File an international patent through the Patent Cooperation Treaty (PCT)


Patent Cooperation Treaty (PCT) kit

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What is the Patent Cooperation Treaty?

The Patent Cooperation Treaty (PCT) is an international treaty administered by the World Intellectual Property Organization (WIPO). Under the PCT system, you may file for a patent in as many as 153 member countries through a single international application filed in Canada.

More precisely, after you have filed an international application in Canada, you have automatically designated and elected all of the signatory countries to be able to seek patent protection in those countries at the national level. The granting of patents remains the responsibility of each national patent office.

Overview of the Patent Cooperation Treaty system

What is WIPO?

WIPO is an agency of the United Nations dedicated to intellectual property issues. In its role as administrator of the PCT, WIPO is referred to as the International Bureau and carries out five major processing functions:

  • receives the application
  • receives amendments to the patent claims
  • undertakes international publication
  • communicates your application and an international search report to patent offices in the countries you designate and elect; and
  • communicates an international preliminary report on patentability (Chapter I or Chapter II—see below under Chapter designation) to patent offices in the countries you designate or elect.

In addition, WIPO produces various materials that provide information related to patents and the PCT, including:

  • the PCT Applicant's Guide, a comprehensive guide that addresses each step of the PCT filing process, including requirements for national entry into the contracting states
  • the PCT Gazette, which is published weekly and contains notices and indexes relating to the publication of individual international applications and general information concerning the PCT
  • the PCT Glossary, which aids in the understanding, drafting or translating of PCT documentation; and
  • access to PATENTSCOPE®, a database that houses PCT applications that have been published along with national entry information, and facilitates the search of international patent applications.

Why would I file internationally?

A Canadian patent does not protect your invention in another country.

For example, suppose you have invented a mountain-climbing snowmobile and hope to corner the market in countries where the machine may be in demand. You will probably want a patent not only in Canada, but also in the United States, Austria, Germany and wherever else a mountain-climbing snowmobile could be used. You might also want a patent in Japan, where many snowmobiles are manufactured. Otherwise, someone in one of those countries might copy your invention and market it in competition with you.

The PCT procedure simplified

The PCT procedure has two main phases: an international phase and a national phase. The expressions "international phase" and "national phase" are not official PCT terms, but have utility and have become well known.

1. International phase


You file an international application, which complies with the PCT formality requirements, in one language, and pay one set of fees. The patent office processes the application and gives it an international filing date and international application number.

International search

An International Searching Authority identifies (in an international search report) any published documents that may have an influence on whether the invention is patentable, and then summarizes the invention's potential patentability in a written opinion.

Publication of documentation

Shortly after 18 months from the earliest priority date, the contents of the international application are published along with the international search report.

Chapter designation

Should you decide to continue with the application process, you must then choose which course to pursue:

  1. Chapter I of the PCT—This is the default designation. If you choose to continue with Chapter I of the PCT, the application will proceed to the national phase upon your action. In accordance with Article 19 of the Treaty, after you receive the findings of the international search report, you are entitled to a one-time amendment of the claims. You must file any amendments with the International Bureau. The written opinion will serve as the international preliminary report on patentability and will be communicated to the PCT Member states where you are seeking patent protection. These states are referred to as "designated" states.
  2. Chapter II of the PCT—If you wish, file a PCT/IPEA/401 form (referred to as a "demand") with an International Preliminary Examining Authority (IPEA). You should consider filing a demand if you are not sure about your chances of getting patent protection. The IPEA will do an additional patentability analysis (referred to as a written opinion of the IPEA). In accordance with Article 34 of the PCT, you may amend any part of the specification, and all amendments will be transmitted directly to the IPEA for analysis. A final report, called the international preliminary report on patentability (IPRP) will be communicated to you and the states where you are seeking patent protection. These states are referred to as "elected" states. The IPRP offers a non-binding opinion on whether the invention is novel, involves an inventive step and has industrial applicability.
Communication with national offices

The national or regional intellectual property office of a designated or elected state will request from the International Bureau a copy of the published international application and the international search report. It will also ask for the international preliminary report on patentability (Chapter I or Chapter II, as required).

2. National phase

You can now seek patent protection from the national or regional intellectual property offices of the states that you designated and elected during the application process. In each national or regional office, you must also pay applicable fees and provide any necessary translations.

It is important to note that in the national phase, any intellectual property office is free to apply its national or regional law to determine patentability. The intellectual property offices will examine the international application based on prior art (information that might cause a patent examiner to raise a defect to one or more of your claims) and any other conditions of patentability that are not requirements of the international application.

Each PCT Member state has given a detailed summary of the requirements for entry into their national phase. However, as practices and rules may change, the only authentic sources of information on requirements are the laws, rules and regulations of each state.

Consider using a patent agent

Intellectual property offices inform applicants of the services provided by licensed patent agents. Patent agents have expert knowledge and experience that you can use during the preparation and prosecution of your patent applications The College of Patent Agents and Trademarks Agents' website provides a list of licensed patent agents who can represent you before the Canadian Patent Office.

Minimum requirements for filing

You are entitled to file an international patent application if you are a national or resident of one of the PCT contracting Member states. If there are several applicants named in the international application, only one of them needs to comply with this requirement. An international patent application must be prepared according to certain formal requirements set out in the PCT and its regulations. WIPO's PCT Applicant's Guide—International Phase (PDF version) sets outs these requirements. If you follow these requirements, you will not have to adapt to various national or regional formality requirements later.


WIPO uses standard forms to collect information during the application process. The WIPO PCT forms page offers editable copies of the required PCT forms, as well as samples of properly completed forms.


For the application to be recognized by the International Bureau (WIPO), it must also be accompanied by the required fees. You must pay all required fees within one month from the date that the international application is received; late payments are subject to an additional fee. Fees to be transmitted include:

  • Transmittal fee ‐ This fee is intended to compensate the receiving Office (RO) for the work it does in connection with the international application
  • International filing fee ‐ This is a fee paid to the RO for the benefit of the International Bureau when filing an international application.
  • Search fee ‐ This fee is paid to the RO for the benefit of the International Searching Authority for carrying out the international search.
  • Handling fee - This is a fee paid to the IPEA for the benefit of the International Bureau for filing a demand on an international application
  • Preliminary examination fee ‐ This fee is paid to the IPEA for conducting an examination of the application.

How to file an international application

Once you have prepared the international application according to the PCT requirements, you should file it. You have four options for filing:

1. International Bureau as the receiving office

An international application may be filed directly with the International Bureau. The International Bureau will act as the receiving office; however the international searching authority (ISA) and international preliminary examining authority (IPEA) are determined based on the contracting Member state, which is the same as your nationality or country of residence. Where two or more applicants are from different contracting Member states, filing the international application with the International Bureau may result in a wider choice of authorities. In such a circumstance, the choice of ISA must be shown in the request and the choice of IPEA must be shown in the demand.

The International Bureau will receive international applications by:

International Bureau of WIPO
PCT Receiving Office Section
34, chemin des Colombettes
1211 Geneva 20

Electronic format – visit WIPO's Direct Filing webpage

You can use ePCT to prepare, validate and file a PCT application with the International Bureau as receiving office. The International Bureau will then transmit it to CIPO as the international searching authority. This process is explained in the e-PCT user guide and frequently asked questions concerning ePCT, which are available from the WIPO PCT Portal.

If your nationality and residence are Canadian, then only Canada will be available as an international searching authority (ISA). However, if you have different states of nationality or residence, you will need to choose the ISA. In any case, you will have to click on the drop-down menu to indicate the ISA, as shown below:

International Searching Authority - CA - Canadian Intellectual Property Office
Screenshot from ePCT

2. National office as the receiving office

You may file an international application with the national office of the PCT contracting Member state where you are a resident or national, or with the office acting for that state. If there are two or more applicants, it is fine if only one of the applicants satisfies this requirement.

To file the international application with Canada as the receiving office, please address your applications to the Commissioner of Patents and send the application by:

Mail or in person
Canadian Intellectual Property Office
Place du Portage I
50 Victoria Street, room C114
Gatineau, QC K1A 0C9 (Courier: J8X 3X1)

By facsimile
819-953-CIPO (6742)
819-953-OPIC (2476)

Note: Faxes sent to any other number will not be considered received by CIPO.

Electronic Format

We will consider correspondence sent electronically, including by fax, to be received on the day that it is transmitted, if it is delivered and completely received before midnight, local time at CIPO and be accorded that day in office records, irrespective if CIPO is open for business. For any other physical correspondence delivered on a day when CIPO is closed for business, we consider it received on the next day CIPO is open for business.

Electronic filing using ePCT online service

You can use ePCT to prepare, validate and download an e-filing package to be transmitted to CIPO as the receiving Office. CIPO, as a receiving Office, does not accept direct online filings of international applications through the ePCT online service. Once you have prepared the e-filing package with the ePCT online service, you will need to visit CIPO's PCT e-filing page to submit the e-filing package.

PCT international correspondence to CIPO

Following initial filing, we encourage you to submit any documents or correspondence related to your PCT international application using our general correspondence form.

You may also submit correspondence by regular mail, in person, Canada Post Xpresspost, or facsimile.

PCT international correspondence from CIPO

By default, we send all outgoing PCT international correspondence via Canada Post regular post. If you'd prefer to receive electronic correspondence via Canada Post epost Connect, you must complete our consent form (PDF: 155 KB; 2 pages). Note that we've verified the accessibility of this PDF.

The Canadian Intellectual Property Office

The Canadian Intellectual Property Office (CIPO) plays a role at both the international phase and national phase of the PCT system. These roles include:

  • receiving office (RO)
  • international searching authority (ISA)
  • international preliminary examining authority (IPEA)
  • designated/elected office

International phase

CIPO's Patent Office has three distinct roles during the international phase.

1. Receiving Office

If you or one applicant from your group of applicants is a national or resident of Canada, the application may be filed with CIPO. You must file the application in either English or French. You must use Canadian currency to pay the transmittal, international filing and search fees within one month of receiving the international application. These and further requirements are outlined in WIPO's PCT Guide (PDF version). Here are the four steps involved:

  • Step 1
    CIPO receives the international application from you.
  • Step 2
    CIPO checks the international application to determine whether it meets the requirements for form and content of international applications. This check is formal in nature only and does not go into the substance of the invention.
  • Step 3
    If the international application meets the PCT requirements for giving the application an international filing date, CIPO accords the international filing date and international application number.
  • Step 4
    CIPO transmits the "record copy" of the international application to the International Bureau, creates and keeps a "search copy" for its roles as an international searching authority once the fees have been paid and keeps one copy as the "home copy."
2. International searching authority (Chapter I)

Where an international application is filed with Canada as the receiving Office, CIPO will serve as the ISA. Canadian examiners will produce an international search report and a written opinion of the ISA (WO-ISA). The WO-ISA provides the applicant with a preliminary, non-binding opinion on the issues of novelty, inventive step and industrial applicability of the patent. This allows the applicant to assess, at the search stage, whether to proceed to the national/regional phase. If no demand for international preliminary examination is filed, the WO-ISA will be converted by the International Bureau into an international preliminary report on patentability (IPRP Chapter I). These and further requirements are outlined in WIPO's PCT Applicant's Guide.

3. International preliminary examining authority (Chapter II)

CIPO will carry out an international preliminary examination on condition that you have filed a "demand" form and paid the accompanying fees. You need to indicate in the demand if the application is to be examined as originally filed or amended in accordance with the PCT. The purpose of the international preliminary examination under Chapter II is not to grant or refuse a patent, but to provide a preliminary and non-binding opinion on whether the claimed invention appears to be novel, involves an inventive step and has industrial applicability. These and further requirements are outlined in WIPO's PCT Applicant's guide.

Questions during the international phase

Prior to filing, you can contact either WIPO or CIPO with general questions about the PCT system, including how to file an international application and the procedure you need to follow during the international phase.

National phase

If you have designated and elected Canada for national patent protection, there are a few requirements that you need to fulfill to successfully enter the "national phase" in Canada. You must pay a basic national fee to enter Canada's national phase. Other requirements include submitting the application in either English or French, where the international application is not in English or French and paying maintenance fees for each one-year period from the international filing date starting on the 2nd anniversary of the filing date. Additional requirements are listed in WIPO's PCT Applicant's Guide (PDF version).

The time limit for entering Canada's national phase is 30 months from the earliest priority date or if no priority claim was made, from the international filing date (the date on which the application met the requirements under PCT). You may enter Canada's national phase if the requirements to enter national phase are met within 12 months after the 30-month deadline, provided you submit a request that the rights of the applicant be reinstated with respect to that international application, a statement that the failure was unintentional, and the fee for reinstatement of rights. Upon national entry, the application is considered a national application and prosecution of the patent application is carried out according to statutory requirements as contained in the Patent Act and Patent Rules. Copies of these legal texts and additional information are available from the CIPO website.

While all applicants may use the services of a patent agent, and benefit from their experience and knowledge in preparing and prosecuting applications with CIPO, where the applicant is not the inventor of the alleged invention, you must appoint a patent agent. Once you have appointed a patent agent, CIPO will correspond with the patent agent concerning the prosecution of the application. Only patent agents licensed by the College of Patent Agents and Trademark Agents can conduct business with us.

Summary of links

This list of useful links has been compiled to facilitate the understanding of the international filing system.