We examine the e®ect of an emission tax when the abatement good or service is supplied by an imperfectly competitive eco-industry with free entry. We show that a higher tax always increases the number of ¯rms in the eco-industry whereas it has an ambiguous e®ect on indi- vidual and total...

The welfare implications of a merger in an environment industry (i.e. the industry that supplies abatement goods and services) are considered in a Cournot-Nash context. The traditional analysis of mergers is extended in two ways. First, we examine how the environmental policy may affect the...