MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2017

Feb 8, 2017

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2017-02-06

Reporting Person: Hsing Michael (Director, CEO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2017-02-06	Common Stock	S	19482	$88.2535	Disposed	1142406	Direct
2017-02-07	Common Stock	A	225944	$0.0	Acquired	1368350	Direct
2017-02-07	Common Stock	M	8939	$0.0	Acquired	1377289	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2017-02-07	Performance Shares	$	M	8939	Disposed		Common Stock (8939)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	133040	Indirect

Footnotes

F1: The reported sales were to cover taxes upon the vesting of restricted stock units, as required by the Company's equity incentive plans.

F2: On February 3, 2015, the reporting person was granted a target of 79,745 shares of restricted stock units subject to satisfaction of pre-determined, performance-based vesting criteria. On February 7, 2017, the Company's Board of Directors determined that those performance criteria for the restricted stock units had been satisfied, which resulted in 146,199 additional shares being achieved and granted to the reporting person. Of the restricted stock units that were awarded, 112,972 will vest immediately and 112,972 will vest quarterly in the next two years.

F3: On December 31, 2015, the reporting person was granted a target of 138,743 shares of restricted stock units in four tranches subject to satisfaction of share price targets over the next four years. The vesting of restricted stock units in the second, third and fourth tranches is also subject to the satisfaction of certain operational goals, as determined by the Compensation Committee of the Company. All restricted stock units are subject to time based vesting. Once vested, one-third of shares have no sales restrictions and are sellable on January 1, 2020, one-third of the shares have sales restrictions until January 1, 2021 and one-third of the shares have sales restrictions until January 1, 2022.On October 28, 2016, the Compensation Committee of the Company determined that one of the five share price targets for the first tranche of restricted stock units had been satisfied, which resulted in 8,939 shares being granted, subject to time based vesting described above.