Microsoft faces a lawsuit over the live tile feature in its Windows 8 and Windows Phone 8 operating systems just days after they were officially unveiled.
The legal challenge has been brought by a US company based in Oregon called SurfCast, which claims it owns patents that cover the technology.
"The SurfCast inventors conceived the Grid & Tile User Interface over 10 years ago," it says on its website.
The filing is just the latest in a seemingly endless battle between IT vendors of all shapes and sizes looking to gain a financial or market advantage by taking rivals to court over claims of patent infringement.
A Microsoft spokesperson said it was confident it would win any case on the patents in question.
"We are confident we will prove to the court that these claims are without merit and that Microsoft has created a unique user experience," they said.
In SurfCast's filing it asks for a ruling forcing Microsoft to pay damages on the alleged patent infringements and to cover its court costs.
The legal challenge comes just days after Microsoft unveiled the operating systems at events in the US. The timing is odd given that the Windows Phone 7 system, which features the same interface, has been on the market for over a year.
It could be that SurfCast was waiting to include Windows 8 within the same lawsuit so as to give its legal attack on Microsoft a higher profile.
Meanwhile, Microsoft has been keen to tout the business benefits of its new Windows 8 and Windows Phone 8 operating systems as it seeks to claw back market share in the tablet and smartphone markets.
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