After winning a $140 million patent infringement suit against Microsoft, Z4 Technologies filed another similar suit against the software giant, this time alleging that Windows Vista and Office 2007 infringes on more of its patents. Z4 says it notified Microsoft of the infringement in December 2006 but that the company has not remedied the infringement.

Microsoft was found to have infringed on Z4's product activation patents in April 2006, a decision that was upheld by a federal appeals court last month. (Z4 also sued Autodesk for the same infringements and won that case as well.) Microsoft's $140 million loss included a $115 million award plus an additional $25 million in damages because the software giant continued to willfully infringe on the Z4 patents and hide its actions.

While the previous suit focuses on earlier Windows versions, Z4's new suit alleges that Microsoft has made only "insignificant" changes to its product activation features in Vista and Office 2007. Microsoft says it is reviewing the new suit and contends that neither Vista nor Office 2007 infringe on Z4's patents. Both products include product activation technology, which is aimed at lowering software piracy.