This study investigated the human network that was formed through relationships between community sports clubs (CSC) and information network support NPOs (NPO) for formation of social capital, focusing on the relationships that enabled NPOs of CSCs to receive donations from CSCs across Japan after the Great East Japan Earthquake. The study analyzed 45 CSCs that had made donations to NPOs, which had conducted support projects for earthquake-stricken CSCs over a two-year period from April 2011 to March 2013. For this analysis, the period of about 13 years from 1998, when the NPOs were established, to 2011, when the earthquake occurred, was divided into 3 phases, and the requirements for social capital formed in each phase were analyzed. The following 4 concepts were used as the frame of analysis: double contingency, a key concept in Niklas Luhmann’s theory of social systems; Robert D. Putnam’s bridging social capital; and Misumi’s cognitive base and net base.
The following features were found: (1) Social capital shared the philosophy of CSCs, which was published by sport administrative agencies and the Japan Sport Association (JASA), with CSCs as a cognitive base obtained through the internet tools of NPOs; (2) The relationships between NPOs and CSCs constituted a double contingency, namely a network of uncertainty where one party cannot anticipate the behavior of the other party; (3) Individual relationships between similar CSCs constituted a net base for the connection (same type) network; and (4) the CSC, which had played a central role in the bridging network that connected the various CSCs, formed bridging social capital. Thus, NPOs that used internet tools formed the requirements for social capital through the aforementioned 4 processes.