Warner Bros. has filed another round of motions in its increasingly nasty legal battle with the families of Superman's creators, and their attorney Marc Toberoff.

The studio sued Toberoff in May in a move designed to force him to resign as the lawyer for the heirs of Jerry Siegel, who in 2008 successfully terminated the original 1938 transfer of copyright for Action Comics #1. The 65-page complaint accused Toberoff of manipulating the Siegel family and the estate of Joe Shuster into rejecting “mutually beneficial” longtime agreements with DC Comics, and making arrangements that would give him "a controlling financial interest in the families’ collective claims." Toberoff responded by accusing Warner Bros. of conducting "a smear campaign," and in August filed motions to dismiss, citing California laws designed to curb lawsuits intended to intimidate the opposition through delays and legal expense.

Now, The Hollywood Reporter's THR, Esq. blog reports, Warner Bros. has filed five separate motions in an effort to keep its lawsuit alive. The studio, represented by Dan Petrocelli -- he successfully defended The Walt Disney Co. in a lengthy battle over merchandising royalties from Winnie-the-Pooh -- and a team from O'Melveny & Myers, claims Toberoff is attempting to shield himself from liability for interfering with his clients' contracts.

A hearing is scheduled for Oct. 18.