The patent is owned by the University of California and licensed by tiny tech firm Eolas Technologies, both of which sued Microsoft for infringement in 1999. In 2003, a jury agreed with the claim and awarded damages of $520.6 million plus interest.
Microsoft appealed and, in March this year, it won a retrial. The case has been sent back to the District Court, where Microsoft effectively has to show that the Eolas patent is invalid because the technology behind the patent was already in the public domain.
Its case will be made more difficult by a September ruling from the US Patent and Trademark Office that found the patent to be valid.
In the meantime, Microsoft has been seeking to appeal a further aspect of the original ruling – that the damages awarded to Eolas and the University of California can cover not only US-distributed copies of Internet Explorer, but also those distributed throughout the rest of the world.
Microsoft argued that this is not fair, as the patent is only a US patent, and therefore not effective beyond the US. It sought a reduction in the sum of damages awarded to reflect this. If successful, reports suggest that Microsoft may have reduced the damages award by around $360 million.
However, the US Supreme Court yesterday refused to consider the appeal, meaning attention will remain focused on the Chicago District Court retrial.
