8.3 Occurrence vs. Claims-Made Triggers

What a Coverage Trigger Does

A coverage trigger is the event that determines which policy must respond to a liability loss and whether a given policy year is on the risk. The trigger matters most for claims that surface long after the conduct that caused them, such as latent injuries from a product or pollution. The exam tests two trigger types found in Insurance Services Office (ISO) liability forms: occurrence and claims-made.

Occurrence Trigger

An occurrence policy covers losses caused by an occurrence that takes place during the policy period, no matter when the claim is finally reported. The date of injury or damage is what matters, not the date the claim is filed.

• Advantage: long-tail protection. A 2026 policy still responds to a 2026 injury reported in 2031.
• Disadvantage: insurers face uncertainty pricing late-emerging claims (the "long tail").

The standard ISO Commercial General Liability (CGL) Coverage Form CG 00 01 is available on an occurrence basis. In an occurrence form, you find the responsible policy by asking: when did the injury or damage happen?

Claims-Made Trigger

A claims-made policy covers a claim only if the claim is first made against the insured during the policy period (or extended reporting period) and the injury occurred on or after the retroactive date. Two conditions must both be met: the claim is made in the period, and the loss occurred after the retro date.

Key Claims-Made Features

Worked Scenario

A contractor buys a claims-made CGL effective 1/1/2024 with a retroactive date of 1/1/2024. An injury occurs in 2025, but the claim is first made in 2026 after the policy expired.

• If a supplemental ERP (tail) was purchased, the 2026 claim is covered because the injury followed the retro date and the tail extends reporting.
• Without any tail, the late claim is not covered, because the claim was not first made during the policy period.

If the injury had occurred in 2023 (before the retro date), the claim is excluded regardless of when it was reported.

Side-by-Side Comparison

Exam Traps

• A claims-made policy is not triggered by the injury date alone — the claim must be made during the policy period and the injury must follow the retroactive date.
• The tail (supplemental ERP) protects the insured after the claims-made policy ends; a new occurrence policy is the way to maintain seamless long-tail protection going forward.
• When an insured switches from claims-made to occurrence, buying tail coverage on the expiring claims-made form prevents a gap.

Why Triggers Exist: The Long-Tail Problem

Some liabilities surface years after the conduct that caused them — asbestos, pollution, and defective products are classic long-tail exposures. Occurrence forms create uncertainty for insurers because a single policy year can be hit by claims reported a decade later. Claims-made forms were developed to give insurers a clearer picture of their exposure by tying coverage to the reporting date.

Step Premiums and Maturity

A claims-made program typically uses step-rated premiums: the first ("first-year") policy is cheap because few claims can mature against it, and premiums rise each year until the policy is mature (usually year five). When an insured has held continuous claims-made coverage for several years, replacing it with a new first-year claims-made policy without tail coverage would create a dangerous gap.

Maintaining Seamless Coverage

Nose coverage (prior acts) does the opposite of a tail: the new insurer agrees to pick up the old retroactive date, covering occurrences before the new policy's inception so the insured avoids buying a tail.

Tail vs. Nose at a Glance

Summarize the two gap-fillers because the exam pairs them. A tail (supplemental ERP) extends the time to report claims for occurrences before a claims-made policy expired, protecting the insured looking backward after coverage ends. Nose (prior acts) coverage moves the new policy's retroactive date back to an earlier date, covering occurrences from before the new policy began. Together they keep an insured continuously protected when changing carriers or retiring, and a producer who omits either can leave a costly coverage gap.

Coverage Triggers: Occurrence vs. Claims-Made

Liability policies "respond" based on a coverage trigger, and the exam tests two main models plus their hybrids. An occurrence trigger responds when the injury or damage takes place during the policy period, regardless of when the claim is reported — ideal for long-tail (latent) exposures. A claims-made trigger responds when the claim is first made during the policy period (or an extended reporting period) for an event on or after the retroactive date.

Claims-made forms manage the timing with the retroactive date (no coverage before it) and Extended Reporting Periods (ERPs / tails): a basic tail (automatic, limited time) and a supplemental tail (purchased, often unlimited reporting). Moving between insurers, prior-acts ("nose") coverage can be granted by keeping the old retro date.

Worked scenario (long-tail): A worker is exposed to a harmful substance from 2010-2014 but the disease and lawsuit appear in 2026. Under occurrence policies, the years of exposure (2010-2014) are triggered, and those older policies respond even though the claim is decades later. Under a claims-made policy with a 2020 retro date, the same claim would be excluded because the injury predates the retro date. This contrast — occurrence anchors to when injury happened, claims-made anchors to when the claim is made plus the retro date — is one of the most heavily tested liability concepts.