The UK High Court has ruled that KitKat cannot trademark the shape of its four-finger bars.
The ruling is the latest in a long running dispute with Cadbury.
Nestlé wanted to stop other chocolate-makers like its rival Cadbury from producing a similar shaped chocolate bar. But the UK High Court ruled against the trademark, arguing that other four-finger bars exist that customers do not confuse with KitKats.
Nestle said it will appeal the judgement.
“KitKat is much loved and the iconic shape of the four-finger bar, which has been used in the UK for more than 80 years, is well known by consumers," a spokesman said.
"We believe that the shape deserves to be protected as a trade mark in the UK and are disappointed that the court did not agree on this occasion."
Nestle argued that its four-finger bar had been associated with the company since it was launched in 1935, citing a survey that showed 90% of people associated an unbranded four-finger chocolate bar with Nestle.
But its case was weakened by the existence of a similar, Norwegian product - Kvikk Lunsj, meaning ‘quick lunch’ - that has been around since 1937.
The legal battle was the latest in a long-running chocolate war with Cadbury, which had launched a challenge to Nestlé's attempts to patent the design in court.
The decade-long dispute started when Cadbury sought to trademark the colour purple.
Nestlé succeeded in overturning the purple trademark in 2013 and Cadbury has been seeking retribution ever since.
