For a manufactured product, the origin material is one component of the BOM, used to manufacture the product, with the indication of its origin site.
For a traded material,  the origin material is itself, but with the indication of the origin site.
In both cases, the origin material is managed with a Special Procurement Key (SPK).
When a component is procured from another plant, using a special procurement key, the requirement is immediately visible at the sourcing plant. Even when the STR/STP is not yet created, it will appear under the form of "Dependent Requirements " in the planning table (MD04) of the origin site, and contribute to the determination of the total needs of the origin site, and to the calculations of its local MRP.

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