Freshfields Bruckhaus Deringer and Mayer Brown are advising on the sale of the maker of Peppa Pig, Entertainment One, to U.S. toy and board game company Hasbro in a $4bn deal.

The deal comes four years after Entertainment One (E One) took a controlling stake in the TV production company behind Peppa Pig.

Hasbro chairman and chief executive Brian Goldner said in a statement: "The acquisition of E One adds beloved story-led global family brands that deliver strong operating returns to Hasbro's portfolio, and provides a pipeline of new brand creation driven by family-oriented storytelling, which will now include Hasbro's IP."

Mayer Brown is advising longstanding client E One with a team being led by London corporate partners Robert Hamill and Rebecca Bothamley.

The team also includes Brussels-based antitrust partner Julian Ellison, New York-based banking and finance partner Adam Wolk, and corporate partner Kate Ball-Dodd.

According to a person close to the matter, Mayer Brown has advised Entertainment One for more than a decade. The firm advised the company on its 2015 acquisition of 70% of production company Astley Baker Davies – the company behind Peppa Pig – for £140m.

According to Hasbro's statement, it is being advised by Freshfields. A person with knowledge of the matter said the Magic Circle firm's team is being led by London corporate partner Laurie McFadden.

U.S. heavyweight Cravath, Swaine & Moore and Canadian firm Stikeman Elliott are also advising Hasbro, according to the company's statement.