Glossary

Anti-concurrent causation clause

Exclusion wording that denies a loss whenever an excluded cause contributes, even if a covered cause also played a part or came first.

Also called: ACC clause, anti-concurrent cause clause, regardless of any other cause clause

An anti-concurrent causation (ACC) clause is lead-in wording that says an exclusion applies regardless of any other cause that contributed to the loss, whether at the same time or in any sequence. In the ISO homeowners form it introduces the Section I exclusions for ordinance or law, earth movement, water, power failure, neglect, war, nuclear hazard, intentional loss and governmental action.

The clause is aimed at concurrent causation arguments. Without it, a court might find coverage because a covered cause, such as wind, helped produce the loss. With it, the excluded cause controls. Say a hurricane's surge floods your home while wind-driven rain also damages the ceilings (hypothetical). Under ACC wording the flood exclusion applies to the flood damage even though wind contributed, while wind damage that happened independently remains covered.

Enforceability varies. Many states enforce these clauses as written, and a few, California the best known, do not allow them to override the efficient proximate cause rule. Because the outcome hinges on the exact wording and your state's law, ask the agent which exclusions in your policy carry the clause and read them before storm season. For specifics on a denied claim, consult an attorney or your state insurance department. The guide anti-concurrent causation clauses explained goes into more depth.

Last reviewed October 10, 2026

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Related terms

Concurrent causation The question of how to decide coverage when a covered cause and an excluded cause combine to produce one loss, such as wind and storm surge in a hurricane. Efficient proximate cause A legal test that decides coverage by asking which cause set the others in motion and dominated the loss when covered and excluded causes combine. Exclusion A policy provision that removes coverage for a stated cause, type of loss, property or circumstance that the coverage would otherwise reach. Earth movement A group of ground-shifting events, including earthquake, landslide, mudflow, subsidence and sinkhole, that homeowners policies exclude from coverage. Flood exclusion The standard homeowners provision that excludes flood, surface water, tides and overflowing water bodies, leaving flood damage to a separate flood policy. Storm surge The abnormal rise of seawater that a hurricane or strong storm pushes onshore above the normal tide, treated as flood and excluded from homeowners policies.

Related guides

Anti-concurrent causation clauses explained One policy sentence can bar a whole loss if an excluded cause like flood played any part. How it works, which states limit it, and how to document a claim. Does homeowners insurance cover flooding? No. A standard homeowners policy excludes flood, surface water and storm surge. Flood coverage takes a separate NFIP or private flood policy. The earth movement exclusion explained What the HO-3 earth movement exclusion removes, what it leaves covered, how it differs from settling and flood exclusions, and how to challenge a denial. Engineering reports and causation disputes When insurers and homeowners hire engineers, what causation reports contain, how to challenge one, and how to commission your own in a disputed home claim. Foundation cracks and settling: what's covered A standard homeowners policy excludes settling, soil movement and water pressure, so cause decides whether foundation damage is paid. What is covered. Hurricane coverage: wind, flood and storm surge A standard homeowners policy pays for hurricane wind damage but not for flood or storm surge. What each policy covers, where the gaps are and what to check.