Blocking specific IP addresses has been a common request for advertisers. It’s mostly requested by companies who know their competitors IP addresses and wish to block those competitors from ever seeing those ads.

For more sophisticated advertisers, it can be used to block IP addresses that send a lot of traffic but don’t convert.

This isn’t as useful as Yahoo’s continent blocking option, where one can decide not to show ads on particular continents, however, it’s a step in the right direction.

We are also going to be releasing the ability to prevent ads from showing to specified IP addresses (see #4) in the next month.

Source: Shumans.com. It’s also a good read on where Google stands on the Click Quality Council requests.