# EDGAR Filing Document

**Accession Number:** 0001473735
**File Stem:** 0001436126-26-000050
**Filing Date:** 2026-3
**Character Count:** 11603
**Document Hash:** 0e9d47d4f02ed74421c6beac131eb132
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001436126-26-000050.hdr.sgml**: 20260310

**ACCESSION NUMBER**: 0001436126-26-000050

**CONFORMED SUBMISSION TYPE**: 4

**PUBLIC DOCUMENT COUNT**: 2

**CONFORMED PERIOD OF REPORT**: 20260304

**FILED AS OF DATE**: 20260310

**DATE AS OF CHANGE**: 20260310

**REPORTING-OWNER**: 

**OWNER DATA:**
- **COMPANY CONFORMED NAME:** Stamatakis Manuel N.
- **CENTRAL INDEX KEY:** 0001473735

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** 4
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 001-34481
- **FILM NUMBER:** 26738824

**MAIL ADDRESS:**
- **STREET 1:** C/O MISTRAS GROUP, INC.
- **STREET 2:** 195 CLARKSVILLE ROAD
- **CITY:** PRINCETON JUNCTION
- **STATE:** NJ
- **ZIP:** 08550
**ISSUER**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Mistras Group, Inc.
- **CENTRAL INDEX KEY:** 0001436126
- **STANDARD INDUSTRIAL CLASSIFICATION:** SERVICES-ENGINEERING SERVICES [8711]
- **ORGANIZATION NAME:** 07 Trade & Services
- **EIN:** 223341267
- **STATE OF INCORPORATION:** DE
- **FISCAL YEAR END:** 1231

**BUSINESS ADDRESS:**
- **STREET 1:** 195 CLARKSVILLE ROAD
- **CITY:** PRINCETON JUNCTION
- **STATE:** NJ
- **ZIP:** 08550
- **BUSINESS PHONE:** 609-716-4000

**MAIL ADDRESS:**
- **STREET 1:** 195 CLARKSVILLE ROAD
- **CITY:** PRINCETON JUNCTION
- **STATE:** NJ
- **ZIP:** 08550

## Ex-24

```

POWER OF ATTORNEY

I, the undersigned, being a person required to file reports pursuant to
Section?16 of the Securities Exchange Act of 1934 (?Section 16?)
regarding the undersigned?s beneficial ownership of equity securities
in Mistras?Group, Inc. (the??Company?), hereby constitute and appoint
each of Michael Keefe, Eileen Coggins, Laura Boswell and Michael Kozole,
signing singly, as my true and lawful attorney-in-fact to:

1. Take such actions as may be necessary or appropriate to enable the
undersigned to submit and file forms, schedules and other documents
with the U.S. Securities and Exchange Commission (?SEC?) utilizing
the SEC?s Electronic Data Gathering and Retrieval (?EDGAR?) system,
which actions may include (a) enrolling the undersigned in EDGAR Next
and (b) preparing, executing and submitting to the SEC a Form ID,
amendments thereto, and such other documents and information as may be
necessary or appropriate to obtain codes and passwords enabling the
undersigned to make filings and submissions utilizing the EDGAR system;

2. Prepare and execute any and all forms, schedules and other documents
(including any amendments thereto) the undersigned is required to file
with the SEC, or which the Attorney-in-Fact considers it advisable for
the undersigned to file with the SEC, under Section 13 or Section 16
of the Securities Exchange Act of 1934 or any rule or regulation
thereunder, or under Rule 144 under the Securities Act of 1933
(?Rule 144?), including Forms 3, 4 and 5, Schedules 13D and 13G, and
Forms 144 (all such forms, schedules and other documents being
referred to herein as ?SEC Filings?);

3. Submit and file SEC Filings with the SEC utilizing the EDGAR
system or cause them to be submitted and filed by a person appointed
under Section 5 below;

4. File, submit or otherwise deliver SEC Filings to any securities
exchange on which the Company?s securities may be listed or traded;

5. Act as an account administrator for the undersigned?s EDGAR account,
including: (i) appoint, remove and replace account administrators,
account users, technical administrators and delegated entities;
(ii) maintain the security of the undersigned?s EDGAR account,
including modification of access codes; (iii) maintain, modify and
certify the accuracy of information on the undersigned?s EDGAR account
dashboard; (iv) act as the EDGAR point of contact with respect to the
undersigned?s EDGAR account; and (v) any other actions contemplated by
Rule 10 of Regulation S-T with respect to account administrators;

6. Cause the Company to accept a delegation of authority from any of
the undersigned?s EDGAR account administrators and, pursuant to that
delegation, authorize the Company?s EDGAR account administrators
to appoint, remove or replace users for the undersigned?s
EDGAR account; and

7. Obtain, as the undersigned's representative and on the
undersigned's behalf, information regarding transactions in the
Company's equity securities from any third party, including the
Company and any brokers, dealers, employee benefit plan
administrators and trustees, and the undersigned hereby
authorizes any such third party to release any such information to
the Attorney-in-Fact.

8. The undersigned acknowledges that:

a. This Power of Attorney authorizes, but does not require, the
Attorney-in-Fact to act in his or her discretion on information
provided to such Attorney-in-Fact without independent verification of
such information;
b. Any documents prepared or executed by the Attorney-in-Fact on
behalf of the undersigned pursuant to this Power of Attorney will be
in such form and will contain such information as the Attorney-in-Fact,
in his or her discretion, deems necessary or desirable;
c. Neither the Company nor the Attorney-in-Fact assumes any liability
for the undersigned's responsibility to comply with the requirements
of Section 13 or Section 16 of the Exchange Act or Rule 144, any
liability of the undersigned for any failure to comply with such
requirements, or any liability of the undersigned for disgorgement of
profits under Section 16(b) of the Exchange Act; and
d. This Power of Attorney does not relieve the undersigned from
responsibility for compliance with the undersigned's obligations under
Section 13 or Section 16 of the Exchange Act, including, without
limitation, the reporting requirements under Section 13 or Section 16
of the Exchange Act.

9. The undersigned hereby grants to the Attorney-in-Fact full power
and authority to do and perform each and every act and thing requisite,
necessary or advisable to be done in connection with the foregoing,
as fully, to all intents and purposes, as the undersigned might or
could do in person, hereby ratifying and confirming all that the
Attorney-in-Fact, or his or her substitute or substitutes, shall
lawfully do or cause to be done by authority of this Power of Attorney.

10. This Power of Attorney shall remain in full force and effect until
the undersigned is no longer required to file Forms 4 or 5 or Schedules
13D or 13G or Forms 144 with respect to the undersigned's holdings of
and transactions in securities of the Company, unless earlier revoked
by the undersigned in a signed writing delivered to the
Attorney-in-Fact. This Power of Attorney revokes all previous
powers of attorney with respect to the subject matter of this
Power of Attorney.

This Power of Attorney shall remain in full force and effect until I
am no longer required to file Forms 3, 4, and 5 with respect to my
holdings of and transactions in securities of the Company, unless
earlier revoked by me.  By executing this Power of Attorney, I
revoke all powers of attorney previously executed by me regarding
the powers and authority granted in this Power of Attorney.

Dated:  September 18, 2025

					/S/ Manuel N. Stamatakis
					   Manuel N. Stamatakis

```

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

## FORM 4

### STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

[ ] 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**<sup>*</sup><br>Stamatakis Manuel N.<br><sub>(Last) (First) (Middle)</sub><br>C/O MISTRAS GROUP, INC.<br>195 CLARKSVILLE ROAD<br><sub>(Street)</sub><br>PRINCETON JUNCTION, NJ 08550<br><sub>(City) (State) (Zip)</sub> | **3. Date of Earliest Transaction (Month/Day/Year)**<br>2026-03-04 | **5. Relationship of Reporting Person(s) to Issuer**<br>(Check all applicable)<br>[X] Director [ ] 10% Owner<br>[X] Officer (give title below) [ ] Other (specify below)<br>_Executive Chairman_ |
| **2. Issuer Name and Ticker or Trading Symbol**<br>Mistras Group, Inc. [ MG ] | **4. If Amendment, Date of Original Filed (Month/Day/Year)**<br>  | **6. Individual or Joint/Group Filing (Check Applicable Line)**<br>[X] Form filed by One Reporting Person<br>[ ] Form filed by More than One Reporting Person |

---

## Table I - Non-Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | 3. Transaction Code (V) | 3. Transaction Code (V) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 4. Securities Acquired (A) or Disposed of (D) | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| 1. Title of Security | 2. Transaction Date | 2A. Deemed Execution Date | Code | V | Amount | (A) or (D) | Price | 5. Amount of Securities Beneficially Owned | 6. Ownership Form | 7. Nature of Indirect Beneficial Ownership |
| Common Stock | 2026-03-04 |  | F |  | 814<sup>(1)</sup> | D | $15.68 | 509795 | D |  |

---

## Table II - Derivative Securities

---

|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | 4. Transaction Code (V) | 4. Transaction Code (V) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 5. Number of Derivative Securities Acquired (A) or Disposed of (D) | 6. Date Exercisable and Expiration Date | 6. Date Exercisable and Expiration Date | 7. Title and Amount of Underlying Securities | 7. Title and Amount of Underlying Securities | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
| 1. Title of Derivative Security | 2. Conversion or Exercise Price | 3. Transaction Date | 3A. Deemed Execution Date | Code | V | (A) | (D) | Date Exercisable | Expiration Date | Title | Amount or Number of Shares | 8. Price of Derivative Security | 9. Number of Derivative Securities Beneficially Owned | 10. Ownership Form | 11. Nature of Indirect Beneficial Ownership |
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

---

### Footnotes:

(1) Represents an award of restricted stock units that will vest 100% on the first anniversary date of the grant.

**Signature:** /s/ Laura Boswell, attorney-in-fact for Manuel Stamatakis  
**Date:** 2026-03-10

### Remarks:

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.**