Entry deterrence in a unionized oligopoly

We investigate wage determination between an incumbent firm and its labour union under threat from another firm entering its product market. In equilibrium, it may be optimal for a labour union of the incumbent firm to lower its wage demand. This may make it possible for the incumbent firm to maintain a higher employment level, in that the lower wages can help the firm deter the entry of a rival firm. This will yield a higher profit for the incumbent firm and a lower utility level for the labour union compared with those in an equilibrium with no threat of entry.