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Mass arbitration has sent shock waves through the civil justice system and unnerved the defense bar. To see how quickly and dramatically this phenomenon has entered both the civil justice landscape and the public discourse, one need look no further than the January 2023 filings of hundreds of individual arbitration demands by former Twitter employees against Elon Musk, along with threats to file hundreds more—threats that were announced, no doubt intentionally, on Twitter itself. Plaintiffs are increasingly more aware of mass arbitration as a tool in their arsenal, and defendants are, perhaps for the first time in decades of mandatory arbitration warfare, on the defensive.

From 2018 to 2021, I conducted a large study of this relatively new phenomena and published the results. In Mass Arbitration, the first and only case study of the phenomenon, I detailed the history of mandatory arbitration warfare, whereby a coalition of defense-side interests waged a decades-long effort to retrench aggregate dispute resolution through arbitration agreements and class-action waivers imposed in contracts of adhesion. This mandatory arbitration warfare achieved nothing short of an arbitration revolution—it eliminated scores of legal claims across the civil landscape and saved corporations billions of dollars. Yet, just when everyone expected the defense interests to take a victory lap, prominent defendants started to abandon the hard-fought war against class actions and, instead, began to take refuge in them. The study chronicled the genesis of mass arbitration, the transformation of mandatory arbitration from a windfall for defendants to a weapon for the plaintiffs’ bar. Mass Arbitration concluded by capturing early responses from the defense coalition and offered predictions for the future of mass arbitration.

This Article updates and expands the original study of Mass Arbitration. Of course, mass arbitration is constantly evolving. Neither the initial study nor an updated analysis in 2023 here mean that investigation and study is complete. However, as with the initial study, this Article provides important snapshots of what is now one of the most substantial developments in the civil justice landscape.

Part I of this Article summarizes the rise of mandatory arbitration, the emergence of mass arbitration, and what my prior study identified as the key elements of the mass arbitration model. Part II updates and expands on the original study, with a particular focus on responses to the phenomenon that have emerged. Specifically, Part II catalogs and briefly analyzes an array of responses to mass arbitration that have arisen in the past two years—both those that were anticipated in the Mass Arbitration study and those unanticipated. Part III takes a step back and considers who, so far, can be described as “winners” and “losers” in the mass arbitration landscape. Among other things, taking this step back reveals arbitration warfare’s arbitrariness, which has important implications for claiming by way of mandatory arbitration in particular and in our civil justice system more generally.

Publication Citation

Washington University Law Review, Vol. 100, No. 6, 1617-1651.