

SEC source: 0001127602-21-013893 · form4.xml · nonDerivative · entry 2

Taranto Eric Robert · CIK 0001842235 · SVP & GM, V&A Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,634.5164

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

SEC source: 0001127602-21-013893 · form4.xml · nonDerivative · entry 1

Taranto Eric Robert · CIK 0001842235 · SVP & GM, V&A Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,865.5164

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: 0001127602-21-013717 · form4.xml · derivative · entry 3

Gitin Mark Milton · CIK 0001842711 · SVP & GM, L&M Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 9,329.908

Underlying: Common Stock · 712.752 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 vested on April 13, 2021.

F3 · derivative.expiration_date: These RSUs vested on April 13, 2021.

SEC source: 0001127602-21-013717 · form4.xml · nonDerivative · entry 2

Gitin Mark Milton · CIK 0001842711 · SVP & GM, L&M Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,803.054

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

SEC source: 0001127602-21-013717 · form4.xml · nonDerivative · entry 1

Gitin Mark Milton · CIK 0001842711 · SVP & GM, L&M Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,050.054

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: 0001127602-21-013723 · form4.xml · derivative · entry 3

Taranto Eric Robert · CIK 0001842235 · SVP & GM, V&A Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,538.677

Underlying: Common Stock · 627.342 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 vested on April 13, 2021.

F3 · derivative.expiration_date: These RSUs vested on April 13, 2021.

SEC source: 0001127602-21-013723 · form4.xml · nonDerivative · entry 2

Taranto Eric Robert · CIK 0001842235 · SVP & GM, V&A Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,078.5164

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

SEC source: 0001127602-21-013723 · form4.xml · nonDerivative · entry 1

Taranto Eric Robert · CIK 0001842235 · SVP & GM, V&A Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,263.5164

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: 0001127602-21-013719 · form4.xml · derivative · entry 3

Henry David Philip · CIK 0001842459 · SVP, Corp Mkt, PMO & Glob Svc

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,043.277

Underlying: Common Stock · 356.376 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 vested on April 13, 2021.

F3 · derivative.expiration_date: These RSUs vested on April 13, 2021.

SEC source: 0001127602-21-013719 · form4.xml · nonDerivative · entry 2

Henry David Philip · CIK 0001842459 · SVP, Corp Mkt, PMO & Glob Svc

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,751.58

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

SEC source: 0001127602-21-013719 · form4.xml · nonDerivative · entry 1

Henry David Philip · CIK 0001842459 · SVP, Corp Mkt, PMO & Glob Svc

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,856.58

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: 0001127602-21-014262 · form4a.xml · nonDerivative · entry 1

Gitin Mark Milton · CIK 0001842711 · SVP & GM, L&M Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 4,733.054

F1 · kind: This transaction was effected pursuant to a Rule 10b5-1 trading plan previously adopted by the reporting person.

F2 · shares: The original Form 4 filed on April 14, 2021 (the "Original Form 4"), is hereby amended solely to correct an error in the number of shares of common stock of MKS Instruments, Inc. that were withheld from the reporting person for the payment of tax liabilities. Please note that the 70 additional shares that should have been reported as withheld for the payment of tax liabilities on the Original Form 4 were included in the reporting person's holdings in a subsequent Form 4 filed on April 21, 2021. The reporting person will exclude these shares from the reporting person's holdings in future filings.

SEC source: 0001127602-21-011393 · form4.xml · nonDerivative · entry 1

Moloney Jacqueline F · CIK 0001501968 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 7,791.49

SEC source: 0001127602-21-008685 · form4.xml · nonDerivative · entry 1

Mora Elizabeth · CIK 0001548935 · Director

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 14,601.314

F1 · kind: This transaction was effected pursuant to a Rule 10b5-1 trading plan previously adopted by the reporting person.

SEC source: 0001127602-21-006373 · form4.xml · derivative · entry 1

Gitin Mark Milton · CIK 0001842711 · SVP & GM, L&M Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 10,042.66

Underlying: Common Stock · 1,655.052 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, 2022, 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, 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: 0001127602-21-006384 · form4.xml · derivative · entry 1

Taranto Eric Robert · CIK 0001842235 · SVP & GM, V&A Division

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,166.019

Underlying: Common Stock · 1,161.44 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, 2022, 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, 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: 0001127602-21-006365 · form4.xml · derivative · entry 4

Henry David Philip · CIK 0001842459 · SVP, Corp Mkt, PMO & Glob Svc

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 5,399.653

Underlying: Common Stock · 1,170 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, 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 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: 0001127602-21-006365 · form4.xml · derivative · entry 3

Henry David Philip · CIK 0001842459 · SVP, Corp Mkt, PMO & Glob Svc

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 6,569.653

Underlying: Common Stock · 1,742.16 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, 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 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: 0001127602-21-006365 · form4.xml · nonDerivative · entry 2

Henry David Philip · CIK 0001842459 · SVP, Corp Mkt, PMO & Glob Svc

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,500.204

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

SEC source: 0001127602-21-006365 · form4.xml · nonDerivative · entry 1

Henry David Philip · CIK 0001842459 · SVP, Corp Mkt, PMO & Glob Svc

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 1,844.204

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: 0001127602-21-006359 · form4.xml · derivative · entry 6

Schreiner James Alan · CIK 0001797189 · Sr. VP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,221.142

Underlying: Common Stock · 695 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: 0001127602-21-006359 · form4.xml · derivative · entry 5

Schreiner James Alan · CIK 0001797189 · Sr. VP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 8,916.142

Underlying: Common Stock · 1,001 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: 0001127602-21-006359 · form4.xml · derivative · entry 4

Schreiner James Alan · CIK 0001797189 · Sr. VP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 9,917.142

Underlying: Common Stock · 1,959.93 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, 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 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: 0001127602-21-006359 · form4.xml · nonDerivative · entry 3

Schreiner James Alan · CIK 0001797189 · Sr. VP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,210

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

SEC source: 0001127602-21-006359 · form4.xml · nonDerivative · entry 2

Schreiner James Alan · CIK 0001797189 · Sr. VP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,708

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: 0001127602-21-006359 · form4.xml · nonDerivative · entry 1

Schreiner James Alan · CIK 0001797189 · Sr. VP & COO

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 2,013

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: 0001127602-21-006350 · form4.xml · derivative · entry 14

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 31,427.701

Underlying: Common Stock · 2,180 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, 2021, 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, 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: 0001127602-21-006350 · form4.xml · derivative · entry 13

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 33,607.701

Underlying: Common Stock · 3,999 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 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.

F8 · 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: 0001127602-21-006350 · form4.xml · derivative · entry 12

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 37,606.701

Underlying: Common Stock · 2,642.821 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, 2020, 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, 2020, 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: 0001127602-21-006350 · form4.xml · derivative · entry 11

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 40,249.522

Underlying: Common Stock · 2,941.722 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 27, 2020, and thereafter vest in three equal installments beginning on February 15, 2020, 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 27, 2020, and thereafter vest in three equal installments beginning on February 15, 2020, 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: 0001127602-21-006350 · form4.xml · derivative · entry 10

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 43,191.244

Underlying: Common Stock · 1,870.585 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, 2019, 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, 2019, 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: 0001127602-21-006350 · form4.xml · derivative · entry 9

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 45,061.829

Underlying: Common Stock · 2,201.689 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 28, 2019, and thereafter vest in three equal annual installments beginning on February 15, 2019, 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 28, 2019, and thereafter vest in three equal annual installments beginning on February 15, 2019, 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: 0001127602-21-006350 · form4.xml · derivative · entry 8

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 47,263.518

Underlying: Common Stock · 4,769.164 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, 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 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: 0001127602-21-006350 · form4.xml · nonDerivative · entry 7

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 28,410.407

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

SEC source: 0001127602-21-006350 · form4.xml · nonDerivative · entry 6

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 35,124.407

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: 0001127602-21-006350 · form4.xml · nonDerivative · entry 5

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 32,944.407

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: 0001127602-21-006350 · form4.xml · nonDerivative · entry 4

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 28,945.407

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: 0001127602-21-006350 · form4.xml · nonDerivative · entry 3

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 26,302.586

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: 0001127602-21-006350 · form4.xml · nonDerivative · entry 2

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 23,360.864

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: 0001127602-21-006350 · form4.xml · nonDerivative · entry 1

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

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 21,490.279

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: 0001127602-21-006352 · form4.xml · derivative · entry 14

Burke Kathleen Flaherty · CIK 0001775435 · Sr. VP, GC & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 16,522.579

Underlying: Common Stock · 1,280 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, 2021, 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, 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: 0001127602-21-006352 · form4.xml · derivative · entry 13

Burke Kathleen Flaherty · CIK 0001775435 · Sr. VP, GC & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 17,802.579

Underlying: Common Stock · 1,844 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 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.

F8 · 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: 0001127602-21-006352 · form4.xml · derivative · entry 12

Burke Kathleen Flaherty · CIK 0001775435 · Sr. VP, GC & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 19,646.579

Underlying: Common Stock · 1,574.183 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, 2020, 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, 2020, 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: 0001127602-21-006352 · form4.xml · derivative · entry 11

Burke Kathleen Flaherty · CIK 0001775435 · Sr. VP, GC & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 21,220.762

Underlying: Common Stock · 1,290.83 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 27, 2020, and thereafter vest in three equal installments beginning on February 15, 2020, 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 27, 2020, and thereafter vest in three equal installments beginning on February 15, 2020, 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: 0001127602-21-006352 · form4.xml · derivative · entry 10

Burke Kathleen Flaherty · CIK 0001775435 · Sr. VP, GC & Secretary

10b5-1 filing: Not disclosed

Ownership: Direct

Disclosed balance after: 22,511.592

Underlying: Common Stock · 1,050.315 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.

F5 · derivative.exercise_date: These RSUs vest in three equal annual installments commencing on February 15, 2019, 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, 2019, provided that if, in any vesting year, February 15th is not a business day, such vesting shall occur on the next business day.