“Purchased” and “assigned” can be used interchangeably. In other words, they can mean the same thing depending upon the circumstances.
However, if the original creditor (OC) sold your account, its entry on your credit report should show either “sold” or “transferred”. That would mean your debt has been purchased by another entity.
In addition, the OC’s entry would have to show a -0- balance indicating that no money is owed to the OC. It means the OC no longer has anything to do with the account and the balance is now owed to the buyer of the account.
Rather than sell an account right off the bat, some OCs will hire collection agencies to collect. Those agencies do not purchase accounts but merely collect for the OC. If the account was assigned to a collection agency to collect for the OC, the OC’s Credit report entry will NOT show the state that the account was “sold” or “transferred” and will continue to show that a balance is owed.