netmeg - 12:44 pm on Sep 20, 2012 (gmt 0)
AdTrafficQuality is from Google.
Yes, AdWords advertisers can exclude sites from displaying their ads if they don't like the quality of the traffic or don't have a good history with them - I do this all the time myself.
If I were worried about invalid clicks, I would start trying to nail it down the minute I noticed a big CTR jump, or traffic from another location or anything out of the ordinary. Unusual numbers of claw-backs on the earnings. When one of my sites got hit by a weird bot attack last February, I had AdSense off within the hour, and I kept it off until the attack stopped (several months later) even though, as far as I could tell, the bots weren't clicking. Because the advertisers are always protected first. That's one of the tradeoffs you live with in exchange for an extremely easy-to-implement ad system that pays reliably and usually more than other ad networks.