If you currently hold a membership with one of the UK Medical Defense Organisations, it will be on what is called “an occurrence basis”.
An Occurrence policy covers professional services rendered at the time that the policy is in force, regardless of when an associated claim is made. For example, assume you had an Occurrence policy in force for the calendar year of 2011. If a claim is made today based on treatment performed on a patient in 2011, the 2011 Occurrence policy responds.
One advantage of Occurrence coverage is that the consultant receives a separate set of aggregate limits each year he/she purchases an Occurrence policy. Occurrence coverage does not end when the policy terminates; rather, the policy limits remain available to pay future claims based upon incidents that occurred during that policy period.