PDF Days Europe 2012 — Berlin: PDF/A-2 Finalisation and Accessibility Foundations
PDF Days Europe 2012, held in Berlin in March 2012, marked the year the PDF/A-2 standard (ISO 19005-2) was published. The event explored the new capabilities of PDF/A-2 including JPEG2000, transparency, and embedded files, while also previewing the forthcoming PDF/UA accessibility standard.
Official event page →Key takeaways
- PDF/A-2 (ISO 19005-2) had just been published — the event was one of the first practical forums for exploring its real-world implications.
- PDF/UA (ISO 14289-1) was in final ballot — organisations began planning accessibility compliance programmes.
- ZUGFeRD and the hybrid e-invoice concept (PDF/A-3 + embedded XML) were previewed for the first time at a major event.
- European national archives reported PDF/A-1 exception rates of 10–30% for scanned legacy documents — motivating PDF/A-2 adoption.
- Approximately 200 delegates attended, representing archives, financial services, and PDF software vendors.
PDF/A-2: what changed from PDF/A-1
PDF/UA preview: accessibility on the horizon
ZUGFeRD and the emerging e-invoice PDF/A-3 discussion
European national archives and PDF/A migration
Frequently asked questions
What are the main differences between PDF/A-1 and PDF/A-2?
PDF/A-2 (based on PDF 1.7) adds several capabilities prohibited in PDF/A-1 (based on PDF 1.4): transparency is allowed, JPEG2000 compression is permitted, optional content (layers) is allowed if all layers are visible by default, embedded PDF/A-conformant files are permitted as attachments, and digital signatures with LTV are supported. PDF/A-2 has two conformance levels: A (accessible) and B (basic), plus U (unicode guarantee). Most organisations migrating from PDF/A-1 target PDF/A-2b as the minimum.
Is PDF/A-2 backward compatible with PDF/A-1?
All PDF/A-1 conformant documents are valid PDF/A-2 documents — PDF/A-2 is a superset. However, a PDF/A-2 document that uses features not in PDF/A-1 (such as transparency) is not a valid PDF/A-1 document. When creating new archival documents, target PDF/A-2 or PDF/A-3 rather than PDF/A-1 to take advantage of the expanded feature set. Validators like veraPDF can check conformance against any PDF/A level.
What is ZUGFeRD and which PDF/A version does it require?
ZUGFeRD (Zentraler User Guide des Forums elektronische Rechnung Deutschland) is a German e-invoicing standard that combines a PDF/A-3 document (human-readable invoice) with an embedded XML file (machine-readable invoice data in Cross Industry Invoice format). Because PDF/A-3 permits attaching any file type (not just PDF/A-conformant files), it can carry the XML attachment. ZUGFeRD is widely used in Germany and is the basis for the pan-European Factur-X / EN 16931 e-invoicing standards.
When was PDF/UA (ISO 14289-1) first published?
PDF/UA-1 (ISO 14289-1:2012) was published by ISO in July 2012. It is the first international standard specifically for accessible PDF documents, defining requirements for tagged content, reading order, alternative text, language identification, and navigation. PDF/UA-2 (based on PDF 2.0) was published in 2024. The PDF Association's PDF/UA resources include the Matterhorn Protocol (technical validation rules) and implementation guides.
Try it in your browser
The PDF tools and standards discussed at this event are available free — no account needed.