Force majeure

 or vis major (Latin) "superior force", also known as cas fortuit (French) or casus fortuitus (Latin) "chance occurrence, unavoidable accident",^[2] is a common clause in contracts that essentially frees both parties from liability or obligation when an extraordinary event or circumstance beyond the control of the parties, such as a war, strike, riot, crime, or an event described by the legal term act of God (such as hurricane, flooding,earthquake, volcanic eruption, etc.), prevents one or both parties from fulfilling their obligations under the contract. In practice, most force majeure clauses do not excuse a party's nonperformance entirely, but only suspend it for the duration of the force majeure. ^[3][4]

However, force majeure is not intended to excuse negligence or other malfeasance of a party, as where non-performance is caused by the usual and natural consequences of external forces (for example, predicted rain stops an outdoor event), or where the intervening circumstances are specifically contemplated.

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