Edgar Filing: MONOLITHIC POWER SYSTEMS INC

Ownership Submission

FORM 4

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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3235-0287

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(Print or Type Responses)

1. Name and Address of Reporting Person ^*

Sciammas Maurice

2. Issuer Name and Ticker or Trading Symbol
MONOLITHIC POWER SYSTEMS INC [MPWR]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

_____ Director	_____ 10% Owner
__X__ Officer (give title below)	_____ Other (specify below)
VP, Sales and Marketing

(Last)

(First)

(Middle)

6409 GUADALUPE MINES ROAD

3. Date of Earliest Transaction (Month/Day/Year)
05/16/2008

(Street)

SAN JOSE, CA 95120

4. If Amendment, Date Original Filed(Month/Day/Year)

6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person

(City)

(State)

(Zip)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
1.Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	05/16/2008		S		500	D	$ 24.9	25,717	D
Common Stock	05/16/2008		S		26	D	$ 24.91	25,691	D
Common Stock	05/16/2008		S		2,400	D	$ 24.92	23,291	D
Common Stock	05/16/2008		S		560	D	$ 24.93	22,731	D
Common Stock	05/16/2008		S		200	D	$ 24.94	22,531	D
Common Stock	05/16/2008		S		814	D	$ 24.95	21,717	D
Common Stock	05/16/2008		S		600	D	$ 24.96	21,117	D
Common Stock	05/16/2008		S		868	D	$ 24.97	20,249	D
Common Stock	05/16/2008		S		961	D	$ 24.98	19,288	D
Common Stock	05/16/2008		S		3,000	D	$ 24.99	16,288	D
Common Stock	05/16/2008		S		3,479	D	$ 25	12,809	D
Common Stock	05/16/2008		S		2,200	D	$ 25.01	10,609	D
Common Stock	05/16/2008		S		2,300	D	$ 25.02	8,309	D
Common Stock	05/16/2008		S		1,400	D	$ 25.03	6,909	D
Common Stock	05/16/2008		S		592	D	$ 25.04	6,317	D
Common Stock	05/16/2008		S		100	D	$ 25.05	6,217	D
Common Stock								219,482	I	by Family Trust ⁽¹⁾
Common Stock								42,647	I	byC Sciammas 04 TRST ⁽²⁾
Common Stock								42,647	I	byM Sciammas 04 Trst ⁽³⁾

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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security
(Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code
(Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date
(Month/Day/Year)

7. Title and Amount of Underlying Securities
(Instr. 3 and 4)

8. Price of Derivative Security
(Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)

11. Nature of Indirect Beneficial Ownership
(Instr. 4)

Code

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
Reporting Owner Name / Address	Director	10% Owner	Officer	Other
Sciammas Maurice 6409 GUADALUPE MINES ROAD SAN JOSE, CA 95120			VP, Sales and Marketing

Signatures

By: Adriana Chiocchi For: Maurice Sciammas		05/19/2008
^**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Shares held by Sciammas Family Living Trust, Maurice Sciammas and Christina Sciammas, Trustees
(2)	Shares held by Christina Sciammas 2004 Trust, Christina Sciammas and Maurice Sciammas, Trustees
(3)	Shares held by Maurice Sciammas 2004 Trust, Maurice Sciammas and Christina Sciammas, Trustees

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