Then the reports that are rejected fall into one of two causes: either an omission (1) in the chain or a flaw detected through critique.
The omission (2) may occur (3) at the very beginning of the isnad (4) on the side of the compiler (5), at its tail-end after the Successor (tābiʿī), or (6) somewhere in between.
• The first is called muʿallaq (suspended).
• The second is mursal (detached).
• As for the third, if two or more consecutive links are missing it is muʿḍal (knotted); otherwise it is munqaṭiʿ (broken).
This break may be obvious or subtle.
• The obvious break is recognized by establishing that the two narrators never met; hence the need for chronological data.
• The subtle break is the mudallas (concealed report), transmitted with wording that could allow for an actual meeting (7 8), such as “ʿan” and “qāla.”
The same ruling applies to the hidden mursal reported by a contemporary who, in reality, never met the person in question (9).