Article 34 4.

The rights of defence of the gatekeeper, undertaking or association of undertakings concerned shall be fully respected in any proceedings. The gatekeeper, undertaking or association of undertakings concerned shall be entitled to have access to the Commission's file under terms of disclosure, subject to the legitimate interest of undertakings in the protection of their business secrets. In the case of disagreement between the parties, the Commission may adopt decisions setting out those terms of disclosure. The right of access to the file of the Commission shall not extend to confidential information and internal documents of the Commission or the competent authorities of the Member States. In particular, the right of access shall not extend to correspondence between the Commission and the competent authorities of the Member States. Nothing in this paragraph shall prevent the Commission from disclosing and using information necessary to prove an infringement.