Freaks, Guitar Hero, Rock Band, and Dance Dance Revolution), however because its concept is very basic and that prior non-patented MIDI drumsets have been used as training tools and as input, the patent's validity has been called into question. Outside of the United States, Devecka's patents have been successfully challenged due to these claims. Neither Devecka nor MTV, for example, have challenged Konami or other music game companies (such as Harmonix for its Rock Band series or Namco for its Taiko no Tatsujin drumming game). Within the United States, Devecka Enterprises has attempted to bar the legal licensing of DrumMania, a competitive and similar product that is more in line with traditional arcade games due to its ability to assign a score for player performance. Devecka's claim relies on its holding of the drum simulation game patent in the United States. Devecka Enterprises president, John Devecka, is a consultant for Red Octane and Activision which now owns all of Devecka Enterprises' US and international patents and produces the Guitar Hero series. All patents issued by the USPTO are presumed valid. Later Devecka patents include: (April 14, 1998) - Method and apparatus for simulating a jam session and instructing a user in how to play the drums (January 25, 2000) - Method and apparatus for simulating a jam session and instructing a user in how to play the drums References External links Maxim Magazine review of Drumscape Drums Drumming video games Music video games