Google to charge advertisers viewed for seen ads

More than half of all ads bought online are not seen by anyone

Google announced Thursday that it will only charge advertisers for ads that have been seen by users.

More than half of all ads bought online are not seen by anyone, because they appear too far down the page, or for other factors.

Google says an ad is considered "viewed" only if 50% or more of it is visible for more than one second on the page.

It is the first major digital ad network to announce such a move.

"Even the jingliest, jolliest ad of the season can't work its magic unless it gets seen," wrote Google in a blog post announcing the change.

"Today, we're taking an important step towards this goal by making it possible to buy based on viewability — in real time — across the more than two million sites in the Google Display Network...

"In other words, you can now choose to pay for only those impressions where your ad has a chance to be seen."

Digital analysis firm eMarketer says Google accounted for 32.84% of all digital ad spending worldwide in 2013.

That translates to more than $38bn of the estimated $117.6bn global digital advertising market.