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The Shifting Tides of Merger Litigation

Posted by on Tuesday, March 13, 2018 in Essays, Volume 71, Volume 71, Number 2.



In 2015, Delaware made several important changes to its laws concerning merger litigation. These changes, which were made in response to a perception that levels of merger litigation were too high and that a substantial proportion of merger cases were not providing value, raised the bar, making it more difficult for plaintiffs to win a lawsuit challenging a merger and more difficult for plaintiffs’ counsel to collect a fee award.

We study what has happened in the courts in response to these changes. We find that the initial effect of the changes has been to decrease the volume of merger litigation, to increase the number of cases that are dismissed, and to reduce the size of attorneys’ fee awards. At the same time, we document an adaptive response by the plaintiffs’ bar. Merger cases are being filed in other state courts or in federal court, presumably in an effort to escape the application of the new Delaware rules.

This responsive adaptation offers important lessons about the entrepreneurial nature of merger litigation and the limited ability of the courts to reduce the potential for litigation abuse. In particular, we find that plaintiffs’ attorneys respond rationally to these changes by shifting their filing patterns, and that defendants respond in kind. We argue, however, that more expansive efforts to shut down merger litigation, such as through the use of fee-shifting bylaws, are premature and create too great a risk of foreclosing beneficial litigation. We also examine Delaware’s dilemma in maintaining a balance between the rights of managers and shareholders in this area.


Matthew D. Cain
Financial Economist, U.S. Securities and Exchange Commission, Division of Economic and Risk Analysis.

Jill Fisch
Perry Golkin Professor of Law, University of Pennsylvania Law School; Visiting Professor, UC Berkeley School of Law.

Steven Davidoff Solomon
Professor, UC Berkeley School of Law.

Randall S. Thomas
Professor, John S. Beasley II Chair in Law and Business, Vanderbilt Law School.