The Porter hypothesis and the pollution haven hypothesis seem to predict opposite reactions by firms facing environmental regulation, as the first invokes the arising of a win–win solution while the second envisages the possibility for firms to flee abroad. We illustrate the possibility of designing policies (taking the form of either emission taxation or environmental standards) able to eliminate firms’ incentives to relocate their plants abroad and create a parallel incentive for them to deliver a win–win solution by investing either in replacement technologies under emission taxation, or in abatement technologies under an environmental standard. This is worked out in a Cournot supergame in which firms may activate the highest level of collusion compatible with their intertemporal preferences.

波特假说和污染天堂假说似乎预测了面临环境监管的企业的相反反应，因为前者提出了双赢解决方案的产生，而后者则设想了企业逃往国外的可能性。我们说明了设计政策的可能性（采取排放税或环境标准的形式），这些政策能够消除企业将工厂迁往国外的动机，并通过投资替代技术来创造双赢解决方案的并行动机。排放税或环境标准的减排技术。这是在古诺（Cournot）超级游戏中解决的，在这种游戏中，公司可能会激活与他们的跨期偏好相适应的最高级别的合谋。