Asymmetric information, signaling and environmental taxes in oligopoly

This paper examines the effects of signaling on environmental taxation in a two-period oligopoly model in which each firm privately knows whether its technology is clean or dirty, while third parties (the rival firms and the regulator) have only a subjective perception about this fact. Consequently, there are both horizontal and vertical asymmetric information, and each firm can strategically manipulate both, the competitorʹs and the regulatorʹs priors. In this context, we find that each firm wishes to be perceived as a technologically clean firm in period 2 whenever the regulatorʹs ecological conscience is sufficiently high. We also show that taxes under symmetric information are always positive, but under asymmetric information and signaling they may be negative (subsidies) and lower or greater than in the symmetric information case, depending on the ecological conscience of the regulator and the probability of firms being dirty. Finally, taxes are below environmental marginal damage, both under symmetric and asymmetric information, and signaling reinforces such under-taxation.