[sli]

The telecos are basically hamstrung, they cannot legally refuse to route calls so far as I know. I'm not sure that allowing that is the best route, either. That's a whole set of neutrality concerns that we don't need.

They should absolutely be doing something to stop spoofing, though.

[tomschlick]

They can however refuse to do business with people call spoofing using sip trunks. They can see the real phone # and should be able to compare it to the allocated numbers and reject the rest. If a reseller is allowing it to happen then they should cut off the reseller until they get their shit in order.