Starting on February 19th, Google began phasing out sidebar ads from their search engine results pages. They will now show one to four ads before the organic search results, and the rest will be pushed to the bottom of the page.
SO This only effects Pay Per Click advertisers, because now there is less ad space. No more ads on the right side seems like a waste of space, so who knows what Google is doing here, yet you can bet it has something to do with MOBILE. Google is all Mobile, all the time.
The update – which is described as “global and permanent” will only apply to desktop searches, which may affect the traffic you see from desktop devices. According to Search Engine Journal: “High volume and general search terms have been most severely affected by the update so far. Long-tail and niche terms will begin to see their right hand ads disappear in the coming weeks.” This change hasn’t yet rolled out to mobile, so it remains to be seen if/when that will happen and what the results will be… Search Engine Journal