The Commission has instructed economical research agency LEAR to develop a detailed methodological approach for the ex-post review of the Commission’s merger control decisions, in particular to assess the impact of the Commission decisions on the market developments. LEAR were asked to apply this methodology to one particular case, the merger between cable producers Pirelli and BICC in 2000, which the Commission approved unconditionally after a Phase II investigation. The case involved both unilateral horizontal effects and possible collective dominance. On the key issues, the report confirms the Commission’s decision to allow the merger including the truthfulness of the factual assertions in the decision. The review identified two propositions by the Commission that were not sufficiently grounded on solid economic reasoning and two factors that were omitted from the Commission’s analysis. However, LEAR concludes that none of these had a significant impact on the overall competitive assessment and a proper assessment would not have changed the decision reached by the Commission. [1 February 2007]