The move follows Omnicom’s launch of We Are Unlimited, its dedicated agency for its McDonald’s business in the US, in November this year.

According to a report in Mediapost, the lawsuit was filed in the US District Court in New York, with the plaintiffs including UK-based marketing communications group Creston and associated New York firms Cooney Waters and The Corkery Group. 

Creston formed its new agency brand Creston Unlimited in 2014 so that its insight companies such as ICM were rebrand with the Unlimited suffix.

Barrie Brien (pictured), group chief executive, Creston said: “On the 17th November 2016 Omnicom launched an agency called We Are Unlimited, dedicated to serving its McDonald’s client. The Chicago-based agency is referred to throughout the press as ‘Unlimited’. 

“Having rebranded the Creston network as Unlimited in February 2014, and with the UK trademark for ‘Unlimited’, we have significant investment in the brand and are keen to avoid confusion in the marketplace.

There will be no further comment until the matter is resolved.”