Kentucky Fried Secret
In 1952, the owner of a chicken restaurant named Harlan Sanders began franchising out his brand to other restaurateurs throughout the country. Colonel Sanders’ chain, then known as Kentucky Fried Chicken (and now KFC), spread quickly, and Sanders became a very wealthy man. The key to his success: a secret recipe. It would have been easier to simply give the franchisees the herb and spice recipe mix and prohibit its unauthorized use via contracts and patents. But KFC decided not to, believing that the recipe was their biggest point of differentiation. And the recipe remains a secret even today -- in no small part because the company wants to keep it that way. More from Now I Know .