Heartland Payment Systems has agreed to a $3.6 million settlement with American Express relating to the criminal breach of the New jersey-based payments processor in 2008.
In a statement, Heartland says the payout resolves "all intrusion-related issues between the two parties".
Bob Carr, Heartland's chairman and chief executive officer, says: "This settlement marks the first agreement with a card brand related to the intrusion."
The firm is currently seeking to negotiate similar settlements with other schemes.
The deal with Amex comes just a month after Heartland revised its third quarter results by doubling the provision - to $73.3 million - for expenses related to the massive data breach it suffered last year, when intruders crashed the company's systems and potentially compromised the card data of millions of people.