If you are interested in patenting your invention outside of the US, a PCT (Patent Cooperation Treaty) application can be used to obtain a search and extend your deadlines to make foreign filing decisions.
The PCT procedure consists of two main phases: the international and the national/regional phase. In the international phase, an international search report and patentability opinion are given. The application is published at 18 months from your earliest priority date (for example, the filing date of a US provisional application). Deadlines to enter the national phase differ by country, but are typically 30 or 31 months from the priority date. Considering that the foreign filing deadline is 12 months if the PCT is not used, this process extends the time to make major financial decisions by about 18 months.
Please note that PCT international applications DO NOT result in an “international patent”. Patents are only issued in the national phase by the individual offices in the regions for which patent rights are sought. Independent examination will be conducted by the elected regional offices.
The primary output of the international phase is the international search report (ISR) and patentability opinion. A favorable ISR may be used to accelerate examination in the national phase in many countries.
PCT applications may claim priority to the filing date of a national patent application (including a US provisional application) filed within the preceding year. If you have filed a US provisional application and intend to file a PCT application, you can save money by directly claiming priority to the US provisional filing date in the PCT filing, and following up with a US utility application in the national phase. An alternative is to file a US utility application claiming benefit of the provisional, and then file a PCT application claiming priority of the US utility and provisional applications. This approach may result in faster examination in the US, but can be more costly and does not take advantage of the international search results and other factors which are beneficial to a national stage application.