Language commonly included in the insuring agreement of a liability policy that stipulates that the policy does not apply to losses of which the insured was aware prior to the policy period. In some policies, this restriction appears in the exclusions section of the policy. Some policies go a step further, stipulating that where the insurer has issued successive policies, the only policy that will apply is the one in force when the insured first becomes aware of the loss. The difference in these two types of provisions is most dramatic when progressive injury or damage goes undetected over multiple policy periods.
Definition provided by the International Risk Management Institute (IRMI) Glossary of Insurance.
