Marvel’s “Kirby Week” covers all of this in glowing fashion. But the articles all gloss neatly over the other side of the story: namely, the fact that Marvel fought a decades-long battle to keep Kirby from claiming creative and financial control over his creations, culminating in a legal dustup with his heirs that very nearly landed in front of the Supreme Court. The story of Kirby’s struggle with Marvel is also one of the most public examples of the lengths to which even the greatest of creators had to go in order to get credit—and compensation—for his work.

The origin of Kirby’s battles with Marvel go all the way back to his collaborations with Stan Lee, who, as part of the “Marvel Method,” assigned plot summaries to artists, left while they plotted and penciled the comic, and then wrote dialogue over their work. This was a method born partially of necessity: The overworked Lee wasn’t just Marvel’s primary writer, he was also the main editor with a stable of books to get out. As a result, though, Kirby was often the driving influence behind many of the stories they worked on. (In one oft cited example, Lee told Kirby simply: “Have the Fantastic Four fight God.” Kirby came back with a fully plotted saga of Galactus the World Eater and the Silver Surfer, characters who went on to become major figures in the Marvel Universe.)

As their comics grew incredibly popular, Kirby began to push for recognition for his role in plotting stories and creating characters. He made little headway. Frustrated with his lack of both credit and creative control, and angry at Marvel’s continual refusal to offer him a share of the money his creations were raking in, he eventually left for DC Comics in 1970. As recorded in Sean Howe’s Marvel Comics: The Untold Story, Kirby gave an interview shortly after his departure: “I was never given credit for the writing I did,” he said. “It was my idea to do [The Fantastic Four] the way it was...I had to come up with new ideas to help the strip sell. I was faced with the frustration of having to come up with new ideas and then having them taken from me.”

In the mid-1970s, Congress revised the laws around copyright, offering longer periods of ownership for copyright holders—if the proper paperwork could be provided. Marvel realized that many of its previous contracts were legally questionable, remnants of the comics industry’s fly-by-night origins with regards to creative work. In 1978, the company began handing out freelancer contracts that guaranteed the company “forever all rights of any kind and nature in and to the work.” As Michael Dean wrote in a 2002 issue of The Comics Journal, these “work for hire” contracts were partly a result of the superhero boom Kirby himself had a hand in creating. “It wasn’t just monthly comic books that were at stake any more,” Dean wrote. “It was the vast ancillary potential of licensing and merchandising the content of those comics.” The contracts legally formalized what had previously been loosely assumed to be corporate policy, but having it in writing gave many comics freelancers pause for thought. When Kirby got the contract, he refused to sign it and left Marvel for good.