About a month ago, Google announced the new mobile interstitial penalty, which will be coming to a Google penalty box on January 10, 2017.
Dawn Anderson asked Google's John Mueller if this penalty can be triggered not just based on web page load but also based on when a user scrolls and then on scroll the interstitial comes up. John said, yes it can.
If you implement a popup interstitial ad on mobile that blocks the content and it is triggered as the user scrolls down the page, you can be impacted by this penalty when it goes live.
At the 73:05 mark into the video, Dawn asked:
So if somebody had an interstitial and it only triggered on scroll, for instance, would not be considered an interstitial that they would be penalized on?
Or would the fact that somebody had engaged their content-- I know they probably don't want to just see a big massive sign it says, opt into my newsletter or whatever. How would that be treated? Because obviously--
John Mueller of Google responded:
It could be, yeah.
That could be problematic as well. So that's something where if you're essentially blocking the content from being read by users, then that's something that we would consider a problematic.
Here is the video embed:
Hat tip to Glenn Gabe for pulling this nugget out:
Forum discussion at Twitter.