Case C-238/05: Judgment of the Court (Third Chamber) of 23 November 2006 (reference for a preliminary ruling from the Tribunal Supremo (Spain)) — Asnef-Equifax, Servicios de Información sobre Solvencia y Crédito, SL v Asociación de Usuarios de Servicios Bancarios (Ausbanc) (Competition — Article 81 EC — System for the exchange between financial institutions of information on customer solvency — Reference for a preliminary ruling — Admissibility — Effect on trade between Member States — Restriction of competition — Benefit for consumers)