JUNE 8, 2021 MARCH 19, 2021 GC HELD THE “INTELLIGENT PIPELINES INFRASTRUCTURE – WATER PIPING SYSTEM & DESIGN SOLUTION” SEMINAR TO ENHANCE THE PIPE MANUFACTURING INDUSTRY IN THAILAND GC held the “Intelligent Pipelines Infrastructure –Water Piping System & Design Solution” seminar to enhance the pipe manufacturing industry and polymer products business in Thailand at The Energy Complex Building in Bangkok. This effort highlighted GC’s commitment to develop polymer products in response to the piping needs of its customers and partners through collaboration among its partners in every sector. This should help enable Thai piping products to compete at the international level and to be part of the “thinking buddy” in improving the Thai pipe manufacturing industry. GC REDUCED ITS STAKE IN GLOBAL POWER SYNERGY PCL GC informed The Stock Exchange of Thailand of its sale of Global Power Synergy PCL (GPSC) common stock. GC sold 305,000,000 shares, representing 10.82% of GPSC’s available shares, to PTT PCL. Also 53,936,756 shares were sold to Siam Management Holding Co., Ltd. (1.91% of GPSC’s available shares). MARCH 25, 2021 GC ANNOUNCED THE DELISTING OF VINYTHAI PLC FROM LISTED SECURITIES AND A TENDER OFFER TO STRENGTHEN DOWNSTREAM CHEMICAL PRODUCTS AND DRIVE EXPANSION INTO CLMV MARKETS GC informed The Stock Exchange of Thailand of its Board resolution to delist VinyThai PLC (VNT) from listed securities and tender offer for VNT securities. AGC Inc. (AGC) as a major stockholder of VNT does not intend to sell its shares of VNT common stock. After VNT securities are delisted, GC and AGC have plan to merge VNT and AGC Chemicals Co. , Ltd. (AGC-TH) (a subsidiary with all shares held by AGC). Before the merger, AGC-TH will reorganize by merging PVC under AGC in Vietnam into AGC-TH. Post-merger, GC may consider buying rights offerings in the new company with volumes and prices to be considered later. This investment will drive the capacity, strength, and development of the downstream businesses of GC, which are PVC and Chlor-Alkali both of which continue to experience rising demand in line with the economic growth. Moreover, this gives an opportunity for GC to expand into CLMV countries. In total, 358,936,756 shares (~12.73% of GPSC’s available shares) were sold. The GPSC’s common stock was sold to the contractual party on June 8, 2021. GC reduced its ownership of GPSC from 22.73% to 10% through these transactions. The sale is accordance with GC’s strategy to divest from non-core business while focusing on increasing its performance chemicals business lines. 15 BUSINESS OPERATION AND PERFORMANCE CORPORATE GOVERNANCE FINANCIAL REPORTS AND FINANCIAL STATEMENTS APPENDIX MAJOR EVENTS AND ACTIVITIES IN 2021