According to Note 6 of the InstantiateVnfData data type: "If the overridingVnfdId attribute is present the vnfProfileId attribute shall also be present.". It means that either both attributes must be defined or none of them. Currently, the Open API Specification does not support the attribute dependency as reported in this issue: https://github.com/OAI/OpenAPI-Specification/issues/256. However, a possible solution is to use an "intermediate" data type called, for instance, _vnfdInfo_ that contains two mandatory attributes, i.e., overridingVnfdId and vnfProfileId. This _vnfdInfo_ "intermediate" data type would be then included as an optional attribute in the VnfInstanceData data model, resolving the problem of the attribute dependency. On the other hand, this solution would make the VnfInstanceData, not in compliance with the SOL005ed431 specification.