The chains of Shī‘ī ijazahs of the period following Shaykh Tusī terminate mainly and mostly in him. Ibn Shahr Ashub writes in the introduction of the Manaqib, ‘‘The isnads of the books of our companions terminate mostly in Shaykh Tusī”. As many of Shaykh Tusī’s pupils were Iranians, the names in these ijazahs represent the links between the Shaykh and later scholars. Ibn Shahr Ashub, while mentioning the point that most ijazahs originate in Shaykh Tusī, gives a list of the intermediaries between himself and Shaykh Tusī, most of whom are Iranians. It is to be noted that Ibn Shahr Ashub carried out part of his studies in Iran and partly in Syria. These persons are: Abu al-Fadl Da‘ī Husaynī Sarawī, Abu al-Rida Fadl Allah Rawandī Qashanī, ‘Abd al-Jalil ibn ‘Isa ibn ‘Abd al-Wahhab Razī, Abu al-Futuh Husayn ibn ‘Ali Razī, Muhammad and ‘Ali, sons of ‘Ali ibn ‘Abd al-Samad Nayshaburī, Abu Ali Fadl ibn Hasan Tabrisī, and ‘Ali ibn Shahr Ashub Sarawī (his father). All of them are linked to Shaykh Tusī through Abu ‘Ali Tusī, ‘Abd al-Jabbar ibn ‘Ali Razī, Sayyid Muntaha ibn Abu Zayd Kiyabakī, Muhammad ibn Hasan ibn Fattal Nayshaburī, Shahr Ashub (his grandfather), and ‘Abd al-Jabbar. Ibn Shahr Ashub has also isnad through Arab scholars, such as Abu Ja‘far Muhammad ibn ‘Ali ibn Muhsin HalAbu, from Abu Ja‘far ibn Kumayh, from his father, from Ibn Barraj, from Shaykh Mufīd.
Ja‘far ibn Muhammad ibn Hibat Allah ibn Nama Hillī narrates Shaykh Tusī’s book IstibSar from his father, from his grandfather, from Husayn Miqdadī, who narrates it from ‘Abd al-Jabbar ibn ‘Ali Razī. ‘Allamah Hillī’s chain of authorities for the works of Shaykh Saduq and Shaykh Mufīd terminates in Ja‘far ibn Muhammad Duryastī and from him leads up to Shaykh Mufīd. He has another isnad for narration of the works of Shaykh Mufīd and Sayyid Murtada consisting of Arab intermediaries. Similarly, one of his chains of teachers in respect of the works of Shaykh Tusī is through ‘Imad al-Dīn Muhammad Abu al-Qasim Tabarī Amulī, the author of Basharat al-Mustafa, who narrates from Abu ‘Ali, son of Shaykh Tusī. Another isnad of his is through Burhan al-Dīn Muhammad ibn Muhammad Hamdanī Qazwīnī (resident of Ray), from Fadl Allah Rawandī, from Dhu al-Fiqar ibn Ma‘bad Marwazī, from Shaykh Tusī. His isnad for the works of Sallar ibn ‘Abd al-‘Azīz is through Murtada ibn Da‘ī Razī.
‘Abd al-Jabbar’s name occurs in many ijazahs relating to the narration of the works of Shaykh Tusī. Similarly, the name of ‘Ali ibn ‘Abd al-Samad Nayshaburī, a pupil of Shaykh Tusī, can be seen in many of these isnad. QuTb al-Dīn Sa‘īd ibn Hibat Allah Rawandī, in the isnad of the traditions of his book Qisas al-Anbiya’, mentions his authorities, among whom a number are Iranian scholars who were pupils of Shaykh Tusī, Abu Ali and ‘Abd al-Jabbar Razī. The opening traditions of this book are narrated from ‘Ali ibn ‘Abd al-Samad Nayshaburī, who was his own teacher. Other traditions are narrated by him from Murtada ibn Da‘ī, from Ja‘far Duryastī, from his father, from Ibn Babawayh and also from Dhu al-Fiqar ibn Ahmad Husaynī Marwazī, from Shaykh Tusī, and Abu ‘Abd Allah Husayn Mu’addab Qummī from Ja‘far Duryastī.
In any case, the names of these Iranian scholars can be seen in the ijazahs pertaining to the seventh/thirteen century onwards. An important instance is the ijazah considered to be from Sayyid Muhammad ibn Husayn ibn Abu al-Rida ‘Alawī (pupil of Yahya ibn Sa‘īd, author of al-Jami‘ li al-Shara’i‘) who gave it to Shams al-Dīn Muhammad ibn Ahmad, teacher of al-Shahīd al-Awwal.
This ijazah mirrors very well the presence of Iranian scholars in the generation after Shaykh Mufid, Sharīf Murtada, Sayyid Radī and Shaykh Tusī. They acquired their Shī‘ī learning in Iraq and delivered it to the scholars of Hillah. Here we will cite examples of the isnad mentioned in this ijazah.
Muhammad ibn ‘Abd Allah ibn Zuhrah > Ibn Shahr Ashub Mazandaranī > Dhu al-Fiqar Marwazī > Muhammad ibn ‘Ali Hulwanī > Sayyid Murtada.
Sayyid Muntaha Kiyamakī Husaynī > his father > Sharīf Murtada.
Muhammad ibn Fattal Nayshaburī > his father > Sharīf Murtada.
Muhammad Husaynī Baghdadī > QuTb al-Dīn Rawandī > Ibn A‘raj Naqīb > Ibn Qudamah > Sharīf Murtada.
Muhammad Husaynī Baghdadī > QuTb al-Dīn Rawandī > Murtada ibn Da‘ī Razī > Abu Ja‘far Duryastī > Sayyid Radī.
Ibn Shahr Ashub Mazandaranī > Muhammad and ‘Ali, sons of ‘Ali ibn ‘Abd al-Samad Nayshaburī > their father > Abu al-Barakat Khuzī > Shaykh Saduq.
Shadhan ibn Jibra’īl Qummī > ‘Imad al-Dīn Muhammad Tabarī > Abu ‘Ali Tusī > Shaykh Tusī > Shaykh Mufīd.
Muhammad Husaynī Baghdadī > Ibn Idrīs Hillī > Sharaf Shah Husaynī > Abu al-Futuh Razī Khuza‘ī > ‘Abd al-Jabbar Razī > Shaykh Tusī.
Muhammad Husaynī Baghdadī > Shadhan ibn Jibra’īl Qummī > Ahmad Hamdawayh Qummī > Hasaka ibn Babawayh > Shaykh Tusī.
Sharaf Shah Husaynī > Husayn ibn Abu al-Fath Jurjanī > Abu ‘Ali Tusī > Shaykh Tusī.
The chains of teachers mentioned in other isnads which are mentioned in this ijazah are also of a similar kind.
 Ibn Shahr Ashub, Al-Manaqib, (Beirut: Dar al-Adwa’ 1991) vol. 1, p. 32; Asad Allah Dezfulī, Manaqib al-Anwar (lithographed edition), p. 5; Tabataba’ī, ‘Abd al-‘Azīz, “Shakhsiyyat wa Mashayikh Shaykh Tusī,” Mīrath-e Islamī-ye Iran, daftar 2 (Qum: Kitabkhaneh Ayatullah Mar‘ashī, 1374 H. Sh. ), pp. 373-374.
 Ibn Shahr Ashub, op. cit., vol. 1, pp. 32-33.
 Majlisī, Bihar, vol. 104, p. 33.
 Ibid., vol. 104, pp. 69,70.
 Ibid., p. 136.
 Ibid., p. 100.
 Ibid., p. 144.
 Ibid., p. 71.
 Ibid., pp. 47-48.
 Rawandī, Qisas al-Anbiya’, pp. 52-65.
 Ibid., p. 73.
 Ibid., p. 120.
 Majlisī, op. cit., vol. 104, pp. 152-169.