Form of state rating legislation that allows each property/liability insurer to choose between using rates set by a bureau or its own rates. Individual states regulate insurers and approve their property insurance rates. There are three methods of rate approval in addition to open competition: prior approval rating, modified prior approval rating and file and use. At one time the insurance industry operated like a cartel, with rates set by bureaus and filed with the insurance commissioners of each state. Experts believed that competition would result in either unfairly high rates or unreasonably low rates that would lead to mass insurance company insolvencies. But open competition became widespread after New York State adopted it in 1969.