Microsoft scored a victory in federal court yesterday when the US Court of Appeals for the Federal Circuit overturned a $521 million patent-infringement ruling against the company. The ruling was part of an Eolas Technologies and the University of California (UC) case that claimed that Microsoft Internet Explorer (IE) violates a patent on technologies the two organizations developed. The court has vacated the decision and ordered the case to be retried in a lower court. 
  
Much controversy has surrounded the validity of the patent, which led the US Patent and Trademark Office (USPTO) to launch a rare investigation. Last year, the agency released a preliminary decision invalidating the patent but has yet to finalize the decision. The patent revolves around the technology that lets plug-ins such as Adobe Acrobat and Macromedia Flash run inside IE. Microsoft claims the USPTO incorrectly awarded the patent because Eolas and UC didn't invent the technology. During the trial, the company tried to demonstrate to the jury the Viola browser, which used similar technology. Pei-yuan Wei developed the Viola browser in 1993, a year prior to the filing of the Eolas/UC patent. Microsoft had argued that the browser demonstrates "prior art," which means that the technology couldn't be patented. The new ruling states that during the original trial, District Court Judge James Zagel incorrectly ruled that Microsoft couldn't show the browser to the jury. The judge had claimed that Wei had "abandoned, suppressed, or concealed" his browser, which invalidates it as prior art. The appeals court disagreed and cited an example of Wei demonstrating his browser to a group of Sun Microsystems engineers and releasing a new version as proof that Wei didn't abandon the technology.
  
The appeals court also ruled that the lower court was wrong in dismissing Microsoft's claim that Eolas inventor and former UC researcher Mike Doyle misled the USPTO by withholding information about the Viola browser. The lower court dismissed the claim because of its determination that Viola didn't constitute prior art. The reversal gives Microsoft another route to get the patent ruled unenforceable.
  
Microsoft expressed satisfaction with the court's ruling and said it looked forward to the new trial. "Today's reversal gives Microsoft the opportunity to tell the jury the whole story of how this technology was developed and to present evidence that shows that Eolas did not invent this technology, and that it was developed by others, particularly Pei-yuan Wei and his colleagues at O'Reilly and Associates," the company said in a statement.
  
The case continues to be a high-stakes battle for not just Microsoft but for the entire Web community. If Microsoft loses, millions of Web pages would have to be modified to no longer use the plug-in technology. The World Wide Web Consortium (W3C) said the new ruling was a step in the right direction and hoped the patent office will ultimately reject the Eolas/UC patent.