How to combine drawings with digital signatures

[thierry75063]

I have multiple sheet that are digitally signed and I need to combined them. When I try to combine them I have the following:

Does anyone knows how to do it?

Thank you,

[George_Johnson]

Combing signed documents would invalidate any digital signatures, so Acrobat doesn't allow it. You can add signed documents as file attachments though.

[Bernd Alheit]

You can combine them as portfolio.

[thierry75063]

How to create a portfolio with Acrobat XI?

[Bernd Alheit]

In the combine window specify this under options.