This is the fourth time in two years that the slot machine maker, International Game Technology, sues its rival, Bally Technologies. All lawsuits were due to patent infringement. This particular time, IGT claims that the Bally Power Bonusing created by Bally Technologies infringes upon several patents registered by IGT in the United States.

IGT is asking the District Court to order the removal of said products. Apparently, the company had warned Bally not to use the system in casinos because it meant an infringement on its patents but they were ignored.

IGT Chairman and Chief Executive Officer TJ Matthews said: "The patents at issue in this lawsuit cover innovations that Bally has chosen to exploit for its own benefit without seeking a license or any other authorization from IGT".

Bally Technologies’ officers made no comments.