400mm F/2.8 OS

New Sigma 400mm F/2.8 OS Patent Emerges, Next Sport Lens?

There are currently only two lenses in Sigma's high performance 'Sports' lineup, the incredible 120-300mm, and the new 150-600mm. If a new patent is any indication, it seem that Sigma may have another Sports lens coming down the pipe in the form of a new 400mm F/2.8 OS.