Folks. It’s really not that complicated. I sell data aggregation suites that utilize 1st (internal), 2nd(other companies’ internal), and 3rd party(data aggregations like Neilson) data to create highly specific user profiles. You would be shocked at what a marketer, at, say, American Airlines can build with a few simple key strokes. To be fair, the software utilized by US firms is de-identified and is used for segmentation and population building purposes- but it would be very easy for someone with software engineering capabilities to reidentify the data. If you have ever - Bought anything online Had a social media account Responded to a promotional email (like from Home Depot) Given your email address to a doctor or a government Had an account with Amazon Had a Netflix account Or basically ever given anything other than a credit card number and SS number to a US company, you have a profile - and I sell the capability to utilize those profiles. And there are plenty of buyers.