Highly read on plosone.org 15 Nov–15 Dec

The global economy is dominated by a small, tight-knit group of companies, according to a network analysis of 43,060 transnational corporations.

Credit: PLoS ONE

Stefano Battiston and his colleagues at the Swiss Federal Institute of Technology, Zurich, studied the linkages of control among these companies, where control is shareholding and ownership. The links form a structure that resembles a bow tie, similar to the structure formed when mapping all links on the World Wide Web. The knot of the bow tie — a group of intricately interlinked companies that essentially hold a majority share of one another (pictured) — is both surprisingly small and exceptionally powerful. The top 737 companies exert 80% of the control over the value of the entire network. Most of these companies are financial institutions. Barclays controls the greatest share of the network, at 4%.

The dense linkages at the bow tie's knot, the authors suggest, both protect the companies from market competition and make them prone to contagion during financial crises. The period's grim global economic news might help to explain the paper's popularity.

PLoS ONE 6, e25995 (2011)