File a Canadian patent application: Request examination


5. Request examination

Examination is the process we use to decide if your application meets the requirements for your invention to be granted a patent. Your application is not automatically examined when it's filed. To have your patent application examined, you must send a request for examination.

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When to request examination

You can request examination when you file your application. Otherwise, for most applications, you have up to 4 years from your filing date to make a request for examination.

You will not receive a reminder that a request for examination of a patent application must be made by a certain date.

If you do not make a request within the 4 year period, you'll receive a notice and have 2 months to request examination and pay the late fee and examination fee.

If you never make the request or don't pay the fees in time, the application will be deemed abandoned.

How to reinstate an abandoned application

Reasons some choose to delay requesting examination

You may file your patent application and delay requesting the examination so that you can:

  • have time to assess the feasibility and marketability of your invention
  • keep potential competitors from infringing on your invention by filing first
Advanced examination

We examine patent applications in the order in which requests are made. You can ask for your application to be examined sooner by expediting your patent application.

Advanced patent examination

How to request examination

If you don't request examination when you file using e-filing, to request examination, write a letter that includes:

  • the name and address of the person making the request
  • the name of the applicant (if the person making the request is not the applicant)
  • the patent application number (or information sufficient to identify the application)

Pay the fee

You must pay the basic portion of the fee for requesting examination as well as an excess claims fee for each claim over 20 contained in your application on the day you request examination. If you miss the deadline, you'll be charged a late fee. We will send you a notice and give you 2 months to request your examination and pay your fees.

If your application is a Patent Cooperation Treaty application where the international search was carried out by the Commissioner (i.e. by an examiner), you may be entitled to a further reduction of the examination fee.

Accepted forms of payment

To pay your fees online you can only use:

Use the general correspondence form to request examination or pay your fees if you have already filed your patent application.

Pay fees through the general correspondence form

Service standards for examination fees

What to expect

CIPO receives a large number of patent applications, so the examination process may take more than 2 years.

Most applications face questions (or objections) from examiners. During this stage of the process, we may go back and forth to resolve issues in your application that can keep it from being approved. You must respond to every question or objection we have. Missing deadlines could result in your application being abandoned.

Maintenance fees

While your application is pending and after it's granted, you need to pay annual maintenance fees. Learn how and when to pay patent and patent application maintenance fees.