The UK High Court decision on 8 February 2013 in AIOI Nissay Dowa Insurance Company Limited v Heraldglen Limited and Advent Capital (No 3) Ltd [2013] EWHC 154 removed any uncertainty in the reinsurance market by upholding an arbitration tribunal's decision that the terrorist attacks of 11 September 2001 on the Twin Towers of the World Trade Center (WTC) amounted to two "events" for the purposes of aggregation under a whole account catastrophe XL reinsurance wording.

The underlying losses principally arose from settlements for property damage/personal injuries claims made by the liability insurers of American Airlines (for flight AA11, which crashed into the North Tower), United (for flight UA175, which crashed into the South Tower) and the two security companies responsible for screening passengers on each flight. The issue was whether the losses arising from each act of hijack of the aircraft were one or two events under the reinsured's outwards XL reinsurances.

The case was reinsurer AIOI's appeal from an arbitration award dated 26 January 2012 made by a tribunal consisting of Ian Hunter QC, David Peachey and Richard Outhwaite. AIOI contended that its liability under the outward XL reinsurances was on a one-event basis, whereas Heraldglen had presented its claims to AIOI as two separate occurrences arising out of two separate events. The outward XL reinsurance contracts were subject to London Standard Wording 351, which provided that "each and every loss" is "each and every loss or accident or occurrence or series thereof arising from one event".

The tribunal had decided that the losses arising were caused by two separate occurrences arising out of separate events. The High Court upheld this finding on the basis that the tribunal had (i) correctly applied the law; (ii) had regard to all materially relevant matters; and (iii) did not take into account impermissible considerations.

In reaching this conclusion, the tribunal had evaluated the "four unities" test set out in the Dawson's Field arbitration and adopted by Rix J in Kuwait Airways Corporation v Kuwait Insurance Co:

  • The circumstances and purposes of the persons responsible
  • Cause
  • Timing
  • Location.

In relation to each of these:

  • The tribunal acknowledged that the hijackings were the result of a coordinated plot paid for by Al Qaeda, but observed that it was clear from the authorities that a conspiracy or plan cannot of itself constitute an occurrence or an event for the purposes of clauses in reinsurance contracts that refer to each and every loss, occurrence or event.
  • The tribunal was not satisfied that there was any basis, at least in the context of analysing unity of cause, for concluding that there was any factor amounting to an event of sufficient causative relevance to override the conclusion that two separate hijackings caused separate loss and damage. There were two separate causes because there were two successful hijackings of two separate aircraft.
  • The tribunal considered that there were clearly similarities in the timing of the events from the commencement of the flights to contact with the North and South Towers, but these were not such as to lead to the conclusion that there was either one occurrence or two occurrences arising out of one event. So far as timings were concerned, there were two occurrences and two events: infliction of personal injury and death started in the case of each aircraft shortly after they were hijacked and continued until at least the collapse of each of the North and South Towers, a period of 134 minutes in the case of Flight 11, and 72 to 76 minutes in the case of Flight 175.
  • The tribunal held that each tower was a separate building, albeit connected by a single mall. They did not stand or fall together. If only one of the hijackings had succeeded, only one tower would have been destroyed. The fact that both towers were destroyed was attributable to the fact that there were two successful hijackings directed at separate buildings forming part of the WTC.

The decision will be welcomed as it confirms the view taken by the majority of the market and removes any uncertainty as to the number of events.

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