[leereeves]

To offer just one of many possible examples that come to mind: the FLoC cohort might cluster people who read articles about becoming parents, which, though not visible in the data Google has, correlates with future claims for fertility treatments, pregnancy, etc.

The insurance company has the data, and it doesn't even need to know any of the details, it just needs to realize that certain cluster numbers correlate with future claims.

Perhaps Google will think of some of these correlations, and flag articles about becoming parents as sensitive, but how many unexpected correlations might be overlooked?

[dialtone]

The only way to discover this is to buy traffic from that cohort to actually test the behavior. That being said the first version of floc uses just the domain name of your history.

I’m not sure how the insurance company gets that data though in your example.

[leereeves]

> I’m not sure how the insurance company gets that data though in your example.

AIUI, they can get customers' FLoC cohort when customers visit their site to pay bills (or do anything else), and see prospective customers' FLoC cohort when issuing quotes online.

Who knows what they'll be able to learn from that? I certainly don't, but I expect them to try, and that worries me.