hidden unique PDF identifier

[Stephan Gropp]

I would like to distribute one PDF file to several people which contains personal data. I have to make sure to be able to identify these files later and trace them back to the original addressee, just in case they got forwarded to other people and finally several copies exist without permission. In the end I should be able to figure out to whom a specific file was sent in the first place.

In order to do that I had the idea to add an invisible hidden unique identifier for each addressee somewhere in the PDF document. For all the addressees the PDF should look the same, because the individual ids are invisible. But in fact each file is different, because of this hidden field, which I should be able to read, if I receive one of these documents again.

Any ideas how to do that?

 

[Leslie V]

Hello @gropp.s@lahoe.de,

Thank you for reaching out to us through our Community Forums!

You can create hidden form fields for this by going to the Forms ribbon and click on Text Field. Click and drag on the page to create the field. 

Then, right click on the text field and click on Properties:

In the General tab, you can change it from Visible to Hidden, using the drop down menu in the Common Properties section.

Detailed instructions can be found here: http://install.nitropdf.com/pro11/en/nitro-pro-11-user-guide-en.pdf

Hope that helps!