A significant change to USPTO patent practice takes effect on July 20, 2026. Canadian patent applicants and patent owners will be required to use a US registered patent practitioner for many patent matters before the USPTO.
Canadian patent agents and lawyers registered before the USPTO continue to qualify as US registered patent practitioners for applicants domiciled in Canada. Canadian applicants may therefore continue to pursue US patent protection through qualified Canadian practitioners. Qualified Canadian patent lawyers registered before the USPTO allow Canadian applicants to coordinate North American patent strategy, prosecution and portfolio management through a single team.
Canadian applicants that currently file directly with the USPTO, or work through representatives who are not registered before the USPTO, should review upcoming US filing deadlines and planned submissions now and ensure that appropriate representation is in place before the new rule takes effect.
The New Requirements at a Glance
The new rule requires patent applicants and patent owners domiciled outside the United States and its territories to be represented by a registered patent practitioner in many patent matters before the USPTO.
In practical terms, the requirement extends across much of the patent lifecycle, including priority claims, inventorship submissions, application data sheets, amendments, Office Action responses, petitions, continuation applications, PCT national phase entries, reissue proceedings and reexaminations.
Whether the rule applies depends on domicile, not citizenship, nationality or place of incorporation. For individuals, domicile generally refers to permanent legal residence. For organizations, domicile generally refers to the principal place of business. As a result, an applicant with a US mailing address, branch office or subsidiary may nevertheless be considered foreign-domiciled for purposes of the new requirement.
Failure to satisfy the new requirements may affect priority claims, inventorship submissions, application data sheets and certain certification-related filings. In some circumstances, filings may not be accepted or may not have their intended legal effect.
What Does This Mean for Canadian Applicants and Owners?
Canadian patent applicants and owners may continue to pursue US patent protection through Canadian patent agents and lawyers registered before the USPTO. The rule does not change the existing framework of the USPTO regulations, which allows qualified Canadian practitioners to represent Canadian applicants before the USPTO. For applicants already working with such practitioners, the new rule should generally not require a change in counsel.
Canadian domiciled applicants and owners that currently file certain US matters directly, or work through separate advisers, may wish to consider whether a more coordinated approach would better support their North American patent strategy.
For businesses managing patent portfolios across Canada, the United States and other jurisdictions, this creates an opportunity to reconsider how North American patent matters are managed. A coordinated approach may reduce administrative complexity, provide a single point of contact across jurisdictions, streamline filing and prosecution strategies, improve visibility across related matters, and allow Canadian applicants to work with advisors familiar with both Canadian and US patent practice while maintaining direct access to both patent systems.
How Cassels Can Help
The Cassels Intellectual Property Group has extensive experience advising Canadian and international clients on patent matters in Canada, the United States, and other jurisdictions. Cassels also has extensive experience representing Canadian patent applicants and owners before the USPTO.
For Canadian applicants and patent owners affected by the new rule, Cassels can assist in assessing how the new requirements apply to existing and future US patent matters and developing coordinated patent strategies across Canada and the United States. By coordinating Canadian and US patent matters through a single team, Canadian applicants may benefit from a more streamlined approach to portfolio management, greater visibility across related matters, a single point of contact for cross-border patent issues, and more consistent filing and prosecution strategies across jurisdictions.
Whether you are reviewing existing US patent matters, planning future filings or evaluating your broader North American patent strategy, we would be pleased to discuss how the new requirements may affect your portfolio.