sameAs Property
sameAs is a schema.org property that links an entity such as a company, a person or a product unambiguously to an external reference page, for example a Wikipedia or Wikidata entry or official social media profiles. It produces no rich snippet of its own; it clarifies identity for search engines and the Knowledge Graph.
In practice
For companies, sameAs is usually set in the Organization schema and lists URLs for profiles on LinkedIn, Instagram, Facebook, YouTube, Crunchbase or Wikidata. Google notes that sameAs on its own guarantees no Knowledge Panel entry, but that it does help mark your entity off clearly from others of the same name – particularly relevant for local SEO profiles and pages about individuals. Consistency is what counts: every linked profile should genuinely belong to the same brand or person, since outdated, private or incorrect links weaken the signal and should be reviewed regularly.