According to many, the formula for Coke is the most famous trade secret of them all. When Coke, at the end of the 19th century, decided not to patent its formula, it did so for one reason: to keep it secret, forever. In May 2006, a Coke employee and two others were charged with stealing and trying to sell guarded Coke secrets to Pepsi. Pepsi notified Coke of the breach and the FBI was called in.