Ubisoft is suing an American disc duplication firm for $10 million after an early version of its PC game, Assassin's Creed, made its way on to the internet.

The publisher has claimed that North Carolina-based Optical Experts Manufacturing is responsible for the leak, which occurred six weeks before the game's official release.

OEM allegedly ignored normal security measures that would have prevented the leak occuring, when an employee took a copy of the game home.

The source of the piracy has already been tracked down to the house of an OEM employee, who is effectively responsible for around 700,000 downloads of the game. Ubisoft, understandably rather ruffled by the situation, has described the leak as "an extraordinary breach of trust and gross negligence".

Even worse for Ubisoft is that the leaked version wasn't even finished, and included a bug for such circumstances which caused the game to crash half way through. Some reviews on the game have reportedly been based on the illegally downloaded version, which has caused confusion and "irreparable harm" to the publisher's reputation, claims Ubisoft.

OEM is being sued for breach of contract, negligence and copyright infringement, with damages and legal fees sought for the three claims to the amount of $10 million.

We reckon the employee responsible is probably rather short of a job right now...