AutoZone Inc. (NYSE: AZO)

AutoZone is the largest auto parts retailer in the US, operating over 7,100 stores across the US, Mexico, and Brazil. The company sells replacement parts, accessories, and maintenance items for cars and trucks. AutoZone caters to both DIY customers (who fix their own cars) and professional mechanics (the DIFM u2014 Do It For Me u2014 segment). The company is famous for its aggressive share buyback program.

Retail sales of auto parts, batteries, oil, filters, and accessories. The commercial (Pro) business selling to repair shops is the faster-growing segment. AutoZone's proprietary brands (Duralast, Valucraft) carry higher margins than national brands. The company has repurchased so many shares that its stockholders' equity is deeply negative u2014 it's essentially funded by debt. Annual revenue exceeds $17 billion.

J.R. "Pitt" Hyde III founded Auto Shack in 1979 in Forrest City, Arkansas (renamed AutoZone in 1987 after RadioShack threatened to sue). The company went public in 1991. AutoZone has repurchased over 90% of its shares outstanding since 1998, making it one of the most aggressive buyback stories in corporate history. The stock has returned over 30,000% since its IPO.