Microsoft and eight games publishers have been sued by an outfit which insists that the Kinect infringes some of its patents. Redmond's Kinect motion tracking system has been a sales success for the firm, and made it pots of cash.

But Impulse Technology is claiming that Microsoft and some of the largest games publishers in the industry are infringing its patents. Impulse said that it informed Microsoft of its patents, most of which are titled "System and method for tracking and assessing movement skills in multidimensional space". The patents were filed as far back as 1999. Patent number 6430997 granted 13 August 2002, describes a system for quantifying physical motion of a player or subject and providing feedback to facilitate training and athletic performance. A preferred system creates an accurate simulation of sport to quantify and train several novel performance constructs by employing: sensing electronics for determining, in essentially real time, the player's three dimensional positional changes in three or more degrees of freedom and computer controlled sport specific cuing that evokes or prompts sport specific responses from the player.

Sounds pretty good to us. But we are sure that it is not what it seems. So far none of these patent rows appear to be about technology which was invented and specifically nicked. The US Patent system is pretty much a joke at the moment, and no one seems that keen to do much to improve it.