Gibson Dunn Secures Seventh Circuit Victory in Major Insurance Dispute
Firm News | March 20, 2026
Gibson Dunn secured a significant victory for National Union in the U.S. Court of Appeals for the Seventh Circuit in a high-profile insurance coverage dispute arising from ethylene oxide emissions in Willowbrook, Illinois. The firm’s team successfully argued that coverage for nearly 1,000 underlying lawsuits was barred by the policies’ pollution exclusion. Following a certified question to the Illinois Supreme Court — which ruled unanimously in National Union’s favor and overruled prior precedent — the Seventh Circuit held that no coverage was owed and remanded with instructions to enter judgment accordingly.
The decision is a landmark for insurance law, with broad implications for coverage disputes involving environmental pollution nationwide.
The Gibson Dunn team included partners Tom Dupree and Nick Harper and associates Aaron Hauptman and Aly Cox.