The entertainment giant is expected to part company with Mindshare when the contract between the two expires at the end of the year.
The business is likely to be contested by Starcom, Disney's agency in the US, and Carat, which handles its account in Europe.
Mark McCraith, the head of client leadership at Mindshare, which has held the business for 11 years, said: "We are proud of what we have achieved together."