First Quantum said that Zambia's tax agency had demanded the taxes, saying they were on import duties, penalties and interest on consumables and spare parts.
A U.S. court ruled that the Chaupe family case against Newmont Mining Corporation should be heard in Peru - not Delaware, where the company incorporated almost 100 years ago.
La Oroya polymetallic smelter had been operated by Doe Run Peru, a unit of the U.S.-based Renco Group, from 1997 until the company went bankrupt in 2009 and its assets were transferred to a group of former creditors.