There is an "easy-to-miss" system-maintained field on the Released Product named "Low-level code". This has been in most ERP solutions for decades as it dramatically speeds up MRP calculations (NOE: Net-Offset-Explode). It is the lowest level an item appears across Bills of Materials. By processing MRP math sorted by Low-level code you can guarantee only looking at any Released product once during an MRP run. In the early days, before Low-level code was invented, the sequence of Calculations was not so smart (e.g. by item number), The NOE's would happen many times before an item was completely planned.

The suggestion here is to maintain (also system-maintained) an Inter-company Low-level code. The key fields would be Company-Item Id/Variant Id-Coverage dimensions such as Warehouse. The low-level code would not just look at BOMs but would have to consider an established Sales-order, Purchase-order pair Interco relationship (new) as well as warehouse refill relationships (already modelled but I don't think considered in today's Low-level-code).

MRP would then be run ONCE, ACROSS ALL D365 companies, sorting by Intercompany Low-level code instead of BOM level low level code (consider it a "Supply chain low level code"). I understand that this would have to be implemented only in Optimized planning as legacy MPS is deprecated. This design has many advantages:

o Optimized planning would be significantly faster for multiple company planning.

o This second level of Circularity Check is important to catch.

o Defining the entire Supply Chain is better modelled (think BI and Azure Machine Learning)

Keep in mind that this is further defining the Supply-chain-model for Planning only. It doesn't stop exceptional reverse selling or transfers for an item that are in the opposite direction than planned, just like today.

o Sp