MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2014

Feb 14, 2014

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2014-02-11

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

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2014-02-11	Common Stock	M	1291	$15.03	Acquired	95140	Direct
2014-02-11	Common Stock	S	1291	$34.4629	Disposed	93849	Direct
2014-02-11	Common Stock	M	1103	$14.89	Acquired	94952	Direct
2014-02-11	Common Stock	S	1103	$34.4629	Disposed	93849	Direct
2014-02-11	Common Stock	M	2127	$10.41	Acquired	95976	Direct
2014-02-11	Common Stock	S	2127	$34.4629	Disposed	93849	Direct
2014-02-11	Common Stock	M	80	$10.41	Acquired	93929	Direct
2014-02-11	Common Stock	S	80	$34.4629	Disposed	93849	Direct
2014-02-13	Common Stock	M	1882	$17.92	Acquired	95731	Direct
2014-02-13	Common Stock	S	1882	$34.705	Disposed	93849	Direct
2014-02-13	Common Stock	M	2944	$15.03	Acquired	96793	Direct
2014-02-13	Common Stock	S	2944	$34.705	Disposed	93849	Direct
2014-02-13	Common Stock	S	8560	$34.9003	Disposed	85289	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2014-02-11	Non-Qualified Stock Option (right to buy)	$10.41	M	2127	Disposed	2014-12-07	Common Stock (2127)	Direct
2014-02-11	Non-Qualified Stock Option (right to buy)	$10.41	M	80	Disposed	2014-12-07	Common Stock (80)	Direct
2014-02-11	Non-Qualified Stock Option (right to buy)	$14.89	M	1103	Disposed	2015-02-08	Common Stock (1103)	Direct
2014-02-11	Non-Qualified Stock Option (right to buy)	$15.03	M	1291	Disposed	2015-10-28	Common Stock (1291)	Direct
2014-02-13	Non-Qualified Stock Option (right to buy)	$15.03	M	2944	Disposed	2015-10-28	Common Stock (2944)	Direct
2014-02-13	Non-Qualified Stock Option (right to buy)	$17.92	M	1882	Disposed	2014-08-03	Common Stock (1882)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	7655	Indirect

Footnotes

F1: 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 $34.405 to $34.47. 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.

F2: 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 $34.70 to $34.74. 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.

F3: 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 $34.77 to $34.995. 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.