You might find this interesting (EIA): "Investment in shale plays in the United States totaled $133.7 billion between 2008 and 2012, as part of 73 deals. Joint ventures by foreign companies accounted for 20% of these investments. The rest of the investments were either part of outright acquisitions—such as the Australian BHP Billiton oil company's acquisition of Petrohawk Energy Corp.—or were joint ventures among American companies (such as Hess and Noble Energy with Consol Energy) and financial institutions."
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