You're acting like this is a new practice and that adelphia is the first one to do it. Large ISPs routinely blackhole large supernets (/20s and larger) to prevent unscrupulous activity from known offenders who dont clean up their dirty fucking networks.

BMF

Boo Yah!

Earthlink has been known to block hosts who allow phishing for the last few years.

While this may be new to National Net, the problem of ISPs blocking entire hosts for abuse is nothing new.