Activision has slammed guitar maker Gibson over its Guitar Hero lawsuit targeting the video game publisher and several US retailers.
Gibson claims in the suit that Guitar Hero violates a patent registered in 1999 for a platform that "simulates a musical performance".
The federal lawsuit filed last week names US retailers Toys R Us, Wal-Mart, Target, Kmart, GameStop and Amazon, and follows a similar suit against Activision earlier this month.
"Activision continues to believe that Gibson's claims are disingenuous and lack any justification," the company said in an official statement.
"Gibson's lawsuit is a transparent end run around an impartial court that Activision asked on 11 March to rule on patent assertions that Gibson knows have no merit."
Activision maintained that its Guitar Hero retail partners "have done nothing wrong" and that it will actively tackle any efforts by Gibson to "wrongfully interfere with Activision's relationship with its customers and its consumers".
The publisher also claimed that Gibson waited three years to make its patent allegations, and only did so after it became clear that Activision was not interested in renewing its marketing and support agreement with Gibson.
Activision announced this week that it is releasing Guitar Hero: On Tour, a portable version of the game for the Nintendo DS handheld console.
The game will include a diverse set list of master tracks, including classic rock, alternative and pop favourites from bands such as Nirvana, OK Go and No Doubt.
The game will be packaged with a new Guitar Grip peripheral that fits snugly into the DS and a specially designed Guitar Hero pick-stylus to help maintain the guitar-playing appeal of the game while remaining portable.
Guitar Hero: On Tour is being developed by Vicarious Visions and is scheduled for release this summer.
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