How Ad Tech Sees You

Jon Keegan and Joel Eastwood, the Markup:

If you spend any time online, you probably have some idea that the digital ad industry is constantly collecting data about you, including a lot of personal information, and sorting you into specialized categories so you’re more likely to buy the things they advertise to you. But in a rare look at just how deep—and weird—the rabbit hole of targeted advertising gets, The Markup has analyzed a database of 650,000 of these audience segments, newly unearthed on the website of Microsoft’s ad platform Xandr. The trove of data indicates that advertisers could also target people based on sensitive information like being “heavy purchasers” of pregnancy test kits, having an interest in brain tumors, being prone to depression, visiting places of worship, or feeling “easily deflated” or that they “get a raw deal out of life.”

The apparent granularity and volume of these segments will likely not surprise anyone who has worked in digital advertising, but it is quite something to see it all in one place. It is remarkable to know this was published in the open, though it has now been taken down; while Xandr is now owned by Microsoft, the date in the filename and in its metadata indicates it was produced while Xandr was an AT&T subsidiary.

The Markup authors note you can ask to view the advertising segments you are in and request editing or removal. That, like many suggested avenues of recourse for anti-privacy technologies, is predicated on your knowledge of the businesses involved. For example, if you wanted to know if your information was in any way associated with Planned Parenthood — a segment which could be used against you in the United States — you must contact at least five different providers with segment names which contain “Planned Parenthood”, according to this list. Have you ever heard of Alliant or Eyeota? They might be associating your personal information with any number of segments based on indicators you do not know about. There are probably more businesses you have never heard of doing the same thing and it is up to you, individually, to ask for your information from all of them based on little understanding of this market, and then hope they honour your request to be removed.

If that feels overwhelming, that is because it is. Is it supposed to be? I would hate to be so cynical, but it is a solution for internet advertisers that heavily favours them, and only provides an illusion of control for individuals. This entire industry is built on deception and implied consent.