Thomas Cook is one of Britain's best known tour operators, and is a public limited company - listed on the London Stock Exchange.
Thomas Cook offers travel insurance, which is a logical step to add on to its travel agency activities, which is underwritten by an Irish insurance company called White Horse Insurance. However, White Horse Insurance is wholly owned by Thomas Cook.
Because the insurer is based in Ireland, you won't have recourse to the UK Financial Ombudsman Service if you want to escalate a complaint against it.
An industry average has been used for its complaints score, as the data does not show up in the Irish Financial Ombudsman, and it didn't provide this data directly.