The PDF, by its nature, is a read-only format. Yeah, you got the Watermark On Pdf that allows you to modify it, etc.; and the Reader allows for some markup, but it was initially designed to be a global standard for read-only documents and/or digital forms that you can fill out. As such, people donât create documents in PDF â t create them in some other app (MS Word, Apple Pages, etc.) and then export them to PDF to be readable on any device. So what you need to do is add the watermark to your document in your designer app, and then export it to PDF together with the watermark. If you donât have access to the source document, only the PDF â then chances are you are not the creator of that PDF, so you donât really have any right to add a watermark to it. The above holds true for Mac, Windows, Linux, etc.
It is not our responsibility to have the PDF and the PDF creator sign any such documents for you.