The Fifth Circuit considered the impact on coverage when an anti-concurrent causation clause seems to be contradicted by a "reverse" anti-concurrent causation clause in an endorsement.  See Penthouse Owners Assoc., Inc. v. Certain Underwriters at Lloyds, London, 2010 U.S. App. LEXIS 14531 (5th Cir. July 14, 2010).

   Penthouse's property was completely destroyed by Hurricane Katrina, leaving only a slab.  Penthouse recovered the policy limits from its flood insurer.  It then sought coverage from Lloyd's under its all-risk policy. 

   Lloyd's policy excluded water damage, including flood.  The policy's anti-concurrent causation clause provided that "such [water] loss or damage is excluded regardless of any other cause of loss or event that contributes concurrently or in any sequence to the loss."  The policy also had a Windstorm or Hail Deductible endorsement.  This endorsement stated,

   The [endorsement] . . .  applies to loss or damage to Covered Property caused directly or indirectly by windstorm or hail, regardless of any other cause or event that contributes concurrently or in any sequence to the loss or damage.  If loss or damage from a covered weather condition other than windstorm or hal occurs, and that loss or damage would not have occurred but for the windstorm or hail, such loss or damage shall be considered to be caused by windstorm or hail and therefore part of the windstorm or hail occurrence. 

  Lloyd's denied Penthouse's claim based on the flood exclusion and the anti-concurrent causation clause.  Penthouse sued, alleging that the winds destroyed the condos several hours before the storm surge.  Therefore, the loss was caused entirely by wind, not by flood.   The district court denied Lloyd's motion for summary judgment, determining that the Windstorm Deductible endorsement provided coverage for hurricane damage regardless of whether the damage was caused by wind or flood.  In other words, the deductible did not serve to limit coverage, but expanded coverage to include any damage caused "concurrently or in any sequence to" windstorm, even if the damage otherwise would not have been covered under the flood exclusion.

   The Fifth Circuit reversed.  The plain language of the endorsement only described when the deductible applied.  The purpose of the broad language was to ensure that an insured could not escape the applicability of the higher deductible for windstorm damage simply because other weather events (with lower deductibles) contributed to the loss.