Inheritance, throughout the history of nations, has been influenced by both sound and corrupt customs and traditions. In Islamic principles, the subject of inheritance holds a special place, with several verses of the sacred and guiding Quran, along with hundreds of jurisprudential rulings and principles, dedicated to it. Undoubtedly, inheritance is one of the most complex topics extensively discussed, analyzed, and argued in jurisprudential and legal texts under titles such as causes, barriers, and conditions of inheritance.



Inheritance rules pertain to the division of estates, established for general subjects, from which rulings for various specific cases can be derived—not through deduction and mediation but through application and adaptation, much like the application of a natural universal concept to its specific instances.



The aim of this study is to provide a comprehensive and detailed analysis of the jurisprudential rules of inheritance, with a focus on the views of Sheikh Tusi as presented in his book Al-Mabsut. By analyzing and examining these rules, the study seeks to derive relevant rulings and laws pertaining to inheritance, facilitating the resolution of issues related to it.



This research, in terms of its nature, is descriptive-analytical, describing the state of the subject, and is considered fundamental in terms of its research classification. The findings of this study revealed that, according to Imamiyyah jurisprudence and Iranian law (Article 862 of the Civil Code), the distribution of inheritance shares is based on the following classes:



a) Father, mother, children, and grandchildren. b) Grandparents (paternal or maternal, or both alive). c) Paternal uncles, aunts, maternal uncles, aunts, and their children.



If the first class is alive, the second class does not inherit, and similarly, if the second class is alive, the third class does not inherit.