What are the foundational elements of an 'Inan Partnership' (Shirkatu al-'Inan)?

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The 'Inan Partnership is established upon agency (Wakala) and trust (Amanah). Each partner entrusts their capital to the other as a trust, and by giving permission for disposition, the other becomes their agent. A condition for its validity is that each partner permits the other to transact business. If permission is granted generally for all trades, the partner may engage in them. If the permission is specified by commodity type, specific business, or location, the partner may only transact within those defined limits, as the disposition is dependent upon the specific authorization, similar to a general agent.