No, you are wrong. Indeed, your quote of wikipedia says nothing about UNIX being a commercial version o Linux. It says "unix-like". In fact, Linux means "Linux is not Unix". UNIX is not really an operating system: It could better be understood as a set of tools which names, options and behaviours must be respected in order for an Operating System being called of Unix flavour. Solaris is a Unix flavour, BSD is a Unix flavour, MacOS X is a Unix flavour, SCO is/was a Unix flavour. Linux+GNU tools is not a Unix flavour, as it has never been certified as so. It's more of an "emulator" that tries to be compliant to Unix but without being Unix.