An istisna’a contract in which the buyer (manufacture orderer, or almustasni’) doesn’t set a condition in the contract obliging the seller (al-sani’) to undertake manufacturing the subject matter (commodity, asset, item, etc) by himself. In this sense, the seller is legally or contractually allowed to fulfill his contractual obligations by entering into a second istisna’a contract with a third party seller, in which he becomes a buyer. The second contract is referred to as parallel istisna’a. The paralleling practice is similar to offsetting in conventional finance transactions.

Parallel istisna’a is also known as back-to-back istisna’a.