MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2013

Aug 9, 2013

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2013-08-07

Reporting Person: Xiao Deming (Pres. of MPS Asia Operations)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2013-08-07	Common Stock	M	40000.0	$17.92	Acquired	121065	Direct
2013-08-07	Common Stock	S	40000.0	$27.0	Disposed	81065	Direct
2013-08-08	Common Stock	A	192.0	$0.0	Acquired	81257	Direct
2013-08-08	Common Stock	S	102.0	$28.28	Disposed	81155	Direct
2013-08-08	Common Stock	S	2167.0	$28.283	Disposed	78988	Direct
2013-08-09	Common Stock	M	1429.0	$15.03	Acquired	13214	Indirect
2013-08-09	Common Stock	M	941.0	$17.92	Acquired	14155	Indirect
2013-08-09	Common Stock	M	141.0	$14.89	Acquired	14296	Indirect
2013-08-09	Common Stock	M	470.0	$15.03	Acquired	14766	Indirect
2013-08-09	Common Stock	S	1429.0	$28.31	Disposed	13337	Indirect
2013-08-09	Common Stock	S	941.0	$28.31	Disposed	12396	Indirect
2013-08-09	Common Stock	S	141.0	$28.31	Disposed	12255	Indirect
2013-08-09	Common Stock	S	470.0	$28.31	Disposed	11785	Indirect
2013-08-09	Common Stock	S	3628.0	$28.31	Disposed	8157	Indirect

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2013-08-07	Non-Qualified Stock Option (right to buy)	$18.77	M	40000.0	Disposed	2014-08-03	Common Stock (40000)	Direct
2013-08-09	Non-Qualified Stock Option (right to buy)	$14.89	M	141.0	Disposed	2015-10-28	Common Stock (141)	Indirect
2013-08-09	Non-Qualified Stock Option (right to buy)	$15.03	M	470.0	Disposed	2015-10-28	Common Stock (470)	Indirect
2013-08-08	Non-Qualified Stock Option (right to buy)	$15.74	M	1429.0	Disposed	2015-10-28	Common Stock (0)	Indirect
2013-08-09	Non-Qualified Stock Option (right to buy)	$17.92	M	941.0	Disposed	2014-08-03	Common Stock (941)	Indirect

Footnotes

F1: In accordance with the reporting person's 10b5-1 trading plan.

F2: On December 11, 2012, the Company's Board declared a special cash dividend of $1.00 per common share, which was paid on December 28, 2012 to all shareholders of record as of the close of business on December 21, 2012. The Board approved a modification whereby each outstanding option as of December 28, 2012 was increased by a ratio of 1.0471 with a corresponding reduction in the exercise price.

F3: 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.

F4: Shares sold to pay tax obligations resulting from the vesting of restricted stock units.