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:

John Mueller of Google responded:

Here is the video embed:

Hat tip to Glenn Gabe for pulling this nugget out:

Forum discussion at Twitter.