ALPHA & OMEGA SEMICONDUCTOR Ltd

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

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NOTICE OF 2026 ANNUAL GENERAL MEETING OF SHAREHOLDERS

NOTICE IS HEREBY GIVEN that the 2026 Annual General Meeting of Shareholders (the “Annual Meeting”) of Alpha and Omega Semiconductor Limited, a Bermuda exempted limited liability company (“we,” “our,” “us,” or the “Company”), will be held at 8:00 a.m. on Wednesday, November 18, 2026 Taiwan local time (at 4:00 p.m. on Tuesday, November 17, 2026, U.S. Pacific Standard Time), at the Illume Taipei Hotel, No. 100, Dun Hua N Rd., Songshan District, Taipei City, Taiwan, or any other adjournments or postponements thereof, for the following purposes:

1. To elect eight (8) nominees to serve as directors on the Board of Directors of the Company (the “Board”) until the next annual general meeting of shareholders or until their successors are duly elected and qualified;

2. To approve, on an advisory basis, the compensation of the Company’s named executive officers, as described in this Proxy Statement;

3. To approve an amendment and restatement of the Company’s 2018 Omnibus Incentive Plan to, among other things, increase the number of common shares authorized for issuance under such plan from 5,202,000 shares to 6,372,000 shares;

4. To approve an amendment to the Company’s 2018 Employee Share Purchase Plan to increase the number of common shares authorized for issuance under such plan from 3,700,000 shares to 5,700,000 shares; and

5. To approve and ratify the appointment of Deloitte & Touche, LLP as the Company’s independent registered public accounting firm, and to authorize the Board, acting through our Audit Committee, to determine the remuneration of such accounting firm, for the fiscal year ending June 30, 2027.

Only holders of common shares of record at the close of business on September 17, 2026, which is the record date for the Annual Meeting, will be entitled to vote at the Annual Meeting and any continuation or adjournment thereof. Your vote is very important. Regardless of whether you plan to attend the Annual Meeting, it is important that your shares be represented and voted at the Annual Meeting, and we hope you will vote as soon as possible. Voting over the Internet or by telephone, by written proxy or voting instruction card will ensure your representation at the Annual Meeting regardless of whether you attend the Annual Meeting.

By order of the Board of Directors,

Mike F. Chang

Chairman of the Board of Directors

Dated September 30, 2026

Important Notice Regarding the Availability of Proxy Materials

For the Annual Meeting to be Held on November 18, 2026 Taiwan Local Time

(November 17, 2026 U.S. Pacific Standard Time)

The Proxy Statement, Proxy Card and Annual Report on Form 10-K for fiscal year 2026 are available at:

http://www.investorvote.com/AOSL

PROXY STATEMENT

FOR THE 2026 ANNUAL GENERAL MEETING OF SHAREHOLDERS