Tengen was an American video game publisher, best known as Atari Games' console publishing arm, active primarily in the late 1980s and early 1990s. Its catalogue of around 62 titles includes arcade ports and licensed sports games such as Ms. Pac-Man, Rolling Thunder, and R.B.I. Baseball. Tengen's history is closely tied to a notable legal dispute with Nintendo over unlicensed NES cartridge production.