The Patent Co-operation Treaty (PCT) is an international treaty which enables an inventor to obtain patent protection in a number of different countries without incurring the expense of filing individual patent applications in those countries. Although the cost of pursuing a treaty application is quite high, the ultimate cost can often be passed on to the distributor or the manufacturer in the various foreign countries in which you want to sell your product. If you file individually in these several foreign countries, you will most likely be paying those costs yourself.