If you want to obtain a patent in a country other than the United States there are several paths you can take to achieve this goal. They are as follows:

1. You can file directly in the country of choice
2. You can file a PCT application and then later designate your countries of choice so long as that country is a PCT member
3. You can file a utility patent application in the U.S. and within 12 months from filing do either items 1 and/or 2

Each of these options has pros and cons which need to be carefully considered. The most important consideration is timing. Failing to take whatever steps are needed within the time frames required to preserve your international filing rights causes these rights to be irretrievably lost. If a patent application is already pending in a PCT member country (of which the US is one), you must file the PCT application within one year from the filing date of the priority application. The PCT is often favored as an avenue for preserving international filing rights because it enables applications to wait up to 30 months from the initial priority date dates before a decision must be made about what countries to seek patent protection in.  The timeline below illustrates how the PCT process works.

The advantages of the PCT are that it:

1. Enables the applicant to delay the expense of filing international patent applications

2. Provides an examination process that enables the applicant to assess the likely patentability of the idea before further examination costs are incurred.

3. Provides the applicant with a way to amend and modify the application to put it in good form for examination before any examination occurs

4. Most countries of interest are PCT members so by filing a PCT application you preserve rights in numerous countries for at least 30 months and longer if you then go through the examination process in that country.

There are many nuances that go into an international filing decision and if you are considering how to protect your invention internationally you should get in touch with a qualified patent attorney.