Case C-882/19: Judgment of the Court (Grand Chamber) of 6 October 2021 (request for a preliminary ruling from the Audiencia Provincial de Barcelona — Spain) — Sumal SL v Mercedes Benz Trucks España SL (Reference for a preliminary ruling — Competition — Compensation for harm caused by a practice prohibited under Article 101(1) TFEU — Determination of the undertakings liable to provide compensation — Action for compensation directed against the subsidiary of a parent company and brought following a decision finding only that the parent company participated in a cartel — Concept of an ‘undertaking’ — Concept of ‘economic unit’)