Proxy battles are old hat for Mr. Peltz. He has waged successful ones against Procter & Gamble and Heinz. He lost one against DuPont. Disney has not faced a sustained shareholder battle since 2004, when Roy E. Disney, a nephew of Walt Disney, led a successful drive to oust Michael D. Eisner as Disney's chief executive. Notably, Mr. Peltz has an ally on the inside of Disney: Ike Perlmutter, 80, the irascible chairman of Marvel Entertainment and a significant Disney shareholder in his own right. Mr. Peltz and Mr. Perlmutter are longtime friends. In a separate filing on Tuesday, Disney said that Mr. Perlmutter contacted Disney board members and senior executives six times between August and November to push for Mr. Peltz to join the board.