This provision states that if a loss is caused by a combination of covered and excluded events, the loss is not covered. The ACC clause applies if there is a sequential loss in which the first event sets in motion a chain of events that causes a second event to causes a loss or if the two causes of loss happen at the same time. In either case, if the ACC clause is in the policy, the loss is excluded even if an unexcluded cause of loss is the proximate cause of the damage.For example, the language of the flood exclusion in most homeowners policies is preceded with anti-concurrent cause language. This resulted in a great deal of litigation after Hurricane Katrina. In short, the ACC provision in homeowners policies basically states that there is no coverage for flood (an excluded peril) even when accompanied by wind (a covered peril). (See Storm Surge).