Brief of Professor Dmitry Karshedt as Amicus Curiae Supporting Petitioner in Oil States Energy, LLC v. Greene's Energy Group, LLC

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Petitioner Oil States Energy Services sued respondent Greene’s Energy Group in a district court on several counts, including patent infringement. Greene’s then petitioned the U.S. Patent and Trademark Office (PTO) to challenge the validity of the patent claims asserted in the litigation. The PTO cancelled the claims, and the Court of Appeals for the Federal Circuit summarily affirmed that determination. Had this Court not granted certiorari, the petitioner’s patent infringement cause of action would have been extinguished by the PTO’s decision.

The error made by the Federal Circuit in the opinions that bound the court in the instant case, and repeated by respondents in certiorari briefing, lies in the attempt to classify patents as either public or private rights in a categorical manner – that is, in isolation from any particular cause of action. This framing is improper because, under this Court’s precedents, the question whether a case involves a private right that must be adjudicated by an Article III tribunal relates to a particular legal action or claim, not the underlying privilege or property interest. Under the correct approach, which takes into account the context in which the PTO makes its invalidity decisions, the Inter Partes Review (IPR) statute at issue in this case should be held unconstitutional because it empowers an agency to resolve a claim of private right: an action for patent infringement.

The cause of action for patent infringement is a private right because it has long been recognized as a species of trespass claim by which the plaintiff typically seeks, among other remedies, monetary relief for past harm from another private party. Because of its historic characterization as a trespass, infringement has a close kinship to common-law claims that this Court has recognized as private rights that cannot be adjudicated outside Article III courts.

Invalidity is one of several, enumerated affirmative defenses that a defendant in a patent case may plead in response to an allegation of patent infringement. The IPR statute effectively removes this affirmative defense to infringement from Article III courts, and empowers the Patent Trial and Appeal Board (PTAB), an arm of the PTO, to decide it. In many cases, including one involving these very litigants, a determination of invalidity by the PTAB has extinguished parallel district court actions for patent infringement. This delegation of judicial power over such causes of action to a body that is not a part of the judiciary, and not an adjunct to an Article III court, is constitutionally forbidden by this Court’s precedents.

The IPR statute offends the doctrine of separation of powers for another, closely related reason: It effectively grants to the PTAB the power to direct that pending cases be dismissed. Although Congress can constitutionally abate extant claims by amending applicable law while the litigation is pending, Congress in this case delegated to an agency the power to extinguish a claim by adjudicating an affirmative defense in favor of a defendant. Because the PTAB here fully resolved a claim concurrently pending in a district court, it violated the rule that coordinate branches cannot direct Article III courts to dispose of specific cases in a particular way.

The doctrine of separation of powers exists in part to prevent abuses that might eventuate if claims of private rights are adjudicated outside Article III courts. By empowering the Executive Branch to resolve such disputes in the patent infringement context, the IPR statute weakens Article III safeguards of impartial adjudication, and therefore contravenes separation of powers principles.

GW Paper Series

GWU Law School Public Law Research Paper No. 2017-72; GWU Legal Studies Research Paper No. 2017-72

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