...
Externally defined, PKB hosted
PKB allows customers to upload their own code sets for some types of data.
By uploading their own code sets customers can facilitate more meaningful use of their data, such as having PKB map these code values to code values in another coding system, or to apply the customer's choice of privacy label to data points.
...
There are several concepts for which PKB has defined a custom code set. For example, the PKB Privacy Labels will be represented as coded security labels in the FHIR metadata.
...