MONOLITHIC POWER SYSTEMS INC — Director's Dealing 2013

Oct 31, 2013

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MONOLITHIC POWER SYSTEMS INC (MPWR)
CIK: 0001280452
Period of Report: 2013-10-29

Reporting Person: Hsing Michael (Director, CEO)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2013-10-29	Common Stock	S	50000.0	$32.0084	Disposed	507344	Direct
2013-10-30	Common Stock	S	100000.0	$31.4619	Disposed	407344	Direct
2013-10-30	Common Stock	M	125000.0	$12.4	Acquired	532344	Direct
2013-10-30	Common Stock	M	5882.0	$12.4	Acquired	538226	Direct
2013-10-30	Common Stock	S	130882.0	$31.3591	Disposed	407344	Direct
2013-10-31	Common Stock	S	72007.0	$31.759	Disposed	335337	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2013-10-30	Non-Qualified Stock Option (right to buy)	$12.4	M	5882.0	Disposed	2015-02-27	Common Stock (5882)	Direct
2013-10-30	Non-Qualified Stock Option (right to buy)	$12.99	M	125000.0	Disposed	2014-02-27	Common Stock (125000)	Direct

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	465566	Indirect
Common Stock	133040	Indirect
Common Stock	29000	Indirect
Common Stock	133040	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 $31.8708 to $32.1618. 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 $31.00 to $32.2211. 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: 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.

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 $31.00 to $31.89. 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.

F5: 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 $31.6096 to $32.05. 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.