Litigious Atari Corp’s Atari Games Corp subsidiary which develops arcade video games software is suing Nintendo of America Inc and its Japanese parent, Nintendo Co Ltd, claiming that Nintendo has monopolised the US market for video game cartridges for Nintendo’s home entertainment systems: Atari reckons that Nintendo’s practice of building a lock-out system into its game machines and cartridges has precluded competition in cartridge market and that Nintendo controls over 80% of the US market for home video game hardware; it wants an injunction and $30m to $35m of compensatory damages – to be tripled under Sherman anti-trust rules.