The New York Times is reporting (no registration required) that the heirs of Jack Kirby have sent notices of Copyright Termination to Marvel, 20th Century Fox, Sony Pictures, Universal Pictures and others to regain the rights to various characters Kirby created or helped create, including The Incredible Hulk, The Fantastic Four, The X-Men, Spider-Man, Iron Man and The Avengers (or those members of the roster that Kirby drew).

Frankly, in my analysis (note: I’m not a copyright attorney), even if Kirby’s heirs win (which is not entirely unlikely, considering the success Jerome Siegel’s heirs have had in reclaiming the rights to Superman), ultimately this will probably just lead to the Siegel estate getting royalty payments off of Marvel comics that use characters created by Kirby, as well as films using the characters he created. It’s very unlikely that Marvel would lose the rights to the characters (particularly since Kirby was not the sole creator).