Earlier quoted context omitted.
This log [0], right? Did you miss in the article that it's the `google_push` identifier that's being used for syncing between adtech companies? If you search for it (AHNF13KKSmBxGD6oDK9GEw5O0kvgmFa3qM30zpNaKl72Og), you can see it being included in requests to lots of different adtech firms' domains. [0] https://brave.com/wp-content/uploads/files_2019-9-2/sample_p...
There is unfortunately no way to prevent that part. BidRequest Data [0] and Request Time is already enough to fingerprint the user. "Google prohibits multiple buyers from joining their match tables." part is not technical, it is contract based. [0] Sample Data from Bid Request ip: "F\303\006" user_agent: "Mozilla/5.0 (Linux; Android 7.1.1; Pixel XL Build/NOF26V) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/56.0.2924…
Well there's absolutely a way: single-source JS and no CORS.