What is the method of inheritance when the paternal grandfather inherits alongside full or paternal siblings?
Chapter on Inheritance of the Grandfather
Al-Mughni
Book of Inheritance Shares (Farā'id)
Primary text
There are differing methods among those who allow siblings to inherit with the grandfather. 'Ali ibn Abi Talib would assign fixed shares to the female siblings first, and the remainder was to be shared with the grandfather, unless this sharing resulted in less than one-sixth for the grandfather, in which case he was assigned one-sixth. If there was one full sibling sister and half-siblings brothers, the sister received half, and the grandfather divided the remainder equally with the brothers, unless the division gave the grandfather less than one-sixth, in which case he received one-sixth. If all siblings were residuary heirs, the grandfather shared with them until his share reached one-sixth. If paternal descendants ('walad al-ab') were present with the grandfather and full/half-descendants ('walad al-abawayn'), the paternal descendants were veiled and did not participate in the division.
Supporting text
Ibn Mas'ud followed 'Ali's method for sisters but shared with brothers up to one-third. Zayd ibn Thabit's opinion, favored by Ahmad, is that the grandfather is treated as a sibling for division (muqasamah) or receives one-third of the entire estate, whichever is greater. If the division results in equality between the two, either distribution is permissible. If the division results in a lower share than one-third, the grandfather takes one-third of the total estate. When fixed shares exist, the grandfather receives the maximum benefit among (1) division of the remainder, (2) one-third of the remainder, or (3) one-sixth of the entire estate. It is established that the grandfather never receives less than one-sixth of the entire estate, even in cases of 'awl (exaggerated claims), unless the issue results in the siblings being veiled entirely.