Some scholars held that it is preferable—wherever possible—to describe the grandfather’s share simply as “one-third,” without actually awarding it to him as a fixed allotment, because fixed shares (farḍ) carry greater legal weight and the heirs who hold them are given precedence over agnatic heirs. Allah knows best.

Third situation: one-third of the entire estate is more advantageous to him than muqāsama, so he takes it as a fixed share.

The criterion for this is that the number of siblings exceeds twice his own, and the permutations here are not limited the way they were in the previous two situations. They include, for example: grandfather with two brothers and a sister; grandfather with five sisters; grandfather with one brother and three sisters, and anything beyond that.

Second overall situation: together with the grandfather and the siblings there is another heir who holds a fixed share.

In such a case the grandfather faces seven possible sub-cases, summarized as follows: (1) muqāsama alone is determined; (2) one-third of the remainder alone is determined; (3) one-sixth of the whole estate alone is determined; (4) muqāsama and one-third of the remainder are equal; (5) muqāsama and one-sixth of the entire estate are equal; (6) one-third of the remainder and one-sixth of the whole estate are equal; (7) muqāsama, one-sixth of the entire estate, and one-third of the remainder are all equal. The details are as follows.

First sub-case: muqāsama is more beneficial to him than either one-third of the remainder or one-sixth of the estate. An illustration is: husband, grandfather, and brother. Here the fixed share—the husband’s portion—is one-half, and the siblings are fewer than twice the grandfather’s number.

The reason muqāsama is obligatory in this example is that the half of the estate remaining after the husband is shared between the grandfather and the brother, and there is no doubt that one-half of that remainder—namely, one-quarter of the whole estate—is greater than one-third