Animators and visual effects technicians who worked on the first film claim the producers are using their work for upcoming sequels without obtaining proper rights and giving compensation.

Five animators and VFX specialists who created some visual elements for the cult “Nazis on the Moon” film Iron Sky, have filed suit against the film's producers, claiming copyright infringement of their work.

In a copy of the suit obtained by The Hollywood Reporter, the five claimants accuse Finnish producers Blind Spot and the Iron Sky Universe, the group that handles rights to the Iron Sky brand, of using design elements they created without obtaining the proper rights and without giving proper compensation. The plaintiffs claim their creative contribution to the Iron Sky franchise is such that they should also be considered as joint copyright holders of the original movie.

Iron Sky producer Tero Kaukomaa, in an email exchange with THR, declined to comment on the suit, saying he had not yet seen it, but called the claims erroneous and groundless. He pointed to numerous similar, and unsuccessful, attempts by the lead plaintiff in the case, Trevor Baylis, to claim copyright for his work done on Iron Sky. Kaukomaa described Baylis as a trainee on the VFX team during the first Iron Sky film, who “performed technical duties related to 3D modeling” and could not be considered a creator of the film in any way.

At issue are numerous visual elements designed by the plaintiffs for the first Iron Sky film, which was released in 2012, including the design of various spaceships used in the film as well as background environments. According to the plaintiffs, they granted approval of use of their designs for a single film only but, they claim, Blind Spot and Iron Sky Universe have continued to use elements of their design on the upcoming sequel, Iron Sky: The Coming Race, as well as in a spinoff products based on the first film, including an online video game.

Iron Sky: The Coming Race is set for a February 2018 release. At the Berlin Film Festival this year, Iron Sky producer Tero Kaukomaa also announced plans for an Iron Sky prequel, Iron Sky: The Ark, to be set in China and produced together with Max Wang, producer of Jean-Jacques Annaud’s Wolf Totem, which grossed over $110 million at the Chinese box office. Iron Sky: The Ark film is not included in the copyright suit.