Is there an option to revoke a sale due to gross overpricing (ghabn)?
Chapter on the Option of the Two Parties in Sale
Al-Mughni
Book of Sales
Primary text
The option to revoke a sale due to gross overpricing (ghabn) is established in specific instances. These instances include meeting incoming traders (talaqqi al-rukban) and buying from or selling to them resulting in ghabn, and the act of deceptive bidding (najsh). For the naive buyer (al-mustarsil) who suffers a ghabn exceeding customary limits, the option exists between voiding or confirming the sale. This view is held by Malik. The evidence supporting the establishment of choice in cases of ignorance-induced ghabn is analogous to the ghabn found in meeting incoming traders, as it results from the buyer's ignorance regarding the merchandise.
Supporting text
The opinion held by Ibn Abi Musa states that the sale is binding upon the naive buyer and he has no option to revoke it. This is also the madhhab of Abu Hanifa and Al-Shafi'i, who argue that a reduction in the value of the commodity, despite its soundness, does not prevent the finality of the contract, similar to the sale made by a non-naive person or minor ghabn. Furthermore, for one who is aware of potential ghabn or who would have known had they delayed, if they rush the transaction and are overcharged, they have no option to revoke because the outcome is based on their own negligence and lapse.