How much is a smell worth? A lot, it seems, to multinational toy company Hasbro. Last month, the group submitted an application to trademark the distinctive scent of Play-Doh in the US. The application to the US's Patent and Trademark Office (USPTO), covers all toy modelling compounds. t describes Play-Doh’s particular smell as “a unique scent formed through the combination of a sweet, slightly musky, vanilla-like fragrance, with slight overtones of cherry, and the natural smell of a salted, wheat-based dough.” A container of Play-Doh was sent to the USPTO as part of the application process. Lee Curtis, a partner and chartered trademark attorney at law firm HGF, said: “Hasbro’s trade mark application shows that the use of smells in branding, and companies desire to protect them is increasing.” While it is rare for smells to be successfully trademarked in the US, it is not unheard of. According to Mr Curtis, the first was a flowery scent used on yarn, registered in 1990.