On 15 June 2020, Japan notified the member states of the Association of South East Asian Nations (ASEAN) of its formal legal adoption of the First Protocol to amend the Japan-ASEAN Economic Partnership Agreement (JAEPA). Amongst other things, the First Protocol introduces an Investment Chapter into JAEPA, as Article 51 of Chapter 7 (JAEPA Investment Chapter). The JAEPA Investment Chapter is intended to promote and protect investments between investors from Japan and the ASEAN Member States (Brunei, Cambodia, Laos, Malaysia, Myanmar, the Philippines, Singapore, Thailand and Vietnam). It contains wide-ranging investment protections for investors from these jurisdictions and includes an investor-State dispute settlement (ISDS) mechanism. But the ISDS provisions have a twist – there are various novel features and innovations that show State practice in the area of ISDS is continuing to evolve and that Asian nations, increasingly experienced with ISDS, are at the forefront of these developments.