Cooperative Investment, Uncertainty and Access

We investigate cooperative investment for the deployment of a new infrastructure, and how it interacts with access obligations and demand uncertainty. Co-investment increases total coverage only if service differentiation and/or cost savings from joint investment, in particular due to high uncertainty, are high. Mandated access reduces incentives for coinvestment not only through lower returns but also by the existence of the access option itself. Voluntary access provision increases infrastructure coverage but reduces social welfare by softening competition.