Commercial General Liability Insurance: Coverage Structure, Occurrence vs. Claims-Made, and Limits

Commercial general liability (CGL) insurance is the foundational liability coverage for virtually every business entity — from sole proprietors to Fortune 500 corporations. The ISO CGL form (CG 00 01) is the industry standard, providing three coverages: Coverage A (bodily injury and property damage liability), Coverage B (personal and advertising injury liability), and Coverage C (medical payments). Understanding the CGL’s coverage structure, trigger mechanism, limits architecture, and exclusion set is essential for any business owner, risk manager, or coverage professional building or reviewing a commercial insurance program.

For personal liability coverage under homeowner’s policies, see Personal Liability Coverage: How HO-3 Section II Protects Homeowners. For situations where CGL limits are insufficient or where umbrella coverage is needed above the CGL, see Umbrella and Excess Liability Insurance: When Primary Limits Are Not Enough.

Coverage A — Bodily Injury and Property Damage Liability

Coverage A is the core CGL coverage: it pays sums the insured becomes legally obligated to pay as damages for bodily injury or property damage caused by an occurrence that takes place in the coverage territory and during the policy period, subject to the policy exclusions. “Bodily injury” includes physical injury, sickness, disease, and death resulting from any of these. “Property damage” includes physical injury to tangible property (including resulting loss of use) and loss of use of tangible property that is not physically injured.

Definition — Occurrence (ISO CGL): An accident, including continuous or repeated exposure to substantially the same general harmful conditions, which results during the policy period in bodily injury or property damage neither expected nor intended from the standpoint of the insured. The occurrence definition distinguishes CGL from claims-made policies and is the trigger for Coverage A coverage.

The Coverage A structure includes four key damage exclusions that frequently produce coverage disputes: the “your work” exclusion (damage to the insured’s own work product — covered under contractors’ professional liability or builders risk, not CGL); the “your product” exclusion (damage to the insured’s product itself — covered under product recall or first-party property coverage); the “expected or intended injury” exclusion (intentional harm); and the “contractual liability” exclusion (liability assumed by contract, with an exception for “insured contracts” — leases of premises, sidetrack agreements, easement agreements, and tort liability assumed in construction contracts that meet specific criteria).

Coverage B — Personal and Advertising Injury Liability

Coverage B covers specified intentional torts arising from the insured’s business operations, listed exhaustively in the policy: false arrest, detention or imprisonment; malicious prosecution; wrongful eviction, entry, or invasion of right of private occupancy; written or spoken defamation (slander or libel); privacy violation through publication; use of another’s advertising idea; and copyright, trade dress, or slogan infringement in advertising. The Coverage B trigger is when the offense was “committed” — not when the occurrence happened and not when the claim was filed, creating a coverage trigger that is neither purely occurrence nor purely claims-made.

Coverage B is increasingly important for businesses with digital and social media presence. Defamation claims from negative reviews or competitive disparagement, copyright infringement claims from using stock photographs without proper licensing, and privacy violation claims from marketing data practices are all potential Coverage B triggers for standard commercial businesses. The Coverage B “intellectual property” exclusion applies to patent infringement and some copyright claims — not all IP exposure is covered under standard CGL.

Occurrence vs. Claims-Made Trigger

The occurrence trigger in the ISO CGL form — coverage based on when the injury-causing event happened rather than when the claim was filed — is the defining characteristic that distinguishes the standard CGL from claims-made liability policies (which dominate professional liability, directors and officers, and employment practices liability markets). The practical implication of the occurrence trigger: once an occurrence policy period has ended, coverage for occurrences within that period remains available indefinitely, as long as the statute of limitations has not run. A building contractor who builds a structure in 2018 under an occurrence CGL policy has that policy available to defend a structural failure claim filed in 2024, even though the 2018 policy has long expired.

Claims-made CGL policies — used in some specialty commercial segments — require both a retroactive date (the earliest occurrence date that can be covered) and active coverage at the time the claim is filed. When a claims-made policy is canceled or not renewed, an extended reporting period (ERP) endorsement — called a “tail” — must be purchased to maintain coverage for claims filed after the policy ends for occurrences during the policy period. Tail premiums are typically 150–250% of the annual policy premium for a 5-year tail, and indefinite tail coverage (covering all future claims for past occurrences) is generally available at a higher multiple.

CGL Limits Structure

The ISO CGL policy is the only standard commercial liability form with six distinct limit entries, each serving a different function. The general aggregate is the most critical limit from a risk management perspective: it is the maximum the policy pays for all Coverage A and B claims during the policy period, and it erodes with every claim payment. For a business with $1M per occurrence / $2M general aggregate limits, three $700,000 claims in a single policy period produce: first claim paid at $700,000 (leaves $1.3M aggregate), second claim paid at $1M per occurrence limit (exhausts aggregate). No further Coverage A or B coverage is available for the rest of the policy period.

The separate products-completed operations aggregate is designed specifically for contractors, manufacturers, and distributors whose completed work or sold products can produce claims long after the work is done or the product is shipped. Maintaining adequate completed operations aggregate is a critical coverage decision for any business in these categories — and a frequent source of underinsurance when businesses underestimate the long-tail nature of their completed operations exposure.

Key CGL Exclusions and Coverage Gaps

The absolute pollution exclusion — added to standard CGL forms in 1986 — excludes bodily injury and property damage arising from the discharge, dispersal, seepage, migration, release, or escape of pollutants. Courts have applied this exclusion broadly and inconsistently: some courts apply it only to traditional environmental pollutants in an environmental context; others apply it to any chemical substance including carbon monoxide, lead paint dust, pesticides, and cleaning products — effectively covering much of the chemical hazard exposure in residential and commercial operations. Businesses with chemical handling, commercial cleaning, pest control, or industrial operations need to carefully review how their state’s courts have interpreted the pollution exclusion and whether a pollution liability endorsement or standalone policy is needed.

The professional services exclusion removes coverage for liability arising from providing or failing to provide professional services — the CGL covers the premises and operations liability of a law firm (a client who slips in the lobby), but not the professional liability (a client who claims the attorney committed malpractice). Professional liability, also called errors and omissions (E&O) coverage, is a separate policy form required for any business where professional judgment, advice, or services form the core of the business activity.

Employment practices liability — covering discrimination, harassment, wrongful termination, and similar employment-related claims — is excluded from standard CGL. EPLI is a separate policy with a claims-made trigger, defense within the limit structure (unlike CGL’s defense outside the limit), and significant carrier underwriting scrutiny of the insured’s HR practices, employee handbook, and complaint handling procedures.

Frequently Asked Questions