(14)Directive 85/611/EEC sets out criteria to define UCITS which replicate bond or share indices. UCITS which comply with those criteria are subject to a more flexible treatment as regards issuer concentration limits. It is therefore necessary to develop a clear understanding of those criteria and to ensure their uniform application in all Member States. That entails giving further clarification as to whether a UCITS can be considered to be an index-replicating UCITS, and thus more certainty about the conditions which justify the preferential treatment of index-replicating UCITS.