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Hedge Fund Activism

Hedge funds are engaging in a form of shareholder activism and monitoring that differs fundamentally from previous activist efforts by other institutional investors. Several studies show that when institutional investors, particularly mutual funds and pension funds, follow an activist agenda, they do not achieve significant benefits for shareholders (Karpoff (2001), Romano (2001), Black (1998), and Gillan and Starks (2007)). 

Research by Brav, Jiang, Partnoy and Thomas (2008); Klein and Zur (2008) suggested that the opposite is true of hedge funds.  Unlike mutual funds and pension funds, hedge funds may be  able to influence corporate boards and managements due to key differences arising from their different organizational form and the incentives that they face.  Hedge funds employ highly incentivized managers who manage large unregulated pools of capital.

Because they are not subject to regulation that governs mutual funds and pension funds, hedge funds can hold highly concentrated positions in small numbers of companies, and use leverage and derivatives to extend their reach. Hedge fund managers also suffer few conflicts of interest because they are not beholden to the management of the firms whose shares they hold. After the financial crisis, hedge funds have been subject to some new regulation, including limited disclosures to regulators, but those have not fundamentally altered their business. In sum, hedge funds are better positioned to act as informed monitors than other institutional investors.

Brav, Jiang, Partnoy and Thomas (2008) find that hedge fund activists tend to target companies that are typically “value” firms, with low market value relative to book value, although they are profitable with sound operating cash flows and return on assets.  Payout at these companies before intervention is lower than that of matched firms.  Target companies also have more takeover defenses and pay their CEOs considerably more than comparable companies.  Relatively few targeted companies are large-cap firms, which is not surprising given the comparatively high cost of amassing a meaningful stake in such a target.  Targets exhibit significantly higher institutional ownership and trading liquidity.  These characteristics make it easier for activists to acquire a significant stake quickly.

Clifford (2008), Brav, Jiang, Partnoy and Thomas (2008), Bebchuk, Brav and Jiang (2013), Klein and Zur (2009), and Becht, Grant and Wagner (2014), and others, suggest that hedge fund activism generates significantly higher announcement period abnormal stock returns than a control sample of passive block holders, and that hedge fund activists have achieved measurable success, at least in terms of traditional metrics such as Tobin’s Q. Bebchuk, Brav and Jiang (2013) find that hedge fund activism through 2007 was followed by improved operating performance during the post-intervention 5-year period.

Studies of the first wave of hedge fund activism suggested that activism might be in decline as the market for activism grew, competition increased, and the most viable opportunities for interventions declined. Brav, Jiang, Partnoy and Thomas (2008), for example, found that as hedge fund activism became more common, the average abnormal returns at the filing of a Schedule 13D dropped, from 15.9% in 2001 to 3.4% in 2006. However, Krishnan, Partnoy and Thomas (2016) find that top hedge fund activists were able to achieve continued success in the face of increased competition by acquiring a reputation for having the ability to pressure managers in credible ways.

The long term effects of hedge fund activism are hotly debated.  DeHann, Larcker and McClure (2018) find pre- to post activism returns are insignificantly different from zero and further find no evidence of abnormal post-activism performance improvements.  Bebchuk, Brav and Jiang (2015) argue that policy makers should not accept claims that hedge fund activism is costly to firms and their shareholders in the long term.

There is an extensive literature on hedge fund activism which is summarized in Bebchuk, Brav and Jiang (2015); Brav, Jiang and Kim (2009); Coffee and Palia (2015). The international aspects of hedge fund activism have also been explored extensively in Becht, Franks, Grant and Wagner (2015); Becht, Franks and Grant (2010).

This page is intended as a resource for issues pertaining to activism and corporate governance as examined through the disciplines of economics, business strategy, law and other areas.

Queries, suggested inclusions, and project funding proposals should be directed to Prof. Randall Thomas (




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Prof. Randall Thomas



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