Abū Ḥanīfah said: if the option is exercised within three days, the sale is valid; but once the three days pass, the contract becomes void.

Al-Shāfiʿī, however, held that it is void in every case.

These, then, are the views of the jurists of the major centers concerning the length of the option, and the questions they raise may be summed up as follows:
• Is an option permissible at all, whether left unrestricted or fixed to a term?
• If it is permissible with a fixed term, how long may that term be?
• If an unrestricted option is impermissible, is the condition merely that it not extend into the three-day period, or is it unlawful altogether—even if confined to three days?

Their evidences are as follows:
The principal proof advanced by those who forbid the option altogether is what we have already mentioned.

Those who permit the option only for three days argue that the default rule excludes any option; consequently nothing may be allowed except what is explicitly established in the ḥadīth of Munqidh ibn Ḥibbān (or Ḥibbān ibn Munqidh). They regard this as one of the exceptional concessions that break from general principles, like the allowance of ʿarāyā sales despite the prohibition of muzābanah.
They add that the three-day limit is expressly set in the ḥadīth concerning the muṣarrāh animal:
“Whoever purchases a muṣarrāh has the option for three days.”

As for the ḥadīth of Munqidh, the soundest connected chain is that reported by Muḥammad ibn Isḥāq from Nāfiʿ from Ibn ʿUmar: the Messenger of Allah—peace and blessings be upon him—said to Munqidh, who was often cheated in sales,
“When you sell, say, ‘No deception,’ and you have the option for three days.”

The Mālikīs base their position on the notion that khiyār is the right to inspect and choose the merchandise. That period, they say, must therefore be limited to the time reasonably required for such inspection, which naturally differs from one commodity to another. In their view, the textual evidence merely points to this principle: the wording is particular, yet intended as a general rule. The first group, by contrast, treat it as confined to the very case named in the text.

Stipulating immediate cash payment, according to Mālik and all of his companions, is impermissible, because to them it hovers uncertainly between a forward sale and an immediate sale—a position they consider weak.

As for liability during the option period, the scholars differ:
• Mālik, his disciples, al-Layth, and al-Awzāʿī hold that any loss is borne by the seller, while the buyer is merely a trustee, whether the option belongs to both parties or to one of them alone. Within the Mālikī school another report states: if the goods perish while in the seller’s hand, he is unquestionably liable; but if they perish in the buyer’s possession, the ruling follows that of pawned or loaned property—if the loss is of a type normally ascribed to negligence, the buyer is liable; otherwise the liability reverts to the seller.
• Abū Ḥanīfah says: when the option is stipulated for both parties, or for the seller alone, liability remains with the seller, for the merchandise is still his property. If the option is for the buyer alone, the goods have left the seller’s ownership, while the buyer’s title to the price is still suspended until the option expires. Another report from him obliges the buyer to pay the price, implying that ownership has in fact transferred to the buyer.
• Al-Shāfiʿī has two opinions; the better known is that liability rests with the buyer, no matter in whose favor the option was stipulated.