Surely this argument could also apply to hardware. A piece of hardware's interface would be its API, which would surely mean that any software written to use th

Surely this argument could also apply to hardware. A piece of hardware's interface would be its API, which would surely mean that any software written to use that interface (drivers) would be a derivative work. Which in the case of proprietary hardware, using non-standard interfaces, would mean that software would need a license from the manufacturer to be distributed.