Company: AAOI
Filing Date: 2025-05-28
Form Type: 424B5
Source: 0001104659-25-053547
Chunk: 19

Company: APPLIED OPTOELECTRONICS, INC.
Filing Date: 2025-05-28
Form: 424B5
Chunk 19
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 the extent required by Regulation M, the Agents will not engage in any market making activities involving our common stock while the offering is ongoing under this prospectus supplement.

This prospectus supplement and the accompanying base prospectus in electronic format may be made available on websites maintained by Raymond James and Needham, and they may distribute this prospectus supplement and the accompanying base prospectus electronically.

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TABLE OF CONTENTS

### LEGAL MATTERS
The validity of the common stock offered by this prospectus supplement will be passed upon by Haynes and Boone, LLP, Houston, Texas. The Agents are being represented in connection with this offering by Mayer Brown LLP, New York, New York.

### EXPERTS
The audited financial statements and management’s assessment of the effectiveness of internal control over financial reporting incorporated by reference in this prospectus supplement and elsewhere in the registration statement of which the accompanying base prospectus forms a part have been so incorporated by reference in reliance upon the reports of Grant Thornton LLP, independent registered public accountants, upon the authority of said firm as experts in accounting and auditing.

### WHERE TO LEARN MORE ABOUT US
We have filed with the SEC a registration statement on Form S-3ASR under the Securities Act with respect to the securities being offered under this prospectus supplement. This prospectus supplement and the accompanying base prospectus, which forms part of the registration statement, do not contain all of the information in the registration statement. We have omitted certain parts of the registration statement, as permitted by the rules and regulations of the SEC. For further information regarding us and our securities, please see the registration statement and our other filings with the SEC, including our annual, quarterly, and current reports and any proxy statements. Our public filings with the SEC are available to the public on the SEC’s Internet website at http://www.sec.gov.

We furnish holders of our common stock with annual reports containing audited financial statements prepared in accordance with accounting principles generally accepted in the United States following the end of each fiscal year. We file reports and other information with the SEC pursuant to the reporting requirements of the Exchange Act. In addition, the reports, proxy statements and other information that we file with the SEC are available to you free of charge through the Investor Relations page of our website, http://ao-inc.com/, as soon as reasonably practicable after they have been electronically filed with, or furnished to, the SEC. We have included our website address as a textual reference and do not intend it as