The Court of Appeal in London recently ruled that "making a computer program which would emulate another computer program but without copying the program code did not constitute an infringement of copyright in the other program or in its preparatory design material."Nothing to stop anyone emulating Flight Simulator and offering a better product than Microsoft.

But since FS is a fairly open program it has been happening for many years already. ;)

Like "Flight Gear" http://www.flightgear.org/and "X Plane" http://www.x-plane.com/ ?Yes, there are points where each is superior or inferior to Microsoft's simulator."...did not constitute an infringement of copyright..."But does the ruling apply to patents?Might only apply to the UK too.There would probably also be issues of aircraft and instrument manufacturer's licensing instrument faces, cockpit MFD graphics, panel designs and airframe shapes. Remember the "not quite right" aircraft names in Fly II?