If you don't know who these companies are, they are the ones harvesting IP addresses of people on p2p networks (and elsewhere) and sending C&D letters to their ISPs.

I recently read somewhere that they correspond to the following chunks of the net:

rangerinc.com: 216.122.0.0 - 216.122.255.255
cyveillance.com: 63.64.0.0 - 63.127.255.255
mediaforce.com: 65.192.0.0 - 65.223.255.255

Every since I've been keeping an eye on how they interact with my computers. My Apache web server logs filled with hits from addresses in these ranges connecting to the GWebCache script the Gnucleus uses to find new hosts. So I decided to block and log them at a firewall level and the logs just keep on growing.

Can someone confirm that noone that is not affiliated with these companies is within these ranges? I've noticed that PayPal buttons aren't showing up and I'm not getting as many third party cookies as I did before blocking them, but I'd hate to be shutting out "legit" file sharers.