So if you are a European the safest thing to do is simply assume the worst and go away now. I can't give you any opt in opt out option because I haven't got the vaguest idea how that is supposed to work. I just wasted several hours trying to figure out what the simplest solution is to protect myself and as far as I can tell this is some kind of protection racket. I'm sure it started off as something that was well intentioned, but politicians and lawyers frequently come up with things that may seem reasonable to them, but are technical nightmares or impossibilities for the technologists that have to implement the policies. I have a great deal of experience trying to explain technical issues to attorneys and it is almost never enjoyable or productive. The only thing that is clear to me is that people are already trying to profit from the resultant confusion.
All I wanted to do was share some information that I accumulated over twenty-eight years of working with U.S. Trademark information. It could be of interest to people outside the U.S. but since I can't figure what kind of legal trouble I could get myself into inadvertently and since evidently Europe now has the right to fine people outside their jurisdiction for something I don't even understand I'm unwilling to put myself at risk.
So, again, even though this probably does not technically comply with the GDPR, (a horrible acronym, but the way), assume I am Satan incarnate and leave this possibly diabolical blog as quickly as possible. I promise that I personally am neither collecting nor selling your personal data, but I have no idea what Google or any other software running in the background is doing with your data. And given how software is developed these days using many different packages from many different sources I certainly would not want to be responsible of ensuring compliance.
So protect yourself by not interacting with this blog in any way, please.