Activision, the publisher of the popular Guitar Hero games, asked a federal court to declare that its popular game does not violate a patent held by real-guitar maker Gibson Guitar Corp, AP reports. The suit is a reaction to pressure from Gibson which wants Activision to license its patent, covering a virtual-reality device that included a headset with speakers and that simulated participating in a concert.

"We disagree with the applicability of their patent and would like a legal determination on this," George Rose, Activision's general counsel, said in a statement.

Gibson attorney F. Leslie Bessenger alleged in a letter to Activision in January that the video game producer was "taking advantage of Gibson's patented technology without properly compensating Gibson."

Activision announced a month ago that Guitar Hero: Aerosmith will be launching in June for the PS3, Xbox 360 and Wii, which means the successful game will enable its fans to play about 30 Aerosmith songs as well as others from various acts that have opened for the band.

The Guitar Hero franchise is already on its way to become a cultural phenomenon. Even Bill Gates has chosen a Guitar Hero competition to end his CES speech. Research company NPD Group said a month ago that the Guitar Hero franchise has set an industry record, surpassing $1 billion in North American retail sales in just 26 month.

Also, the latest title released by Activision, Guitar Hero III: Legends of Rock was the number 1 title in units and dollars for calendar year 2007. The success of the games was predictable since its launch, as the title earned more than $115 million in its first week on sale only in North America. The game is to be released in Europe.

That third edition of “Guitar Hero” contains 70 rock songs of various artists or bands such as: Disturbed, Slipknot, The Killers, Aerosmith, A.F.I., Guns N’ Roses, Metallica, Muse, Pearl Jam, Rage Against The Machine, Red Hot Chili Peppers, Smashing Pumkins and more others.

Guitar Hero III: Legends of Rock includes a multiplayer action-inspired battle mode, grueling boss battles, a host of exclusive unlockable content and visually stunning rock venues. Expanded online multiplayer game modes allow consumers worldwide to compete head-to-head for true legendary rock status.