Is a forward contract (salam) valid for animal hides?
Chapter on Guaranteed Salaf (Advance Payment) for a Specified Term
Al-Mughni
Book of Sales
Primary text
The ruling regarding forward contracts (salam) for animal hides is the same as the ruling for heads and extremities. The validity of the forward contract is established because the variation within the hide is known and does not preclude its validity, similar to the validity of a forward contract for a live animal. A live animal encompasses various parts like the head, skin, limbs, flesh, fat, and internal organs, which inherently differ in quality and structure, yet a forward contract for the animal remains valid.
Supporting text
Imam Al-Shafi'i holds that a forward contract for hides is invalid because of their variability. He argues that specific parts of the hide differ significantly in thickness and texture—such as the thigh being thick and strong, the chest thick and soft, the belly thin and weak, and the back being the strongest—requiring a precise description of every location, which is impossible to measure due to the differing extremities.