Hans, with the following source, veraPDF-1.29.11 complains about a non-standard tag named /documentpart: \setuptagging[state=start] \setupbackend [format=PDF/A-3a, intent=sRGB IEC61966-2.1, level=0] \starttext whatever \pdfbackendactualtext{abc}{hoh} \stoptext The problematic object reads: 4 0 obj << /K 28 0 R /ParentTree 5 0 R /RoleMap << /break /NonStruct /document /Document /documentpart /DocumentFragment /navigationpage /NonStruct >> /Type /StructTreeRoot >> endobj If I replace (according to https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandards/PDF32000_2008....) /documentpart with /Part, validation in veraPDF is perfectly fine. BTW, /DocumentFragment seems not to be included in PDF-1.7 (https://opensource.adobe.com/dc-acrobat-sdk-docs/pdfstandards/PDF32000_2008....). According to https://github.com/veraPDF/veraPDF-model/blob/4c8e855b68546547971121281ff2ab..., /DocumentFragment seems to be only available in PDF-2.0. Providing a patch for strc-tag.lmt would be easy, but this would affect to ua-2 (which may use /DocumentFragment). Many thanks for your help, Pablo