The NYSE is behind this like Robert had said, they do their own investigations. According to a TS posting by one of their staff: if you got flagged as a pro it is because the NYSE found that you have some kind of link with a LLC/Corp, or have accessed research from them that they deem as being for professionals. Man, they have really lowered the bar - be careful.
I'd believe this if I had actually done these things. I have been forthcoming in this thread about my financial connections. There is no connection to me past or present to any sort of professional financial services. The NYSE would, I would hope, find in any investigation that I am certainly not a professional. I don't even have my CTA or series exams.