At the cassation level in the Supreme Court, the application of the procedural Legal for proving bankruptcy is generally applied through the interpretation method due to the unclear norms of simple proof. This was seen in the practice of Bankruptcy Legal in Indonesia and verified in the case of PT. Telkomsel, this study examines the case in the light of the Bankruptcy Law. The normative legal research or doctrinal research method was used to carry out this study. The research design adopted three types of approaches: the legal approach, the matter approach, and the conceptual approach. This methodology was in compliance with the recommendations of Joni Emirzon (2007) who emphasized on the need of legal research sources in order to solve legal problems in any research study. Findings revealed that the judges in the Commercial Court expanded the definition of debt falling under Bankruptcy Legal - Suspension of Debt Payment Obligations, which received many criticisms from various parties. The Supreme court reverted the verdict stating that the Commercial Court is not obliged to reject bankruptcy provisions in the Law. The study implications include using the Insolvency Test model in future bankruptcy laws to make it easier to see evidence of a Bankruptcy matter include simple evidence or ordinary evidence.