4.13 Adverse Interest Exception is a legal rule that allows a person to use real estate or other property for a purpose that is contrary to the interest of the owner. This exception applies when a person acts in good faith, without knowledge of the owner's interest, and the owner's interest is not substantially impaired. There are two types of 4.13 Adverse Interest Exception: the first is a bona fide purchaser for value exception, which applies when a person purchases property in good faith without knowledge of an owner's interest; the second is an innocent tenant exception, which applies when a person leases property in good faith without knowledge of an owner's interest.