Case C-150/11: Judgment of the Court (Second Chamber) of 6 September 2012 — European Commission v Kingdom of Belgium (Failure of a Member State to fulfil obligations — Directive 1999/37/EC — Registration documents for vehicles — Vehicles previously registered in another Member State — Change of ownership — Requirement of a roadworthiness test — Requirement of production of a certificate of conformity — Roadworthiness test carried out in another Member State — Non-recognition — Lack of justification)