Application of the Rule Mā Yuzman wa Mā Lā Yuzman in Modern Contracts: A Jurisprudential-Legal Analysis of Its Application in Insurance, Electronic Contracts, and Digital Services

The jurisprudential-legal analysis of the financial effects of invalid contracts constitutes one of the most critical discussions within the domain of transactional jurisprudence and the legal system of contracts. This issue gains novel dimensions when addressed in the context of modern legal relationships such as insurance contracts, digital interactions, data-driven services, and immaterial agreements. Such contexts necessitate a fundamental reassessment of traditional jurisprudential rules, including the rule "Mā Yuzman bil-Sahīḥ Yuzman bil-Fāsid" (that which entails liability in a valid contract entails liability in an invalid one). Within the Imami jurisprudential system, this rule—grounded in hadith, rationalist reasoning, and the customary practice of the jurists (sīrat al-mutasharriʿa)—has served as a principal mechanism for affirming reciprocal liability in the event of contract invalidity and the occurrence of possession (qabḍ). It holds a central position in traditional analyses of specified contracts. However, in the face of contemporary developments and the emergence of contracts lacking tangible structure or those based on data and software, the question of the rule's extensibility and adaptability to new customary norms arises as a serious and underexplored problem. Additionally, legislative gaps in Iranian law—including the absence of explicit reference to the jurisprudential basis of liability in the Civil Code, inconsistencies across specific laws, and ambiguities in judicial practice regarding defective or partially executed reciprocal contracts—have further complicated the matter. Nonetheless, Imami jurisprudence, leveraging its ijtihād-based capacities, is theoretically capable of establishing a coherent financial liability regime for emerging forms of contracting, through principles such as mā yuzman. Using a descriptive-analytical method, the present article elucidates the theoretical foundations of the mā yuzman rule, analyzes its application in Imami jurisprudence, evaluates its capacity to engage with new contractual structures, and examines the challenges of aligning it with Iranian law. Furthermore, it assesses the potential for ijtihād-based and legislative expansion of the rule. The findings of this study reveal that, provided the core concepts—such as qabḍ (possession), ʿiwaḍ (consideration), and muʿāwaḍa (reciprocal exchange)—are redefined according to rational custom and contemporary interests, the rule may function as an effective and applicable principle in the domain of liability for digital and data-driven contracts.