Known Loss Rule

The known loss rule — also called the loss in progress doctrine — holds that you cannot buy insurance for a loss that has already happened or that you already know is happening when the policy begins. It flows directly from the fortuity principle: insurance exists to transfer uncertain risk, so a claim the insured knew about at inception falls outside the coverage grant. Courts apply it even when a policy has no explicit exclusion, treating known losses as fundamentally uninsurable rather than merely excluded.

For a small-business owner, the rule is a compliance and honesty issue at renewal or when switching carriers. If you become aware of a defect, an injury, or a circumstance likely to produce a claim, you generally cannot wait, buy a new policy, and then present the loss as if it were fresh. This is especially important with claims-made policies, where applications ask whether you know of any facts that might reasonably lead to a claim — misrepresenting that knowledge can void coverage. Being candid protects you, because a properly disclosed prior circumstance may still be covered under the outgoing policy.

The practical nuance is the difference between knowing of a loss and merely being aware of general risk. Ordinary awareness that lawsuits happen in your industry does not trigger the rule; specific knowledge of an actual loss or a substantially certain one does. Timing tools like the retroactive date and continuity provisions interact with this rule to define which policy period owns a claim. When in doubt, report circumstances to your current carrier before they mature into claims, rather than assuming a future policy will pick them up.