The Volkswagen group owns about 12 brands and dominates some markets. Why? 

Great piece on the Autoextremist:

We only have to look as far as the VW Group to see how things are dramatically unfolding. As most industry insiders know, the VW Group, led by the maniacal genius, Ferdinand Piech, is on an unbelievable roll right now. The VW Group boasts twelve brands from seven European countries: Volkswagen, Audi, Bentley, Bugatti, Lamborghini, Porsche (and SEAT, SKODA, Ducati motorcycles, Volkswagen Commercial Vehicles, Scania and MAN).

That’s quite a lineup. Normally, it would be a recipe for disaster leading to a train wreck of monumental proportions, a quagmire of dismal profits, hazy brand images, rampant cannibalism among the Group’s brands in the marketplace, and generally a heaping, steaming bowl of Not Good. But somehow, someway the VW Group is orchestrating the most successful array of brands the industry has seen since GM’s heyday (roughly 1957–1977). And they’re doing it in a similar fashion too.