A legal battle between comics giant Marvel and the estate of famed illustrator and longtime Stan Lee collaborator Jack Kirby is showing no sign of ending.

Kirby’s family claims that Marvel should no longer retain the copyright for the work Kirby, who died in 1994, did on such iconic superheroes as Iron Man, X-Men, the Incredible Hulk and Spider-Man.

Marvel sued, seeking a court to declare that Kirby’s art had been “work for hire” and, as a result, the comicbook maker retained control. At stake are licensing rights and lucrative royalties.

In late November, a New York federal judge ruled in what amounted to a split decision on a counter-suit filed by the Kirby family. The court refused to throw out the Kirby estate’s effort to terminate Marvel’s copyrights.

At the same time, the court did say it would not compel Marvel to pay damages or return artwork that never made it back to Kirby after the comic book company allegedly contracted to do so in the mid-1980s.

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Stan Lee ready to drop the puck | Lee busy with plenty of projects in pipeline | Kirby, Marvel suit lingers on