The family of Jack Kirby and Marvel Entertainment have resolved a long-running legal dispute over the rights to some of the most popular characters in Marvel’s library, including “Spider-Man” and “X-Men.”

“Marvel and the family of Jack Kirby have amicably resolved their legal disputes, and are looking forward to advancing their shared goal of honoring Mr. Kirby’s significant role in Marvel’s history,” the litigants announced in a joint statement on Friday.

The family had been seeking Supreme Court review of their appeal of lower court rulings that largely sided with Marvel.

Kirby’s heirs had sought to terminate grants of copyrights to the characters, under a clause of the 1976 Copyright Act, but Marvel contended that they continued to own the characters because Kirby was working “for hire.” The latter is an exception to artists and families who seek to terminate grants of copyrights.

After the Kirby heirs sent out 45 notices in 2009 seeking to terminate the assignment of copyrights in comics featuring works like “The Incredible Hulk,” “The Avengers” and “The Fantastic Four,” Marvel sued, seeking a court determination that Kirby’s work on the characters was “for hire.” The litigation concered a total of 262 works published between 1958 and 1963.

A federal court sided with Marvel in 2011, and an appellate court upheld the determination that Kirby’s work was “for hire.”

The family, represented by Marc Toberoff, had been seeking Supreme Court review, and the high court was set to consider whether to take it at its conference on Monday. Their writ of certiorari had drawn the support of organizations like SAG-AFTRA, which argued that the 2nd Circuit Court of Appeals decision in favor of Marvel created “an onerous, nearly insurmountable presumption that copyright ownership vests in a commissioning party as a work made for hire, rather than in the work’s creator.” Bruce Lehman, former director of the U.S. Patent and Trademark Office, also weighed in in favor of the Kirby heirs, arguing that the law in the late 50s and early 60s was that the definition of a work made “for hire” applied only to traditional employees and not freelancers.

Marvel, however, argued that Kirby’s contributions to the works were made at Marvel’s instance, under the editorial and stylistic direction of its editor at the time, Stan Lee.

If the Supreme Court had taken the case, it would have had tremendous implications not just for Marvel, a unit of the Walt Disney Co., but DC Comics as well, as it put into question the definition of what constituted works made “for hire” during the golden age of comics in the 1950s.