You agree to reimburse your medical provider for any bills that were caused by a third party, this is called a "health insurance lien".  In other words, when you are hurt in a Personal Injury matter and end up using your health insurance for some or all of your treatment, they are entitled to get reimbursed for those expenses.  This will apply when you are not at fault for the incident that causes the injuries.  Additionally, the health insurance company is only entitled to get reimbursed for the treatments that were related to the injuries from the incident and nothing more.  If you want a better understanding, please check out the blog or the article.