The European Commission has intensively discussed the mandatory separation of natural gas transmission from production and services. However, economic theory is ambiguous on the price effects of vertical separation. In this paper, we empirically analyse the effect of ownership unbundling of...

In summer 2005, the German telecommunication incumbent Deutsche Telekom announced its plans to build a new broadband fibre optics network. Deutsche Telekom decided as precondition for this new network not to be regulated with respect to pricing and third party access. To develop a regulator's...