Regarding insurance companies suing third parties for reimbursement of expenses to an insured: most US policies (a contract, in plain terms) include the assignment of subrogation rights to the insurer as a condition of the policy, and that means if the insured doesn't consent to subrogation, the insurer isn't required to pay the claim.
http://us.rd.yahoo.com/dailynews/rss/search/track+cycling/SIG=11skbmlf6/*http%3A//www.cyclingnews.com/letters/?id=2005/01-03letters
http://us.rd.yahoo.com/dailynews/rss/search/track+cycling/SIG=11skbmlf6/*http%3A//www.cyclingnews.com/letters/?id=2005/01-03letters
