Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers On June 4, 2026, the shareholders of Applied Optoelectronics, Inc. (the “ Company”) approved Applied Optoelectronics, Inc. 2026 Equity Incentive Plan (the “2026 Plan”) at the Company’s 2026 Annual Meeting of Shareholders (the “ Annual Meeting”). The 2026 Plan was previously approved by the Company’s Board of Directors (the “ Board”), upon recommendation by the Company’s Compensation Committee (the “ Committee”), subject to shareholder approval at the Annual Meeting. The 2026 Plan became effective on June 4, 2026, immediately following the Annual Meeting. The 2026 Plan replaces Applied Optoelectronics, Inc. Amended and Restated 2021 Equity Incentive Plan and Amended and Restated 2013 Equity Incentive Plan (together the “ Prior Plans”). No new awards will be granted under the Prior Plans. The following is a summary of the principal provisions of the 2026 Plan. The following summary does not purport to be complete and is qualified in its entirety by reference to the full text of the 2026 Plan, which was attached as Appendix A to the Company’s definitive proxy statement on Schedule 14A filed on April 24, 2026 (the “ Definitive Proxy Statement”) and is incorporated herein by reference. In addition, a more detailed summary of the 2026 Plan can be found on pages 53-59 of the Definitive Proxy Statement, which description is incorporated herein by reference. The 2026 Plan authorizes the issuance of an additional 2,500,000 shares of the Company’s common stock. In addition to these newly authorized shares, any shares previously reserved and available for issuance, but not issued or subject to outstanding awards, under the 2021 Plan as of the effective date of the 2026 Plan will become available for issuance under the 2026 Plan, as will any shares that are subject to outstanding awards under the 2021 Plan as of the effective date of the 2026 Plan to the extent such shares are not issued and cease to be subject to such awards following the effective date of the 2026 Plan. The Board or the Committee is authorized to administer the 2026 Plan. The Board or the Committee may delegate concurrent administration of the 2026 Plan to other committees consisting of one or more members of the Board or to one or more officers in accordance with the 2026 Plan’s terms and any conditions established by the Board or the Committee. The plan administrator is authorized to select the individuals to be granted awards and, subject to the terms of the 2026 Plan, to determine the types of awards to be granted, the number of shares subject to awards and the other terms, conditions and provisions of such awards. Awards may be granted under the 2026 Plan to the Company’s employees, officers, directors, consultants, agents, advisors and independent contractors and those of the Company’s affiliates. Under the 2026 Plan, the Committee may grant stock awards, restricted stock and stock units, performance awards, stock options, stock appreciation rights and other stock or cash-based awards. The foregoing summary of the 2026 Plan and the summary of the 2026 Plan set forth in the Proxy Statement are qualified in their entirety by reference to the full text of the 2026 Plan, which is filed as Exhibit 10.1 to this Current Report.

Item 5.07 Submission of Matters to a Vote of Security Holders. At the Company’s Annual Meeting, holders of an aggregate of 80,047,663 shares of the Company’s common stock at the close of business on April 10, 2026 were entitled to vote at the meeting, of which 51,375,083 or 64.18% of the eligible shares were represented in person or by proxy. The matters voted upon at the Annual Meeting and the final results of those votes were as follows: Proposal No. 1: Election of two Class I Directors. For Withheld Broker Non-Votes ────────────────────────────────────────────────────────────────────────────── Che-Wei Lin 35,667,619 3,227,489 12,479,975 Robert (Bob) Flanagan 37,970,404 924,704 12,479,975 Proposal No. 2: To ratify the appointment of PricewaterhouseCoopers LLP as the Company’s independent registered public accounting firm for the fiscal year ending December 31, 2026. For Against Abstain ──────────────────────────────────────── 51,297,379 38,044 39,660 Proposal No. 3: To approve on an advisory basis, the compensation of the Company’s named executive officers, or the “say-on-pay” vote. For Against Abstain Broker Non-Votes ────────────────────────────────────────────────────────────── 38,001,385 672,239 221,484 12,479,975 Proposal No. 4: To approve the amendment of the Company’s Amended and Restated Certificate of Incorporation, as amended, to clarify the voting standard that applies to certain future amendments. For Against Abstain ──────────────────────────────────────── 38,486,404 305,242 103,462 Proposal No. 5: To approve the 2026 Equity Incentive Plan. For Against Abstain Broker Non-Votes ──────────────────────────────────────────────────────────────── 34,862,167 3,780,336 252,605 12,479,975 Proposal No. 6: To approve the adjournment of the Annual Meeting to a later date, if necessary or appropriate. For Against Abstain ────────────────────────────────────────── 47,987,329 3,100,990 286,764

Item 9.01 Financial Statements and Exhibits. (d) Exhibits 10.1 Applied Optoelectronics, Inc. 2026 Equity Incentive Plan 104 Cover Page Interactive Data File (embedded within the Inline XBRL document). 3 SIGNATURES