sameAs KG Anchoring is layer 6 of the Entity Architecture and Governance Framework (EP-9). It requires linking the entity to verified Knowledge Graph URIs such as a DOI, ORCID, Wikidata or LinkedIn. It is high priority.
What layer 6 covers
Layer 6 covers the connection between an entity on a website and the same entity in trusted external records. EP-9 uses the schema.org sameAs property for this, pointing to verified identifiers such as a DOI, an ORCID record, a Wikidata item or an official profile.
Schema.org defines sameAs as the URL of a reference page that unambiguously indicates the item's identity. It is a statement of identity, not of relevance, so every URL in it must describe the same entity.
Choosing the right target
Choosing the right target depends on what the entity is. A published framework or paper is identified by its DOI. A person is identified by an ORCID record. An organization or a concept may have a Wikidata item. Pointing an entity at the record of a different entity breaks the identity claim instead of strengthening it.
This framework follows the rule on its own master page: the DefinedTermSet for EP-9 points to the DOI of the EP-9 deposit, and the author node points to the author's ORCID record.
External records must be real
External records must be real and consistent for the sameAs link to add anything. An empty profile, or one that describes the entity differently from the website, gives a machine two conflicting sources rather than one confirmed identity. Layer 9 is where that consistency is maintained.
Add sameAs links only after the record exists and matches. A link to a placeholder is a claim the target cannot support.
How is sameAs different from an ordinary link?
An ordinary link says two pages are related; sameAs says they describe the same entity. Pointing sameAs at a page about something else tells a machine the two are identical, which merges them instead of connecting them. Use sameAs only for records that describe exactly the same entity.
Checkpoints for layer 6
The checkpoint for layer 6 inspects the JSON-LD for a sameAs property and confirms that each URL resolves to a verified record of the same entity. They are taken from the 15-point EP-9 technical audit checklist and keep their original identifiers, so an audit report can cite each one directly.
| Checklist ID | Audit layer | Mandatory verification requirement | Tool and method |
|---|---|---|---|
| CHK-EP-09 | L6 KG Anchoring | sameAs property links to DOI (10.5281/zenodo.22934007) or ORCID. | JSON-LD Inspector |
Open every sameAs URL. A link that returns an error, or a record that describes something else, fails the layer even when the JSON-LD itself is valid.