Australia’s BHP Billiton and the recently acquired Anadarko Petroleum submitted the largest dollar totals of high bids in US Gulf of Mexico Lease Sale 253. Operator Talos Energy now believes Zama’s gross recoverable resource lies in the upper half of its pre-appraisal estimate of 400–800 million BOE. The consortium is working toward a 2020 final investment decision on the project. The deal consists of stakes in nine shallow-water producing fields covering 108,000 gross acres in 10–50 m of water. The new well control rule is evidence that memories of the Macondo blowout remain a powerful force for caution.