Documentos de trabajo
Eliciting Information from Interested parties in merger control
Series Documentos de Trabajo, Mayo, 2007
González Tissinetti, Aldo
This article investigates how antitrust agencies should structure the disclosing of information about e¢ ciency gains from interested parties (merging Örms, and competitors) in merger control. We analyze the particular case of a horizontal merger with danger of foreclosure, where welfare can decrease either due to insu¢ cient e¢ ciency gains (e¢ ciency defense) or due to excessive e¢ ciency gains if the competitor exits (e¢ ciency o§ense). The Örst result is that evidence from competitors is not required unless the ex-ante market shares of the merging Örms exceed a threshold. Second, we support the role of advocacy of the parties. The burden of proof for the e¢ ciency defense should rest on the insiders (merging Örms) whereas the burden of proof for the e¢ ciency o§ense should rest on outsiders (competitors). Finally, it is optimal to make insiders report Örst and outsiders second and any communication among parties has to be prohibited.