203 / Non-Authoritative Information (since HTTP/1.1)

“The server successfully processed the request, but is returning information that may be from another source.“ — wikipedia

“The returned metainformation in the entity-header is not the definitive set as available from the origin server, but is gathered from a local or a third-party copy. The set presented MAY be a subset or superset of the original version. For example, including local annotation information about the resource might result in a superset of the metainformation known by the origin server. Use of this response code is not required and is only appropriate when the response would otherwise be 200 (OK).“ — ietf

203 / code reference(s)
Rails HTTP Status Symbol
:non_authoritative_information
← return