MKS director sells 300 shares at $250.96

Under a Rule 10b5-1 plan, an open-market sale at $250.96 a share left her holding 18,845.353 MKS common shares after the transaction.

Rhea-AI Filing Summary

MKS INC (MKSI) director Elizabeth Mora reported selling 300 shares of common stock on September 1, 2026 in an open-market transaction at $250.96 per share. After this sale, she directly held 18,845.353 shares of MKS INC common stock. The transaction was effected under a Rule 10b5-1 trading plan adopted on February 23, 2026.

Insider Trade Summary 10b5-1

Net Seller: 300 shares

Net Sell 1 txn

Insider Mora Elizabeth

Role Director

Sold 300 shs ($75K)

Type	Security	Shares	Price	Value
Sale	Common Stock F1	300	$250.96	$75K

Holdings After Transaction: Common Stock — 18,845.353 shares (Direct)

Footnotes (1)

1. F1. This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 23, 2026.

Key Figures

Shares sold: 300 shares Sale price per share: $250.96 per share Shares held after transaction: 18,845.353 shares +1 more

4 metrics

Shares sold 300 shares Common stock sale by director Elizabeth Mora on September 1, 2026

Sale price per share $250.96 per share Price for the September 1, 2026 open-market sale

Shares held after transaction 18,845.353 shares Direct holdings of Elizabeth Mora following the reported sale

Rule 10b5-1 plan adoption date February 23, 2026 Date the trading plan covering the reported sale was adopted

Key Terms

Rule 10b5-1 trading plan, open-market transaction

2 terms

Rule 10b5-1 trading plan regulatory

"This transaction was effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on February 23, 2026."

A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.

open-market transaction market

"Sale in open market or private transaction"

An open-market transaction is a buy or sell of a company's shares or other securities conducted on a public exchange at the current market price, rather than through a private agreement. Investors watch these trades because they change the number of shares available and can move the price immediately—similar to how a large purchase at a busy store can raise demand and affect the checkout price—so such activity can signal market sentiment and alter ownership stakes.

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

What insider transaction did MKSI director Elizabeth Mora report on this Form 4?

Elizabeth Mora reported a sale of 300 shares of MKS INC common stock on September 1, 2026 in an open-market transaction at $250.96 per share, as disclosed in the Form 4.

How many MKSI shares does Elizabeth Mora hold after the reported transaction?

After the September 1, 2026 sale, Elizabeth Mora directly holds 18,845.353 shares of MKS INC common stock, according to the Form 4 disclosure.

Was the MKSI insider sale by Elizabeth Mora under a Rule 10b5-1 plan?

Yes. The Form 4 states the September 1, 2026 sale was effected pursuant to a Rule 10b5-1 trading plan adopted by Elizabeth Mora on February 23, 2026.

What price did Elizabeth Mora receive per MKSI share in the reported sale?

The Form 4 reports that Elizabeth Mora sold MKS INC common stock at a price of $250.96 per share on September 1, 2026 in the open market.

What is Elizabeth Mora’s role at MKS INC (MKSI)?

Elizabeth Mora is reported as a director of MKS INC in the Form 4 filing that discloses her September 1, 2026 sale of company common stock.

AI-generated analysis. How Rhea-AI works. Not financial advice.

Form 4 Insider Transactions: What Each Field Means →

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Available on EDGAR 09/02/2026 - 12:35 PM EDT Accepted by SEC EDGAR 09/02/2026 - 12:34 PM EDT Learn about SEC filing dates

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).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Mora Elizabeth

(Last) (First) (Middle)

C/O MKS INC.

2 TECH DRIVE

(Street)

ANDOVER MASSACHUSETTS 01810

(City) (State) (Zip)

UNITED STATES

(Country)

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)

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
09/01/2026

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

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

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

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	09/01/2026		S(1)		300	D	$250.96	18,845.353	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 February 23, 2026.

	/s/ M. Kathryn Rickards, attorney-in-fact	09/02/2026
	** 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.
* Form 4: SEC 1474 (03-26)