Whats with this trend with sites having auto playing videos below the fold and hidden away? Almost every news site does it now. Worst is when they have a flash ad on top so all you see is the click to play overlay trying to figure out where the video is. AHHH!
As someone working in adtech, some of the megabytes of JS you get sent involves viewability tracking to catch stuff like this. Sometimes you'll even have two or more copies, one from the advertiser and some from the companies in between.
No major advertiser actually trusts what publishers claim - even the big ones like FB and YouTube though they are much less likely to be actively gaming you. That's why there's a lot of tracking JS in pages for viewability to catch stuff like this.
It's called "outstream" video ads. (instream would be a pre-roll where it plays over another video you are wanting to watch)
The publisher has not control over this and probably doesn't realize it's happening, it's purely the 3rd party ad provider they are using that is controlling that.
There are standards in which most ad companies follow (user must be 25% in view, ads must be muted...etc), but recently a large number of Israeli based ad firms have begun running outstream ads without these standards. The purpose is to drive up the view and completion rates. This gives them access to larger media buyers and higher fill rates (filling video ads for every page load is very hard to achieve)
Reference: years of being in the video ad industry
