A Delaware judge has ruled that a lawsuit challenging the appointment of Robert Iger to CEO of The Walt Disney Co. will go forward and begin in August, said Roy Disney and Stanley Gold, dissident shareholders who filed the claim against the media giant.

The ruling, which Mr. Disney and Mr. Gold announced, rejected a request by Disney officials that the suit be dismissed.

Mr. Disney and Mr. Gold in May filed a lawsuit against Disney and its directors alleging that the process by which Mr. Iger was selected to replace outgoing chief executive Michael Eisner was not above board. Among the claims made was that Disney’s board did not conduct an executive search with an open mind and that the board effectively settled on Mr. Iger early on in the process and were simply going through the motions without giving “full consideration” to external candidates.

The dissident shareholders have asked the court to void the 2005 election of Disney’s board and to order Disney to hold another election for directors only after the company has disclosed completely how it selected Mr. Iger, who is expected to assume the CEO title in October.

The suit is part of an ongoing battle between Disney and Mr. Disney and Mr. Gold, who last year played a key role in removing Mr. Eisner as chairman amid years of weak performance.

Since then, however, Disney has been on an upswing, posting strong profit gains and staging a significant ratings comeback at its ABC television network.