Abstract: An optimization model about the borrowing of funds within enterprise group under the control of major shareholders is set up, in which the existence, effectiveness and fairness of internal capital markets is deduced. It is found that, capital allocation optimization may result in the ideal internal capital markets, in a "win-win" situation for all parties involved in the game. While the internal capital allocation can be kept,continuous cooperation of all parties, and increasing in social welfare can be met in the internal capital markets with conflicting costs under certain conditions.A distorted capital allocation may result in the transfer of benefits type of internal capital markets, where the internal capital allocation was not sustainable, and the efficiency and fairness is compromised. Conclusions of this study provide a theoretical basis for the empirical research.

Key words: internal capital markets, controlling shareholders, capital borrowing, ownership Structure