The ruling regarding stipulations on the lineage of the offspring in a forward contract for animals.
Chapter on Guaranteed Salaf (Advance Payment) for a Specified Term
Al-Mughni
Book of Sales
Primary text
The initial prohibition reported against Ibn Mas'ud concerning the forward contract for animals was due to stipulations regarding the offspring (nutaj) of a known stud male. The statement attributed to 'Umar regarding the prohibition of Salaf in animals is construed, by those who hold it invalid, as pertaining specifically when they stipulate the offspring of the stud male of the tribe of so-and-so.