Event insurance is a specialized type of general liability insurance designed to help protect the important event that you've paid for. This specific policy usually covers claims of property damage, third-party physical injury, as well as costs associated with holding the event. 

Special event insurance can help protect you in cases where an event planner, event holder, sponsor, or the venue itself is sued for property damage, bodily injury, or other loss which is alleged to have occurred at a private event.

A business venue may require you to get this coverage and provide a certificate of insurance to prove that you’ve obtained it before the event. They don't want to have to chase you down for restitution if something goes wrong.