Nippon Sheet Glass Co., Ltd. (日本板硝子株式会社, Nihon Ita-Garasu Kabushiki-gaisha) is a Japanese glass manufacturing company. In 2006 it purchased Pilkington of the United Kingdom. This makes NSG/Pilkington one of the four largest glass companies in the world alongside with another Japanese company Asahi Glass, Saint-Gobain, and Guardian Industries.The company is listed on the Tokyo Stock Exchange and is a constituent of the Nikkei 225 stock index.