Quick Answer: A waiver is the voluntary relinquishment or surrender of some known right or privilege. A waiver is often written, such as a disclaimer that has been accepted, but it may also be spoken between two or more parties. When the right to hold a person liable through a lawsuit is waived, the waiver may be called an exculpatory clause, liability waiver, legal release, or hold harmless clause. In some cases, parties may sign a "non-waiver" contract which specifies that no rights are waived, particularly if a person's actions may suggest that rights are being waived. This is particularly common in insurance. Sometimes the elements of "voluntary" and "known" are established by a legal fiction. In this case, one is presumed to know one's rights and that those rights are voluntarily relinquished if not asserted at the time. In the United States, regulatory agencies of state departments or the federal government may issue waivers to exempt companies from certain regulations.