Google it. There are news articles about it. Have fun.>>5227116
Wacom specifically sells your computer app usage history to advertisers "anonymously" however there is a google ad number associated with you, and depending on programs you use and things you already search on google, websites you visit, etc. someone could probably identify you from it if they really tried. They define everything vaguely so that they can gather as much information as possible. Oh, and there's no way to opt out - if you have their drivers installed, you agreed to it. It's stated plainly in their terms that they can and will be doing this to you, and not just when your tablet is in use - any time your computer is on.
I don't even know why they feel the need to spy and sell users data for extra cash, and nobody knows who they sell the data to either. But yeah if you have noticed you've been getting targeted ads on google or youtube even with privacy settings and data collection turned off everywhere else possible, it's from your wacom drivers (which, by the way, are hard to completely uninstall. I tried multiple times with mine and the folder with all its data for running the service keeps coming back somehow. Hmm.)