I've come across a light controlled by three switches. It's unique to me because any combination of switches must be in the "on" position for it to work. All three must be "off" for the light to go off. It's not a typical multipole switch.
I can naively imagine that three normal switches in the same circuit connected to the same light would behave this way but I've never seen this before.
Is this safe? Is it a code violation? What is the appropriate terminology to describe this setup?