Initial Statement of Beneficial Ownership (Form 3)

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * Balow Frank Anthony III 2. Date of Event Requiring Statement (Month/Day/Year) 10/27/2026 3. Issuer Name and Ticker or Trading Symbol MONOLITHIC POWER SYSTEMS, INC. [MPWR] (Last) (First) (Middle) 1555 PALM BEACH LAKES BLVD. 4. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) Chief Financial Officer 5. If Amendment, Date Original Filed (Month/Day/Year) (Street) WEST PALM BEACH, FL 33401 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 Beneficially Owned

1.Title of Security (Instr. 4) 2. Amount of Securities Beneficially Owned (Instr. 4) 3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5) 4. Nature of Indirect Beneficial Ownership (Instr. 5) Common Stock 2,941(1) D

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.			SEC 1473 (7-02)
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Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
Balow Frank Anthony III 1555 PALM BEACH LAKES BLVD. WEST PALM BEACH, FL 33401			Chief Financial Officer

Signatures

/s/ Saria Tseng, attorney-in-fact for Mr. Frank Anthony Balow III		10/29/2026
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 5(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).
(1)	Includes an aggregate of 1,206 shares of restricted stock units that vest, subject to continued employment, as follows: 104 shares on 11/22/2026; 121 shares on 1/1/2027; 104 shares on 2/22/2027; 121 shares on 4/1/2027; 102 shares on 5/22/2027; 121 shares on 7/1/2027; 106 shares on 8/22/2027; 121 shares on 10/1/2027; 102 shares on 11/22/2027; 106 shares on 2/22/2028; 16 shares on 5/22/2028; 18 shares on 8/22/2028; 16 shares on 11/22/2028; 18 shares on 2/22/2029; 7 shares on 5/22/2029; 8 shares on 8/22/2029; 7 shares on 11/22/2029; 8 shares on 2/22/2030.

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