There is a thread at the Google AdSense Help forums have recent complaints about third-party sites drastically inflating their earnings reports, showing massive spikes in ad impressions on sites they do not control.
This results in the RPM (revenue per impression) dropping and makes AdSense publisher freak that Google might think their site/ad placements are bad. Which might result in Google thinking their earnings per click should go lower because they generate low quality impressions for their ads.
Here is a screen shot of one of the reports from a publisher showing fake data from boxofficemojo.com. That site has said they don’t even serve ads with AdSense, so they can’t remove anything. Some think there is this hack going around where this traffic is being spoofed to AdSense?
One user wrote:
Google is supposedly aware of this issue, says one Google AdSense Top Contributor. He wrote:
Do you have this issue?
Forum discussion at Google AdSense Help & WebmasterWorld.