Tranche Update on Idemitsu Kosan Co.,Ltd.'s Equity Buyback Plan announced on February 14, 2023.

Idemitsu Kosan Co., Ltd. is specialized in the production and refining of petroleum products. Net sales break down by category as follows: - refining of petroleum products (78.8%): fuels, lubricants, kerosene, etc. At the end of March 2019, the group operated 6 refineries in Japan; - manufacturing of petrochemical products (12.5%): activity carried out in 2 production sites located in Japan; - exploration and production of oil, coal, uranium and geothermal resources (7%); - other (1.7%). Net sales are distributed geographically as follows: Japan (69.8%), Asia-Pacific (19.2%), North America (7.2%), Europe (2.4%) and others (1.4%).