Redstone seeks to oust Viacom directors and CEO from board
Viacom chairman Sumner Redstone is seeking to remove the firm's chief executive Philippe Dauman and four other directors from the Viacom board.
The move is part of an acrimonious battle for control of the media empire that includes Paramount and MTV.
Independent director Frederic Salerno has contested the move, and Mr Dauman remains chief executive.
Mr Redstone's cinema chain, National Amusements, has filed with a Delaware court to approve the changes.
The health of the 93-year-old Mr Redstone and his daughter Shari's influence over him have been questioned.
Mr Salerno said he was filing a countersuit.
In May, Mr Dauman and board member George Abrams were removed as directors of National Amusements.
Mr Dauman then filed a lawsuit on behalf of himself and Mr Abrams against Shari Redstone, claiming she had manipulated her father to gain more control of the board.
Ms Redstone said at the time that it was "absurd" to say she controlled her father.