To print this article, all you need is to be registered or login on Mondaq.com. Before the EPO parameters are defined as features which are based on directly measurable properties or combinations of several variables in the form of formulae. This might be a claim defined by the viscosity of a composition, or the particle size of a powder, for example. Relying on such features to define an invention is commonplace within the chemical sphere and can be very useful. However, their utility is not limited to such subject matter and they could be used to define characteristic features in a broad