Abu al-Qasim al-Husayn ibn Ruh al-Nawbakhti

Abū al-Qāsim al-Ḥusayn ibn Rūḥ al-Nawbakhtī (Arabic: أبو القاسم الحسين بن روح النوبختي) was the third of the Four Deputies, who are believed by the Twelvers to have successively represented their Hidden Imam, Muhammad al-Mahdi, during his Minor Occultation (874–941 CE). Ibn Rūḥ in this role succeeded Abu Ja'far Muhammad ibn Uthman in 917 CE. After some twenty years in office, Ibn Rūḥ died in 937 CE and was succeeded by Abul Hasan Ali ibn Muhammad al-Samarri, the fourth and final deputy.