—there is no right of pre-emption for the co-owner in any of that. If the donor is later rewarded, pre-emption is still inoperative, because the original gift was made without consideration.

If a man marries a woman in exchange for a share of a house or other real estate, pre-emption applies to that share at its market value, not at the customary bridal dower. Should a settlement for deliberate homicide be concluded by transferring a share of a house, the partner may take that share by pre-emption at its assessed value; and if the settlement concerns accidental homicide, the pre-emption price is the fixed blood money (diyah).

The right of pre-emption does not arise until the purchaser’s transaction is fully concluded. It is no bar to pre-emption that, before the sale, the co-owner authorized the buyer to purchase and even waived pre-emption, whether or not the buyer recorded witnesses to that effect; likewise, the co-owner’s testimony to the sale itself does not forfeit his right.

Yet if, after the sale is complete, the would-be pre-emptor and the buyer haggle over the price of that share, his right lapses; the same holds if he bargains with him about leasing the share. This, too, is related from Malik. In the same vein, a waiver of pre-emption issued after the sale is final and every option of cancellation has expired is effective.

Suppose a man sells one half of his house under a sale that includes an option to rescind, and thereafter sells the other half by an outright, unconditional sale. The buyer under the unconditional sale may claim pre-emption, provided the option in the first sale lies with the purchaser and he elects to uphold the transaction; but if the option belongs to the seller and he chooses to annul it, no right of pre-emption arises.

Once pre-emption becomes obligatory through the purchaser’s completed contract, it cannot be extinguished by the buyer’s placing the property in waqf, giving it in charity, donating it, granting someone habitation rights, bequeathing it, or mutually cancelling the sale. The pre-emptor may acquire it despite all that by paying the sale price; every disposition the buyer has made concerning it is thereby nullified—although the buyer himself remains liable for what he has done, for he acted as the rightful owner at the time.

If the pre-emptor declines to exercise his right of pre-emption, and the buyer then sells the property