What is the ruling if a buyer returns an item due to a defect, and the seller denies it was his property?
Chapter on Selling the Musarrah (Animal with milk retained in udder)
Al-Mughni
Book of Sales
Primary text
The statement of the seller, accompanied by an oath, is accepted. This position is held by Abu Thawr and the Ahl al-Ra'y (the Companions of Opinion). Al-Awza'i held a similar view in a case regarding currency exchange where the returning party claimed the exchanged dirham was not the original, ruling that the money changer should swear an oath to affirm he delivered the correct amount, thus absolving him. This is because the seller is denying ownership of the specific item and denying the right to contract dissolution, and the statement of the denier is accepted.
Supporting text
If the return is based on an option (khiyar) other than defect, and the seller denies the item is his, the ruling shifts. Ibn al-Mundhir reported from Ahmad that the statement of the buyer is accepted, a view shared by Al-Thawri, Ishaq, and the Ahl al-Ra'y, because in this scenario, both parties agree on the right to dissolve the contract, unlike cases of defect.