MKS Inc (NASDAQ: MKSI) grants 781.959 RSUs to director Mora

Rhea-AI Filing Summary

Mora Elizabeth reported acquisition or exercise transactions in this Form 4 filing.

MKS Inc director Elizabeth Mora reported an equity award of restricted stock units. On May 11, 2026, she received 781.959 restricted stock units of MKS Inc common stock as a grant, not a market purchase or sale, at a stated price of $0.00 per unit.

The units become fully vested on the day before the first annual meeting of shareholders following the grant date, or on the 13‑month anniversary of the grant if no such meeting occurs within that period. Each unit represents the right to receive one share of MKS Inc common stock, and after this award she holds 19,445.353 shares directly.

Insider Trade Summary

1 transaction reported

Mixed 1 txn

Insider Mora Elizabeth

Role null

Type	Security	Shares	Price	Value
Grant/Award	Common Stock	781.959	$0.00	--

Holdings After Transaction: Common Stock — 19,445.353 shares (Direct, null)

Footnotes (1)

1. These restricted stock units become fully vested on the day prior to the first annual meeting of shareholders following the date of grant (or if no such meeting is held within 13 months after the date of grant, on the 13 month anniversary of the date of grant). Each restricted stock unit represents the contingent right to receive one share of common stock of MKS Inc.

Key Figures

RSU grant size: 781.959 units Grant price per unit: $0.00 per unit Shares after transaction: 19,445.353 shares +1 more

4 metrics

RSU grant size 781.959 units Restricted stock units granted on May 11, 2026

Grant price per unit $0.00 per unit Stated transaction price for RSU award

Shares after transaction 19,445.353 shares Common stock directly owned after RSU grant

Vesting deadline alternative 13 months If no annual meeting within 13 months of grant date

Key Terms

restricted stock units, annual meeting of shareholders, contingent right, common stock

4 terms

restricted stock units financial

"These restricted stock units become fully vested on the day prior to the first annual meeting of shareholders"

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

annual meeting of shareholders financial

"on the day prior to the first annual meeting of shareholders following the date of grant"

A yearly gathering where a company’s owners (shareholders) vote on key items like electing the board, approving executive pay, and ratifying auditors, and receive updates on performance and strategy. Think of it as an annual town hall for owners: it matters to investors because outcomes and disclosures can affect leadership, corporate direction, dividend and governance policies, and therefore the company’s risk and potential return.

contingent right financial

"Each restricted stock unit represents the contingent right to receive one share of common stock"

common stock financial

"Each restricted stock unit represents the contingent right to receive one share of common stock of MKS Inc."

Common stock represents ownership shares in a company, giving investors a stake in its success and a say in important decisions through voting rights. It is the most common type of stock traded on markets and can provide income through dividends, as well as potential for value growth. For investors, holding common stock means sharing in the company’s profits and risks.

Form 4 Insider Transactions: What Each Field Means →

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).

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)
05/11/2026

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	05/11/2026		A(1)		781.959	A	(2)	19,445.353	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. These restricted stock units become fully vested on the day prior to the first annual meeting of shareholders following the date of grant (or if no such meeting is held within 13 months after the date of grant, on the 13 month anniversary of the date of grant).

2. Each restricted stock unit represents the contingent right to receive one share of common stock of MKS Inc.

	/s/ M. Kathryn Rickards, attorney-in-fact	05/12/2026
	** 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)

FAQ

What insider transaction did MKS Inc (MKSI) director Elizabeth Mora report?

Elizabeth Mora reported receiving an equity award of 781.959 restricted stock units of MKS Inc common stock. The Form 4 describes this as a grant or award acquisition rather than an open-market purchase or sale, and the stated price per unit is $0.00.

How many MKS Inc restricted stock units did Elizabeth Mora receive?

Elizabeth Mora received 781.959 restricted stock units of MKS Inc common stock. This equity award is classified as a grant or award acquisition, with each unit representing the right to receive one share of common stock when the units ultimately settle in stock.

When do Elizabeth Mora’s MKSI restricted stock units vest?

The restricted stock units become fully vested the day before the first annual meeting of shareholders following the grant date. If no annual meeting occurs within 13 months of the grant, vesting instead happens on the 13‑month anniversary of the grant date under the award terms.

What does each restricted stock unit from MKS Inc represent?

Each restricted stock unit represents a contingent right to receive one share of MKS Inc common stock. This means the units do not immediately deliver shares but convert into common stock when vesting conditions are satisfied and the award is settled according to its terms.

How many MKS Inc shares does Elizabeth Mora hold after this award?

After the reported restricted stock unit grant, Elizabeth Mora holds 19,445.353 shares of MKS Inc common stock directly. This figure reflects her direct ownership position as shown following the transaction in the Form 4, giving context for the size of the new equity grant.

Was Elizabeth Mora’s MKS Inc Form 4 transaction a stock purchase or sale?

The Form 4 classifies the transaction as a grant or award acquisition, not a market purchase or sale. Code “A” indicates a grant of 781.959 restricted stock units at a stated price of $0.00, typical of director equity compensation rather than open-market trading.