The Group's GHG emissions are classified as direct emissions, energy indirect emissions, and other indirect emissions. Direct sources include process gases—perfluorocarbons (PFCs), nitrous oxide (N2O), methane (CH4), and carbon dioxide (CO2); fuels such as natural gas, liquefied petroleum gas, gasoline, and diesel used in volatile organic compound abatement equipment, emergency generators, and other facilities; and fugitive sources including septic tanks, fire drills, and firefighting equipment. Energy indirect emissions arise mainly from purchased electricity. Other indirect emissions include transportation of products and raw materials, supplier production, employee business travel, waste treatment, and employee commuting.

In 2025, the Group's total location-based GHG emissions—including direct, indirect, and other indirect emissions—were 534,171.580 tCO2e, while total market-based emissions were 436,122.768 tCO2e. Perfluorocarbons were the largest Scope 1 source, accounting for approximately 87.01% of Scope 1 emissions. Scope 2 emissions decreased by 52.94% year over year on a market basis for two principal reasons: China sites used 100% green electricity, reducing carbon emissions, and the Group's numerous energy-saving measures delivered results. Energy indirect emissions from electricity use were the Group's principal operational emissions source and accounted for 26.35% of total Group emissions on a market basis. Scope 3 Category 1 was the largest category overall, accounting for 44.89% of total Group emissions on a market basis. Through inventories conducted under the GHG Protocol, the Group comprehensively understands emissions across scopes and categories and establishes corresponding reduction targets and measures.

 By incorporating green design concepts, the Group continuously improves product e iciency, quality, and service life and makes products more environmentally friendly throughout their life cycles. Patent portfolio development and trade secret management protect the company's intellectual property, sustain its strong competitiveness, and strengthen resilience for innovation and growth. The Group has also introduced green patent and green-trade secret systems to encourage green design proposals.

The Group continues to monitor external low-carbon technologies. It established the Innovative Technology Task Force and introduced an ESG return on investment (ESG ROI) assessment mechanism to analyze the investment benefits of emerging ESG technologies and continuously explore and develop sustainable innovations that deliver both environmental and economic value.

The Group's inventories show that electricity use is its principal source of emissions. It therefore continues to promote third-party ISO 50001 certification at Group sites and uses the PDCA management cycle to improve energy e iciency, reduce energy costs, and lower product carbon footprints.

To advance the circular economy, the Group works with external partners to ensure that waste is properly managed in environmentally sound ways and collaborates with suppliers to assess the feasibility of waste recovery and reuse. Examples include recovering organic solvents and waste ammonia for use as raw materials by downstream companies and implementing recovery and reduction measures for scrap metals and hazardous substances. These e orts increase resource recovery and substantially reduce the likelihood that waste will be released into the atmosphere or leak into water and soil.

To reduce its carbon footprint, the Group incorporates local procurement strategies and increases the proportion of local suppliers. It also continues to conduct supplier ESG surveys. In 2024, the Group held its first supplier carbon reduction support workshop and a supplier conference that brought together supply chain partners to exchange ESG knowledge and communicate Ennostar Group's carbon reduction targets, inviting suppliers to work together to reduce value chain emissions.

In smart manufacturing, the Group plans to build a digital system to support data collection and management. The system will be launched in stages in 2027 and will e ectively inventory emissions from activities and processes. Platform-based data analysis will identify emissions hotspots and opportunities and strategies for reduction. The carbon-management system will continue to be optimized in response to new regulations and technological developments to ensure its performance and adaptability.

To achieve carbon reduction targets and respond to domestic and international carbon fee and carbon tax regulations, the Group plans to introduce internal carbon pricing (ICP) and piloted one project in 2023. Using a shadow-price model and the initial price then proposed by Taiwan's Ministry of Environment—NT$300 per metric ton—the Group incorporated carbon cost into the decision to install fluorinated-gas abatement equipment and shortened the installation schedule from four years to two. The project integrated carbon cost into business processes, promoting more comprehensive internal assessment and management.