Q: Legit repeat visitors look like the same device to the antifraud system. Is that bad?

Q: Legit repeat visitors look like the same device to the antifraud system. Is that bad?

A: It can be, and it's often a setup mistake rather than fraud. Device fingerprinting (an ID built from browser, OS, fonts, screen, and other signals) is meant to spot one machine pretending to be many users. But it also fires when many real users LOOK identical.

Where honest traffic gets caught:

— You drive traffic from inside one app's in-app browser (a messenger, a social app). Every user shares the same user-agent and rendering engine, so fingerprints collapse together.
— Privacy browsers and incognito mode strip the signals, so hundreds of users share one bland, low-entropy fingerprint.
— A misconfigured CDN or proxy rewrites headers identically for everyone.

Fix: check whether your flagged sessions share one user-agent or one fingerprint hash. If they do, it's your channel collapsing diversity, not a fraud ring. Add a legitimate signal the network accepts (a hashed login ID) so real distinct users separate cleanly.

Short version: identical fingerprints often mean one channel, not one fraudster. Find what's collapsing the entropy.

Still stuck? Drop your case in the comments.