The Black Hills Institute of Geological Research, Inc. (BHI) is a private corporation specializing in the excavation and preparation of fossils, as well as the sale of both original fossil material and museum-quality replicas. Founded in 1974 and based in Hill City, South Dakota, the company is most famous for excavating and selling replicas of some of the most complete specimens of Tyrannosaurus rex, including "Sue" and "Stan." In 1992, the remains of "Sue" were seized from the BHI by the Federal Bureau of Investigation and were auctioned off five years later to the Field Museum of Natural History in Chicago, Illinois for US$7.6 million — the highest price ever paid for a fossil. BHI owners founded the Black Hills Museum of Natural History in Hill City in March, 1992, a non-profit paleontological museum which is controlled by an independent Board of Directors.