8.3 Occurrence vs. Claims-Made Triggers
Key Takeaways
- An occurrence form covers injury or damage that takes place during the policy period, no matter when the claim is reported; a claims-made form covers claims first made during the policy period.
- Claims-made forms use a retroactive date — injury before that date is never covered, even if the claim is made during the policy period.
- The ISO claims-made CGL (CG 00 02 04 13) adds Basic and Supplemental Extended Reporting Periods (tail coverage); the occurrence CGL is CG 00 01 04 13.
- Extended Reporting Periods extend the time to REPORT claims — they do not extend the policy limits or cover new injury.
- Long-tail exposures (professional liability, products, pollution) favor claims-made because the insurer can reserve and price more accurately.
Two Ways a Liability Policy Is Triggered
The coverage trigger decides which policy responds to a loss. There are two:
- Occurrence trigger — covers bodily injury or property damage that takes place during the policy period, regardless of when the claim is filed. The ISO occurrence CGL is CG 00 01 04 13.
- Claims-made trigger — covers claims first made (reported) during the policy period, provided the injury happened on or after the retroactive date. The ISO claims-made CGL is CG 00 02 04 13.
A classic exam scenario: asbestos installed in 2010 causes illness diagnosed in 2026. Under an occurrence policy, the 2010 policy (when injury began) responds. Under a claims-made policy, the 2026 policy responds — if the retroactive date predates 2010.
Occurrence vs. Claims-Made at a Glance
| Feature | Occurrence | Claims-Made |
|---|---|---|
| Trigger | Injury/damage during policy period | Claim first made during policy period |
| Retroactive date | None | Yes — injury before it is excluded |
| Tail / Extended Reporting Period | Not needed | Available (Basic + Supplemental ERP) |
| Best for | Short-tail (premises, auto) | Long-tail (professional, products, pollution) |
| Stacking limits | Possible across years | Single policy responds |
The retroactive date is the single most-tested claims-made feature: an injury that occurs before the retro date is never covered, even if the claim is reported during an active policy period.
Extended Reporting Periods (Tail Coverage)
When a claims-made policy is cancelled or not renewed, Extended Reporting Periods (ERPs) preserve the right to report later claims for injury that occurred during the expired policy:
- Basic ERP — automatic, usually a 60-day window to report claims for known incidents plus a longer (often 5-year) window for incidents reported during the policy. No extra premium.
- Supplemental (Full) ERP — purchased for an additional premium, often unlimited in duration. Must be requested within 60 days of termination.
Trap: an ERP extends the reporting window only — it does not restore or add new limits, and it does not cover injury occurring after the policy ends. New occurrences need a new policy.
Why Insurers Choose Claims-Made for Long-Tail Risks
Long-tail exposures — medical malpractice, products liability, environmental pollution — can surface claims decades after the injury. Under occurrence forms the insurer must reserve for unknown future claims against old policy years, which makes pricing difficult ('the long tail'). Claims-made forms let the insurer match each year's premium to claims reported that year, improving reserving accuracy. Step rating typically raises the premium in years 1–5 as the 'mature' exposure builds, after which it levels off.
A claims-made CGL has a retroactive date of January 1, 2024. An injury occurred in 2023 but the claim is first reported in 2026 while the policy is in force. Is the claim covered?
Which statement about an Extended Reporting Period (tail) is correct?
Two Coverage Triggers Compared
Liability policies are triggered in one of two ways. An occurrence policy covers bodily injury or property damage that takes place during the policy period, regardless of when the claim is later made, even years after the policy expires. A claims-made policy covers claims first made against the insured during the policy period (or any extended reporting period), provided the injury occurred on or after the retroactive date. The trigger determines which policy year answers a loss, and confusing the two is the most common error on liability-trigger questions.
The Retroactive Date and Why It Matters
A claims-made policy uses a retroactive date to exclude injuries that occurred before that date even if the claim is made during the policy period. Advancing or losing the retroactive date when switching insurers can create a coverage gap for prior acts, so maintaining the original retroactive date on renewal is essential. A scenario in which an insured switches carriers and the new policy carries a later retroactive date is signaling a gap for claims arising from earlier work, a classic claims-made trap.
Extended Reporting Periods (Tail Coverage)
Because claims-made coverage ends when the policy ends, an insured who cancels or switches needs an Extended Reporting Period (tail) to cover claims made after expiration for injuries that occurred during the policy period and after the retroactive date. A Basic ERP provides a short automatic mini-tail (often 30 to 60 days for any claim, and up to several years for claims from reported circumstances), while a Supplemental ERP, purchased for additional premium, extends the reporting window, sometimes unlimited in time. Retiring professionals frequently buy tail coverage to protect against late-emerging claims.
Why Long-Tail Risks Use Claims-Made
Insurers prefer claims-made for long-tail exposures, those where injury may not manifest or be discovered for years, such as professional liability, products with latent defects, pollution, and medical malpractice, because claims-made lets the insurer know its exposure is limited to claims reported during the period rather than open-ended occurrence exposure stretching decades into the future. Occurrence coverage remains common for general liability with shorter tails.
Recognizing that a long-tail, slow-to-manifest exposure points to claims-made coverage, and that an immediate, obvious injury fits occurrence coverage, helps you predict the policy form a scenario describes.
Reporting Provisions and Late-Notice Consequences
Both trigger types impose notice duties, but the consequence of late notice differs. Under an occurrence policy, late notice may be excused if the insurer is not prejudiced, because the coverage trigger was the injury, not the report.
Under a claims-made-and-reported policy, timely reporting can itself be a coverage condition, so a claim reported after the policy period (and outside any extended reporting period) may not be covered even though it was first made during the period. The exam tests this distinction by describing a delayed report and asking whether coverage survives, which turns on the trigger type.