The antitrust industry never sleeps – it is always hard at work seeking new business practices to scrutinize, eagerly latching on to any novel theory of anticompetitive harm that holds out the prospect of future investigations.  In so doing, antitrust entrepreneurs choose, of course, to ignore Nobel Laureate Ronald Coase’s warning that “[i]f an economist finds something . . . that he does not understand, he looks for a monopoly explanation.  And as in this field we are rather ignorant, the number of ununderstandable practices tends to be rather large, and the reliance on monopoly explanations frequent.”  Ambitious antitrusters also generally appear oblivious to the fact that since antitrust is an administrative system subject to substantial error and transaction costs in application (see here), decision theory counsels that enforcers should proceed with great caution before adopting novel untested theories of competitive harm.

The latest example of this regrettable phenomenon is the popular new theory that institutional investors’ common ownership of minority shares in competing firms may pose serious threats to vigorous market competition (see here, for example).  If such investors’ shareholdings are insufficient to control or substantially influence the strategies employed by the competing firms, what is the precise mechanism by which this occurs?  At the very least, this question should give enforcers pause (and cause them to carefully examine both the theoretical and empirical underpinnings of the common ownership story) before they charge ahead as knights errant seeking to vanquish new financial foes.  Yet it appears that at least some antitrust enforcers have been wasting no time in seeking to factor common ownership concerns into their modes of analysis.  (For example, The European Commission in at least one case presented a modified Herfindahl-Hirschman Index (MHHI) analysis to account for the effects of common shareholding by institutional investors, as part of a statement of objections to a proposed merger, see here.)

A recent draft paper by Bates White economists Daniel P. O’Brien and Keith Waehrer raises major questions about recent much heralded research (reported in three studies dealing with executive compensation, airlines, and banking) that has been cited to raise concerns about common minority shareholdings’ effects on competition.  The draft paper’s abstract argues that the theory underlying these concerns is insufficiently developed, and that there are serious statistical flaws in the empirical work that purports to show a relationship between price and common ownership:

“Recent empirical research purports to show that common ownership by institutional investors harms competition even when all financial holdings are minority interests. This research has received a great deal of attention, leading to both calls for and actual changes in antitrust policy. This paper examines the research on this subject to date and finds that its conclusions regarding the effects of minority shareholdings on competition are not well established. Without prejudging what more rigorous empirical work might show, we conclude that researchers and policy authorities are getting well ahead of themselves in drawing policy conclusions from the research to date. The theory of partial ownership does not yield a specific relationship between price and the MHHI. In addition, the key explanatory variable in the emerging research – the MHHI – is an endogenous measure of concentration that depends on both common ownership and market shares. Factors other than common ownership affect both price and the MHHI, so the relationship between price and the MHHI need not reflect the relationship between price and common ownership. Thus, regressions of price on the MHHI are likely to show a relationship even if common ownership has no actual causal effect on price. The instrumental variable approaches employed in this literature are not sufficient to remedy this issue. We explain these points with reference to the economic theory of partial ownership and suggest avenues for further research.”

In addition to pinpointing deficiencies in existing research, O’Brien and Waehrer also summarize serious negative implications for the financial sector that could stem from the aggressive antitrust pursuit of partial ownership for the financial sector – a new approach that would be at odds with longstanding antitrust practice (footnote citations deleted):

“While it is widely accepted that common ownership can have anticompetitive effects when the owners have control over at least one of the firms they own (a complete merger is a special case), antitrust authorities historically have taken limited interest in common ownership by minority shareholders whose control seems to be limited to voting rights. Thus, if the empirical findings and conclusions in the emerging research are correct and robust, they could have dramatic implications for the antitrust analysis of mergers and acquisitions. The findings could be interpreted to suggest that antitrust authorities should scrutinize not only situations in which a common owner of competing firms control at least one of the entities it owns, but also situations in which all of the common owner’s shareholdings are small minority positions. As [previously] noted, . . . such a policy shift is already occurring.

Institutional investors (e.g., mutual funds) frequently take positions in multiple firms in an industry in order to offer diversified portfolios to retail investors at low transaction costs. A change in antitrust or regulatory policy toward these investments could have significant negative implications for the types of investments currently available to retail investors. In particular, a recent proposal to step up antitrust enforcement in this area would seem to require significant changes to the size or composition of many investment funds that are currently offered.

Given the potential policy implications of this research and the less than obvious connections between small minority ownership interests and anticompetitive price effects, it is important to be particularly confident in the analysis and empirical findings before drawing strong policy conclusions. In our view, this requires a valid empirical test that permits causal inferences about the effects of common ownership on price. In addition, the empirical findings and their interpretation should be consistent with the observed behavior of firms and investors in the economic and legal environments in which they operate.

We find that the airline, banking, and compensation papers [that deal with minority shareholding] fall short of these criteria.”

In sum, at the very least, a substantial amount of further work is called for before significant enforcement resources are directed to common minority shareholder investigations, lest competitively non-problematic investment holdings be chilled.  More generally, the trendy antitrust pursuit of common minority shareholdings threatens to interfere inappropriately in investment decisions of institutional investors and thereby undermine efficiency.  Given the great significance of institutional investment for vibrant capital markets and a growing, dynamic economy, the negative economic welfare consequences of such unwarranted meddling would likely swamp any benefits that might accrue from an occasional meritorious prosecution.  One may hope that the Trump Administration will seriously weigh those potential consequences as it examines the minority shareholding issue, in deciding upon its antitrust policy priorities.