The broking giant Towergate has been running a captive formation for professional indemnity claims for about a year, it has emerged.

A Towergate spokesman said: “As with any large company, when something continues to grow, you review your self-insurance.”

A captive is usually set up when a company is capable of funding its own insurance premiums and claims.

They are likely to become more popular this year as rates harden and are often are set up in foreign countries. Bermuda is the largest haven, for tax incentives, although the Towergate captive is domestic.