Imagine listing this as one of a company's major assets:

"A sweet, slightly musky, vanilla-like fragrance, with slight overtones of cherry, and the natural smell of a salted, wheat-based dough."

That's something Hasbro can do, certainly now that the US Patent and Trademark Office has accepted the company's trade mark application for the smell of its Play-Doh product. Hasbro has apparently been using this scent since 1956, and it's managed to persuade the US authorities that the scent serves a trade mark function, in that it identifies and distinguishes the product. But what does this really mean? Well, it means that the company now has the exclusive right to use the particular fragrance – as well as fragrances that might be confusingly similar to it – certainly in relation to the goods that are specified in the registration, and possibly also in relation to other goods.

Or perhaps imagine a corporate asset like this:

"The colour red (Pantone 18 1663TP) applied to the sole of a shoe."

That's an asset Christian Louboutin has, certainly after a recent ruling by the Court of Justice of the European Union, following a rather technical referral from a Dutch court as to whether the colour trade mark was limited by the shape of the shoe. The effect of this decision seems to be that Christian Louboutin can now use its Benelux trade mark registration to stop a Dutch company called Van Haren from selling a Christian Louboutin look-alike.

Welcome to the world of unconventional trade marks – smell, colours, shapes, sounds, tastes, gestures, moving logos and more.

Unconventional trade marks are interesting and they're fun, but they're also very difficult to protect. When it comes to scents, the important thing to remember is that the scent must be arbitrary, it must not be the product itself. So, for example, the smell of a perfume or an air freshener would not be registrable as a trade mark. There are some scent registrations in the USA, including one quaint one described as a "floral fragrance reminiscent of plumeria blossom" for yarn and thread.

In Europe, however, scents are a real stinker. For starters, there is a general principle that to be registrable, a trade mark must be "clear, precise, self-contained, easily accessible, intelligible, durable and objective." In addition, there is the famous case of Ralph Sieckmann, which involved an application to register a scent described as "balsamically fruity with a hint of cinnamon." In that instance, the sniffy European authorities held that the requirement of a graphical representation of a trade mark is not satisfied by a chemical formula, a written description, or a deposit of an odour sample. Unfortunately, they didn't tell us what would pass the smell test.

Colours are difficult too, but they're not as difficult as scents. In the USA, a single colour can be registered as a trade mark provided that it isn't functional, and provided that it is, in fact, distinctive of one company. The colour pink is a registered trade mark for roof insulation (Owens Corning), and this registration has been recognised by the Supreme Court. Colour registrations have been granted in the EU, for example, the colour orange for champagne in the name of Veuve Clicquot.

When it comes to a colour mark, the most obvious way to describe it is by specifying the Pantone number. In the case of a colour combination, however, it may be necessary to also spatially limit the colours. But even specifying a Pantone number may not be enough. As Cadbury discovered a few years back, when a UK court decided that its description of its mauve trade mark as the colour Pantone 2685C "applied to the whole visible surface, or being the predominant colour applied to the whole of the visible surface of the packaging" was not sufficiently clear for competitors or potential competitors to understand. Cadbury were also unsuccessful in their attempt to register the colour purple as a trade mark in respect of chocolate slabs in South Africa.

In South Africa, some colour trade marks have been registered, but we're not aware of any scent registrations. There is no direct prohibition though, and the legislation has a non-exclusive list of what might comprise a trade mark. This reads as follows: "a device, name, signature, word, letter, numeral, shape, configuration, pattern, ornamentation, colour or containers for goods or any combination of the aforementioned." In trade mark matters, South African courts tend to look to the EU for guidance rather than the USA. That probably doesn't augur well for scent trade marks.

When it comes to branding, companies should definitely be thinking beyond names and logos, but they should also know that protection isn't always straightforward.

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