Digital signatures have been an integral part of the PDF specification since version PDF 1.3. No other document format has such a deep integration of signatures. Well over 90 percent of all signed documents are PDF.
This presentation shows the development of the digital signature component in the PDF standard from PDF 1.3 to ISO 32000-2, and highlights enhancements and improvements over time. Furthermore, current approaches are described regarding how limitations of the current standard could be addressed, such as the support of parallel signatures, notarization, long-term conservation of signed PDFs and the mapping of complex signature workflows.