[SCHEDULE 13G] Mistras Group Inc. SEC Filing

Rhea-AI Filing Summary

Kristy Kyriakopoulos filed a Schedule 13G reporting beneficial ownership of 1,669,553 shares of Mistras Group, Inc. common stock, representing 5.3% of the outstanding class based on 31,538,050 shares. The filing states these shares are owned with sole voting and dispositive power and includes a certification that the holdings were not acquired to influence control of the issuer.

The report identifies the issuer by CUSIP 60649T107 and lists the issuer address in Princeton Junction, New Jersey. A power of attorney exhibit is attached and the filing is dated September 11, 2025.

Positive

• Reportable 5.3% stake in Mistras Group is disclosed, providing transparency about a significant shareholder position
• Sole voting and dispositive power reported for 1,669,553 shares, clarifying the filer controls voting of the shares
• Certification of passive intent indicates the holdings were not acquired to influence control, suggesting no stated activist agenda

Negative

• None.

Insights

Securities Analyst

TL;DR: A non-activist beneficial holder reports a meaningful 5.3% stake with sole voting and dispositive power.

The Schedule 13G indicates a substantial passive position by Ms. Kyriakopoulos equal to 1,669,553 shares or 5.3% of the class using 31,538,050 shares outstanding. The filing is consistent with a passive reporting obligation rather than an intent to control, as reflected in the certification language. For investors and corporate governance observers this filing signals a sizable shareholder but not an announced activism intent.

Corporate Governance Expert

TL;DR: Filing shows a reportable passive stake above 5% which may draw attention but lacks control intent.

The document shows sole voting and dispositive power over the reported shares which gives the holder clear authority over voting decisions. However, the filer certified the stake was not acquired to influence control, aligning with Rule 13d-1 disclosures for passive investors. The presence of a power of attorney exhibit documents the filing mechanics. This is material for disclosure purposes but not an immediate governance change.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

Mistras Group, Inc.

(Name of Issuer)

Common Stock, $0.01 par value

(Title of Class of Securities)

60649T107

(CUSIP Number)

07/08/2025

(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. 60649T107

1

Names of Reporting Persons

Kristy Kyriakopoulos

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

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

5	Sole Voting Power 1,669,553.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 1,669,553.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

1,669,553.00

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)

5.3 %

12

Type of Reporting Person (See Instructions)

IN

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Mistras Group, Inc.
(b)	Address of issuer's principal executive offices: 195 Clarksville Road, Princeton Junction, NJ, 08550
Item 2.
(a)	Name of person filing: Kristy Kyriakopoulos
(b)	Address or principal business office or, if none, residence: c/o Stephanie Foglia, Mistras Group, 195 Clarksville Road, Princeton Junction, New Jersey 08550
(c)	Citizenship: United States of America
(d)	Title of class of securities: Common Stock, $0.01 par value
(e)	CUSIP No.: 60649T107
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: 1,669,553.00
(b)	Percent of class: 5.3%* *This percentage calculation is based on 31,538,050 outstanding shares as of August 6, 2025.
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 1,669,553.00
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 1,669,553.00
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	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 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.

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.

Kristy Kyriakopoulos

Signature:	Kristy Kyriakopoulos
Name/Title:	Michael C. Keefe as attorney-in-fact for Kristy Kyriakopoulos
Date:	09/11/2025

Exhibit Information

EX-24.1 Power of Attorney

FAQ

How many Mistras Group (MG) shares does Kristy Kyriakopoulos own?

The filing reports 1,669,553 shares beneficially owned by Kristy Kyriakopoulos.

What percentage of Mistras Group does the 13G filing report?

The reported ownership equals 5.3% of the class based on 31,538,050 outstanding shares.

Does the filing indicate voting or dispositive power for the MG shares?

Yes. The filer reports sole voting power and sole dispositive power over the 1,669,553 shares.

Was the stake acquired to change or influence control of Mistras Group?

The filing includes a certification stating the shares were not acquired to change or influence control of the issuer.

What is the CUSIP and filing date listed in the Schedule 13G?

The CUSIP is 60649T107 and the signature block shows a date of September 11, 2025.