Dynamic oligopoly with partial cooperation and antitrust threshold

A general framework of partial cooperation and shareholding interlocks in oligopolies is first introduced, and then the best responses of the firms are determined. The monotonic dependence of the equilibrium industry output on the cooperation levels of the firms is proved. Conditions are given for the local asymptotic stability of the equilibrium which require sufficiently small speed of adjustments. Antitrust thresholds are then introduced into the model which may result in the loss of equilibrium or in the presence of multiple equilibria. The dynamic behavior of the associated dynamic models with adaptive output adjustments also becomes more complex: period-2 cycles may emerge and coexist with stationary states.