Google AdWords Says You Can Be Charged For Invalid Clicks When..
So it is technically possible for this scenario to happen. IP exclusion is query-based, and IPs can actually change as a user browses, so it could happen that a user searches with an IP that isn't excluded, they see the ad, their IP changes to an excluded IP, then they click on the ad.I don't expect this scenario to happen a lot. More often than not, there are issues with how your weblogs are reporting clicks if they're showing clicks from a lot of excluded IP addresses. All that said, are you see a lot of clicks from these excluded IPs?