8.3 Occurrence vs. Claims-Made Triggers
Key Takeaways
- An occurrence trigger responds when bodily injury or property damage happens during the policy period, regardless of when the claim is reported
- A claims-made trigger responds when the claim is first made during the policy period and the injury occurred on or after the retroactive date
- Claims-made coverage requires tracking three dates: retroactive date, policy period, and Extended Reporting Period (tail)
- ISO Basic ERP provides a 60-day automatic tail plus a five-year mini-tail; Supplemental ERP can provide unlimited reporting
- Switching from claims-made to occurrence without buying tail coverage creates a dangerous gap for old injuries reported later
Imagine a defective valve installed in 2018 fails silently, and the first lawsuit arrives in 2026. Which policy pays? The answer depends on the coverage trigger — the event that activates coverage. Triggers are among the highest-value topics on the national casualty portion of the Nevada P&C exam because they explain why two businesses with identical limits can have wildly different protection when they change carriers or policy forms.
What a Trigger Does
A coverage trigger determines which policy responds when the wrongful act and the claim fall in different years. The ISO standard Commercial General Liability program offers:
- Occurrence form (CG 00 01) — the default CGL for most commercial accounts
- Claims-made form (CG 00 02) — common for professional liability, directors and officers, and employment practices
Professional lines (malpractice, E&O, D&O, EPLI) are overwhelmingly claims-made. Sudden BI/PD businesses often carry occurrence CGL.
Occurrence vs. Claims-Made
| Feature | Occurrence | Claims-Made |
|---|---|---|
| Trigger event | BI or PD occurs during policy period | Claim first made during policy period |
| Best for | Sudden, identifiable accidents | Long-tail losses with delayed discovery |
| Retroactive date | Not used | Critical — bars pre-date injuries |
| Tail (ERP) needed? | Generally no | Yes when coverage ends or form changes |
| Premium pattern | Relatively stable year to year | Low early years, rising toward "mature" cost |
Long-tail trap: Product harm in 2019 sued in 2026 is covered by the 2019 occurrence policy in force when injury happened — not the 2026 policy, even if that is when the attorney's letter arrives.
The Three Claims-Made Dates
Claims-made policies live or die on a timeline. Work dates in order on every exam question.
- Retroactive date — earliest date of injury the policy will cover. Injury before this date is excluded forever, even if the claim is made during the current term. A policy with retro date equal to inception is the most restrictive ("no prior acts").
- Policy period — the claim must be first made against the insured (or reported per policy terms) during this window.
- Extended Reporting Period (ERP / "tail") — extends the time to report claims after policy expiration for injuries that occurred while coverage was in force.
ISO ERP Options
- Basic ERP (automatic): Includes a 60-day automatic reporting period after expiration, plus a five-year mini-tail for certain occurrences reported during the policy term.
- Supplemental ERP (purchased, often within 60 days of expiration): Can provide an unlimited reporting period — essential when a claims-made insured retires, sells the practice, or switches to occurrence coverage.
Worked Timeline: Physician Example
Policy: retroactive date January 1, 2022; policy period calendar year 2025.
| Event | Covered? | Why |
|---|---|---|
| Treatment injury December 2021, claim 2025 | No | Injury predates retro date |
| Injury March 2023, claim August 2025 | Yes | Injury on/after retro; claim in policy period |
| Injury March 2023, claim 2028, no tail | No | Claim not made during period; no ERP |
| Same facts with Supplemental ERP | Yes | Unlimited tail extends reporting window |
Rule of thumb: Claims-made needs a qualifying injury date AND a qualifying claim/report date (including tail).
Renewal and Form-Change Gaps
Producer errors cluster at renewal:
| Transition | Risk | Solution |
|---|---|---|
| Occurrence → claims-made | Lower — old occurrence policies still cover old injuries | Match retro date to prior coverage |
| Claims-made → occurrence | High — old injuries reported after expiration | Buy Supplemental ERP on expiring policy |
| Claims-made carrier A → carrier B | Gap if new retro date is later | Prior acts / matching retro date |
Failing to advise a Las Vegas medical clinic to purchase tail when its claims-made malpractice expires is a textbook producer E&O claim — the national exam references this pattern even though Nevada-specific producer rules appear in later chapters.
Step Pricing and Maturity
Because a first-year claims-made policy can only be hit by claims reported that year for recent injuries, premiums start low and step up annually until mature (often year five), when pricing approaches occurrence levels.
| Policy Year | Label | Relative Premium | Reason |
|---|---|---|---|
| 1 | First-year / Step 1 | Lowest | Only one injury year can mature into claims |
| 2–4 | Maturing | Rising | More prior injury years exposed |
| 5+ | Mature | Near occurrence | Full backlog reportable |
Letting a mature claims-made policy lapse without tail wastes years of premium — injuries from earlier years may become uninsured when reported later.
Occurrence Policies and Continuous Injury
When injury is continuous or repeated — asbestos, pollution, repetitive stress — courts apply competing trigger theories for occurrence policies:
- Exposure trigger — policy when exposure began
- Manifestation trigger — policy when injury became apparent
- Continuous trigger — multiple policies across the exposure timeline, sometimes sharing pro rata
You will not litigate these on the licensing exam, but recognizing that occurrence ties to when injury happened explains the separate products-completed operations aggregate on the CGL — insurers cap long-tail product exposure apart from ongoing operations.
Occurrence on the Nevada Exam
Fact patterns usually give you years and ask which policy responds, whether a retro date bars coverage, or whether tail was needed. Draw a simple timeline before you read answer choices. If the stem says claims-made, check retro date first, then claim date, then whether an ERP exists. If it says occurrence, ask only when injury occurred.
Three-date mantra for claims-made: retro · policy period · tail.
A manufacturing defect causes bodily injury in 2020, but the victim does not file suit until 2027. The insured carried ISO occurrence CGL continuously. Which policy responds?
On a claims-made professional liability policy, the retroactive date primarily:
An insured has carried claims-made CGL for five years and will switch to occurrence coverage with a new insurer. To avoid a gap for old injuries reported after expiration, the producer should recommend:
Why does a first-year claims-made policy typically cost less than a mature claims-made or occurrence policy?