 Though NASCAR typically promotes competition between multiple brands, including those that sponsor the sport and individual races, the sanctioning body provides exclusive protection to its series title sponsors, such as Monster Energy in the Cup Series, as well as current fuel supplier Sunoco.This policy, known as the Viceroy rule, prevents sponsorship from direct competitors within a certain series, although it does not prevent a company from moving to a different series within the sport, or advertising a product that does not directly conflict with the title sponsor.For example, Royal Dutch Shell, Texaco and other oil companies have been allowed to promote their motor oil brands (Pennzoil and Havoline respectively) but not their gasoline products.