MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2025

Nov 13, 2025

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2025-11-12

Reporting Person: Hsing Michael (N/A)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2025-11-12	Common Stock	S	403	$957.58	Disposed	955266	Direct
2025-11-12	Common Stock	S	2799	$958.34	Disposed	952467	Direct
2025-11-12	Common Stock	S	440	$959.36	Disposed	952027	Direct
2025-11-12	Common Stock	S	403	$960.45	Disposed	951624	Direct
2025-11-12	Common Stock	S	1904	$961.63	Disposed	949720	Direct
2025-11-12	Common Stock	S	2817	$962.61	Disposed	946903	Direct
2025-11-12	Common Stock	S	3552	$963.47	Disposed	943351	Direct
2025-11-12	Common Stock	S	3264	$964.47	Disposed	940087	Direct
2025-11-12	Common Stock	S	5619	$965.50	Disposed	934468	Direct
2025-11-12	Common Stock	S	6562	$966.45	Disposed	927906	Direct
2025-11-12	Common Stock	S	3024	$967.41	Disposed	924882	Direct
2025-11-12	Common Stock	S	2072	$968.37	Disposed	922810	Direct
2025-11-12	Common Stock	S	975	$969.62	Disposed	921835	Direct
2025-11-12	Common Stock	S	728	$970.29	Disposed	921107	Direct
2025-11-12	Common Stock	S	59	$971.81	Disposed	921048	Direct
2025-11-12	Common Stock	S	461	$972.78	Disposed	920587	Direct
2025-11-12	Common Stock	S	298	$973.73	Disposed	920289	Direct
2025-11-12	Common Stock	S	633	$979.59	Disposed	919656	Direct
2025-11-12	Common Stock	S	987	$980.06	Disposed	918669	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	133040	Indirect
Common Stock	12825	Indirect

Footnotes

F1: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $957.18 to $957.95. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F2: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $958.06 to $958.88. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F3: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $959.01 to $959.56. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F4: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $960.00 to $960.74. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F5: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $961.07 to $961.98. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F6: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $962.02 to $962.99. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F7: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $963.00 to $963.99. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F8: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $964.00 to $964.92. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F9: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $965.00 to $965.98. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F10: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $966.00 to $ 966.99. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F11: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $967.00 to $967.93. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F12: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $968.01 to $968.94. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F13: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $969.14 to $969.98. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F14: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $970.02 to $970.85. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F15: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $971.74 to $971.96. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F16: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $972.05 to $972.98. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F17: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $973.45 to $973.84. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F18: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $979.59 to $979.60. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.

F19: The price is the weighted average sale price for the transactions reported on this line. The prices for the transactions reported on this line range from $980.00 to $980.25. The reporting person undertakes to provide, upon request by the staff of the Securities and Exchange Commission, the issuer, or a security holder of the issuer, full information regarding the number of shares sold at each separate price.