Schedule 13G
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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

 

 

SCHEDULE 13G

 

 

Under the Securities Exchange Act of 1934

 

 

 

Monolithic Power Systems, Inc.


(Name of Issuer)

 

Common Stock


(Title of Class of Securities)

 

 

609839 10 5


                                (CUSIP Number)                                

 

December 31, 2005


(Date of Event Which Requires Filing of this Statement)

 

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

 

¨ Rule 13d-1(b)

 

¨ Rule 13d-1(c)

 

x Rule 13d-1(d)

 

*   The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

 

The information required in the remainder of this cover page shall not be deemed to be ‘‘filed’’ for the purpose of Section 18 of the Securities Exchange Act of 1934 (‘‘Act’’) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

 

Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

 

SEC 1745 (12-02)


CUSIP No. 609839 10 5        

 

  1.  

Names of Reporting Persons.

I.R.S. Identification Nos. of above persons (entities only).

 

            Chang, Kuo Wei Herbert

   
  2.  

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ¨

(b)  x

   
  3.  

SEC Use Only

 

   
  4.  

Citizenship or Place of Organization

 

            Taiwan, ROC

   

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With:

 

  5.    Sole Voting Power

 

                80,000(1)


  6.    Shared Voting Power

 

                4,091,953(2)(3)


  7.    Sole Dispositive Power

 

                80,000(1)


  8.    Shared Dispositive Power

 

                4,091,953(2)(3)

  9.  

Aggregate Amount Beneficially Owned by Each Reporting Person

 

            4,171,953(1)(2)(3)

   
10.  

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

 

 

¨

 

11.  

Percent of Class Represented by Amount in Row (9)

 

            14.41%

   
12.  

Type of Reporting Person (See Instructions)

 

            IN

   

 

Page 2 of 15 pages


CUSIP No. 609839 10 5        

 

  1.  

Names of Reporting Persons.

I.R.S. Identification Nos. of above persons (entities only).

 

            InveStar Capital, Inc.

   
  2.  

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ¨

(b)  x

   
  3.  

SEC Use Only

 

   
  4.  

Citizenship or Place of Organization

 

            Cayman Islands

   

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With:

 

  5.    Sole Voting Power

 


  6.    Shared Voting Power

 

                3,960,998(2)


  7.    Sole Dispositive Power

 


  8.    Shared Dispositive Power

 

                3,960,998(2)

  9.  

Aggregate Amount Beneficially Owned by Each Reporting Person

 

            3,960,998(2)

   
10.  

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

 

 

¨

 

11.  

Percent of Class Represented by Amount in Row (9)

 

            13.68%

   
12.  

Type of Reporting Person (See Instructions)

 

            CO

   

 

Page 3 of 15 pages


CUSIP No. 609839 10 5        

 

  1.  

Names of Reporting Persons.

I.R.S. Identification Nos. of above persons (entities only).

 

            InveStar Semiconductor Development Fund, Inc.

   
  2.  

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ¨

(b)  x

   
  3.  

SEC Use Only

 

   
  4.  

Citizenship or Place of Organization

 

            Cayman Islands

   

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With:

 

  5.    Sole Voting Power

 


  6.    Shared Voting Power

 

                1,974,690


  7.    Sole Dispositive Power

 


  8.    Shared Dispositive Power

 

                1,974,690

  9.  

Aggregate Amount Beneficially Owned by Each Reporting Person

 

            1,974,690

   
10.  

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

 

 

¨

 

11.  

Percent of Class Represented by Amount in Row (9)

 

            6.82%

   
12.  

Type of Reporting Person (See Instructions)

 

            CO

   

 

Page 4 of 15 pages


CUSIP No. 609839 10 5        

 

  1.  

Names of Reporting Persons.

I.R.S. Identification Nos. of above persons (entities only).

 

            InveStar Semiconductor Development Fund, Inc. (II) LDC

   
  2.  

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ¨

(b)  x

   
  3.  

SEC Use Only

 

   
  4.  

Citizenship or Place of Organization

 

            Cayman Islands

   

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With:

 

  5.    Sole Voting Power

 


  6.    Shared Voting Power

 

                864,489


  7.    Sole Dispositive Power

 


  8.    Shared Dispositive Power

 

                864,489

  9.  

Aggregate Amount Beneficially Owned by Each Reporting Person

 

            864,489

   
10.  

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

 

 

¨

 

11.  

Percent of Class Represented by Amount in Row (9)

 

            2.99%

   
12.  

Type of Reporting Person (See Instructions)

 

            CO

   

 

Page 5 of 15 pages


CUSIP No. 609839 10 5        

 

  1.  

Names of Reporting Persons.

I.R.S. Identification Nos. of above persons (entities only).

 

            InveStar Burgeon Venture Capital, Inc.

   
  2.  

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ¨

(b)  x

   
  3.  

SEC Use Only

 

   
  4.  

Citizenship or Place of Organization

 

            Cayman Islands

   

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With:

 

  5.    Sole Voting Power

 


  6.    Shared Voting Power

 

                677,671


  7.    Sole Dispositive Power

 


  8.    Shared Dispositive Power

 

                677,671

  9.  

Aggregate Amount Beneficially Owned by Each Reporting Person

 

            677,671

   
10.  

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

 

 

¨

 

11.  

Percent of Class Represented by Amount in Row (9)

 

            2.34%

   
12.  

Type of Reporting Person (See Instructions)

 

            CO

   

 

Page 6 of 15 pages


CUSIP No. 609839 10 5        

 

  1.  

Names of Reporting Persons.

I.R.S. Identification Nos. of above persons (entities only).

 

            InveStar Excelsus Venture Capital (International) Inc., LDC

   
  2.  

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ¨

(b)  x

   
  3.  

SEC Use Only

 

   
  4.  

Citizenship or Place of Organization

 

            Cayman Islands

   

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With:

 

  5.    Sole Voting Power

 


  6.    Shared Voting Power

 

                313,193


  7.    Sole Dispositive Power

 


  8.    Shared Dispositive Power

 

                313,193

  9.  

Aggregate Amount Beneficially Owned by Each Reporting Person

 

            313,193

   
10.  

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

 

 

¨

 

11.  

Percent of Class Represented by Amount in Row (9)

 

            1.08%

   
12.  

Type of Reporting Person (See Instructions)

 

            CO

   

 

Page 7 of 15 pages


CUSIP No. 609839 10 5        

 

  1.  

Names of Reporting Persons.

I.R.S. Identification Nos. of above persons (entities only).

 

            InveStar Dayspring Venture Capital, Inc.

   
  2.  

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ¨

(b)  x

   
  3.  

SEC Use Only

 

   
  4.  

Citizenship or Place of Organization

 

            Taiwan, ROC

   

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With:

 

  5.    Sole Voting Power

 


  6.    Shared Voting Power

 

                130,955


  7.    Sole Dispositive Power

 


  8.    Shared Dispositive Power

 

                130,955

  9.  

Aggregate Amount Beneficially Owned by Each Reporting Person

 

            130,955

   
10.  

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

 

 

¨

 

11.  

Percent of Class Represented by Amount in Row (9)

 

            0.45%

   
12.  

Type of Reporting Person (See Instructions)

 

            CO

   

 

Page 8 of 15 pages


CUSIP No. 609839 10 5        

 

  1.  

Names of Reporting Persons.

I.R.S. Identification Nos. of above persons (entities only).

 

            Kenneth Tai

   
  2.  

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ¨

(b)  x

   
  3.  

SEC Use Only

 

   
  4.  

Citizenship or Place of Organization

 

            Taiwan, ROC

   

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With:

 

  5.    Sole Voting Power

 


  6.    Shared Voting Power

 

                130,955(3)


  7.    Sole Dispositive Power

 


  8.    Shared Dispositive Power

 

                130,955(3)

  9.  

Aggregate Amount Beneficially Owned by Each Reporting Person

 

            130,955(3)

   
10.  

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

 

 

¨

 

11.  

Percent of Class Represented by Amount in Row (9)

 

            0.45%

   
12.  

Type of Reporting Person (See Instructions)

 

            IN

   

 

Page 9 of 15 pages


CUSIP No. 609839 10 5        

 

  1.  

Names of Reporting Persons.

I.R.S. Identification Nos. of above persons (entities only).

 

            Forefront Associates LLC

   
  2.  

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ¨

(b)  x

   
  3.  

SEC Use Only

 

   
  4.  

Citizenship or Place of Organization

 

            Delaware

   

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With:

 

  5.    Sole Voting Power

 


  6.    Shared Voting Power

 

                130,955(3)


  7.    Sole Dispositive Power

 


  8.    Shared Dispositive Power

 

                130,955(3)

  9.  

Aggregate Amount Beneficially Owned by Each Reporting Person

 

            130,955(3)

   
10.  

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

 

 

¨

 

11.  

Percent of Class Represented by Amount in Row (9)

 

            0.45%

   
12.  

Type of Reporting Person (See Instructions)

 

            OO

   

 

Page 10 of 15 pages


CUSIP No. 609839 10 5        

 

  1.  

Names of Reporting Persons.

I.R.S. Identification Nos. of above persons (entities only).

 

            Forefront Venture Partners, L.P.

   
  2.  

Check the Appropriate Box if a Member of a Group (See Instructions)

(a)  ¨

(b)  x

   
  3.  

SEC Use Only

 

   
  4.  

Citizenship or Place of Organization

 

            Delaware

   

Number of

Shares

Beneficially

Owned by

Each

Reporting

Person

With:

 

  5.    Sole Voting Power

 


  6.    Shared Voting Power

 

                130,955


  7.    Sole Dispositive Power

 


  8.    Shared Dispositive Power

 

                130,955

  9.  

Aggregate Amount Beneficially Owned by Each Reporting Person

 

            130,955

   
10.  

Check if the Aggregate Amount in Row (9) Excludes Certain Shares (See Instructions)

 

 

¨

 

11.  

Percent of Class Represented by Amount in Row (9)

 

            0.45%

   
12.  

Type of Reporting Person (See Instructions)

 

            PN

   

 

Page 11 of 15 pages


Item 1.

 

(a)

  

Name of Issuer

 

Monolithic Power Systems, Inc.

         
   

(b)

  

Address of Issuer’s Principal Executive Offices

 

983 University Avenue, Building A, Los Gatos, CA 95032

         

Item 2.

 

(a)-(c)

  

This Statement is Filed by:

 

Kuo Wei Herbert Chang (“Chang”); Forefront Venture Partners LP and Forefront Associates LLC (collectively, “Forefront”); InveStar Burgeon Venture Capital, Inc., InveStar Dayspring Venture Capital, Inc., InveStar Semiconductor Development Fund, Inc. (II) LDC, InveStar Excelsus Venture Capital (International) Inc., LDC and InveStar Semiconductor Development Fund, Inc. and InveStar Capital, Inc. (collectively, “InveStar”); and Kenneth Tai (“Tai”).

 

The Business Address of Forefront is 375 W. Trimble Road, San Jose, CA 95131. The Business Address of Chang, InveStar and Tai is Room 1201, 333. Keelung Road, Section 1, Taipei, Taiwan, R.O.C.

 

Chang and Tai are citizens of Taiwan, ROC; Forefront Venture Partners LP is a Delaware limited partnership; Forefront Associates LLC is a Delaware limited liability company; InveStar Dayspring Venture Capital, Inc. is a Taiwan, ROC corporation; InveStar Capital, Inc., InveStar Semiconductor Development Fund, Inc. (II) LDC, InveStar Burgeon Venture Capital, Inc., InveStar Excelus Venture Capital (International), Inc., LDC, and InveStar Semiconductor Development Fund, Inc. are Cayman Island corporations.

 

Chang, Forefront, InveStar and Tai are individually referred to herein as “Reporting Person” and collectively, as the “Reporting Persons.”

         
   

(d)

  

Title of Class of Securities

 

Common Stock

         
   

(e)

  

CUSIP Number

 

609839 10 5

         

Item 3.

  N/A     

 

Page 12 of 15 pages


Item 4.

   Ownership.          
     Provide the following information regarding the aggregate number and percentage of the class of securities of the issuer identified in Item 1.          
     (a)   

Amount beneficially owned:

 

See Row 9 for the amount beneficially owned by each Reporting Person.

         
     (b)   

Percent of class:

 

See Row 11 for the percentage of class beneficially owned by each Reporting Person.

         
     (c)   

Number of shares as to which the person has:

 

See Rows 5-8 for the voting and dispositive power for each Reporting Person.

         

Item 5.

  

Ownership of Five Percent or Less of a Class

 

N/A

    

Item 6.

  

Ownership of More than Five Percent on Behalf of Another Person.

 

N/A

         

Item 7.

  

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on by the Parent Holding Company

 

N/A

Item 8.

  

Identification and Classification of Members of the Group

 

The Reporting Persons may be deemed to be a “group” for the purposes of Section 13(g) of the Act and the rules thereunder, although each expressly disclaims any assertion or presumption that it or the other person on whose behalf this statement is filed constitute a “group.” The filing of this statement should not be construed to be an admission that any of the Reporting Persons is a member of a “group” consisting of one or more of such persons. A copy of the Agreement Relating to Joint Filing of Schedule 13(G) is attached hereto as Exhibit A.

         

Item 9.

  

Notice of Dissolution of Group

 

N/A

         

Item 10.

  

Certification

 

N/A

 

(1)      Includes options to purchase 80,000 shares of common stock that are exercisable within 60 days of December 31, 2005.

(2)      Includes (i) 1,974,690 shares of common stock held of record by InveStar Semiconductor Development Fund, Inc.; (ii) 864,489 shares of common stock held of record by InveStar Semiconductor Development Fund, Inc. (II) LDC; (iii) 677,671 shares of common stock held of record by InveStar Burgeon Venture Capital, Inc.; (iv) 313,193 shares of common stock held of record by InveStar Excelsus Venture Capital (International) Inc., LDC; and (v) 130,955 shares of common stock held of record by InveStar Dayspring Venture Capital, Inc.

(3)      Includes 130,955 shares of common stock held of record by Forefront Venture Partners, L.P.

         

 

Page 13 of 15 pages


SIGNATURE

 

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

 

February 14, 2006

 

/s/ Kuo Wei Herbert Chang


Kuo Wei Herbert Chang, individually, and on behalf of;
InveStar Capital, Inc., as President;
InveStar Semiconductor Development Fund, Inc., as Secretary and as President of InveStar Capital, Inc., the management company of InveStar Semiconductor Development Fund, Inc.;
InveStar Semiconductor Development Fund, Inc. (II) LDC, as Secretary and as President of InveStar Capital, Inc., the management company of InveStar Semiconductor Development Fund, Inc. (II) LDC;
InveStar Excelsus Venture Capital (International) Inc., LDC, as Secretary and as President of InveStar Capital, Inc., the management company of InveStar Excelsus Venture Capital (International) Inc., LDC;
InveStar Burgeon Venture Capital, Inc., as Secretary and as President of InveStar Capital, Inc., the management company of InveStar Burgeon Venture Capital, Inc.;
InveStar Dayspring Venture Capital, Inc., as Secretary and as President of InveStar Capital, Inc., the management company of InveStar Dayspring Venture Capital, Inc.;
Forefront Associates LLC, as managing member; and
Forefront Venture Partners, L.P., as managing member of its general partner Forefront Associates LLC;

/s/ Kenneth Tai


Kenneth Tai

 

The original statement shall be signed by each person on whose behalf the statement is filed or his authorized representative. If the statement is signed on behalf of a person by his authorized representative other than an executive officer or general partner of the filing person, evidence of the representative’s authority to sign on behalf of such person shall be filed with the statement, provided, however, that a power of attorney for this purpose which is already on file with the Commission may be incorporated by reference. The name and any title of each person who signs the statement shall be typed or printed beneath his signature.

 

NOTE: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties for whom copies are to be sent.

 

Attention: Intentional misstatements or omissions of fact constitute Federal criminal violations (See 18 U.S.C. 1001)

 

Page 14 of 15 pages


EXHIBIT A

 

AGREEMENT RELATING TO JOINT FILING OF SCHEDULE 13G

 

The undersigned hereby agree that a single Schedule 13G (or any amendment thereto) relating to the Common Stock of Monolithic Power Systems, Inc. shall be filed on behalf of each of the undersigned and that this Agreement shall be filed as an Exhibit to such Schedule 13G.

 

This Agreement and the filing of the Schedule 13G shall not be construed to be an admission that any of the undersigned is a member of a “group” consisting of one or more of such persons pursuant to Section 13(g) of the Securities Exchange Act of 1934, as amended and the rules thereunder.

 

Dated: February 14, 2006

 

/s/ Kuo Wei Herbert Chang


Kuo Wei Herbert Chang, individually, and on behalf of;
InveStar Capital, Inc., as President;
InveStar Semiconductor Development Fund, Inc., as Secretary and as President of InveStar Capital, Inc., the management company of InveStar Semiconductor Development Fund, Inc.;
InveStar Semiconductor Development Fund, Inc. (II) LDC, as Secretary and as President of InveStar Capital, Inc., the management company of InveStar Semiconductor Development Fund, Inc. (II) LDC;
InveStar Excelsus Venture Capital (International) Inc., LDC, as Secretary and as President of InveStar Capital, Inc., the management company of InveStar Excelsus Venture Capital (International) Inc., LDC;
InveStar Burgeon Venture Capital, Inc., as Secretary and as President of InveStar Capital, Inc., the management company of InveStar Burgeon Venture Capital, Inc.;
InveStar Dayspring Venture Capital, Inc., as Secretary and as President of InveStar Capital, Inc., the management company of InveStar Dayspring Venture Capital, Inc.;
Forefront Associates LLC, as managing member; and
Forefront Venture Partners, L.P., as managing member of its general partner Forefront Associates LLC;

/s/ Kenneth Tai


Kenneth Tai

 

Page 15 of 15 pages