Chesapeake Energy Corp’s value has soared since its June bankruptcy filing, the U.S. judge overseeing the natural gas producer’s trial indicated, and is worth $5.13 billion, far above the shale gas pioneer’s estimate. Creditors have offered sharply different estimates of the firm’s enterprise value during its trial in U.S. bankruptcy court in Houston. Judge David Jones’s figure was $1 billion higher than the mid-point of the range recently offered by the Oklahoma company.