Recent research conducted at the University of Illinois Swine Research Center demonstrated positive effects of feeding copper hydroxychloride to weanling pigs, including improved growth performance and positive changes in intestinal health. It is, however, not known if copper hydroxychloride would also elicit positive effects in growing-finishing pigs. Additionally, it is also not known if the positive effects of copper hydroxychloride are obtained regardless of the origin of the mineral, or if the response is specific to the product produced by a specific supplier. Therefore, an experiment was conducted to test the hypothesis that inclusion of copper hydroxychloride in diets for growing-finishing pigs would improve growth performance, and secondly that the origin of the copper hydroxychloride is not important for the outcome.