Roy Disney wielded considerable behind-the-scenes influence at Disney
Roy E Disney, a long-time executive of the Walt Disney Company - which his uncle founded - has died aged 79.
He had been ill with stomach cancer for the past year.
Mr Disney, who played a powerful role at the company for more than 50 years, led a successful shareholder revolt against chief executive Michael Eisner.
Disney company president Bob Iger said Roy Disney's commitment to the art of animation was unparalleled and would always remain his personal legacy.
Born on 10 January 1930 in Los Angeles, Mr Disney spent much of his privileged childhood among the people who worked for his family's animation empire.
His uncle Walt and father Roy had founded the company seven years before his birth.
Roy Junior started working for the company in 1953, first as an assistant film editor and later producing and directing a number of television and theatrical productions.
He led two shareholder revolts against company executives with whose strategies he disagreed.
In 1984, he ousted Walt Disney's son-in-law, Ron Miller.
In 2003, Roy E Disney resigned from the board of the company. In his resignation letter, he called for the removal of Disney chairman Michael Eisner, whom he blamed for plummeting profits and low standards.
Mr Eisner managed to hold on to his post for another two years before resigning in 2005.
Disney company president and chief executive Bob Iger paid tribute to Roy E Disney saying his "true passion and focus were preserving and building upon the amazing legacy of Disney animation that was started by his father and uncle."
Roy E Disney died at the Hoag Memorial Hospital Presbyterian in Newport Beach, California.