Case T-208/06: Judgment of the General Court of 30 November 2011 — Quinn Barlo and Others v European Commission (Competition — Agreements, decisions and concerted practices — Market for methacrylates — Decision finding an infringement of Article 81 EC and Article 53 of the EEA Agreement — Concept of single infringement — Duration of the infringement — Fines — Gravity of the infringement — Mitigating circumstances)