It means that each company collecting on the debt can report it, as long as that tradeline is complete and accurate. Technically, that same trade can be listed an unlimited amount of times on your report. This is one of the loopholes in the system that is designed to make more money for the bank.

Think about this: the worse everyone's credit is, the more banks make in interest and fees. It is in the best interest of the banks and the credit reporting agencies to make everyone's credit as poor as possible.