I heard that the Prophet ﷺ was brought a case of inheritance shares involving a grandfather, and he gave him a third or a sixth.
سمعت النبي ﷺ أتي بفريضة فيها، جد، فأعطاه ثلثا أو سدسا.
Ibn Majah (2722) narrated it from Abu Bakr bin Abu Shayba, who said, Shababa told us, who said, Yunus bin Abu Ishaq told us, from Abu Ishaq, from Amr bin Maymun, from Maqil bin Yasar Muzani, who said... and he related it. Its isnad is hasan because of Yunus bin Abu Ishaq, for his hadith is hasan, except that there is disagreement over his narration. Shababa narrated it from him this way, and this version is found in Ibn Abu Shayba (11/291).It was also narrated from Abdul-Ala, from Yunus, from Hasan, that Umar said, "Who knows the ruling of the Messenger of Allah ﷺ concerning the grandfather's inheritance?" Maqil bin Yasar Muzani said, "The Messenger of Allah ﷺ ruled on that regarding us." Umar said, "What was it?" He said, "A sixth," without doubt. Umar said, "Together with whom?" He said, "I do not know." Umar said, "May you not know! What use is that then?"This route was also narrated by Ahmad (20310), and likewise Abu Dawud (2897) narrated it from Khalid, and also from Yunus. But Hasan did not hear from Umar bin Khattab.However, Ibn Majah (2723) and Bayhaqi (6/244) both narrated it, from Yunus bin Ubayd, from Hasan, from Maqil bin Yasar, that the Messenger of Allah ﷺ ruled that the grandfather receives a sixth. This is how it appears in Ibn Majah. In Bayhaqi's version, Umar asked the people, "Who knows anything from the Messenger of Allah ﷺ regarding the grandfather's inheritance?" Maqil said, "He gave him a sixth." Umar said, "Together with whom? Woe to you!" He said, "I do not know." Umar said, "May you not know."There is disagreement about whether Hasan actually heard from Maqil bin Yasar. Abu Hatim denied this. Abu Zura said, "Hasan from Maqil bin Yasar is more plausible, while Hasan from Maqil bin Sinan is very far-fetched." Ibn Main said, "They have mentioned that Hasan heard from Maqil bin Yasar, but this is not widely established."I say, in Sahih Bukhari (4529), Hasan said, "Maqil bin Yasar told me," and then he related it. In summary, the hadith of Maqil bin Yasar is sahih in its isnad when the two routes are combined.As for what was narrated from Imran bin Husayn, that a man came to the Prophet ﷺ and said, "My grandson has died, so what share of his inheritance do I have?" He said, "You get a sixth." When the man turned to leave, the Prophet called him back and said, "You get another sixth." When he turned to leave again, the Prophet called him back and said, "That other sixth is a grant." Qatada said, "So they do not know together with what he inherited it." Qatada also said, "The least share the grandfather ever inherited was a sixth." This hadith is daif.It was narrated by Abu Dawud (2891), Tirmidhi (2099), Ahmad (19848), Daraqutni (4/84), and Bayhaqi (2446), all of them through the hadith of Hammam bin Yahya, from Qatada, from Hasan, from Imran bin Husayn, who related it. Tirmidhi said, "Hasan sahih." I say, rather it is daif, because Hasan never heard anything from Imran bin Husayn, as stated by Ali bin Madini, Yahya bin Main, Ahmad bin Hanbal, Bahz bin Assad, and others.Likewise, what was narrated from Ibn Abbas, that the Messenger of Allah ﷺ gave a grandmother a sixth of the inheritance, is not sound. It was narrated by Ibn Majah (2725), from Abdul-Rahman bin Abdul-Wahhab, who said, Salm bin Qutayba told us, from Sharik, from Layth, from Tawus, from Ibn Abbas, who related it. In this chain is Sharik the judge, and his teacher Layth, both of whom have poor memory, though the latter's memory became severely confused, so that his narrations can no longer be distinguished reliably.Likewise, what was narrated from Abdullah bin Masud regarding a grandmother alongside her son, that she was the first grandmother to whom the Messenger of Allah ﷺ gave a sixth alongside her living son, is not sound. It was narrated by Tirmidhi (2102), from Hasan bin Arafah, Yazid bin Harun told us, from Muhammad bin Salim, from Shaybi, from Masruq, from Abdullah bin Masud, who related it. Muhammad bin Salim is Hamdani Kufi, who is daif by unanimous agreement of the scholars. This route was also narrated by Bazzar in his Musnad (5/325) and by Bayhaqi (6/226).Tirmidhi said, "We do not know this hadith as a marfu narration except through this route. Some of the companions of the Prophet ﷺ gave the grandmother a share alongside her son, while others did not give her a share." Bazzar said, "We do not know anyone who narrated this hadith except Muhammad bin Salim, and no one else corroborated him. This Muhammad bin Salim is weak in his hadith." Bayhaqi said, "Muhammad bin Salim narrates this alone in this form. It has also been narrated from Yunus, from Ibn Sirin, who said, 'I was informed,' and from Ashath bin Sawwar, from Ibn Sirin, from Abdullah. And from Ashath bin Abdul-Malik, from Hasan and Ibn Sirin, from the Prophet ﷺ. But the hadith of Yunus and Ashath is disconnected, and Muhammad bin Salim cannot be relied upon. Rather, the sound narration on this matter comes from Umar, Abdullah, and Imran bin Husayn." Then he traced through isnads from each of these three that they gave the grandmother a share alongside her son. End of quote.He also said in Marifa Sunan wal-Athar (9/115), "Muhammad bin Salim narrates this alone in this form, and he cannot be relied upon."The narration of Ashath was narrated by Darimi (2974), from Yazid bin Harun, from him, from Ibn Sirin, from Ibn Masud, who said, "The first grandmother given a share in Islam was a father's mother, while her son was still alive." Ashath is Ibn Sawwar Kindi, who is daif by unanimous agreement of the scholars. Also, Ibn Sirin never met Ibn Masud.The correct position regarding the hadith of Abdullah bin Masud is that it is mawquf, attributed to him alone. Bayhaqi narrated it through the hadith of Sufyan, from Ibn Abu Khalid, from Abu Amr, from Abdullah bin Masud, that he gave a grandmother a share alongside her son. Its isnad is sahih.It has also been narrated from him, "Grandmothers have no inheritance right, it is merely a grant we give them, so the nearer and the farther among them are treated the same." This was narrated by Darimi (2985), from Yazid bin Harun, Ashath informed us, from Ibn Sirin, from Ibn Masud, who related it. This route through Ashath, namely Ibn Sawwar, was also narrated by Bayhaqi (6/226). Ashath is daif, and furthermore there is a break in the chain.On this subject there is also what was narrated by Abu Yaala (1095) and Bazzar in Kashf Astar (1387), both through the hadith of Qabisa bin Uqba, who said, Sufyan Thawri told us, from Zayd bin Aslam, from Iyad, from Abu Saeed Khudri, who said, "We used to give him a share in the time of the Messenger of Allah ﷺ," meaning the grandfather.Bazzar said, "We do not know this wording except through this route from Abu Saeed, and I think that Qabisa erred in his wording. In my view it should be 'We used to pay it,' meaning Zakat al-Fitr. No one else corroborated Qabisa on this."Muslim likewise criticized this in his Kitab Tamyiz (pp. 189-190). As for Haythami, he said in Majmaa (4/227), "It was narrated by Abu Yaala and Bazzar, and the men of Abu Yaala's narration are the men of the Sahih."On this subject there is also what was narrated from Ubada bin Samit, "Among the rulings of the Messenger of Allah ﷺ was that two grandmothers share the sixth of the inheritance equally between them," in a long hadith. Abdullah narrated it in the Musnad of his father (22778), who said, Abu Kamil Jahdari told us, Fudayl bin Sulayman told us, Musa bin Uqba told us, from Ishaq bin Yahya bin Walid bin Ubada bin Samit, from Ubada, who related the hadith.Regarding Ishaq bin Yahya bin Ubada bin Samit, Ibn Adi said, "Most of his hadiths are not well preserved, and he has a long hadith concerning the rulings of the Messenger of Allah ﷺ." In Tahzib Kamal it says, "He narrated from Ubada bin Samit but never met him. Musa bin Uqba narrated from him, and no one else narrated from him." His summary in Taqrib is, "He narrates from Ubada via a disconnected chain, and his status is unknown."As for his hadith concerning the rulings of the Messenger of Allah, this is what Ahmad mentioned (22778) with the isnad noted above.Ibn Abbas held the view that a grandfather is treated as a father, and he would recite the words of Allah, "the religion of your forefathers, Ibrahim and Ishaq" [Yusuf 12:38]. It is narrated from Ibn Jurayj, who said, Ata informed me that Ibn Abbas used to treat the grandfather as a father.As for those among the companions who held that a grandmother does not inherit alongside her son, they were Uthman, Ali, Zayd bin Thabit, , all together.