One does not need to be a legal scholar to know that confidential communications between lawyers and their clients for the purpose of seeking and giving legal advice are generally privileged. The so-called “solicitor-client” privilege is a cornerstone of law and allows clients and their lawyers to freely discuss legal issues without unintended disclosures. Thus, apart from certain exceptions, Canadian courts will not compel production of privileged communications such as emails, letters and reports exchanged between clients and their lawyers for the purpose of legal advice.

For years, this special treatment did not attach to communications between clients and their patent agents. This was problematic because patent agents often provide equally strategic and sensitive advice and opinions in the specific area of patents. As a result, it was common practice to channel such communications through lawyers to shroud these under solicitor-client privilege.

In 2016, the Patent Act was amended to establish privilege for communications between a registered Canadian or foreign patent agent and their clients or client representatives. Section 16.1 of the Patent Act, entitled “Privileged Communications”, now protects communications for the purpose of seeking or giving advice with respect to any matter “…relating to the protection of an invention”.

On November 19, 2021, the Federal Court narrowly interpreted the meaning of “relating to the protection of an invention” and the scope of patent agent privilege. At issue was a document in which a patent agent provided advice to his client (employer) as to whether certain chemical compounds were outside the scope of patent rights owned by a third party. In denying privilege, the Court held that:

“Had Parliament intended to attach privilege to any and all communications between patent agents and their clients, it would have used language broader than “protection”. Instead, Parliament chose to limit patent agent privilege to a narrower class of communications.”

In the same decision, other documents were found to be under privilege because they related to the protection of the client’s patent rights. Thus, communications related to the protection of a client’s invention will generally be protected by patent agent-client privilege while communications related to a third party’s invention will not.

The take-home message from this decision is that privilege may fail to attach to some patent agent communications when providing advice that does not relate squarely to the “protection” of a client’s patent rights (e.g., non-infringement opinions and patent strategy). To attach and maintain privilege, it remains relevant to consider involving Canadian or foreign lawyers when communicating on issues outside of the “protection” of a client’s invention. Also, for privilege to attach, the communications must be intended to be confidential. Worth noting, patent agent privilege will be lost if the client expressly or implicitly waives privilege such as by disclosing documents to third parties without special precautions being put in place beforehand.