ExxonMobil taps Dan Ammann to lead upstream efforts with Liam Mallon about to retire
In this file photo, Dan Ammann speaks at the New York International Auto Show on 1 April 2015 while he was president of General Motors. Ammann has been named president of ExxonMobil's upstream segment after two years leading the US supermajor's low carbon division.Photo: AP/SCANPIX
