8 Replies Latest reply on Jan 4, 2012 6:26 AM by vrotshteyn

    issue with multiple digital signatures disabling fast web view


      Hello, I'm using acrobat 9.1 pro and have some questions regarding an issue using multiple signatures on a pdf.


      Why am I asking the question below? My job involves preparing pdf's for submission to FDA. The FDA requires, among other things, that electronically submitted docs have fast web view enabled.


      I am currently exploring ways of using digital signatures to sign pdf reports and still make sure they are FDA spec compliant. My issue involves a document that would have multiple signature fields. What I do is create at least two signature fields in the doc and then save and optimize while enabling fast web view. When I sign the first box and save, the file retains the fast web view status. Yet, when I apply and signatures past the first one, the file is subsequently set to fast web view off without any obvious way of turning it back on. I am confused as to why it gets disabled only after the second, and not right after even the first one was signed. And, of course, I would like to know if it is possible to maintain fast web view and how to do it. I'll gladly accept "tinkering under the hood" of the file suggestions if they exist as well.


      Please let me know if anything is unclear or you need further information.


      Thanks for your time and help.



        • 1. Re: issue with multiple digital signatures disabling fast web view
          MichaelKazlow MVP & Adobe Community Professional

          I cannot tell you for sure, but I think the two things you want are incompatible. The signature is to guarentee among other things the file hasn't been changed. Wtihout downloading the entire file, the local copy of Reader or Acrobat cannot be determine if the file has or has not been changed.

          • 2. Re: issue with multiple digital signatures disabling fast web view
            CtDave Level 5

            My impression is that, if you use the FDA Electronic Submissions Gateway's forms you'd use Acrobat's Self-Sign to insert the digital certificate you'd acquired.
            (ref: http://www.accessdata.fda.gov/esg/userguide/webhelp/default.htm)


            As to a submitted PDF, the FDA PDF Specification does state -
            "Do not activate security settings... "

            As use of a digital certificate on a PDF you've made does involve imposing "security" I don't think you can do this with the PDFs you've created for submission. 


            Other than the just done 'quick look' I've no run time with FDA submissions.
            With that said, I'm something of an "old hand" with PDF submissions to another FedGov Agency.
            They too preclude 'security' on submitted PDFs.
            This is largely due to the requirement that FedGov agencies pass submitted records to NARA.
            So, NARA requirements dictate much of what an Agency electronic submittal requirements contain.



            Be well...

            • 3. Re: issue with multiple digital signatures disabling fast web view
              vrotshteyn Level 1

              right, but why does it work only if i have a single digital signature, or multiple digital signatures and only one is currently signed? To me it seems like it should either work all the time or none of the time. What else am I missing?

              • 4. Re: issue with multiple digital signatures disabling fast web view
                vrotshteyn Level 1



                This issue is not related to digitally signing and submitting the overall submission to FDA.


                I would like to use digital signatures to approve study reports and such, replacing the "wet" signature page with a page with digital signatures. It would be great to keep the integrity of the digital signatures in the file while still maintaining fast web view. Otherwise I have to re-distill and flatten the signature page, and use that intead, which kind of defeats the purpose of digital sigs and is on par with inserting a scanned wet signature page.


                In terms of security, the FDA does not want accept files that it needs a password to open or have setting applied to them like prohibiting printing. The digital signature only locks the document from modification, but all other security options are open. This can be seen on any of the forms that come directly from FDA with a digital signature block built in. The FDA will accept their own forms without a problem that are secured with a digital signature. Of course, those forms only have one digital signature field and do not become subject to the issue I'm having with multiple signature fields.


                Hope this provides more clarity and hope this can bring some additional answers or comments.

                • 5. Re: issue with multiple digital signatures disabling fast web view

                  I did find this forum with the title: "Enable Fast Web View in a PDF" http://help.adobe.com/en_US/Acrobat/8.0/Professional/help.html?content=WS58a04a822e3e50102 bd615109794195ff-7f52.html


                  Thought it might be worth the look.


                  I just checked a PDF I signed digitally with SIGNiX MyDox and it shows No for Fast Web View in the Properties tab.

                  Because it has already been signed, I do not think I can enable it to be viewed as a Fast Web View PDF, so says the forum.

                  I would take a look at the steps listed, and see if it helps your process.

                  • 6. Re: issue with multiple digital signatures disabling fast web view
                    vrotshteyn Level 1

                    Hi Andy,


                    So I already know how to set fast web view, this isn't the question, and I don't see anything on there that is relevant to anything that I've already mentioned in my previous posts.


                    I simply want to know if it is possible to preserve fast web view on documents with multiple digital signature blocks. It preserves fast web view with only one signature block but not when multiple are present and signed.


                    I would like to understand why the setting is preserved under one signature and lost under multiple and if there is ANY way to keep it set when dealing with multiple sigs.


                    Hope this is more clearer.

                    • 7. Re: issue with multiple digital signatures disabling fast web view
                      Steven.Madwin Adobe Employee

                      Hi Vlad,


                      Michael actual had the correct answer. The purpose of a "Linearized" file (i.e. a file that has been Optimized for Fast Web View) is to get the first page to display as soon as possible so you can start reading without waiting for the rest of the file to download. As an aside, the designated first page doesn't necessarily have to be page 0 (PDF's use a zero based counting system for pages), but usually it is. To quote the PDF specification, "The primary focus of Linearized PDF is optimized viewing of read-only PDF documents. It is intended that the Linearized PDF be generated once and read many times. Incremental update is still permitted, but the resulting PDF is no longer linearized and subsequently is treated as ordinary PDF."


                      When you sign a PDF file the first time the Save process is a "full save", that is the entire document is rewritten so there are no more than two %%EOF (end-of-file) markers in it. The first EOF designates which page to show first and the second EOF designates the end of the rest of the file (so the browser knows when to stop downloading). However, when you add a second (or subsequent) signature the file is saved as an "incremental save" and all of the new data is tacked onto the the end of the original file. This is so you can do a rollback to the previous signed version and allows Acrobat/Reader to check the integrity of each signature independent of any other signatures. It's the incremental save that breaks the linearized optimization of the file.



                      • 8. Re: issue with multiple digital signatures disabling fast web view
                        vrotshteyn Level 1

                        Thanks Steve,


                        Yes, now that I read Michael's answer, I see that it is in fact the correct answer, in very short form. But I appreciate your answer as to the technical details of why it does what it does, that's what I was looking for.


                        Thank you so much for this information and understanding what I was looking for!