# EDGAR Filing Document

**Accession Number:** 0001436126
**File Stem:** 0001104659-26-073638
**Filing Date:** 2026-6
**Character Count:** 9123
**Document Hash:** 362be98b29b09ad40ae3c44a20d357cb
**Contains OCR:** False
**Source Format:** 

## Filing Content

## Filing Summary
**0001104659-26-073638.hdr.sgml**: 20260612

**ACCESSION NUMBER**: 0001104659-26-073638

**CONFORMED SUBMISSION TYPE**: SCHEDULE 13D/A

**PUBLIC DOCUMENT COUNT**: 1

**FILED AS OF DATE**: 20260612

**DATE AS OF CHANGE**: 20260612

**SUBJECT COMPANY**: 

**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

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A
- **SEC ACT:** 1934 Act
- **SEC FILE NUMBER:** 005-85079
- **FILM NUMBER:** 261088566

**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
**FILED BY**: 

**COMPANY DATA:**
- **COMPANY CONFORMED NAME:** Foglia Stephanie Athena
- **CENTRAL INDEX KEY:** 0002082289

**ORGANIZATION NAME:**

**FILING VALUES:**
- **FORM TYPE:** SCHEDULE 13D/A

**MAIL ADDRESS:**
- **STREET 1:** 504 HIRAM ROAD
- **CITY:** PLYMOUTH MEETING
- **STATE:** PA
- **ZIP:** 19462

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

## SCHEDULE 13D

### Under the Securities Exchange Act of 1934

**(Amendment No. 2)**

**Mistras Group, Inc.**

*(Name of Issuer)*

**Common Stock, $0.01 par value**

*(Title of Class of Securities)*

**—**

*(CUSIP Number)*

**Stephanie Foglia**<br>504 HIRAM ROAD<br>PLYMOUTH MEETING PA 19462<br>610-324-6463

*(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)*

**06/10/2026**

*(Date of Event Which Requires Filing of this Statement)*

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**Stephanie Foglia** | Name of reporting person<br>**Stephanie Foglia** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**X1** | Citizenship or place of organization<br>**X1** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**1606324.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**4310811.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**1606324.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**4310811.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**5917135.00** | Aggregate amount beneficially owned by each reporting person<br>**5917135.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**18.60%** | Percent of class represented by amount in Row (11)<br>**18.60%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**IN** | Type of Reporting Person (See Instructions)<br>**IN** | |

---

| **CUSIP No.** | **—** |

---

| | | | |
|:--|:--|:--|:--|
| 1 | Name of reporting person<br>**2025 Irrevocable Two-Year Grantor Retained Annuity Trust of Aspasia F. Vahaviolos** | Name of reporting person<br>**2025 Irrevocable Two-Year Grantor Retained Annuity Trust of Aspasia F. Vahaviolos** | |
| 2 | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | Check the appropriate box if a member of a Group (See Instructions)<br>[x] (a)<br>[ ] (b) | |
| 3 | SEC use only | SEC use only | |
| 4 | Source of funds (See Instructions)<br>**OO** | Source of funds (See Instructions)<br>**OO** | |
| 5 | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)<br>[ ] | |
| 6 | Citizenship or place of organization<br>**X1** | Citizenship or place of organization<br>**X1** | |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 7 | Sole Voting Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 8 | Shared Voting Power<br>**4310811.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 9 | Sole Dispositive Power<br>**0.00** |
| Number of Shares<br>Beneficially Owned by<br>Each Reporting Person With: | 10 | Shared Dispositive Power<br>**4310811.00** |
| 11 | Aggregate amount beneficially owned by each reporting person<br>**4310811.00** | Aggregate amount beneficially owned by each reporting person<br>**4310811.00** | |
| 12 | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)<br>[ ] | |
| 13 | Percent of class represented by amount in Row (11)<br>**13.55%** | Percent of class represented by amount in Row (11)<br>**13.55%** | |
| 14 | Type of Reporting Person (See Instructions)<br>**OO** | Type of Reporting Person (See Instructions)<br>**OO** | |

---

**Item 1. Security and Issuer**

**(a) Title of Class of Securities:**
Common Stock, $0.01 par value

**(b) Name of Issuer:**
Mistras Group, Inc.

**(c) Address of Issuer's Principal Executive Offices:**
195 Clarksville Road, Princeton Junction, NJ, 08550

The percentage calculations reflected in Rows (13) above are based on 31,816,681 outstanding shares as of May 7, 2026, as reported by the issuer.

**Item 4. Purpose of Transaction**

The Reporting Persons acquired, and presently beneficially own, shares of the issuer's common stock for investment purposes. None of the Reporting Persons currently has any plans or proposals that would result in or relate to any of the transactions or changes listed in Items 4(a) through 4(j) of Schedule 13D. However, as part of their ongoing evaluation of their investment and investment alternatives, the Reporting Persons may consider such matters and, subject to applicable law, may formulate a plan with respect to such matters or make formal proposals to the board of directors of the issuer, other stockholders of the issuer, or other third parties regarding such matters. The Reporting Persons reserve the right to acquire additional securities of the issuer in the open markets, in privately negotiated transactions (which may be with the issuer or with third parties) or otherwise, to dispose of all or a portion of their holdings of securities of the issuer, or to change their intention with respect to any or all of the matters referred to in this Item 4.

**Item 5. Interest in Securities of the Issuer**

**(a)**
The responses to Rows 11 and 13 in each Reporting Person's cover page, indicating the aggregate number and percentage of shares of the issuer's common stock beneficially owned by each Reporting Person, are incorporated herein by reference. The total number of shares which are beneficially owned by the Reporting Persons is 5,917,135 shares, or approximately 18.60% of the outstanding shares of the issuer's common stock. The ownership percentages were calculated based on 31,816,681 outstanding shares as of May 7, 2026, as reported by the issuer.

**(b)**
The responses of each Reporting Person to Rows 7 through 10 on the cover page of this Schedule 13D are incorporated herein by reference.

**(c)**
The Trust was established on December 31, 2025, and 4,722,686 shares of the issuer held by the Trust  Were acquired by a gift from Ms. Vahaviolos on the same date.

**Item 6. Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer.**

None.

### 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.

**Reporting Person:** Stephanie Foglia

**Signature:** /s/ Stephanie Foglia

**Name/Title:** Stephanie Foglia

**Date:** 06/12/2026

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.

**Reporting Person:** 2025 Irrevocable Two-Year Grantor Retained Annuity Trust of Aspasia F. Vahaviolos

**Signature:** /s/ Stephanie Foglia

**Name/Title:** Stephanie Foglia/Trustee

**Date:** 06/12/2026