MKS INC — Director's Dealing 2025

Feb 19, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MKS INSTRUMENTS INC (MKSI)
CIK: 0001049502
Period of Report: 2025-02-18

Reporting Person: Taranto Eric Robert (EVP & GM, VSD)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-02-18	Common Stock	M	1118.659	—	Acquired	14420.9964	Direct
2025-02-18	Common Stock	M	804.704	—	Acquired	15225.7004	Direct
2025-02-18	Common Stock	M	1764	—	Acquired	16989.7004	Direct
2025-02-18	Common Stock	M	914	—	Acquired	17903.7004	Direct
2025-02-18	Common Stock	M	347.82	—	Acquired	18251.5204	Direct
2025-02-18	Common Stock	M	975	—	Acquired	19226.5204	Direct
2025-02-18	Common Stock	F	1760	$103.67	Disposed	17466.5204	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2025-02-18	Restricted Stock Unit	$	A	3911.065	Acquired		Common Stock (3911.065)	Direct
2025-02-18	Restricted Stock Unit	$	M	1118.659	Disposed		Common Stock (1118.659)	Direct
2025-02-18	Restricted Stock Unit	$	M	804.704	Disposed		Common Stock (804.704)	Direct
2025-02-18	Restricted Stock Unit	$	M	1764	Disposed		Common Stock (1764)	Direct
2025-02-18	Restricted Stock Unit	$	M	914	Disposed		Common Stock (914)	Direct
2025-02-18	Restricted Stock Unit	$	M	347.82	Disposed		Common Stock (347.82)	Direct
2025-02-18	Restricted Stock Unit	$	M	975	Disposed		Common Stock (975)	Direct

Footnotes

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

F2: 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.

F3: 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.

F4: 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: 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: 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: 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: 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.

F9: 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.