Tengen
Tengen was a subdivision of Atari that made unlicensed ports of games for the NES
An unlicensed Tengen cartridge Tengen was a subdivision of Atari, developing home console parts of Atari games as well as games by other publishers, such as SEGA or Namco. Tengen released its games without a license by Nintendo and faced lawsuits for doing so. When Time Warner bought Atari Games in 1993, Tengen was shut down.
