By Julius Melnitzer | February 3, 2026
“Applicant behaviour during prosecution has little bearing on PTA in most instances in Canada.” — Jeff Leuschner
Patent term adjustment (PTA)—the mechanism that extends a patent’s term beyond the usual 20-year expiry date when granting authorities have unreasonably delayed its issue—is now available in Canada, more than a quarter of a century after it was first established in the United States (US) by the American Inventors Protection Act of 1999.
The Canadian PTA regime applies to domestic patents granted on or after December 2, 2025, that have a filing date on or after December 1, 2020.
“PTA is a concession that Canada made during the negotiations for the Canada-United States-Mexico Agreement (CUSMA),” says Jeff Leuschner, a principal in the Ottawa office of Smart & Biggar, a member of the IPH network. “However, the government implemented the process in a way that meets CUSMA requirements but went no further.”
The upshot is that Canada’s approach to PTA, which focuses on overall target deadlines for patent issuance, differs significantly from that in the US.
PTA in Canada
A Canadian patent may qualify for PTA if the Canadian Intellectual Property Office (CIPO) takes longer than five years after filing or entering national phase in Canada, or three years from the date examination was requested, to issue a patent. The later of these dates is the “target issue date”. Every day beyond that target counts towards PTA. However, delays not directly attributable to CIPO are deducted, including time periods during which CIPO is waiting for the applicant to act.
“Applicant behaviour during prosecution has little bearing on PTA in most instances in Canada because each day the applicant takes to act during active substantive examination is both accrued towards PTA and subtracted from it, creating a zero effect,” Leuschner says. “What impacts PTA is, for the most part, how long CIPO takes when the application is in their court.”
In other words, Canada’s system operates on a “chess-clock” model. When CIPO issues an action, the clock stops and the applicant’s clock begins.
However, Leuschner suggests that patentees can maximize PTA opportunities by deferring examination for more than two years after the filing date or after entering national phase in Canada. The result will be that the three-year requirement for issuance will expire later than five years from the filing date/national entry date.
“Taking care of formality requirements by the original deadline, and in particular paying maintenance fees on time, will also avoid unnecessary PTA deductions”, Leuschner advises.
PTA in the United States
By contrast, the US system, in addition to requiring issuance within three years of filing, imposes deadlines on various processing steps and also takes into account delays caused by appeals, secrecy orders or interferences. From the total, the United States Patent and Trademark Office (USPTO) deducts overlapping delays and applicant delays.
The US does, however, allow for a three-month response time for processing delays. Canada does not provide any allowance for applicant responses.
From a procedural perspective, the USPTO calculates PTA and includes it in the issue notification. Canadian patentees must determine the availability themselves: if they conclude that a PTA grant is appropriate, they must apply to CIPO within three months of issuance. The application demands a standard fee of about $2500, with a lesser amount of about $1,000 for “small entities”.
Conclusion
The substantive and procedural differences between the two countries suggests that PTAs will be much rarer in Canada. Indeed, the Canadian Intellectual Property Office’s regulatory analysis impact statement expects only about 113 requests each year, which amount to a mere 0.5 percent of granted patents.
“PTA will be relatively rare in Canada because the time limits are well in excess of CIPO’s service standards,” Leuschner says. “From a procedural perspective, our process is not as patentee-friendly as the American one.”
Julius Melnitzer is a Toronto-based legal affairs writer, ghostwriter, writing coach and media trainer. Readers can reach him at julius@legalwriter.net or on his website.