Big Oil probably won't be buying up the Permian Basin's struggling independent drillers any time soon. : (Bloomberg) -- Big Oil probably won’t be buying up the Permian Basin’s struggling independent drillers any time soon. Years of costly exploration and frantic buying sprees have gutted shareholder returns in the world’s largest shale basin. And management teams and their financial backers can’t count on shale-hungry, cash-rich supermajors to buy them out.