  In this paper, we consider a two-sided digital content market, and study
which of the two business modes, i.e., Business-to-Customer (B2C) and
Customer-to-Customer (C2C), should be selected and when it should be selected.
The considered market is managed by an intermediary, through which content
producers can sell their contents to consumers. The intermediary can select B2C
or C2C as its business mode, while the content producers and consumers are
rational agents that maximize their own utilities. The content producers are
differentiated by their content qualities. First, given the intermediary's
business mode, we show that there always exists a unique equilibrium at which
neither the content producers nor the consumers change their decisions.
Moreover, if there are a sufficiently large number of consumers, then the
decision process based on the content producers' naive expectation can reach
the unique equilibrium. Next, we show that in a market with only one
intermediary, C2C should be selected if the intermediary aims at maximizing its
profit. Then, by considering a particular scenario where the contents are not
highly substitutable, we prove that when the intermediary chooses to maximize
the social welfare, C2C should be selected if the content producers can receive
sufficient compensation for content sales, and B2C should be selected
otherwise.
