The small Irish takeaway chain Supermac’s has won a David v Goliath court battle with McDonald’s over the use of the Big Mac trademark, paving the way for it to open outlets across Europe.

The ruling also means the US-founded fast food multinational has lost the right to use the name “Big Mac” in the EU in relation to chicken burgers.

The decision by the European court of justice (ECJ) ends a marathon nine-year legal fight by the Irish operator against its global rival. A Supermac’s spokesperson said the chain also had a similar case pending in the UK that, if successful, could lead to an expansion into the British market.

The legal tussle began in 2015, when Supermac’s tried to register its name in the EU as a trademark for restaurants, with a view to moving into the rest of Europe, prompting McDonald’s to oppose the application by Supermac’s as a name and a logo.

McDonald’s argued that the name was too similar to its Big Mac burgers and would cause confusion among customers, winning a partial victory in 2016, when Supermac’s was granted the trademark for its restaurant name but not for many items of food and drink.

The following year, the Irish chain founded in 1978 in Ballinasloe, County Galway, filed an application before the EU Intellectual Property Office (EUIPO) to end the exclusive use of the term “Big Mac” by McDonald’s in the bloc.

It argued that the trademark had not been put to genuine use in the EU in connection with a restaurant name within a continuous five-year period, and accused McDonald’s of engaging in “trademark intimidation, registering brand names that are simply set aside to be used against future competitors”.

The EUIPO partly upheld Supermac’s case in 2019, and on Wednesday the ECJ found in its favour with a decision to delist Big Mac as a trademarked restaurant name and stop the chain using it on poultry products.

“We objected to them to their use of Big Mac as a restaurant because it is not a restaurant,” said Supermac’s founder, Pat McDonagh. “So what happened today is the European court has delisted it because they hadn’t used the trademark [as Big Mac for a restaurant] … Then the ECJ went a bit further: they said Big Mac can be used as a meat product, a burger, but it can’t be used as a chicken product.”

The ECJ said: “The evidence which was submitted by McDonald’s does not provide any indication of the extent of use of the mark in connection with those goods, in particular as regards to the volume of sales, the length of the period during which the mark was used and the frequency of use.”

McDonagh said: “This is a significant ruling that takes a commonsense approach to the use of trademarks by large multinationals. It represents a significant victory for small businesses throughout the world.

“The original objective of our application to cancel was to shine a light on the use of trademark bullying by this multinational to stifle competition. We have been saying for years that they have been using trademark bullying.”

The ECJ said: “McDonald’s has not proved that the contested mark has been put to genuine use as regards the goods ‘chicken sandwiches’, the goods ‘foods prepared from poultry products’ and the ‘services rendered or associated with operating restaurants and other establishments or facilities engaged in providing food and drink prepared for consumption and for drive-through facilities; preparation of carry-out foods’.”

The intellectual property lawyer Matthew Harris at UK law firm Pinsent Masons described the ruling as “a huge wakeup call” for owners of well-known trademarks that they must, like smaller rivals, evidence use of trademarks or risk losing them.

A statement from McDonald’s said: “The decision by the EU general court does not affect our right to use the ‘BIG MAC’ trademark. The BIG MAC trademark is incredibly strong throughout the world, including in the EU, and this decision will not in any way impact our ability to use or to protect the trademark against infringements.

“McDonald’s has held the EU BIG MAC trademark registration since 1996 and it remains in full force and effect for the iconic sandwich that our fans around the world have come to know and love. In partnership with our franchisees, we’re excited to continue to proudly serve our Big Mac and our local communities, as we have done for decades.”

A spokesperson for McDonald’s said: “The decision by the EU general court does not affect our right to use the ‘Big Mac’ trademark. Our iconic Big Mac is loved by customers all across Europe, and we are excited to continue to proudly serve local communities, as we have done for decades.”