ToplineConocoPhillips plans to buy fellow American energy giant Marathon Oil in an all-stock deal worth a total of 22.5billion,thecompaniesannouncedWednesday,markingthelatestinastringofmultibillion−dollarmergersandacquisitionsdealsintheenergyindustry.AConocoPhillipsoilfieldinAlaskain2019.TheWashingtonPostviaGettyImagesKeyFactsTheall−stockdealvaluesMarathonOilat17.1 billion, knocking off the $5.4 billion in debt included in the total transaction value for the Hous ...