Confidentiality is the opposite of publicity. It can be defined as an ‘obligation to 1 protect information that is not generally known and to use or disclose it only to approved persons, for agreed purposes’.1 Thus, the purpose of confidentiality is to prevent disclosure to third parties, but not the use of the information between the same parties. This definition also implies that a complete confidentiality cannot be achieved as, in some cases, the confidential information will have to be disclosed. Confidentiality is also one of the most controversial issues in international 2 commercial arbitration. On the one hand, it is widely recognised that confidentiality is an important advantage of international commercial arbitration, contributing to its attractiveness.2 On the other hand, there is no uniform regulation in national legislations, arbitration rules, and other relevant sources as to the scope or even to the existence of a duty of confidentiality.3 Moreover, there is currently an ongoing doctrinal debate over the existence of an implied duty of confidentiality—in the absence of a legal or contractual basis for such a duty.