It's a case that really takes the biscuit.
But it looks like the makers of Kit Kat, Nestlé, have not been given a break in their efforts to protect its unusual shape.
Judges in the European Court of Appeal dismissed its attempt to have the shape of the four-finger bar trademarked.
For more than a decade the company has tried to protect the chocolate bar from imitations but faced stern objections from the likes of Cadbury and other confectionery manufacturers.
But Wednesday's judgement found that a previous court had been right to throw out the claim - a ruling which could open the door to own-brand imitations by the big supermarkets.
Battle of the biscuits
Although the Kit Kat was introduced into the world by its creators Rowntree's of York in 1935, two years later a similar product, Kvikk Lunsj - pronounced "quick lunch" - appeared in Norway, which is still very popular in the Scandinavian country.
The Norwegian chocolate is produced by Mondelez, which owns Milka, Cadbury, Oreo and Toblerone, and the taste is more like a Milka chocolate.
The two products, which are almost identical, lived alongside each other in relative peace until Nestlé went on the offensive in 2002.
Four years later, the EU granted the trademark to Nestle for the shape of the bars, but this was contested by Mondelez, and since then the court battle has gone back and forth between the two confectionery companies.
The question of distinctiveness
Judges sitting in the Luxembourg court on Wednesday essentially threw out Nestlé's appeal, telling the EU trademark office it has to "reconsider" its decision - annulling Kit Kat's claim.
The case was about whether the brand had become distinctive enough to deserve its trademark - that its shape alone was how people recognise the snack.
In 2016, the court made a similar ruling stating that if Nestlé succeeded in proving that Kit Kat was recognised in all European countries by its shape, it could protect it.
However, in Belgium, Ireland, Greece and Portugal, no evidence had been provided - meaning only the brand was safe.
Nestlé claim no product could ever meet such a strict criteria.
During this time, Mondelez challenged other portions of the ruling, including the classification of Kit Kat as a biscuit rather than a chocolate bar.
In April, one of the most prominent lawyers in the European Court, Melchior Wathelet, commented on the case and suggested that the court should stick to its 2016 ruling and not allow the shape of Kit Kat to be protected.
The court often adheres to such recommendations - but doesn't have to.
Nestlé has been looking for Europe-wide protection for the Kit Kat shape, but there's also been an almost identical case in the UK.
That ended in a 16,000-page ruling that Kit Kat had "no inherent distinctiveness".
In other words, for Kit Kat to acquire distinctiveness, Nestlé must show that the relevant public recognises the shape in itself as originating from Nestlé.
The thin line between success and failure for 3D shape marks
Toy manufacturer LEGO’s attempts to protect its iconic bricks as 3D trademarks is just one of the high profile examples of other brands whose otherwise iconic shapes have failed to meet the criteria for shape marks set by trademark offices, and national and European courts.
Cadbury wanted a distinctive purple hue of the packaging, and Lindt reportedly suggested its rival change their gold wrapper to bronze, and ban the red ribbon, but none of them succeeded.
Toblerone, however, has been granted a trademark in 1998, but last year there was a company that started producing the same chocolate.
Poundland defended the fact that Toblerone had changed the shape of its products to reduce their weight, so that the protection was overwritten by itself.
The two companies finally settled on a deal out of court.