A Massachusetts judge said he will continue to hear a lawsuit over Viacom Inc. Chief Executive Philippe Dauman’s removal from billionaire Sumner Redstone’s family trust.

The ruling by Probate Judge George Phelan in Canton is a victory for Dauman in his fight against Redstone and daughter Shari, who he claims is manipulating her 93-year-old father to gain control of companies including Viacom, the parent of Paramount Pictures, and CBS Corp.

Dauman and Viacom director George Abrams sued in Massachusetts in May claiming Redstone was mentally incapacitated when he made the decision to remove them from his National Amusements Trust, which controls 80 percent of Viacom shares. The months-long drama has unsettled staff and delayed deals and left many questioning what’s next for the company.

The fight has led to lawsuits in three states, with Redstone suing in California and Delaware to confirm his decision to remove the men and others from the trust and Viacom’s board.

Phelan denied a request for an immediate mental exam of the 93-year-old billionaire.