Eolas is a company founded by Dr Michael David Doyle of the University of California San Francisco (UCSF) which came up with a method of allowing browsers to use other small pieces of software. Eolas says that Microsoft turned down the opportunity to licence its technology and when similar technology turned up in Microsoft's browser, Eolas sued.
Microsoft did violate an Eolas patent with its market leading internet browser Internet Explorer, according to an August 2003 judgment in an Illinois court. The court awarded $521m in damages to Eolas.
The patent involved is number 5,838,906, 'Distributed hypermedia method for automatically invoking external application providing interaction and display of embedded objects within a hypermedia document,' filed 1994 and granted in November 1998.
The patent relates to Doyle's claim to have invented the first browser that integrated plug-ins, small pieces of software which enhance the browser's capabilities. Demonstrations were said to have been taking place since 1993.
Microsoft was offered a licence for the technology in 1994 and declined, leading to the 1999 suit over capabilities in Internet Explorer. Microsoft appealed the judgment but The Supreme Court in the US refused to hear the appeal, meaning that the Federal Circuit Court of Appeals judgment still held, though only in relation to foreign sales of Microsoft's Explorer-containing operating system, Windows. The original District Court judgment had ruled that any payments should take account of foreign sales of Explorer.
Microsoft was previously denied the chance to have a new judge hear its case, but the CAFC has now overturned that ruling. The court said that Microsoft was only following what it viewed as correct procedure, and was not seeking to address a perceived bias.
"Microsoft did not assert any bias or misconduct on the part of the original judge," said the ruling, "but instead urged that reassignment should occur automatically [in such a case]".