Jugando con fuego: ConocoPhillips

ConocoPhillips is the nation's second-largest refiner and third-largest American oil company overall.

This year, Mulva is spending $18 billion to finance new drilling projects, upgrade investment-starved refineries and make acquisitions, including increasing Conoco's stake in Russian oil producer Lukoil.

And growing by acquisition is getting pricey. Critics say Mulva overpaid when he bought energy giant Burlington Resources last year for $35 billion, a deal that added $19 billion in debt.

The stock sells at a significant discount to its peers