Use Portfolio feature.
Thanks, I finally worked it out. However, it's not an ideal format for how I originally visualised the outcome. From what I have read on the Adobe site and the discussion threads it doesn't appear that you can combine several digitally signed documents together to make a single document pack.
I had hoped that there was some way to have, say, 3 documents digitally signed by different people then merge these together into a single document but still retaining their individual signature details. This final document could then be certified by myself as the final recipient.
This final document pack could then be added to the final customers portfolio with many other documents.
The only way i can see to do this at the moment is to "sign" the documents with an annotation (ie. a JPG or PDF stamp), or use the built in stamps in COMMENTS, combine these into a single document and then digitally sign / certify this completed pack.
Has any one encountered this situation before and managed to solve it?
I understand that, because a change has been made to the original document this nullifies the orignal digital signature. I could live with this as long as I could retain the signatories details on that document.
A Digital PKI-based signature in PDF is based on the byte range of the signature content in the PDF file. If you move these bytes, the signature becomes unuasable. When you combine, say, 3 PDFs into one, the byte positions of the signatures in the 2nd and 3rd PDFs change, which makes these signatures unusable. This is why Acrobat's "Inset Pages" feature does not allow you to insert pages from/to digitally signed PDFs. There are other Acrobat features that also do not work with signed PDFs.
If you are fine with non-digital signatures, like stamps, this is a completely different story. There is a distinction between digital and electronic signatures. The former are PKI-based whereas the latter in many cases are not. You need to be clear on which signature types you need and act accordingly.
The reason for trying to utilise digital signatures throughout was to retain full authentication of the individual documents. This would be indisputable proof of the origin of the docs.
I am carrying out my trial with electronic signatures on the documents to be merged then digitally signing the final, completely merged, document.