A class of contracts to which shari’a neither assigned specific names nor handled in details their respective rules and stipulations. Such contracts were formulated in response to new needs and requirements over time. Therefore, the number of these contracts cannot be counted for sure because there are plenty of them and new ones arise due to evolving needs of people and societies over time and across countries and geographical areas. Examples of these contracts include commissioned manufacturing (istisna’a), redemption sale (ba’i al-wafa), supply sale (ba’i al-istijrar), construction contracts, etc.

Aqd ghair musamma is an Arabic term (عقد غير مسمى) that translates as unnamed contract.