BHP paid $12.1bn for shale at the peak — sold everything for $10.8bn

On 14 July 2011 BHP Billiton agreed to buy Petrohawk Energy Corporation, an independent US oil and gas producer, for $12.1bn in cash — buying into the US shale boom at its peak, with positions in the Eagle Ford, Haynesville and Permian basins.

The cycle turned against the buyer. On 15 January 2016 BHP announced a $7.2bn pre-tax impairment of its US shale assets — an admission, four and a half years on, of what it had paid at the top of the market.

On 26 July 2018 BHP agreed to sell all of its US onshore petroleum assets for a combined $10.8bn in cash: $10.5bn to BP's American subsidiary for Eagle Ford, Haynesville and the Permian, and $300m to Merit Energy's MMGJ Hugoton III for Fayetteville. A post-tax exceptional impairment of about $2.8bn followed in its FY2018 results. Chief executive Andrew Mackenzie called the sale consistent with the group's long-term plan to simplify and strengthen its portfolio. Petrohawk alone had cost $12.1bn; everything — Petrohawk included — came out at $10.8bn.