International Speedway Corporation or ISC is a corporation whose primary business is the ownership and management of NASCAR race tracks. About 55% of the stock in ISC is owned by the heirs of NASCAR founder William France Sr. and the remainder trades on the stock market. Although ISC is majority-owned by the France family, it is separate from NASCAR.
The corporation owns California Speedway, Darlington Raceway, Daytona International Speedway, Homestead-Miami Speedway, Kansas Speedway, Martinsville Speedway, Michigan International Speedway, Phoenix International Raceway, Richmond International Raceway, Talladega Superspeedway, and the Watkins Glen International road course and owns a minority interest in Chicagoland Speedway. Together these tracks hold slightly less than two-thirds of the events on the NASCAR Sprint Cup Series schedule. ISC has also agreed to purchase 600 acres (2.4 km²) on Staten Island in New York for the construction of a new speedway.
In 2005, Kentucky Speedway filed a lawsuit against ISC and NASCAR, claiming that NASCAR violated federal antitrust laws by not awarding them a Sprint Cup race, noting the close relationship between NASCAR, ISC, and the France Family.
The company's other holdings include the Motor Racing Network, a radio network that broadcasts NASCAR events, Americrown, a food service business that operates concession stands at its tracks, and DAYTONA USA, an attraction just outside Daytona International Speedway. In 2006, ISC partnered with Speedway Motorsports, Inc. to form Motorsports Authentics, a company that markets and distributes NASCAR-related souvenirs and collectibles.