Preliminary Injunctive Relief in Patent Cases: Repairing Irreparable Harm

Texas Intellectual Property Law Journal, Vol. 31, pp. 63–130, 2022

In the wake of the US Supreme Court’s decisions in eBay v. MercExchange and Winter v. Natural Resources Defense Council, courts have applied multi-factor tests when considering whether to issue permanent and preliminary injunctions in patent cases. These tests rely heavily on the question of whether a patentee is likely to suffer “irreparable” harm if an injunction is not granted. Yet even though the meaning of irreparable harm in the context of permanent injunctions has attracted significant attention from legal commentators, there have been few analyses of the term in the preliminary injunction context.

In an article published in the Texas Intellectual Property Law Journal, Analysis Group Managing Principal John Jarosz, Principal Robert Vigil, and academic affiliate Jorge Contreras of the University of Utah S.J. Quinney College of Law remedy this omission through an analysis of data from 211 US District Court patent cases in which preliminary injunctions were sought. Based on their research, the authors propose that recognizing the specific meaning of irreparable harm – as distinct from simply “harm” – could alleviate much of the uncertainty surrounding preliminary injunctive relief.

The authors begin their examination of the issue by providing an overview of related legal precedent, including descriptions of the Winter test, which is used to assess whether a moving party is entitled to a preliminary injunction. They then detail the historical importance of defining what harm may be considered irreparable, expand on the difficulties of proving such harm, and summarize the problems associated with evaluating irreparable harm in patent cases. The authors conclude by introducing a new four-factor test to assess irreparable harm in the context of preliminary injunctions. This new test, the authors write, is an economic framework intended to “lead to economically sensible outcomes and provide consistent guidance to future litigants.”

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Read a related article in the Federal Circuit Bar Journal


Jarosz JC, Contreras JL, Vigil RL