Berkley National Insurance Company has filed a new Commercial General Liability endorsement in Kansas that explicitly excludes coverage for Legionella-related losses across its General Risk Program.

The filing introduces a Legionella Exclusion that removes coverage for bodily injury, property damage, medical expenses, personal and advertising injury, and related costs arising from exposure to Legionella pneumophila or any disease associated with the bacteria, including Legionnaires’ disease. The exclusion also applies to investigation, testing, remediation, and regulatory actions tied to Legionella exposure, even when only part of a claim involves the bacteria.

The endorsement is written broadly. It applies regardless of concurrent causes, insured contracts, products-completed operations, or workplace exposure. If any portion of a claim involves Legionella, the exclusion eliminates coverage for the entire claim, even if other elements would otherwise be covered under the policy.

The filing was submitted on January 31, 2026, with a requested effective date of June 1, 2026, for both new and renewal policies. It applies to Commercial General Liability policies written by Berkley National Insurance Company and affiliated carriers within the W. R. Berkley group, including Berkley Regional, Riverport, and StarNet. No rate impact is associated with the endorsement.

The move places Legionella alongside other tightly excluded environmental and bacteria-related risks in commercial liability programs, reflecting continued underwriting caution around exposure-driven claims.