A mass tort is a civil action involving numerous plaintiffs against one or a few corporate defendants. The tort may involve, for example, personal injuries suffered by numerous plaintiffs as a result of a defective product, or a mass disaster in which there were many injured persons, such as an airplane crash, or exposure of a large group of people to toxic chemicals or pharmaceuticals.
Keystone is an unincorporated community in central Keith County, Nebraska, United States. It lies along local roads near the North Platte River, northeast of the city of Ogallala, the county seat of Keith County. Its elevation is 3,100 feet (945 m). Although Keystone is unincorporated, it has a post office, with the ZIP code of 69144.