Does an insurance exclusion for rust damage cover oil spilled from a corroded tank? S.W. Energy Corp. v. Continental Ins. Co. Explained

In S.W. Energy Corp. v. Continental Insurance Co., the Utah Supreme Court addressed whether an insurance policy exclusion for losses “caused by rust or corrosion” applies to crude oil that spilled from a tank through a hole created by rust and corrosion.

Background and Facts: S.W. Energy operated oil and gas wells in Grand County, Utah. In November 1995, one of its thirty-two-year-old oil storage tanks ruptured, spilling 495 barrels of crude oil through a two-inch hole in the tank floor. The hole had developed from rust and corrosion on the outside of the tank over a prolonged period. S.W. Energy’s insurance policy covered oil storage tanks and crude oil but excluded coverage for “loss or damage caused by rust, corrosion” and other specified conditions. The insurer denied the entire claim based on this exclusion.

Key Legal Issues: The primary issue was whether the policy exclusion applied to the lost oil when the oil itself was not rusted or corroded, but was lost due to tank damage caused by rust and corrosion. S.W. Energy argued the exclusion should only apply to “direct” losses from rust and corrosion, not “indirect” consequences like oil spillage.

Court’s Analysis and Holding: The Utah Supreme Court applied correctness review to the district court’s interpretation of the insurance policy. The court found no ambiguity in the exclusionary language, noting that “caused by” encompasses both direct and incidental damages where there is a clear causal link. The court rejected S.W. Energy’s argument that only the oil’s physical condition mattered, explaining that the exclusion covers any “loss or damage caused by” the listed conditions, not just losses “consisting of” those conditions. The court also dismissed S.W. Energy’s direct versus indirect causation argument, finding no basis in the policy language for such a distinction.

Practice Implications: This decision reinforces that Utah courts will not read artificial limitations into clear insurance policy language. The ruling also demonstrates the importance of the “fairly debatable” standard for bad faith claims—when coverage denial has a reasonable basis, insurers cannot be held liable for bad faith even if the insured disagrees with the interpretation.