Fingerprint
Non-personal data shared in an RTB broadcast may include data about income, age and gender, habits, social media influence, ethnicity, sexual orientation, religion or political affiliation
The actual data is way more than that list and effectively constitutes a fingerprint in its own right. Just in case that's not enough, they supply a full fingerprint anyway subtly disguised in the form of a URL or something similar.
(I'm using the word fingerprint to mean "uniquely identify an individual.")
Biting the hand that feeds IT
