Hanīfah, Ahmad ibn Hanbal, and others. However, if its owner appears, he may decline to ratify that disposition. As for an exchange involving such property, its owner, once identified, may not reject it. Rather, Islamic law confers authority to undertake the exchange because of the need. For example, if a man dies somewhere where there is no executor, heir, or judge, his travelling companions acquire authority over his property. They safeguard it and sell whatever they consider it beneficial to sell. Such a sale takes effect, and they may take possession of what they have sold; this does not depend upon the heirs’ approval. This is not an unauthorized disposition. Rather, it is recognized as an exercise of authority conferred by Islamic law because of the need, just as they have the authority to wash him, provide his shroud from his estate, bury him, and attend to similar matters. For the believers are guardians of one another.

With this understood, consider the seller who sold what he had purchased with that additional amount and received the price from the buyer. If it is held that the sale is invalid and cannot remain pending approval, and that the buyer is not required to return what he received from the seller, while the seller must return the price he received, then, if the buyer cannot return what he received, the seller may take its equivalent. This may be worth more or less than the price, though usually it is equal to it.

The same applies to what he purchased with that additional amount: he must return it to its owner, and its owner must return the additional amount to its owner. Thus, if the recipient of the wrongfully acquired additional amount does not return it, the wronged party is entitled