A California appeals court ruled on 4 November that Warner Bros. Television must continue to face a lawsuit over whether its hospital drama The Pitt was derived from ER. The unanimous ruling allows the contract claims to proceed and leaves the question of whether Warner Bros. breached the agreement for later proceedings.

The dispute centres on a 1994 agreement with ER creator Michael Crichton. A provision known as “frozen rights” required agreement from Crichton, Amblin and Warner Bros. before certain projects based on ER could go ahead. The company that now holds Crichton’s contractual rights, controlled by his widow Sherri Crichton, alleges that The Pitt grew out of a proposed ER reboot she declined to approve.

Warner Bros. argued that The Pitt was a new drama with different characters and settings. In reviewing the pilots, the judges pointed to similarities beyond the hospital setting, including the pace, overlapping emergencies and rapid-fire medical jargon. “We find the details here suffice for a prima facie case,” the panel wrote. That means the plaintiff presented enough to keep the case going at this stage.

The panel reached a different conclusion on the claims against the other defendants, including Noah Wyle, John Wells and R. Scott Gemmill. It reversed the lower court’s decision to let those claims proceed. The remaining dispute concerns Warner Bros. Television’s obligations under the original ER agreement.