Although the majority of policies are written with a claims-made coverage trigger, such coverage is sometimes available on an occurrence basis. Typical exclusions are for intentional/criminal acts, punitive damages, sexual misconduct, and specialized procedures (e.g., radial keratotomy) for which coverage may be "bought back" in return for additional premium. In addition to commercial insurers, medical malpractice coverage is also available in most states through physician-owned insurance companies known as "bedpan mutuals."