57By contrast, where a regulatory act entails implementing measures, judicial review of compliance with the EU legal order is ensured irrespective of whether those measures were adopted by the European Union or the Member States. Natural or legal persons who are unable, because of the conditions of admissibility in the fourth paragraph of Article 263 TFEU, to challenge an EU regulatory act directly before the EU judicature are protected against the application to them of such an act by the ability to challenge the implementing measures which the act entails (judgments of 19 December 2013, Telefónica v Commission, C‑274/12 P, EU:C:2013:852, paragraph 28, and of 6 November 2018, Montessori, C‑622/16 P to C‑624/16 P, EU:C:2018:873, paragraph 59).