Copyleft licensing aims to use the procedure of law to protect user freedom and provide users legal rights and obligations. Say what you will of RMS but you can

Copyleft licensing aims to use the procedure of law to protect user freedom and provide users legal rights and obligations. Say what you will of RMS but you can't easily argue he wasn't being serious when he created copyleft licensing as a means for providing users with legal protections that would be defensible in a court of law.