[amluto]

I don’t know anything about the legality, but UMRP is very common.

[thaumasiotes]

UMRP has no legal effect. It's just a declaration by the manufacturer that "if we catch you pricing below this point, we will stop selling to you". Once you have the item, you can price it however you want.

[amluto]

But that’s the point: UMRP is not illegal. It gives the manufacturers de facto control of retail pricing.