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Key Features of Canadian Patent Prosecution for Foreign Associates

By: Christopher Heer | Last updated: August 14, 2018
Generally speaking, prosecuting patent applications in Canada is similar to prosecuting patent applications in the United States. Below are particular features of the Canadian Patent Act, Canadian Patent Rules and practice before the Canadian Patent Office that an instructing patent agent should take note of:

Pre-Filing Considerations

One Year Grace Period

Canada has a one-year grace period for enabling disclosures which runs back from the Canadian filing date.

However, note that the one-year grace period in Canada only protects the applicant against other applications which are based on the applicant’s prior disclosure. If a third party files an application during the grace period which is not based on information received directly or indirectly from the applicant, it will pre-date the applicant’s filing and may prevent the applicant from obtaining patent rights.

No On-Sale Bar in Canada

There is no on-sale bar in Canada. Any prior sale must constitute an enabling disclosure of the subject matter of the invention in order to anticipate a patent claim.

Patent Drafting Considerations

Incorporations by Reference Are Not Permitted

Incorporations by reference are not permitted in the patent specification in Canada.

Prior applications, patents and other documents may be referred to in the specification if they are public and sufficient identification of the public document is provided without including incorporation by reference language.

No Claim Surcharges

There are no claim surcharges in Canada of any kind.

Excess Page Surcharge

There is a surcharge for patent applications exceeding 100 pages, which becomes payable after the Canadian patent application has been allowed.

Methods of Medical Treatment Are Not Patentable Subject Matter

Methods of medical treatment are not patentable in Canada. However, similarly-worded “use” claims are allowable in Canada.

Higher Life Forms Are Not Patentable Subject Matter

Higher life forms are not patentable in Canada. Higher life forms are generally defined as multicellular life forms and include animals at any stage of development from fertilized eggs and totipotent stem cells (which have the inherent ability to develop into animals) onwards, as well as plants, seeds and mushrooms.

In contrast, lower life forms are patentable in Canada. Lower life forms are generally defined as unicellular life forms and include microscopic algae, unicellular fungi, bacteria, protozoa, viruses, transformed cell lines, hybridomas, and embryonic, pluripotent and multipotent stem cells.

Patent Prosecution Procedures

Flexible Examination Timing

Accelerated examination is available in Canada right from the filing date without affidavit evidence.

To request advanced examination, applicants must open the application to public inspection, pay the required examination and advanced examination fees and file a statement that the failure to advance the application is likely to prejudice the applicant’s rights.

Once requested, advanced examination typically commences within four months and subsequent office actions will issue at an accelerated pace as well.

Alternatively, it is possible to delay examination until up to 5 years from the Canadian filing date simply by waiting until the deadline to file a request for examination. Strategically, this might be done to reduce prosecution overlap with other jurisdictions thereby lowering worldwide prosecution costs.

No Information Disclosure Statement Requirement

In Canada, patent applicants do not have a positive obligation to identify or file all known material prior art to the Canadian Patent Office, although the applicant may voluntarily file prior art to ensure that it is explicitly entered on record.

The applicant is only required to identify or file prior art when the Examiner requests that the applicant identify the prior art cited in corresponding patent applications in other jurisdictions.

Annual Maintenance Fees for Canadian Patent Applications and Patents

There are annual maintenance fees payable to the Canadian Patent Office in a Canadian patent application and an issued patent from the second anniversary of the Canadian filing date to the end of the 20 year patent term.

Maintenance fees due while an application is pending may only be validly paid by the patent agent of record.

12 Month Reinstatement Period

If a maintenance fee is missed, or an application goes abandoned for any other reason, such as failing to respond to an office action, the application may be reinstated within 12 months of the date of abandonment upon making a request for reinstatement, paying a reinstatement fee and taking the action required which led to the abandonment.

There is no requirement before the Canadian Patent Office to explain how or why the abandonment occurred.

No Continuation or Continuation-In-Part Applications

There are no equivalents to continuation and continuation-in-part applications in Canada. The applicant must file a new patent application in order to claim new subject matter.

Divisional Application Practice

Due to restrictive double patenting laws in Canada, divisional applications are seldom employed unless in response to plurality of inventions rejections from the Patent Office.

No File Wrapper Estoppel

In Canada, the prosecution history of a patent before the Canadian Patent Office or elsewhere cannot be used for the purpose of construing patent claims in litigation, although the prosecution history may be admissible for certain invalidity attacks.


Hopefully this article has given you a better understanding of some of the features of the Canadian patent system. If you have any questions about the patent application process in Canada, please do not hesitate to contact us.