(off-topic) concatenating signed PDF documents
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Dear list, I have a question for users with more knowledge on digitally-signed PDF documents. Is it possible to concatenate PDF documents (each signed by a different certificate [by a different person]) into a single PDF document without invalidating any signature? I tried to join all PDF files with pdftk, but digital signatures in the resulting file were invalid. I guess that I’m trying something impossible, but I’ll really appreciate the confirmation from somebody with experience in digital-signed PDF documents. Many thanks for your help, Pablo -- http://www.ousia.tk
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»If you have PDF documents digitally signed the only way to combine them preserving their signatures is to create a PDF Portfolio with Acrobat Pro.« Source: https://answers.acrobatusers.com/How-do-I-combine-multiple-files-to-one-PDF-... On 03/08/2017 06:37 PM, Pablo Rodriguez wrote:
Dear list,
I have a question for users with more knowledge on digitally-signed PDF documents.
Is it possible to concatenate PDF documents (each signed by a different certificate [by a different person]) into a single PDF document without invalidating any signature?
I tried to join all PDF files with pdftk, but digital signatures in the resulting file were invalid.
I guess that I’m trying something impossible, but I’ll really appreciate the confirmation from somebody with experience in digital-signed PDF documents.
Many thanks for your help,
Pablo
![](https://secure.gravatar.com/avatar/5955e8e90611e77ccbfc7721b6112027.jpg?s=120&d=mm&r=g)
On 03/08/2017 07:35 PM, Henri Menke wrote:
»If you have PDF documents digitally signed the only way to combine them preserving their signatures is to create a PDF Portfolio with Acrobat Pro.«
Many thanks for your reply, Henri. I saw that a way is attaching the PDF files to another PDF document. My understanding of PDF Portfoliios is that they are only a fancy way of presenting the attached files in the PDF. I’m afraid that adding attachments to a PDF file would make life too hard for the recipients of the file. Many thanks for your help, Pablo -- http://www.ousia.tk
participants (2)
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Henri Menke
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Pablo Rodriguez