In order to remove redundantly mapped identifiers for the LIPID MAPS, Reactome, and WikiPathways content, additional quality control measures were performed related to the mapped identifiers obtained from BridgeDb to Wikidata. For all metabolic content, the RDF was checked for the number of mappings that were created starting from the original identifier as annotated in the pathway to Wikidata. If more than one Wikidata identifier was mapped, these identifiers were inspected manually; incorrect mappings were removed, and overlapping identifiers were merged. Only Wikidata provides access to the research community for both curation actions. This additional quality control step was performed with the SPARQL query as depicted in Code Example 1, with Blazegraph (blazegraph.com) on the RDF content of 2020-11-16 of LIPID MAPS, Reactome, and WikiPathways for all pathways (regardless of curation status). The RDF content is created daily with the Jenkins automated software (available at jenkins.bigcat.unimaas.nl). The first part of the query provides all the required prefixes (which can be omitted when using the WikiPathways SPARQL endpoint, available at sparql.wikipathways.org); the second part shows the query to retrieve double mappings to Wikidata identifiers.