The chain, which owns the Empire cinema in London's Leicester Square, was formed in 2005, when Irish entrepreneur Thomas Anderson acquired 18 cinemas put up for sale on the orders of the Office of Fair Trading following mergers between two other cinema groups, Cineworld and UGC, plus Odeon and UCI.
The7Stars is understood to have pitched in tandem with an unknown creative agency approximately seven weeks ago, alongside three other media and creative agency pairings.
Empire has no incumbent creative or media agency. In July, the company appointed Carlton Screen Advertising to handle its cinema advertising sales.
The news comes just a few days after The7Stars was appointed to the media planning and buying account for William Grant's whisky brand Monkey Shoulder. At the beginning of November, the agency won a £1m media account for cosmetics company Space NK.
Founded by former Carat executives Colin Mills and Jenny Biggam, The7Stars is currently one of five agencies shortlisted to bid for record label EMI's £14m media business, currently held by Carat.