Ramakumar Mayampurath - 22 May 2026 Form 4 Insider Report for MKS INC (MKSI)

Reporting relationship: EVP & CFO
Issuer ticker: MKSI
Reported as of: 22 May 2026
Net transaction value: -$2,779,379
SEC form: 4
Accepted by SEC: 26 May 2026, 14:18:47 UTC
Prior SEC filing: 18 Feb 2026
Source filing: View source filing
Reporting owner signature: /s/ M. Kathryn Rickards, attorney-in-fact

Key filing fact

Ramakumar Mayampurath filed Form 4 for MKS INC (MKSI) on 26 May 2026.

Key facts

This page summarizes Ramakumar Mayampurath's Form 4 filing for MKS INC (MKSI).
1 reported transaction and 0 derivative rows are listed below.
Accepted by SEC: 26 May 2026, 14:18.

Change

Previous filing in this sequence was filed on 18 Feb 2026.
Current net transaction value: -$2,779,379.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001859332 Primary reporting owner

Mayampurath Ramakumar

Relationship: EVP & CFO
Address: C/O MKS INC., 2 TECH DRIVE, ANDOVER
Signature: /s/ M. Kathryn Rickards, attorney-in-fact
Signature date: 26 May 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

MKSI transaction

Common Stock

Sale

Transaction value: $2,779,379
Shares: -8,810
Change %: -100%
Price: $315.48
Shares after: 1
Date: 22 May 2026
Ownership: Direct
Footnotes: F1

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Rule 10b5-1 trading plan

These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.

Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).

Explanation of responses 1 footnote

Footnote F1

This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 20, 2026.