The condition in which entity representations are consistent across all platforms where the entity appears — website, Wikidata, LinkedIn, Crunchbase, directories, social profiles. Cross-platform coherence is built through comprehensive sameAs linking, schema governance, and propagation protocols. Cross-platform coherence enables AI systems to confidently merge signals: if all representations agree on core attributes, confidence increases; if representations conflict, confidence degrades. Cross-platform coherence is measured through coherence audits: checking whether name, industry, location, founding date, key relationships are consistent across platforms. Incoherence is the most common unforced error.