It is the third application to the Patent Office to register a smell since such registrations became possible in October. Of the other two, from Chanel and a Japanese tyre company, neither has yet been successful.
Unicorn Products plan to inject the smell into a new range of flights which are designed, as they spin through the air, to give off the essential fragrance of British pubs. The flights would be impregnated with capsules of the smell which would burst open when the surface was touched, thereby creating the necessary public bar atmosphere.
The Patent Office's trade marks examiners are now investigating whether the "strong smell of bitter beer" is distinctive enough to warrant a trade mark. One obstacle to registration may be the fact that untold thousands of darts carry the smell already, having soaked it up from spilt beer on pub bars and tables.
"We will apply a number of tests. The aroma cannot be inherent in the product and customers have to recognise the smell of the product as belonging to that company. It also has to be exclusive to the product," said Richard Dickinson of the South Wales-based Patent Office.
In the USA, where it has been possible to register smells for some time, only one application, for a plum-like smell intended to be associated with embroidery products, has been successful.
Stanley Lowy, chairman and managing director of the Unicorn operation, is still optimistic that his project will prove to be more than just a flight of fancy.
"The idea is that as you finger the plastic covering of the flights the aroma is given off, in the same way that those tear-out perfume advertisements in glossy magazines work," he says.