At the end of August, the U.S. District Court for the Southern District of Texas issued what it hoped would be the final opinion in a decade's long litigation between Exxon Mobil Corp. (Exxon) and the U.S. government over past and future cleanup costs incurred under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) to remediate Exxon's Baytown and Baton Rouge refineries and nearby chemical plants. See Exxon Mobil v. United States, Nos. H-10-2386 & H-11-1814, slip op. at 1 (S.D. Tex. Aug. 19, 2020). The facilities and chemical plants were contaminated by, among other activities, the production of war materials during World War II and the Korean War. The 113-page order and opinion following a lengthy bench trial found the United States liable to Exxon for $20.3 million. Because CERCLA allocations rarely proceed to trial, the decision has captured the attention of the legal community for the rare opportunity to observe what is most often a confidential process. In addition, the Exxon decision provides potentially responsible parties (PRPs) litigating against the government with food for thought in how to approach these complicated and fact-intensive CERCLA cost recovery actions.