6.9.2.3.2 Response Headers

If the UPS instance was updated but with modifications made by the Origin-Server, the response message shall include the following HTTP/1.1 header:

If optional attributes were rejected, the response message shall include the following HTTP/1.1 Warning header field:

If the request was rejected with an HTTP/1.1 409 status code, the response message shall include one of following messages encoded in an HTTP/1.1 Warning header field describing the nature of the conflict: