Sec Form 4 Filing - SCGF III MANAGEMENT LLC @ ALPHA & OMEGA SEMICONDUCTOR Ltd - 2012-09-11

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 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

OMB APPROVAL OMB Number: 3235-0287 Expires: November 30, 2011 Estimated average burden hours per response... 0.5

1. Name and Address of Reporting Person SCGF III MANAGEMENT LLC 2. Issuer Name and Ticker or Trading Symbol ALPHA & OMEGA SEMICONDUCTOR Ltd [ AOSL] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) _____ Director X __ 10% Owner _____ Officer (give title below) _____ Other (specify below) (Last) (First) (Middle) 3000 SAND HILL ROAD, 4-250 3. Date of Earliest Transaction (MM/DD/YY) 09/11/2012 (Street) MENLO PARK, CA94025 4. If Amendment, Date Original Filed (MM/DD/YY) 6. Individual or Joint/Group Filing (Check Applicable Line) _____ Form filed by One Reporting Person __ X __ 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 (MM/DD/YY) 2A. Deemed Execution Date, if any (MM/DD/YY) 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) Code V Amount (A) or (D) Price Common Shares 09/11/2012 S 47,055 D $ 9.45 2,607,165 I By Sequoia Capital Growth Fund III AIV, LP ( 1 ) Common Shares 09/11/2012 S 2,430 D $ 9.45 134,617 I By Sequoia Capital Growth III Principals Fund LLC ( 2 ) Common Shares 09/11/2012 S 515 D $ 9.45 28,554 I By Sequoia Capital Growth Partners III, LP ( 3 ) Common Shares 09/12/2012 S 47,055 D $ 9.45 2,560,110 I By Sequoia Capital Growth Fund III AIV, LP ( 1 ) Common Shares 09/12/2012 S 2,430 D $ 9.45 132,187 I By Sequoia Capital Growth III Principals Fund LLC ( 2 ) Common Shares 09/12/2012 S 515 D $ 9.45 28,039 I By Sequoia Capital Growth Partners III, LP ( 3 )

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 (MM/DD/YY) 3A. Deemed Execution Date, if any (MM/DD/YY) 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 (MM/DD/YY) 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 V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares

Reporting Owners Reporting Owner Name / Address Relationships Director 10% Owner Officer Other SCGF III MANAGEMENT LLC 3000 SAND HILL ROAD, 4-250 MENLO PARK, CA94025 X Sequoia Capital Growth Fund III AIV L P 3000 SAND HILL ROAD, 4-250 MENLO PARK, CA94025 X SEQUOIA CAPITAL GROWTH III PRINCIPALS FUND 3000 SAND HILL ROAD, 4-250 MENLO PARK, CA94025 X SEQUOIA CAPITAL GROWTH PARTNERS III 3000 SAND HILL ROAD, 4-250 MENLO PARK, CA94025 X Signatures /s/ Melinda Dunn, as attorney-in-fact for Douglas Leone, a managing member of SCGF III Management, LLC 09/13/2012 Signature of Reporting Person Date /s/ Melinda Dunn, as attorney-in-fact for Douglas Leone, a managing member of SCGF III Management, LLC, which is the general partner of Sequoia Capital Growth Fund III AIV, LP 09/13/2012 Signature of Reporting Person Date /s/ Melinda Dunn, as attorney-in-fact for Douglas Leone, a managing member of SCGF III Management, LLC, which is the managing member of Sequoia Capital Growth III Principals Fund LLC 09/13/2012 Signature of Reporting Person Date /s/ Melinda Dunn, as attorney-in-fact for Douglas Leone, a managing member of SCGF III Management, LLC, which is the general partner of Sequoia Capital Growth Partners III, LP 09/13/2012 Signature of Reporting Person Date

Explanation of Responses:

( 1 )Shares held directly by Sequoia Capital Growth Fund III AIV, LP ("SC AIV"). SCGF III Management, LLC ("SCGF LLC"), is the general partner of SC AIV and may be deemed to share voting and dispositive power with respect to the shares held by SC AIV. SCGF LLC disclaims beneficial ownership of the securities held by SC AIV except to the extent of its pecuniary interest therein, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for purposes of Section 16 or for any other purpose. ( 2 )Shares held directly by Sequoia Capital Growth III Principals Fund LLC ("SC Principals"). SCGF LLC, is the managing member of SC Principals and may be deemed to share voting and dispositive power with respect to the shares held by SC Principals. SCGF LLC disclaims beneficial ownership of the securities held by SC Principals except to the extent of its pecuniary interests therein, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for purposes of Section 16 or for any other purpose. ( 3 )Shares held directly by Sequoia Capital Growth Partners III, LP ("SC Partners"). SCGF LLC, is the general partner of SC Partners and may be deemed to share voting and dispositive power with respect to the shares held by SC Partners. SCGF LLC disclaims beneficial ownership of the securities held by SC Partners except to the extent of its pecuniary interests therein, and the inclusion of these securities in this report shall not be deemed an admission of beneficial ownership of the reported securities for purposes of Section 16 or for any other purpose.

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.

* 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).

Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
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 Number.