Disabling Third-Party Cookies Won’t Improve Online Privacy

Third-party cookies are widely considered marketing technology, but it’s publishers who ultimately place these cookies on their sites, John Hyland, VP of publisher solutions at Centro, told Built In.

Marketers incentivize usage, though, often paying a premium for ads on sites with third-party cookies enabled. The cross-domain tracking technology makes ad space more valuable, and less of a black box, to advertisers — they make it clear which behavioral profiles have seen a given ad, and how they reacted to it.

It varies by cookie, but, in theory, third-party cookies can track all kinds of data. That includes basic demographic information, like age and gender, as well as more complex traits, like political affiliation, browsing history and digital behaviors — like how far a user typically scrolls down a page.

“It’s so deep,” Hyland said, of Centro’s library of third-party data. Type any keyword, and it will summon reams of relevant data, allowing advertisers to target Buick owners, Quentin Tarantino fans — you name it.

Read more in Built in Chicago.