X0508 4 2026-03-06 0 0001158114 APPLIED OPTOELECTRONICS, INC. AAOI 0001587425 Chen Min-Chu (Mike) C/O APPLIED OPTOELECTRONICS, INC. 13139 JESS PIRTLE BLVD. SUGAR LAND TX 77478 1 0 0 0 0 Common Stock, $.001 par value 2026-03-06 4 S 0 2500 97.00 D 20000 I By Spouse Common Stock, $.001 par value 2026-03-09 4 S 0 8835 108.7172 D 169300 D Held directly by Yuh-Mei Chung, the spouse of Min-Chu (Mike) Chen. Mr. Chen disclaims beneficial ownership of all securities that may be deemed to be beneficially owned by his spouse, except to the extent of any indirect pecuniary interest therein The shares were sold in multiple transactions at actual sale prices ranging from $105.50 to $110.20 per share. The price reported reflects the weighted average sale price for the transactions. The reporting person undertakes to provide upon request by the SEC staff, the issuer, or a security holder of the issuer, full information regarding the transaction. /s/ David C. Kuo, attorney in fact for Min-Chu (Mike) Chen 2026-03-10