In the recent case of Aioi Nissay Dowa Insurance Company Ltd v Heraldglen Ltd & Advent Capital (No 3) Ltd  EWHC 154 (Comm), 8 February 2013, the English Commercial Court upheld an arbitration tribunal’s award that the 9/11 terrorist attacks on the Twin Towers of the World Trade Center were properly described as two separate occurrences arising out of two separate events, for the purposes of an aggregation clause under a retrocession excess of loss reinsurance programme governed by English law.
Applying the ‘unities’ doctrine to the facts of the case, the arbitration tribunal (made up of Mr Ian Hunter QC as Chairman, Mr David Peachey and Mr Richard Outhwaite) concluded that the losses arising on the 10 inward reinsurances were caused by two separate occurrences arising out of separate events. The Commercial Court agreed with the tribunal’s reasoning and its conclusions on the agreed primary facts, which had been taken from the Final Report of the National Commission on Terrorist Attacks upon the United States.
The ‘unities’ doctrine is an English law test that derives from Mr Michael Kerr QC’s award in the Dawson’s Field Arbitration in 1972. It has been applied and developed by Rix J in Kuwait Airways Corporation v Kuwait Insurance Co SAK  1 Lloyd’s Rep 664, and subsequently affirmed by the English Court of Appeal in Mann v Lexington Insurance Co  1 Lloyd’s Rep 1 and Scott v Copenhagen Reinsurance Co (UK) Ltd  Lloyd’s Rep IR 696. The ‘unities’ test of aggregation has been stated to depend on the position and viewpoint of an informed observer (placed in the position of the insured), and it involves consideration of the degree of unity in relation to cause, locality, time, and, if initiated by human action, the circumstances and purposes of the persons responsible. The ‘unities’ test must be assessed by finding and considering all the relevant facts carefully, and then conducting an exercise of judgment and analysis. The exercise should be performed on the basis of the true facts (even if they are only discovered subsequently), and not simply on the basis of the facts as they may have appeared at the time.
Although specifically dealing with reinsurance contracts subject to LSW (London Standard Wording) 351, this judgment of the Commercial Court, and the underlying arbitration award, provide some welcome certainty to the reinsurance market generally on the issue of aggregation under English and Bermuda law.
A copy of the judgment can be found here: http://www.bailii.org/ew/cases/EWHC/Comm/2013/154.html