The prosecution lawyers in Microsoft's 'Vista Capable' case are considering appealing against a ruling that removed the class-action status from the lawsuit.

The status of the case was changed this week after a US District Court Judge Marsha Pechman said the plaintiffs had failed to show that the 'Vista Capable' campaign had made them pay more for their computers than they would have otherwise. The change to status of the case means Microsoft can only be sued by individuals and not a group of potentially hundreds of customers.

The lawsuit began after a number of PC owners claimed Microsoft defrauded customers by promoting PCs and laptops as 'Vista Capable' when they could only run Windows Vista Home Basic. The plaintiffs have contended that Vista Home Basic is not the 'real' Vista, in large part because it lacks the Aero user interface. Microsoft has denied that it duped consumers, and has countered that Home Basic is a legitimate version of Vista.

"We anticipate further motion practice in the trial court, followed by - if unsuccessful - an appeal to the Ninth Circuit," said Jeffrey Tilden, a partner in the Seattle law firm Gordon Tilden Thomas & Cordell LLP.

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Tilden, as well as Jeffrey Thomas, another partner, declined to get more specific about their plans for the lawsuit. Their firm brought the original lawsuit against Microsoft on behalf of Dianne Kelley, a Washington state resident who bought a PC marked 'Vista Capable' in November 2006, two months before the operating system was released to retail.

Microsoft rolled out the 'Vista Capable' marketing campaign in April 2006 to ensure that PCs equipped with the older Windows XP continued to sell as Vista's release date neared. Computers that bore a Vista Capable sticker could later be upgraded to the new operating system, Microsoft promised.

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Kelley claimed that Microsoft pulled a fast one with Vista Capable, however, because the company let computer makers slap the sticker on PCs that later could run only Vista Home Basic, the least-expensive edition. Her lawyers argued that because Home Basic lacked many of the features Microsoft had trumpeted for Vista, including the Aero graphical user interface, it was not a 'real' version of the operating system.

"Judge Pechman is an incredibly strong trial judge but we respectfully disagree with her here," said Tilden.

The lawsuit is best known as the source for hundreds of insider emails that have been made public by the court. Among the disclosures were ones that showed Microsoft relaxed the requirements of Vista Capable to accommodate Intel, a decision that then enraged Hewlett-Packard, another major partner.

Those emails also revealed the sometimes-fierce arguments within Microsoft over the program, including a recommendation by an internal marketing group that Home Basic be stripped of the name 'Vista' because of concerns over what it called "user product expectations."

Computerworld (US)

See also: Microsoft to pay £8.5bn in 'Vista Capable' case