The determination of the liability of a subsidiary for the anticompetitive conduct of its parent company ignited, long time ago, a sharp debate between those advocating for the single economic unit doctrine and those supporting the corporate separability doctrine. This paper, after making a brief journey through the diverse implications arising from the transposition of the European Union Damages Directive in Spain, elaborates on the locus standi of an undertaking within the meaning of Article 101 TFEU from what the author refers to as the legacy of ‘Skanska’. It takes stock of the difficulties that Spanish domestic Courts found in ascertaining the extent of liability that stems from a Competition Law damage claim within a corporate group. From the foundations of the case-law on the issue, the paper brings to the forefront the latest judgment of the Court of Justice on occasion of the clarifying preliminary ruling on the landmark ‘Sumal’ case.