Outlier Patent Attorneys

International Patent Filing: PCT Applications


In the United States, a domestically-awarded patent confers legal rights to an inventor strictly within the national boundaries (they have no legal weight in other nations).  If you’re looking for international patent protection, know that an international patent application does not exist since most countries operate under their own unique patent laws. 

However, there is a close alternative to an “international patent application” called the "PCT application".  The PCT application provides a unified process of filing patent applications in over 156 countries globally, including most of the major industrial nations. 

As an inventor eyeing international reach, a PCT application could be your best bet.  Before you decide to seek protection internationally, understand PCT applications and consider whether they may be the right alternative to filing separate patent applications in each country you seek patent protection.


Patent rights in the United States are confined to its domestic geographical boundaries.  The PCT application, essentially an "international provisional application," functions as a placeholder, enabling inventors to simultaneously seek protection across various nations without resorting to multiple, separate filings.  This process includes initial filing, publication, creation of international search reports, optional preliminary examination, and entry into the national phase in each desired country.  Filing a PCT application can save time, money, and streamline the patent application process. 

The PCT: A Brief History

The PCT, or Patent Cooperation Treaty, is essentially a cooperative agreement between many countries worldwide, aimed at simplifying global patent protection.  Established in 1970 and implemented in 1978 under the administration of the World Intellectual Property Organization, the PCT has transformed the once complex, expensive, and time-consuming task of applying for patents in multiple nations into an efficient process.

See more details on the PCT member countries here

What is a PCT Application?

Think of the PCT application as an international provisional utility patent filing, or an international placeholder for a utility patent.  It lets you seek protection for your invention across multiple nations with a single filing, resulting in an international “patent-pending” status. 

However, a PCT application does not directly result in an issued patent.  It's simply a way of seeking protection for your invention in multiple countries at once without having to file separate applications for each country individually.  Subsequent to the PCT filing, inventors are still required to submit national phase applications to pursue patents in each country of interest individually.

Advantages and Disadvantages

A PCT application can reduce costs since only one fee needs to be paid compared if you had filed separate applications for each country individually.  For example, the European Patent Office (EPO) and the United States Patent and Trademark Office (USPTO) have different fee structures, which would require planning and separate budgeting for each application. 

Additionally, the PCT process can entail less translation costs.  The international application can be filed in one of WIPO's official languages (English, French, or Spanish) and translated into other languages only when necessary.  

Another key benefit of the PCT process is that it provides inventors with additional time to decide which countries they want to file their patent applications in.  Once the international patent application is filed, the inventor has 30 months from the priority date to file national or regional patent applications in the designated countries.  This can be particularly helpful for inventors who need time to evaluate the commercial potential of their invention before committing to the costly and time-consuming process of filing patent applications in multiple countries. In essence, it can give you much more time to assess the value of the invention and viability in worldwide markets.

The flip side is that a PCT application can delay the deadline for individual national filings, which can give you the benefit of time and keep your foreign filing options open.  While it initiates the international filing process and grants an international patent-pending status, it does not guarantee any foreign patents.  

The PCT Application Process

The PCT process starts with a preliminary examination and the creation of an international search report that identifies pertinent prior art and provides an opinion on the invention's patentability.  The subsequent stages of the process involve filing national or regional applications in the desired countries.

Here is a probable outline of the PCT application process:

  • The Initial Filing: The inventor files an international patent application either with their national patent office or directly with WIPO.

  • Publication: WIPO publishes the application within seven days, making it publicly available.

  • International Search Report: An International Searching Authority (ISA) provides an international search report and a written opinion on the patentability of the invention.

  • Supplementary International Search: The applicant may request a supplementary international search before 22 months from the priority date.

  • International Preliminary Examination (Optional): The applicant can request an international preliminary examination between 22 to 28 months from the priority date.

  • National Phase Entry: The applicant must enter the national phase in each country where protection is sought within 30 to 45 months of the priority date.

In the PCT process, inventors have about 18 additional months—usually 30 months from the original patent application filing—to initiate national phase procedures with individual patent offices. This window allows inventors to assess the feasibility of obtaining patents and the commercial viability of their invention in prospective countries.

However, inventors need not wait for the full 30-month period before starting the national phase—they can request an early start.  Once the national phase begins, the examination time for the patent application varies across different offices globally. 


Q: When should a PCT application be filed?

File a PCT application when you are looking to get patent protection for your invention in multiple countries outside of the US. As discussed, the PCT process provides a streamlined and cost-effective approach to filing international patent applications. The benefit? It can provide inventors with additional time to evaluate the commercial potential of their invention before committing to the expensive and long process of filing patent applications in multiple countries.

In general, a PCT application should be filed within 12 months of the filing date of the first patent application for the invention (aka the priority date). This initial patent application can be a provisional or non-provisional application filed in the inventor's home country. Filing the PCT application within 12 months of the priority date ensures the invention is protected in the countries where the inventor intends to seek patent protection.

Filing a PCT application delays the need to file individual national or regional applications for up to 30 months, giving inventors more time to decide which countries they want to enter and to evaluate the commercial potential of their invention. A PCT application is filed under the PCT with a qualified international receiving office. Once filed, applicants have up to 30 months to decide which countries they would like to pursue their patents in.