While poking around the AdSense support site, I came across a page “How am I paid for CPM ads”. Now, it is rare I find any juicy tidbits just in their Q&A style support pages, but this was one of those rare occassions.
Many publishers have believed that AdSense CPM ads – where publishers are paid per impression rather than per click – would result in the same impression earnings regardless of placement. And this has often been evidenced by many sites adding back image-only banners and skyscrapers in low-CTR areas of a webpage, such as the footer and right hand column, while still utilizing text-only ad units in the premium ad placement spots. While not all CPM ads are text-only, many of them are, hence the decision by publishers to use image only ad units in low-CTR placements, hoping to boost up income with impression earnings.
However, this section on the “How am I paid for CPM ads?” seems to call into question this practice, or at least for those publishers hoping to earn full amounts from these impressions.
Please note that the placement of CPM ads on your pages can affect the amount an advertiser pays for that impression. Placing your CPM ad units below the fold, or in an otherwise low-impact location, may result in lower earnings than if the ad unit was placed in a conspicuous location.
So this raises some interesting questions. With the use of external CSS, would the mediapartners bot necessarily know how prominent the placement showing CPM ads happens to be?
Some possible ways they could be determining this:
- Flagging accounts showing more than X amount of impressions with quality checkers checking ad placement for those ad units, and determining if that placement is worth the full value of the impression earnings, or only a percent of it.
- Scale impression earnings based upon what the actual CTR ad is on the ad unit, working off the assumption that higher CTR likely is the result of a more prominent ad placement.
Sounds suspiciously like CPM impression ads version of smart pricing.
Here is how CPM ads are currently displayed on publisher sites:
Because CPM ads compete against CPC ads in the AdWords auction, we’ll always choose the highest-performing ad for your page. If an advertiser wants to specifically target your site, they will need to bid high enough to beat out the CPC ads that are already in the auction in order to show up on your page.
Let’s hope that it takes into account CPM smart pricing when determining the highest-performing ad.