PAdES (PDF Advanced Electronic Signatures) is a standard for contractually binding documents which was published in July 2009 by ETSI (European Telecommunications Standard Institute)
The PADES standard requires the incorporation of some permanent changes to the PDF document in order to comply with EU legislation and the ETSI Technical Specification (TS) 102 778
It works by creating an electronic signature on a digital document by making use of unique information about the signer, which is added to the document with an unbreakable stamp. The stamp can help identify signatories as well as detect changes in the document after it has been signed.
Signature data is therefore incorporated directly into the signed PDF document, just as the pen is on paper and this is in accordance with the eIDAS regulation.
In this way, Addo Sign complies with all the requirements of the PAdes standards.