If this Query Parameter is supported and present with a value that is a valid Transfer Syntax UID, the response payload shall be encoded in the specified Transfer Syntax.

If it is not present, the response payload shall be encoded in the default Transfer Syntax for DICOM Web Services, which is Explicit VR Little Endian Uncompressed.

If the Query Parameter is supported and present, and if any of the following are true:

then the origin server shall return a 400 (Bad Request) response and may include a payload containing an appropriate error message.

If the parameter value is a valid Transfer Syntax UID, but is not supported by the origin server, the response shall be 406 (Not Acceptable), and may include a payload containing a list of the Transfer Syntaxes supported by the origin server.