The 49-year-old actor is known to have left the project after demands of cutting his fees by half, said Hollywood reporter.
With low sales of the movie at Cannes the producers were looking to trim the budget of the film to a USD 60 million range.
The film is based on Boston mob kingpin Whitey Bulger and his close relationship with FBI agent John Connolly.
Actor Joel Edgerton will play the disgraced FBI agent.
Depp will next be seen in "The Lone Ranger" releasing on July 3.