Case T-79/06: Judgment of the General Court of 16 November 2011 — Sachsa Verpackung v Commission (Competition — Agreements, decisions and concerted practices — Plastic industrial bags sector — Decision finding an infringement of Article 81 EC — Price fixing — Allocation of sales quotas by geographic area — Allocation of customers — Exchange of individualised information — Proof of the infringement — Duration of the infringement — Fines — Gravity of the infringement — Proportionality — Attenuating circumstances — Follow-my-leader role)