The last filter before the numbers get distributed. This chapter condenses the hajb rules as formulated in the faraidh books (including at-Tahqiqat) into six rules plus one map.
Two kinds
- Hajb nuqshan — the share drops because of another heir’s presence: husband 1/2→1/4, wife 1/4→1/8, mother 1/3→1/6, granddaughter 1/2→1/6, paternal half-sister 1/2→1/6.
- Hajb hirman — total exclusion because someone closer is present.
The six immune to hajb hirman: father, mother, son, daughter, husband, wife — all connected to the deceased with no intermediary.
Hajb hirman map
flowchart TB
classDef aman fill:#134e4a,stroke:#14b8a6,color:#ccfbf1
classDef orang fill:#1e3a8a,stroke:#3b82f6,color:#dbeafe
classDef khilaf fill:#713f12,stroke:#ca8a04,color:#fef9c3
AY["Father"]:::aman -->|excludes| K["Grandfather"]:::orang
IB["Mother"]:::aman -->|excludes| N["Grandmother"]:::orang
AN["Son"]:::aman -->|excludes| CU["Grandchild"]:::orang
AY -->|excludes| SK["Full sibling(s)"]:::orang
AN -->|excludes| SK
K -.->|"tarjih: excludes ·<br/>madhhab: MUQASAMAH (chapter 08)"| SK
SK -->|excludes| SA["Paternal half-sibling(s)"]:::orang
KET["Descendants (m/f) & father/grandfather"]:::aman -->|excludes| SI["Maternal half-sibling(s)"]:::orang
SA -->|excludes| AS["Sibling's children"]:::orang
AS -->|excludes| PM["Paternal uncle → uncle's children"]:::orang
Note the dotted line grandfather→siblings: the one edge on this map where opinions diverge — under the madhhab (the position at-Tahqiqat teaches in full), the grandfather does not exclude full/paternal-half siblings but shares with them (chapter 08); under al-Fawzan’s own tarjih (and Ibn Uthaymin’s, Ibn Baz’s), the grandfather does exclude them.
Six summarizing rules
- Every heir is excluded by their own intermediary to the deceased — except maternal half-siblings (they inherit through sharing a mother, not through her, so the mother does not exclude them).
- Maternal half-siblings are the most fragile: excluded by any inheriting descendant and by male ascendants (father, grandfather). They only inherit in a pure kalalah case.
- Full siblings are excluded by a son, a grandson, the father (and the grandfather — opinion-dependent, see the map).
- Paternal half-siblings are excluded by everything that excludes full siblings, plus a full brother, plus a full sister as ‘ashabah ma’al-ghair, plus two full sisters (when there is no male helper).
- Granddaughters are excluded by a son or by two daughters — unless helped by a grandson (chapter 04).
- Mahjub still affects others; mamnu’ does not (chapter 02). Test case: mother + father + 2 brothers → the brothers are excluded by the father but still push the mother down to 1/6; father gets 5/6.
Check routine
For every name in a problem, ask three questions in order: is there a mani’? is there someone who totally excludes? is there someone who reduces the share? Whatever remains goes into the calculation engine in chapter 06.
Sources: at-Tahqiqat al-Mardhiyyah, chapter on al-hajb; al-Mulakhkhash al-Fiqhi (Shamela 11811); the grandfather dispute: IslamQA 240582. Full list in 15-references.