Almost 10 years ago, ZUGFeRD 1.0, the first invoice data format based on the public standards UN/CEFACT CII and PDF/A-3, was published. The stated intention was to digitize invoice exchange and make the transition from paper to data for SMEs and single users as smooth as possible without losing efficiency. The idea of using PDF/A-3 … Read more
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 … Read more
Digital signatures and PDF are an increasingly popular combination for digitizing paper-based business processes. While the focus of most signature products and solutions is on the creation of the signature itself, the correct validation of signatures contained in PDF is somewhat pushed into the background. Signature validation is a greater challenge for software development than … Read more
A short overview about the process of signing a PDF document with single or serial signatures is given. The special features of PDF to support signature workflows like certificate signatures and allowing for dedicated modifications after signing is presented. This is the origing of some of the complexity of the task to validate a signed … Read more