It doesn't work to cancel debts that are legitimately owed -- such as money your friend or father loaned you, or say a department store credit card where you received merchandise from that store AND the store did not sell the paper to another loan servicing company. If the department store kept the loan paper in-house, then that is a legitimate debt. The invalid debts, which this set successfully cancels, are the money-out-of-thin-air debts under the Federal Reserve system such as Visa, MasterCard, Discover, and other institutional credit issues.