It is a good idea to digitally sign PDF documents that you or your company creates. Just like software, a signature is an emblem of authenticity and helps to reinforce who is the author or else the distributor of the PDF. It helps all relevant parties hunt down the creator, and the added accountability might be essential for some documents. At the very least, your company should mark its photo assets as its property.
There are several ways to sign a PDF document. The first is to create the signature using the original Adobe software. There are other software that can both create PDFs or else edit existing ones to create the signature. Use software or online service that is quick and has all the options needed. It is not necessary to pay for an Adobe package when simpler tools do the trick faster.