Case T-400/09: Judgment of the General Court of 12 December 2012 — Ecka Granulate and non ferrum Metallpulver v European Commission (Competition — Cartels — Market in calcium carbide and magnesium for the steel and gas industries in the EEA, with the exception of Ireland, Spain, Portugal and the United Kingdom — Decision finding an infringement of Article 81 EC — Price fixing and market sharing — Fines — Principle of the legality of criminal offences and penalties — 2006 guidelines for the calculation of the amount of fines — Mitigating circumstances — Cooperation during the administrative procedure — Proportionality — Ability to pay)