This research delves into the implications of property separation agreements under Law No. 1 of 1974, focusing on the period before and after the issuance of Constitutional Court Decision No. 69/PUU-XIII/2015. The law, which initially governed the separation of assets in the context of marriage dissolution, provided a presumption of joint ownership of property acquired during the marriage. However, the Constitutional Court’s ruling in 2015 significantly altered the legal landscape by recognizing the validity of property separation agreements, allowing individuals to define the ownership and division of property independently within the context of marriage. This study aims to explore the legal, social, and economic impacts of this decision. Prior to the Constitutional Court's intervention, property separation agreements were not explicitly recognized as a formal option under the law, creating ambiguity in the distribution of assets in the event of divorce. With the Court's ruling, individuals gained the ability to establish clearer boundaries regarding property ownership, which had broad implications for both personal financial planning and the equitable distribution of assets. The research investigates how this shift has affected various stakeholders, including married couples, legal practitioners, and courts in Indonesia. It also examines the challenges and uncertainties faced by individuals who wish to implement property separation agreements before marriage or during marriage. Through a thorough analysis of legal texts and interviews with legal professionals, this study provides insights into the evolving interpretation and application of property separation in Indonesia. Furthermore, it assesses the broader implications of the ruling on societal views towards marriage, property ownership, and individual autonomy within the context of marital agreements.