Common use of External Factors Clause in Contracts

External Factors. Chapter 4 will focus on external factors. First, it will discuss whether regulatory changes have affected the Conventions’ envisaged aim of unifor- mity; and if this is the case, to what extent. The regulatory changes will be assessed in light of both revisions to the initial text, and the emergence of new consumer rights at regional and domestic levels, as exemplified by the adoption in the European Union in 2004 of Regulation No 261/2004 establishing common rules on compensation and assistance to passengers in the event of denied boarding and of cancellation or long delay of flights (hereinafter ‘EU Regulation 261/2004’).61 Second, it will review the response formulated by Courts to the possible elements found in Chapter 2. The outcome of this analysis is designed to apply the interpretation principles detailed in Articles 31 to 33 of the 1969 Vienna Convention on the Law of Treaties (hereinafter the ‘1969 Vienna Convention’)62 to the possible aim of uniformity of the Conventions.