SAP EWM -WPT and Availability groups as per Warehouse design

Availability Groups are simply to represent storage locations.

In SAP ERP stock always belongs to a combination of plant and storage location. That means that the warehouse needs to keep the information in any stock which plant and storage locations it belongs to. But SCM (where EWM is based on) does not storage locations. The stock in SCM is handled by the LIME (Logistics Inventory Managment Engine) which knows stock types.

The combination of storage location and plant is assigned to an availability group. The "location independent stock type" which comes from ERP plus the availability group results in a LIME stock type.

What is the availabilty group field in the storage type for? This is for supporting a "storage locations scenario". This scenario is about having two storage locations. One (called ROD - received on dock) which is used for goods receipt and during moving the products into the warehouse. The other (AFS - Available for Sale) is used for outbound deliveries. When the material arrives in the final bin, the system triggers a posting change from one storage location to the other (assuming the proper availability group is entered and the flag "Mandatory" is set).

On the other side in EWM you see two roles in stock: the owner and the party entitled to dispose. The owner is the legal "owner", means he bought and paid it (this is is not a legal definitio

Now if a company which runs it's own warehouse, orders material and receives and puts it away in the warehouse, this company is both, owner and PETD - except in the case of consignment stock! In such a case the supplier / vendor still is the owner, but the company which received the material is the PETD. Until they decide to take the material and do something with it, then they become the owner.

Another scenario can be the one Kumar described - a logistic service provider running a warehouse for one (or several) clients and the stock is available for customers of these clients.