Judgment_paragraph 31 · Guardian Industries Corp. and Guardian Europe Sàrl v European Commission (C-580/12 P)

31The principle of equality of arms, which is a corollary of the very concept of a fair hearing and the aim of which is to ensure a balance between the parties to proceedings, guaranteeing that any document submitted to the court may be examined and challenged by any party to the proceedings, implies that each party must be afforded a reasonable opportunity to present his case, including his evidence, under conditions that do not place him at a substantial disadvantage vis-à-vis his opponent (Otis and Others, C‑199/11, EU:C:2012:684, paragraphs 71 and 72).