Professor Yossi Spiegel, PhD, and Dan Aks are visiting researchers at ZEW’s Research Department "Industrial Economics and International Management" from November 28 to December 6, 2013. Yossi Spiegel is professor for strategy, economics, and finance at the management faculty of Tel Aviv University, Israel, and ZEW Research Associate. His main research interests are industrial organisation, economics of regulation, corporate finance, and political economy. Dan Aks is research assistant at the management faculty of Tel Aviv University. During their stay, they will be collaborating with ZEW researchers on a project on vertical mergers and minority shareholdings between upstream and downstream firms.