Neither Article 339 TFEU nor Article 28 of Regulation No 1/2003 explicitly indicates what information, apart from business secrets, is covered by the obligation of professional secrecy. It cannot be inferred from Article 28(2) of Regulation No 1/2003 that such would be the case as regards all information acquired under that regulation other than information whose publication is mandatory under Article 30 thereof. Like Article 339 TFEU, Article 28(2) of Regulation No 1/2003 – which supplements and applies that provision of the Treaty to the field of competition rules applicable to undertakings – prevents only the disclosure of information of the kind covered by the obligation of professional secrecy (see judgment of 28 January 2015, Akzo Nobel and Others v Commission, T‑345/12, EU:T:2015:50, paragraph 61 and the case-law cited).