Exxon Mobil
But the toughest challenge that Exxon , the world's largest oil company, may be facing in recent years comes from its own ranks: A group of dissident shareholders pushing a proposal to split Exxon's chairman and chief executive positions at Wednesday's annual meeting.
Rex Tillerson currently holds both jobs.
The company recorded two of the largest-ever corporate profits in history in 2006 and 2007, but a growing group of shareholders has publicly backed the proposal, citing Exxon's lack of investments in alternative energy as their main motive.
The Rockefeller family is leading the charge, calling for a change at the top of the company that is closely tied to their famous fortune.