The article aims to discuss the use of quantitative methods in quantifying merger effects as evidence, taking the particularities of the Brazilian experience and considering both technical, institutional and policy issues. Therefore, the article investigates evolution and patterns in the Brazilian institutional framework and jurisprudence in terms of technical aspects and adequacy of implementation, policy issues regarding the acceptance within the administrative tribunal and the main challenges imposed. The information collected considered all the merger cases, as far as we know, in which quantitative methods were applied by Administrative Council of Economic Defense (CADE) in order to measure, estimate or imply the merger’s potential anticompetitive effect on prices. Among the conclusions we find that the models are employed in few complex cases and mostly to sustain some restriction by the authority. We also note that the authority seems concerned about sensibility analysis, in some cases revealed by the combination of the use of different methods and/or competitive models.