According to http://www.digitalpreservation.gov/formats/fdd/fdd000251.shtml#sign there should be two elements in the XMP-metadata to indicate the PDF/A conformance level. Here is an example: <rdf:Description rdf:about="" xmlns:pdfaid="http://www.aiim.org/pdfa/ns/id/"> <pdfaid:part>1</pdfaid:part> <pdfaid:conformance>B</pdfaid:conformance> </rdf:Description> or attribute version: <rdf:Description rdf:about="" xmlns:pdfaid="http://www.aiim.org/pdfa/ns/id/" pdfaid:part="1" pdfaid:conformance="B" /> See also http://www.pdfa.org/wp-content/uploads/2011/08/tn0008_predefined_xmp_properties_in_pdfa-1_2008-03-20.pdf and http://www.aiim.org/documents/standards/PDF-A/ISO19005AppNotes.pdf