MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2013

May 6, 2013

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2013-05-02

Reporting Person: Rao Meera (CFO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2013-05-02	Common Stock	S	1398.0	$23.1711	Disposed	93667	Direct
2013-05-02	Common Stock	A	173.0	$0.0	Acquired	93840	Direct
2013-05-02	Common Stock	S	67.0	$23.17	Disposed	93773	Direct
2013-05-03	Common Stock	S	72.0	$24.18	Disposed	93701	Direct
2013-05-03	Common Stock	A	9.0	$0.0	Acquired	93710	Direct

Footnotes

F1: Shares sold to pay tax obligations resulting from the vesting of restricted stock units.

F2: Equitable stock dividend adjustment approved by the Board of Director as a result of dividend Payment to shareholders on December 28, 2012. Stock dividends will release according to the same vesting schedule as the original grants.