On 18 July 2017, Australia became the first state in the Asia-Pacific region to sign the United Nations Convention on Transparency in Treaty-based Investor-State Arbitration, also known as the Mauritius Convention. Globally, Australia was the 21st signatory to the Mauritius Convention, joining a number of other major signatories such as the UK, the US, France, Germany and Canada. The Convention will come into force on 18 October 2017, six months after its ratification by the first three states.

The Mauritius Convention extends the UNCITRAL Rules on Transparency in Treaty-based investor-State Arbitration, which took effect on 1 April 2014, to investment treaties that were concluded before that date. The Rules operate on an ‘opt-out’ basis, applying generally to investor-state arbitrations under investment treaties concluded after that date unless expressly excluded by such treaties. By expanding the coverage of the Rules, the Mauritius Convention is aimed at balancing the public’s interest in ensuring transparency in investor-state arbitration on the one hand, and the participants’ interest in maintaining a fair and efficient mechanism for resolving their disputes on the other. Substantively, the Rules require that key arbitration documents, such as the notice of arbitration, the response to the notice of arbitration, the statement of claim, the statement of defence, table of exhibits, written submissions, transcripts of hearings, and the final award, be made public, subject to an exception for confidential business information. The Rules also require hearings for the presentation of evidence and oral argument to be publicly accessible, again subject to a confidentiality exception.

As Australia has not yet deposited an instrument of ratification with the Secretary-General of the United Nations, the Mauritius Convention is not currently binding on Australia. However, after ratification occurs and after the Convention comes into force, the transparency requirements in the Rules will apply to investor-state arbitrations brought against Australia under its investment treaties with other Mauritius Convention signatories regardless of when such treaties were signed, except where the Rules are expressly excluded by any such treaties. This may lead some investors to consider bringing a claim under a pre-1 April 2014 investment treaty now, before the Rules become mandatory, to avoid getting caught by the new regime’s wide-ranging disclosure requirements.