Core rules
Residuary heirs (العصبة)
Asabah heirs take whatever remains after fixed shares are paid. Three sub-types: by self, by another, with another.
Residuary heirs — asabah — take whatever's left of the estate after fixed-share heirs have been paid. They have no prescribed fraction; their share is whatever the remainder happens to be.
Three sub-types
Asabah bin-nafs (by self)
Male relatives in a defined priority order. Each one, if present, takes the entire residue and excludes those below him on the list:
- Son
- Son's son (then son's son's son…)
- Father
- Paternal grandfather (then his father…)
- Full brother
- Paternal half-brother
- Full brother's son (then his son…)
- Paternal half-brother's son (then his son…)
- Full paternal uncle
- Paternal half-uncle
- Full paternal uncle's son
- Paternal half-uncle's son
Asabah bil-ghayr (by another)
Female relatives who become residuary because a male counterpart at the same level is present. They inherit at a 2:1 ratio with the male — male gets two parts, female gets one. This converts daughters, son's daughters, full sisters, and paternal half-sisters from fixed-share heirs into residuaries.
Asabah ma'a-l-ghayr (with another)
Full sisters and paternal half-sisters become residuary through the presence of female descendants (daughters or son's daughters). Without a male counterpart, the sister still becomes residuary because the daughter takes her fixed share first.
Why the order matters
Only one residuary "tier" inherits — the closest one present. A son excludes a son's son; a father excludes the grandfather; a full brother excludes a paternal half-brother. The whole residue goes to whichever male relative is highest on the list.
The father exception
The father is unusual: when descendants exist, he gets a fixed 1/6 and any remaining residue (which is rarely much). Without descendants, he's purely residuary. The grandfather follows the same pattern when no father is present.