MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2012

Nov 5, 2012

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2012-11-01

Reporting Person: Sciammas Maurice (Sr. V.P.of Sales and Marketing)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2012-11-01	Common Stock	S	1287.0	$17.3412	Disposed	117508.0	Direct
2012-11-05	Common Stock	S	1775.0	$19.0341	Disposed	115733.0	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	74004.0	Indirect
Common Stock	16371.0	Indirect
Common Stock	16371.0	Indirect

Footnotes

F1: 50% of the Performance Units are subject to vest on the first anniversay of the Grant Date and 50% of the Performance Units are subject to vest on the second anniversary of the Grant Date, provided that the Grantee continues to be a service provider on such dates.

F2: Shares sold to pay tax obligations resulting from the vesting of restricted stock units.

F3: In accordance with the reporting person's 10b5-1 trading plan.

F4: 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 $18.69 to $19.31. 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.