In another recent change of Google’s algorithm, they have released an update that is intended to penalize sites that have excessive ads, particularly above the fold. What does “above the fold” mean? This area is the space on a website that you can see before you have to scroll down on the page. Any immediately visible space is above the fold. This update is basically meant to reward sites that give users a better experience. Google’s theory implies that the less ads a user has to scroll past, the better they will like the site that Google directed them to in the search results.
Most e-commerce and business sites are likely to not be effected by this. Sites that are more likely to be effected are those that are content based and generate their revenue mostly from ads themselves. Hence, why the ads may be displayed more heavily on these types of sites.