MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2011

Mar 9, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2011-03-08

Reporting Person: Moyer James C (Director, Chief IC Design Engineer)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-03-08	Common Stock	M	12000	$7.77	Acquired	907896	Direct
2011-03-08	Common Stock	M	99999	$5	Acquired	1007895	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-03-08	Incentive Stock Option (right to buy)	$7.77	M	12000	Disposed	2015-01-26	Common Stock (12000)	Direct
2011-03-08	Non-Qualified Stock Option (right to buy)	$5	M	99999	Disposed	2014-01-13	Common Stock (99999)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	483383	Indirect

Footnotes

F1: Represents vested shares acquired through the cash exercise of a stock option in compliance with the Company's Insider Trading Compliance Program.