There is, however, a further divergence in how Ibn al-Qāsim’s position is interpreted. One reading maintains that any invalid musāqāh reverts to a market-rate lease, except in four situations; in those it returns to an equivalent musāqāh. The four are:
- A musāqāh on an orchard whose dates have already ripened and become edible.
- When the cultivator stipulates that the owner must work alongside him.
- When a musāqāh is combined with a sale in a single transaction.
- When the agreement covers the same orchard for one year at a one-third share and the following year at a one-half share.
A second interpretation holds that his underlying rule is this: if the invalidity arises because a corrupt lease has been introduced, or because the fruit has in effect been sold before its benefit becomes apparent—namely, when either party requires an additional cash payment—the agreement is reduced to a market-rate lease. Thus, if one stipulates that he will give the other a sum of dinars or dirhams, the extra payment is a void lease when it comes from the owner, and an invalid pre-sale of fruit when it comes from the worker. If, on the other hand, the defect stems from excessive uncertainty—such as contracting over several orchards of differing quality—the contract is referred to an equivalent musāqāh. All of this rests on juristic preference (istihsān) and not on strict analogy.
A fourth opinion is also reported: the contract is adjusted to an equivalent musāqāh so long as the worker’s share does not exceed the portion originally stipulated when the condition favoured him, nor fall below it when the condition favoured the owner. This much suffices for our present purpose.