What is the term for an insurer who shares a risk that is too large to retain?

The term for an insurer who shares a risk that is too large to retain is a reinsurer. Reinsurers provide insurance to other insurance companies, allowing them to transfer portions of their risk for significant events or large claims. This process is essential as it helps primary insurers manage their risk exposure, ensuring they remain solvent and can fulfill their obligations to policyholders. By passing on some of the risks to reinsurers, primary insurers can take on more business than they would be able to otherwise, helping to stabilize the insurance market.

In this context, other terms are related but do not fit the definition as precisely. An assignee typically refers to a person to whom rights or property are transferred, not necessarily related to the transfer of insurance risks. A captive insurer is a subsidiary formed to provide insurance coverage to its parent company or companies, but it does not typically share large risks with others. A cedant is an insurance company that purchases reinsurance and transfers risks to a reinsurer. While closely related to the process of transferring risk, a cedant itself does not share risk, but instead seeks protection from a reinsurer.