住友商事
The San Cristóbal mine was formerly developed by Apex Silver Mines Ltd. of Denver, Colorado, a company founded in 1993. In September 2006, Sumitomo Corporation of Japan acquired a 35% share of the facility in a financing deal. The acquisition was supported by the Japan Bank for International Cooperation and Nippon Export and Investment Insurance (NEXI). Sumitomo Corporation assumed full ownership following Apex Silver's 2009 bankruptcy filing.