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How and When to Challenge a Patent or Patent Application in Canada

“Patent prosecution” is a term used to refer to the road that a patent application follows en route to grant or, in some cases, abandonment. In Canada, participation in this process is typically ex parte and limited to patent applicants and their representative (i.e. their patent lawyer or agent). However, in certain circumstances, third parties may make their opinions heard during patent prosecution and after grant.

Examination and Prosecution – Protests and Prior Art Submissions
Third parties can file a request for examination, or even a “special order” accelerated examination in circumstances where failure to advance the patent application prejudices the rights of the third party requester. Third parties are also generally allowed to submit prior art and other non-patentability arguments to the Patent Office, although it is up to the Examiner to determine the weight of third party submissions.

Pursuant to section 34.1 of the Patent Act, any person may submit prior art (e.g. patents, patent applications, printed publications, etc.) that may be relevant to the patentability of any claim in a pending patent application. Hence, an intervener may interfere with the patent prosecution process by providing the Examiner with arguments that could be used to reject an applicant’s patent application. The Examiner will notify the intervener and the applicant that the prior art submission has been received, but will not inform the intervener about any actions taken.

In addition to prior art submissions, one of the other few exceptions to ex parte prosecution of Canadian patent applications is the filing of protests under section 10 of the Patent Rules.  There is case law that suggests section 10 of the Patent Rules allows third parties to file a protest against the grant of a patent on the basis that the patent application contravenes section 38.2(1) of the Patent Act for adding new subject matter.[1]

Even after a notice of allowance has been issued, an Examiner has discretion to consider protests and prior art submissions, and withdraw the notice before the patent grants.

Post Grant
After the grant of a patent, a third party may request re-examination of any claim of a patent by filing prior art and paying a fee. The third party requestor must include a written submission setting forth the pertinence of the prior art in relation to the claims of the granted patent. A re-examination board will consider whether a substantial new question of patentability has been raised by the prior art submission. If the re-examination board determines that a substantial new question of patentability has been raised, the patentee may be required to narrow or cancel some of the claims in issue. This may be an attractive way to challenge a patent without resorting to litigation.

Re-examination has drawbacks, which may impact its attractiveness to third parties. For example, once a proceeding is initiated, the patentee may cancel or suggest amendments to the issued claims or submit new claims, provided the scope of the claims is not broader than that of the original patent.  The third party is unable to make further submissions with respect to the patentability of the issued claims and any amended or new claims.  Further, while the patentee has a right of appeal, the third party lacks standing to appeal.  The prior art available to the third party is also restricted.  Prior uses and sales cannot be raised.  Only patents, applications, and printed publications may be submitted for review with a request for re-examination.

In important cases, interested parties may wish to consider initiating a court proceeding to impeach an issued patent. All invalidity issues may be raised, but the interested party runs the risk of facing a counter-claim for infringement.  The significantly higher costs and longer timeline associated with an impeachment action should also be considered with experienced patent counsel when determining whether re-examination or an impeachment action is the best way forward.

Multiple avenues exist to challenge the grant of a patent in Canada in appropriate cases, whether before or after the patent is granted. Re-examination provides third parties with a cost-effective mechanism for challenging the validity of a granted patent, although a court action to impeach the patent may be preferable in appropriate cases.

[1] Pharmascience Inc. v. Commissioner of Patents et al. (1998), 85 C.P.R. (3d) 59 at 66 (FC), affirmed 5 C.P.R. (4th) 428 (FCA)

By: Jeff K. Sun and Stephanie A. Melnychuk



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