A more thorough explanation:

A named-insured exclusion is a provision in an insurance policy that limits liability coverage to a named insured who was injured by another named insured under the same policy. This means that if two people are insured under the same policy and one of them causes injury to the other, the injured person may not be covered by the policy.

For example, if John and Jane are both named insureds under a car insurance policy and John causes an accident that injures Jane, the named-insured exclusion may prevent Jane from receiving coverage for her injuries.

This type of exclusion is common in liability insurance policies, such as car insurance and homeowner's insurance. It is important to read and understand the terms of your insurance policy to know what is and is not covered.