Kitab al-Makasib or Makasib (Arabic: كتاب المكاسب, lit. 'Transactions') is a two-volume Twelver Shi'ah legal manual of Islamic commercial law written on Fiqh by Morteza Ansari.[1][2] It remains a key textbook in the modern Hawza[3][4] and has been the subject of numerous commentaries.[5][6] Makasib and the notable work of Akhund Khorasani, Kefayah al-osul, are taught in advanced classes at the seminaries.[4][7] This book is one of the resources for the examination of the Assembly of Experts.[8]