Company: AAOI
Filing Date: 2025-02-28
Form Type: 424B5
Source: 0001104659-25-019109
Chunk: 21

Company: APPLIED OPTOELECTRONICS, INC.
Filing Date: 2025-02-28
Form: 424B5
Chunk 21
---
 a copy of any or all of the foregoing documents and information that has been or may be incorporated in this prospectus supplement by reference, other than exhibits to such documents. Requests for such documents and information should be directed to:

<div align='center'>Applied Optoelectronics, Inc. 
 Attn: Dr. Stefan Murry, Chief Financial Officer 
 13139 Jess Pirtle Blvd. 
 Sugar Land, TX 77478 
 (281) 295-1800</div>

You may also access the documents incorporated by reference in this prospectus supplement through our website at http://ao-inc.com/ ​. Except for the specific incorporated documents listed above, no information available on or through our website shall be deemed to be incorporated in this prospectus supplement.

<div align='center'>S-14</div>

TABLE OF CONTENTS

#### Prospectus

#### APPLIED OPTOELECTRONICS, INC.

#### Common Stock

#### Preferred Stock

#### Debt Securities

#### Warrants

#### Units
**We may offer and sell any combination of the securities listed above from time to time, in one or more classes or series and in amounts, at prices and on terms that we will determine at the time of the offering.

In addition, selling securityholders may offer and sell, from time to time, these securities on terms described in a prospectus supplement. We will not receive any proceeds from the sale of our securities by the selling securityholders.

This prospectus provides you with a general description of the securities we may offer. Each time we or selling securityholders sell securities, we or such selling securityholders will provide a supplement to this prospectus that contains specific information about the offering and, if applicable, the selling securityholders, as well as the amounts, prices and terms of the securities. The prospectus supplement may also add, update or change information contained in this prospectus. You should carefully read this prospectus, all prospectus supplements and all other documents incorporated by reference in this prospectus before you invest in our securities.

We or selling securityholders may offer and sell these securities in the same offering or in separate offerings through underwriters, dealers or agents or directly to purchasers, on a continuous or delayed basis. The prospectus supplement for each offering will describe in detail the plan of distribution for that offering and will set forth the names of any underwriters, dealers or agents involved in the offering and any applicable fees, commissions or discount arrangements. See “Plan of Distribution.”

We encourage you to carefully review and consider