MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2011

Aug 25, 2011

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2011-08-25

Reporting Person: Ueunten Paul (Sr. V.P. Design Engineering)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2011-08-15	Common Stock	J	438	$10.6505	Acquired	123767	Direct
2011-08-25	Common Stock	M	13000	$1.2	Acquired	136767	Direct
2011-08-25	Common Stock	S	13000	$12.34	Disposed	123767	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2011-08-25	Incentive Stock Option (right to buy)	$1.2	M	13000	Disposed	2013-09-11	Common Stock (13000)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	153556	Indirect
Common Stock	113900	Indirect
Common Stock	26000	Indirect
Common Stock	26000	Indirect

Footnotes

F1: Acquired through the Company's qualified ESPP program.

F2: In accordance with the reporting person's 10b5-1 trading plan.