Infringement, Experimental Use, and a Remedies Gap

Canada has no broad statutory experimental use exemption. The question is whether the use falls within the patentee's exclusive rights at all, and whether any common-law or policy exception applies.

The university's activity. Using the patented process to make samples for a durability study, with publication of results, is use of the process. It is not a sale, but making the product by the process is itself an act reserved to the patentee. So prima facie the university is using the invention.

Experimental use defence. Canadian courts have recognised a narrow experimental use exception in some circumstances, but it is not codified and its scope is uncertain. The stronger arguments are:

• The use is for research on the coating, not for commercial exploitation, and no product is sold.
• The publication may serve the public interest in scientific progress.

But the exception is narrow. If the university's study was funded by a commercial sponsor or the results were licensed to a competitor, the experimental character weakens considerably.

Practical position. A demand letter to a university is reputationally costly and legally uncertain. The better course is to investigate the funding source and any commercial tie, then decide. If the use is genuinely academic, tolerate it and monitor. If it feeds a competitor, it becomes part of the commercial infringement case.

Effect of the 2023 publication. It does not invalidate the 2021 patent; it is after grant. The competitor's argument that it "shows the process was known" is irrelevant to validity unless the publication predates the priority date, which it does not.

Import argument. The competitor is wrong. A process patent is infringed not only by using the process in Canada but also by importing a product made by the patented process, where the product is made by the process and the importation is without authority. The competitor's argument that it imports a "product, not a process" ignores the process-patent import provision. The patentee must prove the imported parts were made by the patented process - evidence can include the competitor's supplier records, product analysis, or an inference where the process is the only commercially viable route. That proof is the crux of the case.

Delay argument. Mere delay in suing does not bar an injunction in Canada. The limitation period for damages is set by provincial limitation law, typically two years from discovery of the cause of action, but the patentee can still sue for infringement occurring within the limitation period and can seek a permanent injunction going forward. Laches is a weak defence in patent cases; the competitor must show prejudice, such as investment made in reliance on the patentee's silence. A 2024 demand letter actually undercuts the delay argument because it shows the patentee asserted rights.

Remedies to seek.

• Permanent injunction against further importation and sale.
• Damages or, at the patentee's election, an accounting of profits. The election matters: damages compensate the patentee's loss; an accounting disgorges the infringer's gain. Where the patentee's own sales are hard to prove, an accounting may be better.
• Delivery up or destruction of infringing stock.
• Pre- and post-judgment interest.
• Costs.

Interlocutory relief. An interlocutory injunction is hard to obtain in Canadian patent cases because damages are usually an adequate remedy and validity is often contested. Consider a motion for a preservation order instead.