The battle to stop people from copying shapes

It's rare for a three-dimensional object to be granted trademark status, but not unheard of. The shape of a four-finger KitKat may not be judged distinctive enough to qualify as a trademark, but those of Toblerone and Nestle's Walnut Whip are.
Coca-Cola first received the status for the contours of its bottle from the US Patent and Trademark Office as far back as 1960.

There can be huge benefits for firms that are granted trademark status. Unlike patents, which expire after 20 years, a trademark can potentially last forever - thus effectively conferring a long-term monopoly on a particular shape.
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Firstly, the law requires that the shape is sufficiently distinctive, says Luke McDonagh, an expert in intellectual property law at City University London.
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There's a second requirement. A trademark must not effectively give a technical monopoly to one company. 
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