Sec Form 4 Filing - SERRANO ELIJIO V @ TETRA TECHNOLOGIES INC - 2024-02-22

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 SERRANO ELIJIO V 2. Issuer Name and Ticker or Trading Symbol TETRA TECHNOLOGIES INC [ TTI] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) Sr. Vice President & CFO (Last) (First) (Middle) 24955 INTERSTATE 45 NORTH 3. Date of Earliest Transaction (MM/DD/YY) 02/22/2024 (Street) THE WOODLANDS, TX77380 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 02/22/2024 M( 1 ) 42,511 A $ 0 1,150,096 D Common Stock 02/22/2024 F( 2 ) 16,340 D $ 3.83 1,133,756 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 Restricted Stock Units $ 0 02/22/2024 M( 1 ) 42,511 ( 3 ) ( 3 ) Common Stock 42,511 $ 0 85,024 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other SERRANO ELIJIO V 24955 INTERSTATE 45 NORTH THE WOODLANDS, TX77380 Sr. Vice President & CFO Signatures Kimberly M. O'Brien, attorney in fact 02/26/2024 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Represents vested shares of restricted stock units granted on February 22, 2023. Restricted stock units convert into common stock on a one-for-one basis. ( 2 )Reflects units surrendered to the Issuer to satisfy tax withholding obligations upon the vesting of the restricted stock unit granted on February 22, 2023. ( 3 )The remaining unvested portion of this restricted stock unit award will vest every six months until fully vested on February 25, 2026. Each restricted stock unit represents the contingent right to receive one share of the Issuer's common stock upon vesting of the unit.

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.
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