Company: AAOI
Filing Date: 2025-11-07
Form Type: 424B5
Source: 0001104659-25-108494
Chunk: 3

Company: APPLIED OPTOELECTRONICS, INC.
Filing Date: 2025-11-07
Form: 424B5
Chunk 3
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 prospectus supplement and the accompanying base prospectus outside the United States. This prospectus supplement and the accompanying base prospectus do not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus supplement and the accompanying base prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

References in this prospectus supplement to the “Company,” “we,” “us” and “our” and similar terms refer to Applied Optoelectronics, Inc.

We have filed or incorporated by reference exhibits to the registration statement of which this prospectus supplement forms a part. You should read the exhibits carefully for provisions that may be important to you.

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TABLE OF CONTENTS

### PROSPECTUS SUPPLEMENT SUMMARY
This summary description about us, our business and this offering highlights selected information contained elsewhere in this prospectus supplement or incorporated in this prospectus supplement by reference. This summary does not contain all of the information you should consider before deciding to invest in our common stock. You should carefully read this entire prospectus supplement, the accompanying base prospectus and any free writing prospectus that we have authorized for use in connection with this offering, including each of the documents incorporated herein or therein by reference, before making an investment decision. Investors should carefully consider the information set forth under “Risk Factors” beginning on page S-5 and incorporated by reference to our annual report on Form 10-K and our quarterly reports on Form 10-Q.

#### The Company
We are a leading, vertically integrated provider of fiber-optic networking products. We target four networking end-markets: internet data centers, cable television (“CATV”), telecommunications (“telecom”), and fiber-to-the-home (“FTTH”). We design and manufacture a range of optical communications products at varying levels of integration, from components, subassemblies and modules to complete turn-key equipment.

In designing products for our customers, we typically begin with the fundamental building blocks of lasers and laser components. From these foundational products, we design and manufacture a wide range of products to meet our customers’ needs and specifications, and such products differ from each other by their end market, intended use and level of integration. We are primarily focused on the higher-performance segments within the internet data center, CATV, telecom and FTTH markets, which increasingly demand faster connectivity and innovation.

The four end markets we target