I've noticed that Best Buy in general is our biggest culprit. We have trouble tickets for them EVERY single day of the week. Sometimes multiple tickets a day. So I think they are dropping cookies on their end.

Then the next biggest trend I see are the people who get them for other networks but not for the ones that we run through Commission Junction. That has to be a setting issue somewhere.

I'll run some stats later this week but I think we are still getting credits for over half that we submit the disputes on. So it's definitely worth submitting them.