"Konami's actions are extremely surprising," an MTV spokesperson told to MTV News "Successful products such as 'Rock Band' can often become targets for baseless litigation. We have substantial defenses to this claim and intend to vigorously defend it."

In the lawsuit filed yesterday, Konami accused Rock Band of infringing on its patents for a "musical-rhythm matching game" and attempted to block sales of the game. The accompanying documentation included drawings of players using a guitar-shaped controller--a likely reference to Konami's series of Guitar Freaks games.

Prior to the debut of Rock Band last fall, Harmonix was responsible for the creation of the Guitar Hero series and worked with Konami on the Karaoke Revolution series. Konami is currently planning to release a Rock Band-esque title, Rock Revolution, on (PS3, 360, Wii, DS) this fall.