Why people open duplicates
- Repeat bonuses: a welcome bonus and a no deposit bonus on every new account.
- Getting around limits: bet and withdrawal limits apply to a single account.
- Getting around self-exclusion: the most dangerous case, a direct risk to the licence and to the player.
- Affiliate fraud: fake registrations to collect CPA payouts.
Warning signs
The same device or browser, a shared IP and address, identical payment details, similar names and dates of birth, the same behaviour: registration, bonus, withdrawal. Taken alone, none of these proves anything. Together they give a confident signal.
How to protect against it
- A rule in the terms: one account and one bonus per person, household, address and device.
- KYC before bonus winnings are withdrawn.
- Checks at registration: device fingerprint and matches against self-excluded players.
- Decisions based on a clause in the terms that the player has seen, not on suspicion.
Common mistakes
- Catching duplicates only at withdrawal. The bonuses have already been paid out and the player is already angry. Checks at registration and first deposit cost less.
- Treating one signal as proof. Students in the same halls of residence or colleagues in one office can share an IP. Decisions are made on the combination of signals.
- No matching against self-excluded players. A new account from a self-excluded player is not bonus fraud: it is harm to a person and a risk to the licence.