The decision at the High Court in London came after rival Cadbury objected to Nestle's attempt to trademark the bar's shape.
LONDON—A British court ruled Wednesday that food giant Nestle cannot register the shape of one of its most famous chocolate bars, the Kit Kat, as a trademark.
Kit Kats are four thin fingers of wafer covered in chocolate which were originally created in Britain in 1935.
The decision at the High Court in London came after U.S.-owned rival food company Cadbury objected to Swiss firm Nestle's attempt to trademark the bar's shape.
Nestle said it planned to appeal against the ruling, which it said could open the door for Cadbury to produce a similar product.
"They couldn't call it Kit Kat but they could produce something in that shape," a company spokesman said.
"We believe that the shape deserves to be protected as a trademark in the UK and are disappointed that the court did not agree on this occasion."
A spokeswoman for Cadbury could not comment on whether it planned to produce a chocolate bar along the same lines.
Copyright Agence France-Presse, 2016