Longtime shale boss and North Texas energy magnate Scott Sheffield said he’s no longer interested in joining Exxon Mobil Corp.’s board after the U.S.

Chevron won its hotly contested legal battle against rival Exxon Mobil, allowing it to immediately close its $53 billion acquisition of Hess on July 18 and give the Big Oil major access to arguably the biggest oil discovery of the century offshore of sparsely populated Guyana.