The ECJ judgments delivered in Arkema and Elf Aquitaine further develop the rules on application of the shareholding-based presumption which allows the Commission to impute to the parent companies liability for antitrust infringements committed by their subsidiaries. The ECJ reaffirms the rebuttable nature of the presumption and emphasises the need to conduct a detailed assessment of the parties’ arguments presented for the rebuttal of the above presumption. It remains to be seen what evidence the parties will need to present in order to succeed in rebutting the presumption.