[Open-Circuit] Announcement of Consolidated Net Revenue for March 2026

1. Date of occurrence: 115/04/09 2. Company name: Open-Circuit Technology Industrial Co., Ltd. 3. Relationship with company (enter 'parent company' or 'subsidiary'): Parent company 4. Proportion of cross-held shares: Not applicable 5. Reason for occurrence: Not applicable 6. Countermeasures: Not applicable 7. Other matters that need to be described (If the subject of the event occurrence or resolution is a publicly issued company or above, this major information also meets the requirements of Article 7, Item 9 of the Enforcement Rules of the Securities Transaction Act regarding matters that have a significant impact on shareholder equity or stock prices): The company's consolidated net revenue for March 2026 is NT$995,336,000. Keywords: Major Information