>RBL / BGP blackholes based on bad registration info? That's sort of what the Spamhaus DROP list does. Many (most?) of the entries are ancient abandoned allocations that have been hijacked by crooks.
- Dealing with abuse complaints to non-existent conta... Gabriel Marais
- Re: Dealing with abuse complaints to non-exist... Paul S.
- Re: Dealing with abuse complaints to non-e... goemon
- Re: Dealing with abuse complaints to n... Bill Woodcock
- Re: Dealing with abuse complaints ... David Conrad
- Re: Dealing with abuse compla... goemon
- Re: Dealing with abuse co... Gabriel Marais
- Re: Dealing with abuse co... John Levine
- Re: Dealing with abuse complaints to n... Owen DeLong
- Re: Dealing with abuse complaints ... Mark Andrews
- Re: Dealing with abuse compla... Suresh Ramasubramanian
- RE: Dealing with abuse co... Tony Hain
- Re: Dealing with abus... Suresh Ramasubramanian
- Re: Dealing with abuse complaints to non-exist... Stephen Satchell
- Re: Dealing with abuse complaints to non-exist... John Levine
- Re: Dealing with abuse complaints to non-exist... Jon Lewis
- Re: Dealing with abuse complaints to non-e... Christopher Rogers
- Re: Dealing with abuse complaints to n... Alexander Merniy