dstiles - 8:18 pm on May 25, 2012 (gmt 0)
188.8.131.52 - not just any server farm. Although only blocked by me in January this year my notes say "listed in uce-protect Level 2 as banned (ie for spam) - robtex claims RU, DNS claims CH and registration address is PA (Panama)". There is no rDNS for the specific IP, unusual for a server farm.
I have the complete 184.108.40.206/20 blocked for the above reasons. It looks very dodgy to me.
Verizon is such a large range (220.127.116.11-18.104.22.168) that anything could happen there - and frequently does. Haven't had so many this year but last year over 50 IPs blocked within that range, some for multiple offences. In all I have blocked around 450 verizon IPs over the past couple of years. Not as bad as Comcast (990) but still nasty.