Warner Bros. Discovery has been sued over the rights to Superman in a lawsuit seeking to block the release of the studios tentpole film in several countries ahead of its July debut.

The estate of Joseph Shuster, the co-creator of Superman, alleges that WBD lost its international rights to the character and story years ago but continued to exploit them without its permission or compensation. In a complaint filed in New York federal court on Friday, it seeks a share of profits from all works attributable to the alleged copyright infringement including Zack Snyders Justice League, Black Adam and Shazam! in key countries such as Canada, the U.K. and Australia. In a statement, a WBD said, We fundamentally disagree with the merits of the lawsuit, and will vigorously defend our rights.

The legal action marks a potential hitch in WBDs rollout of Superman, which arrives July 11 as the first solo movie for the character in more than a decade since Man of Steel. Its intended to serve as the cornerstone property for DC Studios co-chiefs James Gunn and Peter Safran, whove planned a slate of projects around the movie and were hired by WBD chief executive David Zaslav with a mandate to reinvent the DC universe.

DCs ownership of Superman dates back to 1938, when writer Jerome Siegal and Shuster, a graphic artist, sold their rights to the character and story for $130. The heros first appearance under DCs banner was in Action Comics No. 1, which detailed his backstory, secret identity as newspaper reporter Clark Kent, and powers of super strength and speed (his first time flying came in 1943 in Action Comics No. 65).

Since then, its frequently been the target of litigation, starting in 1947 when the duo sued to invalidate DCs ownership of the rights to Superman. The case settled, with a $94,000 payout to Shuster and Siegel to resolve the case.

Under U.S. copyright law, Shuster would typically be able to reclaim his domestic rights to Superman under a provision in intellectual property law that allows authors to claw back ownership of their works after a certain period of time. But his sister and brother reached a deal with DC in 1992 that terminated that right in exchange for $25,000 per year. A federal appeals court later upheld that determination.

This time, Shusters estate looks to take advantage of U.K. copyright law, which automatically terminates copyright assignments 25 years after an authors death. By its thinking, it reclaimed the rights to Superman in 2017 since the graphic artist died in 1992.

Also at play: the possibility that Shusters sister didnt have the authority to bind the estate to the agreement that purportedly surrendered its right to terminate DCs ownership of Superman. In that case, the court stated that the issue is a complex one and punted on deciding it.

The lawsuit claims infringement of copyright laws in the U.K. Australia, Canada and Ireland. It seeks a court order barring further exploitation of the international rights to Superman allegedly owned by the Shuster estate, which is represented by powerhouse copyright termination lawyer Marc Toberoff.