In most of the world, anonymous data are not considered personal data — the information can be shared and sold without violating privacy laws. Market researchers are willing to pay brokers for a huge array of data, from dating preferences to political leanings, household purchases to streaming favorites.
But this anonymous information may not be anonymous after all.
Scientists devised a computer algorithm that can identify 99.98 percent of Americans from almost any available data set with as few as 15 attributes, such as gender, ZIP code or marital status.
This algorithm is now publicly available and can be used by vendors to secure future data sets and prevent individuals from being re-identified.