Networks of Corporate Interlocking: 1962—1995

Abstract

This paper documents the changing patterns of corporate interlocking among approximately 250 corporations across four time periods—1962, 1973, 1983, and 1995. By utilizing network analyses, we describe several attributes of the overall set of interlocking corporate directors in a period of increasing corporate concentration, economic globalization, and changing regulatory environments. Measures of network density are based on all corporations and are broken-down by the ties formed by single versus multiple interlocking directorates. Three measures of network centralization are based on complete sociomatricies in which all ties between corporations are non-directional and have been recorded as either present or absent. Finally, we report the number of cliques formed by minimum size across time. Measures of network density, centralization and the number of cliques all underscore that the network of corporate ties in 1995 is less dense, less concentrated, and contain few subgroups. Our analyses at the corporate level demonstrate that these changes occurred primarily among financial corporations and correspond to a period of dramatic changes in the U.S. financial markets. Given our descriptive findings, we conclude that interlocking directorates in the United States are becoming less concentrated, though by no means insignificant.