[Form 4] MKS INC Insider Trading Activity

Rhea-AI Filing Summary

MKS Inc. (MKSI) insider transaction: Director Jacqueline F. Moloney reported a sale of 300 shares of MKS common stock on 10/01/2025 at a price of $122.14 per share under a Rule 10b5-1 trading plan adopted 09/10/2024. After the reported sale the filing lists 11,562.304 shares beneficially owned by the reporting person, shown as direct ownership. The Form 4 was executed by an attorney-in-fact on 10/02/2025. The filing discloses this single non-derivative disposition and provides no other transactions or derivative holdings.

Insights

Financial Analyst

TL;DR: Routine insider sale executed under a pre-established 10b5-1 plan; transaction appears administrative rather than company-changing.

The report shows a small disposition of 300 common shares at $122.14 each, leaving 11,562.304 shares reported as beneficially owned by the director. The sale is documented as occurring under a Rule 10b5-1 trading plan adopted on 09/10/2024, which indicates the timing was pre-specified. No additional sales, purchases, or derivative positions are disclosed, and the filing does not provide financial performance or operational details to evaluate further impact.

Corporate Governance Expert

TL;DR: Governance disclosure is complete for this single transaction and cites a 10b5-1 trading plan.

The Form 4 identifies Jacqueline F. Moloney as a director and reports the disposition of 300 shares under a Rule 10b5-1 plan, with the plan adoption date disclosed. The form is signed by an attorney-in-fact on 10/02/2025, fulfilling signature requirements. The filing contains no indications of unusual trading patterns, related-party transactions, or changes in status that would raise immediate governance concerns based solely on the provided content.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person^*

Moloney Jacqueline F

(Last) (First) (Middle)

C/O MKS INC.

2 TECH DRIVE

(Street)

ANDOVER MA 01810

(City) (State) (Zip)

2. Issuer Name and Ticker or Trading Symbol
MKS INC [ MKSI ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director		10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
10/01/2025

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	10/01/2025		S(1)		300	D	$122.14	11,562.304	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on September 10, 2024.

	/s/ M. Kathryn Rickards, attorney-in-fact	10/02/2025
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.

FAQ

What insider transaction did MKSI director Jacqueline Moloney report?

The director reported a sale of 300 shares of MKSI common stock on 10/01/2025 at $122.14 per share.

Was the MKSI sale executed under a trading plan?

Yes. The transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on 09/10/2024.

How many MKSI shares did the reporting person beneficially own after the transaction?

The Form 4 lists 11,562.304 shares beneficially owned following the reported transaction.

Who signed the Form 4 for the MKSI reporting person?

The Form 4 was executed by M. Kathryn Rickards, attorney-in-fact on 10/02/2025.

Does the filing disclose any derivative securities or other transactions?

No. The filing contains only a single non-derivative disposition and shows no derivative securities or additional transactions.