The Group's subsidiaries provide upstream and downstream LED products and integrated services designed to address customers' di erent product design requirements. With a spirit of mutual support and shared progress, the Group uses extensive industry knowledge, precise insights, and innovative production technologies to support diverse partners and needs. It provides the most appropriate collaboration model for each customer's requirements, continuously improving customer satisfaction and strengthening customer partnerships.

To ensure e ective communication and information exchange with customers, the Group has established internal procedures including the Customer Communication Management Procedure, Customer Satisfaction Survey Procedure, and Customer Complaint Handling Procedure. Systematic and standardized communication modules and processes improve customer-service quality and provide references for production and sales planning, product development and improvement, and promotional strategies.

To gain deeper insight into client needs and issues and improve service quality, the Group conducts a customer satisfaction survey once each year. The survey gathers customers' recommendations concerning technology, delivery, service, and product quality, and captures their expectations and suggestions. Results are analyzed, assigned to relevant internal functions for follow-up, and used to establish improvement plans. Customer satisfaction findings also inform the company's future strategic planning.

Before the annual customer satisfaction survey, the customer-service functions of Ennostar Corporation, Episky, Epicrystal, and Canyang track progress through relevant meetings. A er the survey, senior management reports the year's results and proposes continuous improvement initiatives. Customer satisfaction declined in 2025 from 2024 due to U.S. tari s, geopolitical conditions, a sluggish overall economy, and supply-demand imbalances. Ennostar Corporation's DBO will continue to improve service quality and corrective action e iciency through Co-activation Service, creating mutually beneficial outcomes with customers. Lextar also responds directly to client needs and validates improvements through regular quarterly business review (QBR) meetings. The Group will continue optimizing customer-service processes, adjusting resources, and improving management to increase satisfaction.

The customer-service function consolidates customer satisfaction survey results into an analytical report and submits it for review by relevant managers, including the President's O ice, sales, and quality functions. Comments, preventive actions, and corrective measures proposed by other internal functions may be incorporated into the report. The customer-service function presents the survey findings at internal management or senior-level meetings and submits them to the President for review and discussion of improvement directions or strategies. Relevant functions then implement the required improvements or adjustments in accordance with meeting conclusions.

Customer satisfaction survey results serve as a reference for corporate strategic planning and continuous improvement, enabling the Group to meet customers' actual needs and further enhance competitiveness.

Under the Group's quality policy, continuous quality improvement and innovation are pursued to meet client needs and increase satisfaction. When the sales function receives a report of a product quality abnormality, the Group immediately activates its internal process, confirms the issue with the customer, clarifies the symptoms, promptly reports the matter to the responsible internal function, and retrieves the complained-of product for analysis. Once the root cause has been identified internally, preliminary findings are reported to the customer together with an update on analytical progress. The responsible function then develops countermeasures based on the root cause, the customer-service function communicates them to the customer, and the responsible function implements them. Depending on the issue and corrective actions, lessons learned are applied horizontally, and subsequent product return or exchange, transportation, and analytical-report arrangements are coordinated, with prevention of recurrence as the highest priority.

All product-related complaints received in 2025 were answered promptly with response measures. E ectiveness was verified a er corrective actions were implemented for each case.

Products are recalled when a quality abnormality could cause customers significant losses or create concerns about the service life of their products. Sales recalls are improved through the corrective and preventive action mechanism, and completion and e ectiveness of the measures are tracked and confirmed. Through continuous improvement of its quality system, together with routine monitoring, detection, and preventive measures, the Group identifies abnormalities early and reduces their e ects on customers. No major sales recalls occurred in 2025.

At Ennostar Corporation, the function issuing the recall request—such as integration or engineering identifies a ected risk lots based on the root cause analysis in the corrective and preventive action form or customer complaint form and requests recall of a ected lots already shipped. Sales reviews the recall's impact on customers, assesses whether a recall is warranted based on the actual circumstances, and tracks the quantities recalled.

Lextar classifies recall severity from Level 1 to Level 4. A Level 2 or higher market-return risk that triggers a recall at a customer's site must be reported to the quality management representative within two hours. A Level 3 or higher risk triggering a regional-market recall must be reported to the President within two hours. A Level 4 risk triggering a global-market recall must be reported to the Chairman within two hours.