T. Rowe Price discloses 4.1% MKS Inc (MKSI) ownership stake

Rhea-AI Filing Summary

T. Rowe Price Associates, Inc. filed an amended Schedule 13G reporting its beneficial ownership of MKS Inc common stock as of 12/31/2025. The firm reports beneficial ownership of 2,753,871 shares, representing 4.1% of the outstanding common stock.

T. Rowe Price Associates has sole voting power over 2,736,929 shares and sole dispositive power over 2,753,850 shares, with no shared voting or dispositive power. The filer notes it owns 5 percent or less of the class and certifies the shares were acquired and are held in the ordinary course of business, not for the purpose of changing or influencing control of MKS Inc, while expressly denying beneficial ownership beyond what is reported.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 5)

MKS Inc

(Name of Issuer)

COMMON STOCK

(Title of Class of Securities)

55306N104

(CUSIP Number)

12/31/2025

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

Rule 13d-1(b)

Rule 13d-1(c)

Rule 13d-1(d)

SCHEDULE 13G

CUSIP No. 55306N104

1

Names of Reporting Persons

T. Rowe Price Associates, Inc.

2

Check the appropriate box if a member of a Group (see instructions)

(a)
(b)

3

Sec Use Only

4

Citizenship or Place of Organization

MARYLAND

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 2,736,929.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 2,753,850.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

2,753,871.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

4.1 %

12

Type of Reporting Person (See Instructions)

IA

SCHEDULE 13G

Item 1.
(a)	Name of issuer: MKS Inc
(b)	Address of issuer's principal executive offices: 2 TECH DRIVE, SUITE 201, ANDOVER, MA, 01810
Item 2.
(a)	Name of person filing: T. Rowe Price Associates, Inc.
(b)	Address or principal business office or, if none, residence: 1307 Point Street, Baltimore, MD 21231
(c)	Citizenship: Maryland
(d)	Title of class of securities: COMMON STOCK
(e)	CUSIP No.: 55306N104
Item 3.	If this statement is filed pursuant to §§ 240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:
(a)	Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o);
(b)	Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);
(c)	Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c);
(d)	Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);
(e)	An investment adviser in accordance with § 240.13d-1(b)(1)(ii)(E);
(f)	An employee benefit plan or endowment fund in accordance with § 240.13d-1(b)(1)(ii)(F);
(g)	A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);
(h)	A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);
(i)	A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);
(j)	A non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: 2753871
(b)	Percent of class: 4.1 %
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 2736929
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 2753850
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	Ownership of 5 Percent or Less of a Class.
	Ownership of 5 percent or less of a class
Item 6.	Ownership of more than 5 Percent on Behalf of Another Person.
	Not Applicable
Item 7.	Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company or Control Person.
	Not Applicable
Item 8.	Identification and Classification of Members of the Group.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under ?? 240.14a-11. T. Rowe Price Associates, Inc. hereby declares and affirms that the filing of Schedule 13G shall not be construed as an admission that Price Associates is the beneficial owner of the securities referred to, which beneficial ownership is expressly denied.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

T. Rowe Price Associates, Inc.

Signature:	Ellen York
Name/Title:	Vice President
Date:	02/17/2026

FAQ

What stake in MKS Inc (MKSI) does T. Rowe Price Associates report?

T. Rowe Price Associates reports beneficial ownership of 2,753,871 MKS Inc shares, or 4.1% of the common stock. This reflects its position as of December 31, 2025, based on a Schedule 13G/A filing describing its institutional investment stake.

How much voting power does T. Rowe Price Associates have in MKS Inc (MKSI)?

T. Rowe Price Associates has sole voting power over 2,736,929 MKS Inc common shares. It reports no shared voting power, indicating all reported voting authority resides solely with the firm for these holdings as of December 31, 2025.

What percentage of MKS Inc (MKSI) shares does T. Rowe Price Associates own?

T. Rowe Price Associates reports beneficial ownership of 4.1% of MKS Inc’s common stock. That percentage corresponds to 2,753,871 shares as disclosed in its amended Schedule 13G filing dated as of December 31, 2025.

Does T. Rowe Price Associates seek to influence control of MKS Inc (MKSI)?

The filing states the securities were acquired and are held in the ordinary course of business, not to change or influence control. It further notes the holdings are not in connection with any control-related transaction, consistent with passive investment intent.

What dispositive power over MKS Inc (MKSI) shares does T. Rowe Price report?

T. Rowe Price Associates reports sole dispositive power over 2,753,850 MKS Inc shares. It discloses no shared dispositive power, meaning decisions to sell or otherwise dispose of these shares rest solely with the firm for the reported holdings.

Does T. Rowe Price Associates claim full beneficial ownership of its MKS Inc (MKSI) holdings?

The filing expressly denies that T. Rowe Price Associates is the beneficial owner beyond what is reported. It states the filing should not be construed as an admission of beneficial ownership of the securities referenced in the Schedule 13G/A.