Planet Coaster developer Frontier Developments is suing Atari over alleged millions in unpaid royalties from 2004's RollerCoaster Tycoon 3, TMZ reports.

RollerCoaster Tycoon 3 was developed by Frontier and published by Atari. According to TMZ, Frontier claims that they received only $1.17 million in royalties for the game. Allegedly, sales figures were higher than they thought—about $2.2 million in royalties higher.

To check whether Atari had artificially deflated sales figures, Frontier asked for a sales audit, which they say Atari is dragging its feet on. Atari filed for bankruptcy in 2013.

Advertisement

“We have so far been denied our contractual right to audit by Atari, and we are unfortunately left with no other way to resolve our concerns,” a Frontier representative told Kotaku. They added that Frontier had attempted to resolve the issue without legal action since April, 2016.