In G 1/05 of 7 December 2006 date: 2006-12-07 (OJ 2007, 362) the Enlarged Board stated that the principle of equal treatment and the right of parties to a fair trial enshrined in Art. 6(1) of the European Convention for the Protection of Human Rights and Fundamental Freedoms (ECHR) oblige the boards of appeal to decide the individual cases pending before them according to uniformly applied criteria and not in an arbitrary manner. In interlocutory decision G 2/08 of 15 June 2009 date: 2009-06-15 the Enlarged Board also stressed that it and the other boards of appeal act as judicial bodies and apply general principles of procedural law.

In its decision R 19/12 of 25 April 2014 date: 2014-04-25, the Enlarged Board observed that Art. 6 ECHR had been recognised in G 1/05 date: 2006-12-07 and G 2/08 date: 2009-06-15 as the binding standard for proceedings before the boards of appeal because it relies on principles of law common to all the European Patent Organisation's member states and applying to all its departments (see also D 11/91 date: 1994-09-14, OJ 1995, 721). This justified applying both national case law and that of the European Court of Human Rights as a supplementary means of interpretation for the EPC.