
The billions may be lines in a spreadsheet
Clearly, the total number of people affected is far lower than the "billions of records" claimed by the leaker. For example, there are than 20 entries for me, across four states. I'm guessing the number of rows in a spreadsheet of the leaked data are what the leaker cited as the number of records, not discrete individuals.
FYI, I am a dual UK/US citizen who has lived in the UK for the last five years. Almost every place I lived in the US during the 35 years prior to 2019 is in the NPD leak, and all my old US phone numbers. I have not yet found out what UK info NPD holds or if mine was leaked. I also lived in the other country involved, Canada, but that was closer to 50 years ago.
I suspect that GDPR is making UK researchers reluctant to create a website where we Brits can check if we’ve been leaked. But please let me know if such a site comes up.