Marc Toberoff, attorney for the heirs of Superman creators Siegel and Shuster, has filed a 43-page petition requesting a reconsideration of the 2-1 decision against the heirs at the 9th Circuit Court of Appeals, according to Deadline.  That decision reaffirmed an earlier ruling against the heirs at the District Court level (see "Superman Creators Lose on Appeal"). 

Toberoff’s petition asked for a reconsideration by the panel or a rehearing by the full court, arguing that the ruling "contravenes Congress’ clear objectives, and this Court’s carefully circumscribed decisions."

If the request for a rehearing is turned down, the last option on this case would be to appeal to the Supreme Court.