MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2012

Feb 29, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2012-02-29

Reporting Person: CHANG KUO WEI HERBERT (Director)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-02-29	Common Stock	M	15000.0	$16.97	Acquired	106035.0	Direct
2012-02-29	Common Stock	S	15000.0	$18.9852	Disposed	91035.0	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2012-02-29	Non-Qualified Stock Option (right to buy)	$16.97	M	15000.0	Disposed	2014-05-24	Common Stock (15000.0)	Direct

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 $18.691 to $19.20. 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.