Case C-189/19: Judgment of the Court (Sixth Chamber) of 14 May 2020 (request for a preliminary ruling from the Bundesverwaltungsgericht — Germany) — Spenner GmbH & Co. KG v Bundesrepublik Deutschland (Reference for a preliminary ruling — Environment — Scheme for greenhouse gas emission allowance trading within the European Union — Directive 2003/87/EC — Article 10a — Transitional system of free allocation of allowances — Decision 2011/278/EU — Article 9 — Determining the historical activity level — Significant change in the capacity of an installation that took place before the baseline period — Determining the relevant baseline period)