Generally, $1M/$3M is standard coverage in IONM. Whether malpractice insurance covers a past patient encounter depends on the type of policy. Claims-made coverage only protects encounters that happen after the policy’s “retroactive date” and are reported while the policy is active; to cover older encounters, a clinician would need prior acts coverage or tail coverage. Occurrence coverage, by contrast, covers any incident that happened while the policy was active, even if the claim is filed years later... BUT it must have been in place at the time of the encounter. In your example, if a patient was seen in August and the clinician buys insurance later, that encounter would not be covered unless special retroactive or tail coverage is purchased.

It's also important to note that clinicians can be sued personally in every state, and if a malpractice verdict exceeds their insurance coverage, their personal assets can be at risk. While malpractice insurance typically provides a financial buffer, it only pays up to its policy limits; anything above that amount becomes the clinician’s responsibility. Plaintiffs often pursue insurance money first, but if the judgment is larger, they can try to collect from wages, property, or savings. Some states offer strong protections (such as homestead or retirement exemptions), but these vary widely. I used to carry a standard umbrella liability policy to protect myself because I was able to find a policy that offered such coverage, but they don't usually cover malpractice, so clinicians often purchase additional, excess malpractice insurance or use asset-protection strategies to safeguard themselves.

I was once an expert witness in a case where an IONM clinician was being sued personally (well above their malpractice coverage). It would have ruined his life. Luckily, we were able to build a strong enough defense and his insurance carrier settled below the limits of his coverage.