Google has added a feature to their display network advertising. The buzzword here is “Viewability.” When bidding on impressions (CPM) in the display network, you can now require that the ad is viewable before you’re charged for it. The qualifications for an ad to viewable is that at least 50% of the ad is on the user’s screen for at least 1 second. This is in an effort to prevent advertisers from being charged for ads that are below the fold on the publishers page. This isn’t especially applicable to us, since we currently bid on clicks, and in remarketing clicks are more important than impressions.