I just got the corporate bill today, and 6 of our 40 lines were hit with a third party charge, $ 9.99 each, and all from different companies.  I went online, placed the charges in dispute, then called AT&T billing.  They refunded all of the charges, including taxes, and then offered to put block on all 40 lines to prevent it from happening again.

While the call took a while for all the lines to get blocked, it wasn't that bad.  AT&T should still evaluate the benefit of doing business with these scammers, if not for the customer satisfaction issues even the cost of tying up a rep with me for that long.

Just for fun, we did call the third-party, who claimed they "helped people manage their cellular phone service", but could not explain how to use their service.  The nice, if not frustrated, lady said that she could only take a message or cancel the service, not actually provide any service.  At least she has a job in this economy.