Discover UA02 quick reference: Discover's CNP fraud code — cardholder claims non-participation in a card-not-present transaction. Merchant has 20–45 days to respond.
Cardholder's claim
"I didn't authorize this transaction."
Discover UA02 is the CNP fraud equivalent of Visa 10.4 / MC 4837 / Amex F29. Discover Network Dispute Rules apply — response window is 20–45 days depending on the specific sub-case. Evidence expectations mirror Visa's baseline.
Response deadline
20–45 days to submit representment. From the chargeback date. Varies by dispute path.
Common triggers
- True fraud
- Friendly fraud
- Card-testing patterns
Required evidence
3DS / ProtectBuy authentication
Discover ProtectBuy 3DS challenge success record.
AVS + CID match
Full match at authorization.
IP + device fingerprint
Session identifiers.
Delivery to AVS address
Carrier tracking to AVS billing address.
Typical win rates
| Scenario | Win rate | Notes |
|---|---|---|
| ProtectBuy 3DS authenticated | 80–90% | Liability shift to issuer |
| No 3DS + AVS + delivery | 35–55% | Weaker without authentication |
Win rates reflect Aurai's own book across Stripe, PayPal, and Shopify Payments as of July 2026, plus public MRC Global Fraud Survey 2024 baselines. Your results will vary.
Related reason codes
10.4Visa
Other Fraud — Card-Absent Environment
Cardholder claims they didn't participate in the transaction and the merchant was not in a card-present environment. The single most common fraud code in ecommerce.
4837Mastercard
No Cardholder Authorization
Mastercard's equivalent of Visa 10.4 — cardholder claims they didn't authorize the transaction in a card-not-present environment.
F29Amex
Card Not Present — Fraud
American Express fraud code for card-not-present transactions where the cardholder claims non-participation.
Frequently asked questions
What does Discover UA02 mean?
Discover UA02 is the reason code for "Fraud — Card Not Present." Discover's CNP fraud code — cardholder claims non-participation in a card-not-present transaction.
What's the response deadline for Discover UA02?
Merchants have 20–45 days to submit representment. From the chargeback date. Varies by dispute path.
What evidence is required to fight Discover UA02?
3DS / ProtectBuy authentication, AVS + CID match, IP + device fingerprint, Delivery to AVS address. Full detail in the Required evidence section above.
Can Aurai handle Discover UA02 automatically?
Yes — Aurai detects the reason code, assembles the specific evidence stack for it, and submits before the deadline. 25% only on disputes we win.
Reason code details reflect the current Discover rules as of July 2026 and may change. Discover is a trademark of its respective owner. Aurai is independent and not endorsed by Discover. Always check the current official rules before acting on any specific tactic.