 He explained where the string came from and the owners quickly asked him to send samples over for a market test.Two weeks later, Wham-O signed a contract with Fish and Cox to license the product now known as Silly String.Silly String was licensed to and produced by Wham-O, in a range of colours including blue, red, and green, until the Car-Freshner Corporation, the maker of Little Trees, acquired the Silly String trademark in 1997.