  As complex networks in economics, we consider Japanese shareholding networks
as they existed in 1985, 1990, 1995, 2000, 2002, and 2003. In this study, we
use as data lists of shareholders for companies listed on the stock market or
on the over-the-counter market. The lengths of the shareholder lists vary with
the companies, and we use lists for the top 20 shareholders. We represent these
shareholding networks as a directed graph by drawing arrows from shareholders
to stock corporations. Consequently, the distribution of incoming edges has an
upper bound, while that of outgoing edges has no bound. This representation
shows that for all years the distributions of outgoing degrees can be well
explained by the power law function with an exponential tail. The exponent
depends on the year and the country, while the power law shape is maintained
universally. We show that the exponent strongly correlates with the long-term
shareholding rate and the cross-shareholding rate.
