Sec Form 4 Filing - Vahaviolos Sotirios J. @ Mistras Group, Inc. - 2023-01-09

FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

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, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person Vahaviolos Sotirios J. 2. Issuer Name and Ticker or Trading Symbol Mistras Group, Inc. [ MG] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director X __ 10% Owner X __ Officer (give title below) _____ Other (specify below) Executive Chairman (Last) (First) (Middle) C/O MISTRAS GROUP, INC., 195 CLARKSVILLE ROAD 3. Date of Earliest Transaction (MM/DD/YY) 01/09/2023 (Street) PRINCETON JUNCTION, NJ08550 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) __ X __ Form filed by One Reporting Person _____ Form filed by More than One Reporting Person (City) (State) (Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned 1.Title of Security (Instr. 3) 2. Transaction Date (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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 01/09/2023 G V 6,734,718( 1 ) D $ 0 1,872,159 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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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 (MM/DD/YY) 7. Title and Amount of Underlying Securities (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 of Derivative Security: 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

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Vahaviolos Sotirios J. C/O MISTRAS GROUP, INC. 195 CLARKSVILLE ROAD PRINCETON JUNCTION, NJ08550 X X Executive Chairman Signatures Michael C. Keefe, attorney-in-fact for Sotirios J. Vahaviolos 01/18/2023 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Transaction represents a gift by the reporting person to the Sotirios Vahaviolos January 2023 2-Year Grantor Retained Annuity Trust (GRAT). Dr. Vahaviolos has retained an interest in the value of the original principal contribution to the GRAT and will receive annuity payments which may be in shares If the GRAT retains the shares. Any shares retained by the GRAT after annuity payments will be distributed to the beneficiaries of the GRAT upon its termination in two years. Dr. Vahaviolos' daughter, who does not reside with him, is the trustee for the GRAT and will hold sole power over the voting and disposition of the shares held by the GRAT. Dr. Vahaviolos and the GRAT trustee have agreed that the GRAT will be subject to the issuer's insider trading compliance policy regarding the shares held by the GRAT.

Remarks: Dr. Vahaviolos has voluntarily elected to report this transaction on a Form 4 around the time of this gift transaction rather than wait until after the end of the year and report the transaction on a Form 5.

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).

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