Technically, you do have to prove an invention to be “useful” … and the USPTO examiner can require demonstration. This should happen in a case where the descri

Technically, you do have to prove an invention to be “useful” … and the USPTO examiner can require demonstration. This should happen in a case where the described invention breaks fundamental laws of physics. When briefly digging into the selected prior art (the Google Patents link), it’s not clear to me, non-physist, that the invention really describes a magical perpetual motion device, there are statements such as “requires flowing water source”