One of the most broadly recognized evidentiary privileges is the attorney-client privilege, which shields communications between a client and an attorney made in furtherance of obtaining legal advice from discovery during litigation. The rationale behind this privilege is the need for both the attorney and the client to speak fully and candidly without fear of disclosure, “thereby promot[ing] broader public interests in the observance of the law and administration of justice.”1 While this privilege has long been recognized for licensed attorneys, there has been an open question whether a similar privilege attaches to communications between a client and a patent agent registered to practice before the United States Patent and Trademark Office (“USPTO”). That question, which has divided a number of district courts addressing the issue, has now been answered by the Federal Circuit in the affirmative, but with clear limits.

In In re Queen’s University at Kingston, Parteq Research and Development Innovations, 2015-145, the Federal Circuit took up the question of patent-agent privilege in connection with a petition for mandamus filed by Queen’s University seeking to overturn an order from the Eastern District of Texas compelling production of communications between registered, non-lawyer patent agents and employees of Queen’s University related to the prosecution of the patents-in-suit. After concluding that mandamus was an appropriate remedy, the Court began its substantive analysis of the issue with the express recognition by the Supreme Court that “the preparation and prosecution of patent applications for others constitutes the practice of law.”2 The Court then went deeper into the Supreme Court’s Sperry decision to discuss the history of Congress’s recognition and authorization of patent agents to act in matters before the USPTO. The Court then concluded that “[t]o the extent Congress has authorized non-attorney patent agents to engage in the practice of law before the Patent Office, reason and experience compel us to recognize a patent-agent privilege that is coextensive with the rights granted to patent agents by Congress.”3

Having held that a patent-agent privilege exists, the Court continued by discussing limitations on the scope of this newly recognized privilege. “Because patent agents are not attorneys, they are not authorized by the bar of any state to practice law. As such, before asserting the patent-agent privilege, litigants must take care to distinguish communications that are within the scope of activities authorized by Congress and those that are not.”4 These activities are generally governed by 37 C.F.R. § 11.5(b)(1) that defines the scope of practice of agents before the USPTO. In broad strokes, “tasks which are reasonably necessary and incident to the preparation and prosecution of patent applications and other proceedings before the Office involving a patent application or patent in which the practitioner is authorized to participate” will receive the benefit of the patent-agent privilege.5 On the other hand, “communications that are not reasonably necessary and incident to the prosecution of patents before the Patent Office fall outside the scope of the patent-agent privilege.6 Thus, communications with a patent agent that are related to litigation issues, such as non-infringement of a third-party patent, will be outside the scope of patent-agent privilege. Similarly, communications with a patent agent related to licensing or other transactions involving patents would also likely be deemed outside the scope of the patent-agent privilege.

On the issue of validity, the Court specifically noted that “communications with a patent agent who is offering an opinion on the validity of another party’s patent in contemplation of litigation” would not be privileged.7 However, since patent agents are authorized to participate in post-grant proceedings in the patent office in which the validity of issued patents are challenged, such as inter partes reviews, communications related to invalidity of third-party patents in the context of authorized patent office proceedings would likely be within the scope of the privilege. Thus, it is not merely the substantive issue at hand, but the context of the advice that may determine if the patent-agent privilege is applicable.

The newly minted patent-agent privilege affords some protection for clients who work with patent agents, but it is a limited privilege. Care must be taken to insure that any communications with patent agents are limited only to those issues that are within the scope of a patent agent’s authorized practice before the USPTO or risk having those communications deemed discoverable during litigation.


1. Upjohn Co. v. United States, 449 U.S. 383, 389 (1981).

2. Slip op. at 13-14, citing Sperry v. State of Florida ex rel. Florida Bar, 373 U.S. 379, 383 (1963).

3. Slip op. at 18, emphasis added.

4. Slip op. at 24.

5. Slip op. at 25.

6. Id.

7. Id., emphasis added.