Arabic (بيع الخيار) for a contract of sale (bay’) that is embedded with an option (khiyar), granting either party the right to rescind the contract within a specified number of days (e.g. 3 days). The period of limitation for the underlying option in the optional sale agreement isn’t a matter of consensus among scholars of different schools of thought (mazhahib). Some scholars consider three days as sufficient, while in the opinion of others no established period of limitation is known to be stipulated by shari’a. However, the length of the option’s period depends, in principle, on the object of sale.

For example, real estate properties take more time to assess than commodities, vehicles, or animals. Thanks to the embedded khiyar, the optional sale transaction, contrary to normal sales, doesn’t come into immediate effect once the agreement is made. Rather, it becomes binding when the option’s period expires, with no party having exercised his right to revoke the contract.