After Tza Yap Shum v. Peru, the case of Sanum v. Laos, brought by a Macanese investor, reattracted public attention to the critical issue of the applicability of the People’s Republic of China Bilateral Investment Treaties in China’s Special Administrative Regions. The Permanent Court of Arbitration held the PRC-Laos BIT extends to Macao according to the purpose and context of the BIT, but its reasoning is not tenable as its logic is flawed. In comparison, in the appeal, the conclusion reached by the Singapore High Court seems plausible, but there are still queries to the Court’s admission of further evidence. The author argues that the PRC BITs are not applicable to Macao and Hong Kong, on the basis of analyzing the treaty interpretation methodologies of this case. Notwithstanding the fact that the final award has not been rendered as of now, the Sanum v. Laos Case carries significant meaning to investment protection in China’s SARs.