"authority" to route?

Hi, Is there a common practice of providers to vet / validate requests to advertise blocks? Who is the "authority" when it comes to determining if a request for routing is valid? Is it the WHOIS data maintained by the various RIR? It seems I'm playing whack-a-mole to get some routes shut down for some blocks I've taken over admin for. If I email the contacts for the AS in WHOIS, and get no response, or a negative response, should I start going to their peers? Some practical advice would be appreciated. -- Jim Mercer Reptilian Research jim@reptiles.org +1 416 410-5633 "He who dies with the most toys is nonetheless dead"