You are creating a New Registered Product and you observe that under the section Supplier, the field Supplier Provisioning ID is greyed out.
SAP Business ByDesign.
Reproducing the Issue
Go to the Service Entitlements work center.
Go to the New Registered Product common task.
Click on View All button.
Under the section Supplier, you can see the field Provisioning Supplier ID greyed out.
This is the expected system behavior.
The field Provisioning Supplier ID is used in all standard applicable processes where a Supplier is involved for example - Standard Inbound, Third-Party Operations, Returns to Supplier and similarly. This field is filled in case the product involved has serial number profile maintained as "Mandatory for all Logistics and Production processes".
This field is used in certain validations to ensure that the Registered Products are returned to the same supplier.
The Provisioning Supplier ID is filled by the standard process determination and hence is written disabled (greyed out in the UI).
Registered Products ; Supplier ; Supplier Provisioning ID ; Greyed Out ; Serial Number. , KBA , AP-IBA-IPO , Installation Point , How To