MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2013

Feb 8, 2013

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2013-02-06

Reporting Person: Rao Meera (CFO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2013-02-06	Common Stock	S	3575.0	$22.8888	Disposed	86972.0	Direct
2013-02-06	Common Stock	A	624.0	$0.0	Acquired	87596.0	Direct
2013-02-07	Common Stock	S	248.0	$23.7	Disposed	87348.0	Direct
2013-02-07	Common Stock	M	16000.0	$13.53	Acquired	103348.0	Direct
2013-02-07	Common Stock	S	16000.0	$24.2964	Disposed	87348.0	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2013-02-07	Non-Qualified Stock Option (right to buy)	$13.53	M	16000.0	Disposed	2016-01-05	Common Stock (16000.0)	Direct

Footnotes

F1: Shares sold to pay tax obligations resulting from the vesting of performance units (restricted stock units) originally granted on February 25, 2010. The Performance was met and the shares were released per board approval on February 5, 2013.

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.

F3: Shares sold to pay tax obligations resulting from the release of restricted stock units.

F4: In accordance with the reporting person's 10b5-1 trading plan.

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 $24.00 to $24.73. 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.