The Coca-Cola Company and PepsiCo are two distinct businesses. Although their flagship goods are similar, they have been direct competitors since the early twentieth century.
Given the magnitude of both corporations and their dominant positions in the soda and snack food markets, they are unlikely to be affiliated. Antitrust and anti-collusion laws are in place all over the world to prevent corporations from taking advantage of the market by gaining majority control or exchanging information. Other beverage companies, such as Dr. Pepper Snapple, have enough market share to keep the two major competitors from stagnating.