I have a client which has a large amount of PDFs. I know that these do not have a tracking code on them, and have assumed we could not track pageviews and visitors landing on these pages. However, I then read this Moz article which suggests that you can by adding a campaign tag? Is this true?
I wouldn't use campaign tracking for this (campaign tracking is for use on external links for attribution, not internal links).
What you want is Event Tracking.
It's pretty straight-forward, especially if you use GTM.
I recommend avoiding doing this with inline code because it's error-prone and instead set up a script that will send an event when any (internal?) link ending in
You probably need to update the syntax shown in this article to the Universal (it uses the Async syntax) but this will give you a good idea about it.
You can add scripts to PDF: