Metadata plays a fundamental role beyond classified data, as data needs to be transformed, integrated, and transmitted. Like data, metadata needs to be harvested, standardized and validated. Metadata management processes require resources. The challenge for organizations is to make the processes more efficient, while maintaining and even increasing confidence in their data. While RDF harvesting has already become an important step implemented at large scale (European Data Portal), there is now a need to introduce a RDF validation mechanism. However such a mechanism will depend upon the definition of RDF standards. When a standard is set, the provision of a validation service is necessary to determine if metadata complies, as for example with the HTML validation service.