Case T-364/10: Judgment of the General Court of 16 September 2013 — Duravit and Others v Commission (Competition — Agreements, decisions and concerted practices — Bathroom fittings and fixtures markets of Belgium, Germany, France, Italy the Netherlands and Austria — Decision finding an infringement of Article 101 TFEU and Article 53 of the EEA Agreement — Coordination of price increases and exchange of sensitive business information — Single and continuous infringement — Burden of proof — Fines — Equal treatment — Proportionality — Principle that penalties must have a proper legal basis)