MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2015

Feb 5, 2015

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2015-02-03

Reporting Person: Tseng Saria (VP & General Counsel)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2015-02-03	Common Stock	A	90181.0	$0.0	Acquired	206346	Direct
2015-02-03	Common Stock	S	1013.0	$47.21	Disposed	205333	Direct
2015-02-03	Common Stock	S	51.0	$47.21	Disposed	205282	Direct
2015-02-03	Common Stock	A	8071.0	$0.0	Acquired	213353	Direct
2015-02-05	Common Stock	S	724.0	$48.0202	Disposed	212629	Direct
2015-02-05	Common Stock	S	6090.0	$47.7955	Disposed	206539	Direct
2015-02-05	Common Stock	S	15127.0	$47.7954	Disposed	191412	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	2000	Indirect

Footnotes

F1: On February 11, 2013, the reporting person was granted a target of 31,930 shares of restricted stock units subject to satisfaction of pre-determined, performance-based vesting criteria. On February 3, 2015, the Company's Board of Directors determined that those performance criteria for the restricted stock units had been satisfied, which resulted in 58,251 additional shares being achieved and granted to the reporting person. Of the restricted stock units that were awarded, 45,090 will vest immediately and 45,091 will vest quarterly in the next two years.

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

F3: 1/12 of the Restricted Stock Units shall vest quarterly following the Vesting Commencement Date, provided that the Grantee continues to be a Service Provider from the Grant Date through each applicable vesting date.