A 10-page legal complaint alleges that Hall's firing of Marimow - a two-time Pulitzer Prize-winning reporter on his second stint as Inquirer editor - on Monday was "unauthorized, unforeseen and ill-advised."
The dispute is already notable for its high-powered lawyers. The Katz-Lenfest faction is represented by the law firm of Sprague & Sprague and its prominent founder Richard Sprague; the other four owners with a 58 percent in the media company said its legal team includes former U.S. Secretary of Homeland Security Michael Chertoff.
The owners who supported the firing of Marimow - which include South Jersey Democratic power broker George Norcross, one of two members of IGM's management committee along with Katz - have hired a spokesman, Philadelphia political consultant Dan Fee.
Fee issued a statement on the defendants' behalf that accused Katz of interfering in the editorial operations of the Inquirer. It also said Marimow's "shortcomings have been well-documented" in internal documents leaked to Philadelphia media outlets hours after the editor's firing.
The local group of investors - who purchased the Philadelphia newspapers and the website for $55 million in April 2012 - are the fifth ownership group since the end of 2005.
The suit filed on behalf of the Katz and Lenfest entities states that "[m]orale among the Inquirer's staff has plummeted" since Marimow's firing was announced.
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