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Mastercard 4840: Fraudulent Processing of Transactions (legacy)
What it means: The cardholder says they did not authorize or take part in this card-not-present transaction.
Mastercard has consolidated many older codes into 4808, 4834, 4837, 4853, 4863, 4870 and 4871; this legacy code may still appear on older or region-specific disputes.
How to respond: Show that the legitimate cardholder made (or benefited from) the purchase: matching identity signals, delivery to their address, prior undisputed history, and usage.
Stripe usually labels this dispute as: fraudulent (check the reason shown on your dispute — Stripe maps network codes to its own categories).
Evidence checklist
- AVS (billing address) and CVC check results from the original authorization (visible on the payment in Stripe)
- IP address, device / browser details and timestamps of the order, and how they match the customer's past activity
- Prior undisputed orders from the same customer (same email, card, address, IP or device)
- Shipping documentation: carrier, tracking number, delivery date and delivery address matching the address on the order
- Proof of delivery (carrier delivery confirmation; signature if obtained)
- For digital goods / SaaS: access or download logs showing the customer logged in or used the service after purchase
- Customer communication (emails, chat, support tickets) — especially anything where the customer acknowledges the order or the product
- Receipt / invoice showing what was purchased, price, date and the customer's details
Tips
- Address the specific reason code — a generic letter that argues the wrong issue is a common reason responses fail.
- Submit before the evidence due date shown in your Stripe/Shopify dashboard; most processors allow one submission.
- Keep it factual and concise; label each exhibit.
- If the customer is right, accepting the dispute or refunding may cost less than fighting it.
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DisputeDesk provides general information and document preparation help. It is not legal advice, and we do not guarantee any dispute outcome — the card issuer decides. Reason-code names and rules change; always check the dispute details in your Stripe or Shopify dashboard and the card network's current rules.
DisputeDesk is operated by Avenbridge Technology Limited (Hong Kong). Privacy