TBC Retail Group's business is always going in circles, but that just makes it well-rounded. A subsidiary of private-brand tire supplier TBC, the company operates more than 730 Tire Kingdom, National Tire and Battery, and Merchant's tire and automotive service outlets in more than 20 states. It also has about 490 Big O Tires retail franchises. TBC Retail's locations market such national brands as Michelin, Goodyear, and Uniroyal, as well as its parent's own Sigma brand. (Tire sales account for about 60% of business.) Operations abroad are handled by TBC International. The company began in 1972 inside a stall at the West Palm Beach Farmers Market. Until 2009 it operated as Tire Kingdom.