Have your say – Part 2: Canadian Patent Office seeking input on grace period for pre-filing disclosures

The Canadian Intellectual Property Office (CIPO) has launched a public consultation on Canada’s patent grace period for pre-filing disclosures. Canada’s grace period (12 months) is set out below. The consultation on pre-filing disclosures is open until June 23, 2026, and CIPO is seeking input from a broad class of stakeholders in Canada and abroad.

What you need to know

• CIPO is seeking stakeholder feedback on Canada’s grace period for pre-filing disclosures, to inform CIPO’s international engagement on grace period harmonization.
• Canada’s grace period currently covers the 12 months immediately prior to the Canadian application filing date (not the priority date).
• Disclosures made by inventors and applicants (or by those who obtained the information from them) during the grace period cannot be cited against the novelty and inventiveness of the patent claims.
• Grace period rules (and even the existence of a grace period) vary significantly across jurisdictions, which can create meaningful risks for applicants pursuing patent protection in multiple jurisdictions.

Grace periods explained

Disclosures of inventions before filing a patent application can happen for many reasons, both intentional and accidental. Common examples range from publishing a scientific paper, posting on clinicaltrials.gov, making a regulatory submission, and pitching to investors, to less obvious scenarios, such as fielding questions at a public presentation or catching up with peers at a conference. When these early disclosures are public—meaning that they are made to at least one person where there is no expectation of confidentiality or non-disclosure agreement—they can become hurdles to patentability.

An invention must be new and inventive to qualify for a patent. In jurisdictions that do not have grace periods for pre-filing disclosures (absolute novelty jurisdictions), any public disclosure before the filing date of a patent application can be cited against the novelty and inventiveness of its patent claims. In grace period jurisdictions like Canada, prior disclosures made by inventors and applicants (or by those who obtained the information from them) cannot be cited against the patent claims, provided that the prior disclosure was made during the grace period. These differences can have significant consequences for global filing strategies. For example, an applicant may be able to obtain patent rights despite an early disclosure made during the grace period in jurisdictions like Canada and the United States but be out of luck in absolute novelty jurisdictions like Europe.

In Canada, the grace period covers the 12 months immediately before the Canadian filing date (the Canadian filing date is the international filing date for a national phase application) rather than the priority date. Notably, the Canadian grace period is calculated differently than the US grace period, which can lead to tricky situations for applicants coordinating filing strategies, even within North America. Depending on the timing, this could mean that the same early disclosure by the applicant would be non-citable during US prosecution while being fatal to otherwise equivalent patent claims in Canada. While innovators generally appreciate that Canada has a grace period, interested stakeholders may wish to encourage CIPO to harmonize the calculation of Canada’s grace period with the US grace period.

What’s next: grace period consultation and survey

CIPO’s consultation on grace periods is wide-ranging, with CIPO looking to gauge stakeholders’ familiarity with the patent grace period, how they have navigated pre-filing disclosures in practice, and what risks or challenges they have encountered along the way. The findings will feed into CIPO's ongoing engagement in international discussions around grace period harmonization and will support the development of educational resources and outreach efforts. The grace period survey, which is open to stakeholders in Canada and abroad, also invites participants to share their views on harmonizing the patent grace period with other countries.

Interested stakeholders are encouraged to participate. This consultation is part of a two-part CIPO consultation that is open until June 23, 2026. See our accompanying bulletin, Have your say – Part  1: Canadian Patent Office seeking input on expedited examination.