Gambling sites secretly shared user data with Meta Pixel without consent
The Observer found that approximately one-third of 150 UK-licensed gambling websites automatically transmitted user browsing data to Meta Pixel without consent. Users who visited these sites subsequently received targeted gambling advertisements on Facebook despite never agreeing to data sharing or visiting gambling sites before.
What happened
The Observer conducted an experiment visiting 150 UK-licensed gambling websites without clicking consent to data sharing. In approximately one-third of the tested sites, Meta Pixel was embedded and automatically triggered upon page load, sending reports to Meta about visited webpages linked to unique user IDs.
The data shared included information about button clicks and other browsing activity. One site reported to Meta when users clicked a button indicating interest in placing a bet on a specific match, and another reported when users viewed a promotion for free spins.
Reported impact
When The Observer logged back into Facebook days after visiting the gambling sites, the feed was filled with gambling ads from various brands. Users had never placed a bet, played on a gambling site, or consented to being targeted with such ads.
Index analysis
Once data was shared with Meta, it was ingested into Meta's targeted ads system to profile users based on inferred interests. Meta then sold ads to companies wanting to target potential gambling customers, including those who never opted in to data sharing.
Classification
Sources and evidence
Sources not yet published
This record was researched and written by the Index from original reporting. Its sources are still being verified by an editor, and they are listed here once that check is complete. Until then the record carries no reviewer.