Actually, who knows, do you honestly think they're that sohisticated? I know for sure that one of the ways they trap people is seeding the songs from sites (or running the sites themselves); you can find this out for sure, do a test... Install Peeer Guardian and go download 100 songs. Turn it off, download another 100 songs. Wait 6 months and get a couple letters from your ISP and see what songs you're flagged for...

99% chance, none of the "peer guardian" songs will be listed; the onlyones which should show are "non-peer guardian songs". This is because peer guardian actively blocks known ip ranges, and as such they can't sit and bitch to your isp.
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