LOS ANGELES — A bitter and long-running legal dispute over the ownership rights to Marvel superheroes like Thor and the X-Men ended on Friday with a settlement between Marvel, which is owned by the Walt Disney Company, and the heirs of the comic book artist Jack Kirby.

Financial details were not disclosed.

With potentially wide-ranging repercussions for both Disney and Hollywood as a whole, the United States Supreme Court had been prepared to consider whether to hear the case in a private conference on Monday.

Marvel said in a statement: “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.” Mr. Kirby died in 1994.

Disney directed calls to a Marvel spokesman, who declined to provide additional comment. A lawyer for the Kirby family, Marc Toberoff, and one of the litigants, Neal Kirby, Mr. Kirby’s son, did not respond to email queries.

Jack Kirby’s four children (Barbara, Lisa, Neal and Susan) had been fighting in court since 2009 — when Disney bought Marvel Entertainment for $4 billion — to reclaim the rights to dozens of characters created or co-created by Mr. Kirby between 1958 and 1963. The characters, which include the Incredible Hulk and Captain America, now underlie valuable movie series, television shows, toy lines and theme park attractions.

Because of long-term licensing agreements made by Marvel before the Disney purchase, a legal victory for the Kirbys would have touched almost every corner of Hollywood, not just Disney. For example, Sony holds long-term movie rights to Spider-Man; 20th Century Fox has the equivalent for the X-Men and Fantastic Four. Universal Studios holds Florida theme park rights to the Hulk and other characters.

The Hollywood guilds and other heirs to the creators of old characters were also watching carefully.

SAG-Aftra, the actors union; the Directors Guild of America; and Writers Guild of America submitted a brief to the Supreme Court in June in favor of granting the Kirbys’ petition. “The implications are much broader” than the Kirby case, the brief said.

The Kirbys based their case on a provision of copyright law that, under certain conditions, allows authors or their heirs to regain ownership of a product after a given number of years.

The United States Court of Appeals for the Second Circuit, in New York, unanimously agreed last year with a lower court’s ruling that the Kirby family could not reclaim the rights because Mr. Kirby’s art and stories had been “works for hire.”