Snapchat advertisers are concerned about paying for in-app video ads that go unseen by users, according to Digiday.

Snapchat charges advertisers $0.02 per view – the full-screen videos dont play automatically, so this is essentially charged based on a per-click basis. However, there isnt a minimum play time for the videos, leading to advertisers paying for “zero-second video views”.

According to Digidays sources, this took some buyers by surprise. “The brands didn’t even realize this was happening,” said one source. “It’s all fairly new, and everyone’s just starting to recognize what’s going on.”

The recommended IAB standard for video ad viewability states that 50 per cent of the video– which isnt an issue here, because all Snapchat ads use a full-screen interstitial format. However, the ads fail to meet the requirement that ads must be visible for at least two seconds to be considered viewable. To find out more about the wider issue of viewability, check out our Big Issue feature here.

While Snapchat hasnt responded officially, Digiday cites a source close to the company who claims that its pricing takes skip rates into account, and doesnt charge for any ads which are skipped before they load.