Atari is being sued by a video game developer who says its been stiffed $2.2 million in royalties by the video game giant.

Frontier Development claims it's been working with Atari since 2003 when it struck a deal to develop the game RollerCoaster Tycoon 3 and a bunch of others. When Atari went bankrupt in 2013, Frontier says they stuck it out and amended their contract.

Atari's out of the red now. In April, Frontier started to believe it was getting ripped off, claiming another website showed higher sales figures.

Frontier says the site calculated Frontier should've received $3.37 million in royalties from Atari when they only got $1.17 mill. According to Frontier, Atari then delayed when it was asked for an audit of their sales report.

Frontier got fed up and is now suing to get the rest of their dough.