We have had a similar problem in the past and, like Joe Hansen, use DFP and partner with OS4. Whenever we get reports of these from users, OS4 tells us they generally do come from the remnant ads running on our site. They then place blocks on the remnants to try and stop the pop-ups.
We last had this issue in early March and I have not gotten any reports recently.
We have had a similar problem in the past and, like Joe Hansen, use DFP and partner with OS4. Whenever we get reports of these from users, OS4 tells us they generally do come from the remnant ads running on our site. They then place blocks on the remnants to try and stop the pop-ups.
We last had this issue in early March and I have not gotten any reports recently.