Any good suggestion(s) how to solve the following issue?

As part of one of the requirement, the business wants to have the possibility to maintain a certain piece of the Supplier Master data.

In general all masterdata of the Suppliers is maintained via one responsibility (‘ex: AP xxxxxx). This responsibility gives full access to all data, and via this responsibility a limited number of users are allowed to create and maintain supplier data.

Within the CPO department they are using the responsibility ‘PO xxxxxx’ to maintain all supplier contracts.

As part of this responsibility there is also a read-only access to the supplier data.

The business request from this CPO department is to remain this read-only access to the supplier data, but that they are able to maintain the ‘Contact Directory’ section of the supplier data. So all supplier data has to remain read-only, except the ‘Contact Directory’ section.