41Specifically, it has been held that in view of the fundamental role played by the notification obligation to render effective the Commission’s review of State aid, which is mandatory in nature, the undertakings in receipt of aid may not, in principle, entertain a legitimate expectation that the grant of the aid was lawful unless it was granted in compliance with the procedure provided for in Article 108 TFEU, and a diligent trader must normally be in a position to satisfy itself that that procedure has been followed. In particular, where aid is implemented without prior notification to the Commission, with the result that it is unlawful under Article 108(3) TFEU, the recipient of the aid cannot have at that time a legitimate expectation that its grant is lawful, unless there are exceptional circumstances (see, to that effect, judgments of 24 November 1987, RSV v Commission, 223/85, EU:C:1987:502, paragraphs 16 and 17; of 20 September 1990, Commission v Germany, C‑5/89, EU:C:1990:320, paragraphs 14 and 16; of 13 June 2013, HGA and Others v Commission, C‑630/11 P to C‑633/11 P, EU:C:2013:387, paragraph 134; of 27 January 1998, Ladbroke Racing v Commission, T‑67/94, EU:T:1998:7, paragraph 182; of 16 October 2014, Alcoa Trasformazioni v Commission, T‑177/10, EU:T:2014:897, paragraph 61; and of 22 April 2016, Ireland and Aughinish Alumina v Commission, T‑50/06 RENV II and T‑69/06 RENV II, EU:T:2016:227, paragraph 214).