Sec Form 4 Filing - Kelley Stephen Douglas @ ADVANCED ENERGY INDUSTRIES INC - 2025-03-01

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 Kelley Stephen Douglas 2. Issuer Name and Ticker or Trading Symbol ADVANCED ENERGY INDUSTRIES INC [ AEIS] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) X __ Director _____ 10% Owner X __ Officer (give title below) _____ Other (specify below) President and CEO (Last) (First) (Middle) 1595 WYNKOOP STREET, SUITE 800 3. Date of Earliest Transaction (MM/DD/YY) 03/01/2025 (Street) DENVER, CO80202 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 03/01/2025 M 10,450 A 107,186 D Common Stock 03/01/2025 F 9,361 ( 2 ) D $ 115.17 97,825 ( 3 ) 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 ( 1 ) 03/01/2025 M 10,450 ( 1 ) ( 1 ) Common Stock 10,450 $ 0 20,898 D Restricted Stock Units $ 0 03/01/2025 A 27,388 ( 4 ) ( 4 ) Common Stock 27,388 $ 0 27,388 D Performance Units $ 0 03/01/2025 A V 42,135 ( 5 ) ( 5 ) Common Stock 42,135 $ 0 42,135 D

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other Kelley Stephen Douglas 1595 WYNKOOP STREET, SUITE 800 DENVER, CO80202 X President and CEO Signatures /s/ Elizabeth Vonne - Attorney-in-Fact 03/04/2025 Signature of Reporting Person Date

Explanation of Responses:

( 1 )On March 1, 2024, the reporting person was granted 31,348 restricted stock units ("RSUs") vesting in three equal installments beginning on the first anniversary of the grant date, of which the first installment vested on March 1, 2025. RSUs convert into common stock on a one-for-one basis. ( 2 )Payment of tax liability by withholding securities incident to vesting of RSUs. ( 3 )Represents 30,753 shares of unvested restricted stock units and 67,072 shares of common stock. ( 4 )These employee RSUs were issued pursuant to the Company's Amended and Restated 2023 Omnibus Incentive Plan ("LTI Plan") and will vest in three equal installments beginning on the first anniversary of the grant date. ( 5 )These performance share awards were issued pursuant to the LTI Plan at 100% of target, have a three-year performance period, and will vest in all or in part upon achievement of performance metrics. Any awards that have not been vested and released at the end of the three-year performance period will be canceled.

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).

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