Patents in Canada: A practical guide for foreign businesses 

Who this is for: Patent counsel, CTOs, and IP managers at foreign companies with technology, life sciences, clean tech, software, or AI innovations who need Canadian patent protection as part of their North American or global IP strategy. While the Canadian patent regime is broadly familiar to foreign practitioners, several aspects of Canadian law and practice differ materially from the US and European frameworks. These differences can affect patentable subject matter, prosecution strategy, claim drafting, deadline management, patent term adjustment, enforcement, and overall portfolio costs. As a result, decisions that are appropriate in other jurisdictions may not always produce the desired outcome in Canada. 

The assumption that costs foreign patent owners the most: Most foreign patent owners understand that patent protection must be obtained separately in Canada. The more common and costly assumption is that a filing and prosecution strategy developed for the United States, Europe, or the PCT process can be implemented in Canada with little or no modification. 

In practice, Canadian patent law contains a number of distinct procedural and substantive requirements that can significantly affect claim scope, prosecution costs, patent term, and enforceability. Decisions regarding claim drafting, examination timing, portfolio management, and responses to office actions often require a Canadian-specific analysis to achieve the desired commercial outcome. 

At the same time, these differences are not merely compliance considerations. Canadian patent procedure can also provide strategic opportunities that may enhance a broader North American or global patent portfolio. Depending on the circumstances, Canadian practice may offer additional flexibility in prosecution, claim management, and portfolio planning that can be leveraged to support overall patent objectives and cost-management strategies. 

Canada is therefore best viewed not as a routine extension of a foreign filing program, but as a jurisdiction that warrants its own strategic consideration. Early attention to Canadian-specific requirements and opportunities can help avoid unnecessary costs, preserve flexibility during prosecution, and strengthen the value of the resulting patent rights both in Canada and as part of an overall international patent strategy. 

Canada has a strong innovation economy with significant activity in software, artificial intelligence, telecommunications, clean technology, life sciences, pharmaceuticals, agriculture, advanced manufacturing and natural resources. Patent protection is often a critical component of a company’s Canadian market strategy, particularly where technological innovation represents a significant competitive advantage. 

Patents in Canada are governed by the Patent Act and Patent Rules. Canada is a member of the Paris Convention, the Patent Cooperation Treaty (“PCT”), the Patent Law Treaty and numerous international agreements that facilitate the acquisition and management of patent rights internationally. As a result, foreign businesses will find Canada’s patent system broadly familiar, although several Canadian-specific substantive and procedural rules can significantly affect filing strategy, prosecution costs, and enforceability. 

In this article:

1. Patentability requirements 

A Canadian patent may be granted for any new and useful art, process, machine, manufacture, composition of matter, or any new and useful improvement thereof. To be patentable, an invention generally must be: 

• novel; 
• useful; 
• non-obvious; and 
• directed to patentable subject matter. 

The Patent Act expressly excludes mere scientific principles and abstract theorems from patentability. Canadian courts have also developed specific jurisprudence relating to software, artificial intelligence, business methods, medical inventions, diagnostic methods and biotechnology. 

a. Patentable subject matter 

Software, artificial intelligence and computer-implemented inventions 

Software-related inventions are not categorically excluded from patent protection in Canada, however, Canadian practice differs from that of certain other jurisdictions. 

In March 2026, the Canadian Intellectual Property Office (“CIPO”) issued revised guidance regarding software, artificial intelligence and computer-implemented inventions. Under this guidance, patentability is based on purposive claim construction and a physicality requirement. In particular, the 2026 guidance places renewed emphasis on purposive construction as the starting point for patentable subject matter analysis. After identifying the essential elements of the claim through purposive construction, examiners assess whether the claimed subject matter has the requisite physicality, namely whether it forms part of a practical application that has physical existence or manifests a discernible effect or change. For computer-implemented inventions in which the computer is the only physical element, examiners are directed to consider whether the claim is distinguishable from merely programming an abstract idea, mathematical formula, scientific principle or abstract theorem on a computer, making careful claim drafting and claim-specific analysis particularly important..  

As a result, Canadian filing and prosecution strategies for software and AI inventions must be reviewed independently rather than simply mirroring claim formats from the US or other jurisdictions. A claim set that is allowable at the USPTO may not satisfy the Canadian physicality requirement. Foreign companies filing software or AI patent applications in Canada should have their claim sets reviewed for Canadian patentable subject matter compliance before requesting examination, when amendment is most cost-effective. 

Life sciences and medical innovations 

Similarly, patentability issues frequently arise in the life sciences field. Methods of medical treatment have long been treated as non-patentable subject matter in Canada. 

The scope of this exclusion was recently clarified by the Supreme Court of Canada in Pharmascience Inc. v. Janssen Inc., 2026 SCC 26. The Court confirmed that pharmaceutical dosing regimens are not automatically unpatentable merely because they involve administration of a medicine. Rather, the focus is whether the claim seeks to monopolize professional medical skill and judgment. The Court upheld patent claims directed to a specific dosing regimen for a pharmaceutical product, providing important guidance for pharmaceutical and biotechnology companies and greater certainty regarding the patentability of dosing-related innovations. This decision is expected to influence patent drafting and prosecution strategies in Canada. 

2. Obtaining patent protection 

Patent protection in Canada may be obtained either by filing a Canadian patent application directly with CIPO or by entering Canada through the PCT national phase. 

Canada operates on a first-to-file system. Businesses should therefore consider patent filings early and before any public disclosure whenever possible. 

The filing requirements in Canada are similar to other jurisdictions with the following notable features. 

a. Grace period 

Canada provides a 12-month grace period for disclosures originating from the inventor or applicant. Subject to certain limitations, an inventor’s own public disclosure made within 12 months before filing will not necessarily invalidate a later Canadian patent application. Nevertheless, applicants should avoid relying on the grace period whenever possible, particularly if protection in foreign jurisdictions is contemplated. 

b. Priority claims 

Canada recognizes priority claims under both the Paris Convention and the PCT. In general, a Canadian patent application claiming priority from an earlier application must be filed within 12- months of the filing date of the earlier application. 

A feature of the Canadian system is that is provides greater flexibility for correcting and perfecting priority claims. In many circumstances, the deadline for making a priority request is the later of sixteen months from the earliest priority date and four months from the Canadian filing date, subject to certain limitations. As well, as part of Canada’s implementation of the Patent Law Treaty, applicants may now be able to restore a lost priority right in certain circumstances. Where an application is filed after the normal 12-month priority period but within an additional two-month period, restoration may be available if prescribed requirements are met. This can provide an important safeguard where a priority deadline has inadvertently been missed.  

c. Small entity status: reduced fees 

Canada provides reduced government fees for applicants that qualify as a “small entity”. In general, a small entity includes businesses that employ 100 or fewer employees and certain universities. Qualifying applicants may benefit from reduced filing, examination, maintenance and other official patent fees.  

Small entity status should be assessed carefully at the time of filing and throughout prosecution. An incorrect small entity claim may have consequences for the validity and enforceability of a patent, and businesses should ensure that their eligibility is reviewed before claiming reduced fees. 

3. Patent prosecution 

Unlike some jurisdictions, examination is not automatic in Canada. An examination request must be filed within the prescribed period (4-years from the Canadian filing date) and accompanied by the required fee. 

Recent amendments to the Patent Rules have made prosecution strategy increasingly important. For applications for which examination is requested on or after October 3, 2022: 

• excess claim fees apply to claims exceeding twenty; 
• requests for continued examination (“RCEs”) may be required after a prescribed number of examination reports; 
• conditional notices of allowance may be issued where only minor deficiencies remain; 
• ST.26-compliant sequence listings are required where applicable; and 
• claim management has become a significant consideration in controlling prosecution costs.  

Although Canada now imposes excess claim fees, the system remains relatively flexible. There is no restriction on the number of independent claims, and multiple dependent claims remain permissible. Strategic claim drafting and claim count management can significantly reduce prosecution costs while maintaining meaningful protection. 

Unlike the United States, Canada does not provide continuation practice. While divisional applications are available, they must be managed carefully in view of Canada’s double patenting jurisprudence. Accordingly, decisions regarding claim strategy and divisional filings should be considered early in the prosecution process. 

a. Due care standard and third-party rights 

Recent amendments have also introduced a due care standard for certain missed deadlines. 

In particular, where certain maintenance fee deadlines or examination request deadlines are missed, reinstatement may require a showing that the failure occurred despite the exercise of due care in the circumstances. If the required standard is not met, patent rights may be permanently lost. 

The due care regime has significantly increased the importance of robust docketing and deadline management systems. Foreign applicants accustomed to more forgiving restoration procedures in other jurisdictions should be aware that Canadian rights may be lost if critical deadlines are missed and the applicable due care requirement cannot be met. In addition, third-party rights may arise during certain periods following abandonment or lapse, potentially limiting the enforceability of subsequently reinstated patent rights.  

b. Accelerated examination 

Several mechanisms are available to accelerate examination of Canadian patent applications. 

Patent Prosecution Highway 

Canada participates in various Patent Prosecution Highway (“PPH”) programs, allowing applicants to leverage favourable examination results obtained in participating foreign patent offices. Likewise, favourable results obtained in Canada may facilitate prosecution in participating foreign jurisdictions. 

Green technology applications 

Patent applications relating to technologies whose commercialization would help resolve or mitigate environmental impacts or conserve natural resources may qualify for accelerated examination through a simplified procedure. Canada has become an attractive jurisdiction for many clean technology innovators seeking faster patent protection. 

Special order examination 

In addition, accelerated examination may be available where failure to advance examination could prejudice the applicant’s rights. 

4. Patent term and patent term adjustment 

For patents filed on or after October 1, 1989, the patent term is generally 20 years from the filing date, provided maintenance fees are paid. 

Canada also provides patent term adjustment (“PTA”) in certain circumstances to compensate patentees for delays attributable to CIPO during prosecution. Although the availability of PTA is subject to specific statutory requirements, it represents an important recent development for patent owners with commercially significant patent portfolios.  

PTA is not automatic and is available only where the statutory requirements are satisfied. The amount of any adjustment depends on the extent to which delays are attributable to CIPO and may be reduced by certain applicant actions during prosecution. Accordingly, prosecution strategy can have a direct impact on the availability and duration of PTA. 

Businesses should be aware of several practical considerations: 

• Efficient prosecution may preserve PTA entitlement. Certain prosecution events, including the filing of a request for continued examination (“RCE”), may affect the calculation of PTA and should be considered as part of an overall prosecution strategy.
• The timing of examination requests may be relevant. Because PTA is linked to prescribed prosecution timelines, applicants should consider PTA implications when developing filing and examination strategies for important applications. 
• Portfolio management should include PTA review. For patents covering key products or technologies, applicants should assess potential PTA entitlement as part of their broader patent lifecycle and exclusivity planning. 
• The Canadian PTA regime has introduced a valuable tool for patentees seeking to maximize the effective term of protection for important inventions. Businesses with significant Canadian patent portfolios should consider the potential impact of PTA when managing prosecution strategy and evaluating the overall value of their intellectual property assets. 

5. Ownership, assignments and licensing 

Canadian patent applications identify both the inventors and the owner of the patent rights, referred to as the applicant. In the absence of an assignment, inventors are generally the initial owners of patent rights. 

Questions concerning ownership frequently arise where inventions are developed by employees, consultants, contractors or research collaborators. Businesses should ensure that employment agreements, consulting agreements and collaboration agreements clearly address intellectual property ownership and assignment obligations. 

Patent applications and patents may be assigned or licensed in whole or in part. Transfers and ownership changes may be recorded with CIPO, and businesses are generally advised to maintain accurate title records. Patent licenses may be exclusive, sole or non-exclusive and are principally governed by contract. 

6. Enforcement 

Patent rights may generally be enforced before the Federal Court of Canada and, in certain circumstances, provincial superior courts. 

An issued patent enjoys a presumption of validity, although it may be challenged on grounds such as anticipation, obviousness, lack of utility or non-patentable subject matter. 

A notable recent development is the increased relevance of the patent prosecution record during litigation. Section 53.1 of the Patent Act permits portions of the Canadian prosecution history to be introduced in certain circumstances to rebut positions taken by patentees regarding claim interpretation. Patent applicants should therefore exercise care when making arguments during prosecution, as those statements may later affect enforcement proceedings.  

Available remedies for patent infringement may include injunctions, damages, an accounting of profits, delivery up or destruction of infringing products and costs awards. 

How Miller Thomson can help  

Canadian patent practice rewards early planning and Canadian-specific strategy. The March 2026 CIPO guidance on software and AI, the 2026 SCC decision on pharmaceutical dosing regimens, the PTA system, the due care standard for missed deadlines, and the file wrapper estoppel-equivalent effect of section 53.1 have all changed the Canadian patent landscape materially in the past two years. A US or European prosecution strategy applied without Canadian-specific review may produce patents that are narrower, more expensive, or less enforceable than they need to be.  

Miller Thomson’s intellectual property team advises foreign companies on the full spectrum of Canadian patent practice, from patentable subject matter analysis and filing strategy through prosecution management, PTA assessment, divisional strategy, assignment and licensing, and enforcement before the Federal Court. Our national presence includes practitioners with deep expertise in software and AI patents, life sciences and pharmaceutical patent prosecution, and clean technology innovations.  

Speak with a Miller Thomson Intellectual Property lawyer about your Canadian patent strategy.