Networks of Corporate Interlocking: 19621995

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 Ž nancial corporations and correspond to a period of dramatic changes in the U.S. Ž nancial markets. Given our descriptive Ž ndings, we conclude that interlocking directorates in the United States are becoming less concentrated, though by no means insigniŽ cant. Networks of Corporate Interlocking: 1962–1995 In 1913, three years before he was to be appointed to the United States Supreme Court, Louis D. Brandeis wrote, “The practice of interlocking directorates is the root of many evils. . . . Applied to rival corporations, it tends to the suppression of competition and to violation of the Sherman law. Applied to corporations which deal with each other, it tends to disloyalty . . .” (quoted in U.S. Senate, 1978:1). As the date of this quote indicates, the critique of the corporate ties formed by interlocking directorates is by no means new. However, the domestic and international context in which interlocking directorates exist and operate in the United States is qualitatively diVerent from those existing a